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100-Gb/s undersea transmission with high spectral efficiency using pre-filtered QPSK modulation format

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chinese Optics Letters 2010年第9期8卷 831-836页

作者： j.-X. cai Y. cai c. R. Davidson D. G. Foursa A. Lucero O. Sinkin W. Patterson A. Pilipetskii G. Mohs neal S. Bergano Tyco Electronics Subsea communications LLc ("TE Subcom" formerly known as ~co Telecommunications (US) Inc.) 250 Industrial Way West Eatontown NJ 07724 USA

We provide a review of our recent 100-Gb/s, high spectral efficiency （SE） experiment targeting transoceanic and regional undersea transmission distances. We demonstrated that simple pre-filtering at the transmitter together with a maximum a posteriori probability （MAP） detection algorithm can significantly improve SE. We transmitted 96×100-Gb/s pre-filtered polarization division multiplexed return-to-zero quadrature phase shift keyed （PDM-RZ-QPSK） channels with 300% SE over 10608 km using 52-km spans of 150-μm 2 fiber and simple single-stage erbium-doped fiber amplifiers （EDFAs）. We also achieved 400% SE over 4368 km using similar techniques.

关键词： Bit error rate Erbium doped fiber amplifiers Modulation Optical signals Quadrature phase shift keying Signal processing

Systematic review and meta-analysis of outcomes of anatomic repair in congenitally corrected transposition of great arteries

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World journal of cardiology 2020年第8期12卷 427-436页

作者： Arka chatterjee neal j Miller Marc G cribbs Amrita Mukherjee Mark A Law Division of cardiovascular Diseases University of Alabama at BirminghamBirminghamAL 35294United States Department of Pediatric cardiology University of Alabama at BirminghamBirminghamAL 35294United States Department of Epidemiology University of Alabama at Birmingham School of Public healthBirminghamAL 35233United States

BAcKGROUND Treatment of congenitally corrected transposition of great arteries(cc-TGA)with anatomic repair strategy has been considered superior due to restoration of the morphologic left ventricle in the systemic ***,data on long term outcomes are limited to single center reports and include small sample *** To perform a systematic review and meta-analysis for observational studies reporting outcomes on anatomic repair for *** MEDLINE and Scopus databases were queried using predefined criteria for reports published till December 31,*** reporting anatomic repair of minimum 5 cc-TGA patients with at least a 2 year follow up were *** was performed using comprehensive meta-analysis v3.0 *** Eight hundred and ninety-five patients underwent anatomic repair with a pooled follow-up of 5457.2 patient-years(PY).Pooled estimate for operative mortality was 8.3%[95%confidence interval(cI):6.0%-11.4%].0.2%(cI:0.1%-0.4%)patients required mechanical circulatory support postoperatively and 1.7%(cI:1.1%-2.4%)developed post-operative atrioventricular block requiring a *** surviving initial surgery had a transplant free survival of 92.5%(cI:89.5%-95.4%)per 100 PY and a low rate of need for pacemaker(0.3/100 PY;cI:0.1-0.4).84.7%patients(cI:79.6%-89.9%)were found to be in New York Heart Association(NYHA)functional class I or II after 100 PY follow *** re-intervention rate was 5.3 per 100 PY(cI:3.8-6.8).cONcLUSION Operative mortality with anatomic repair strategy for cc-TGA is *** that,transplant free survival after anatomic repair for cc-TGA patients is highly *** of patients maintain NYHA I/II functional ***,monitoring for burden of re-interventions specific for operation type is very essential.

关键词： congenitally corrected transposition of great arteries Anatomic repair Double switch operation Atrial switch Rastelli Hemi-Mustard Rastelli Atrio-ventricular block

Algorithm of Helmet Wearing Detection Based on AT-YOLO Deep Mode

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computers, Materials & continua 2021年第10期69卷 159-174页

作者： Qingyang Zhou jiaohua Qin Xuyu Xiang Yun Tan neal NXiong college of computer Science and Information Technology Central South University of Forestry&TechnologyChangsha410004China Department of Mathematics and computer Science Northeastern State UniversityTahlequah74464OKUSA

The existing safety helmet detection methods are mainly based on one-stage object detection algorithms with high detection speed to reach the real-time detection requirements,but they can’t accurately detect small objects and objects with ***,we propose a helmet detection algorithm based on the attention mechanism(AT-YOLO).First of all,a channel attention module is added to the YOLOv3 backbone network,which can adaptively calibrate the channel features of the direction to improve the feature utilization,and a spatial attention module is added to the neck of the YOLOv3 network to capture the correlation between any positions in the feature map so that to increase the receptive field of the ***,we use DIoU(Distance Intersection over Union)bounding box regression loss function,it not only improving the measurement of bounding box regression loss but also increases the normalized distance loss between the prediction boxes and the target boxes,which makes the network more accurate in detecting small objects and faster in ***,we explore the training strategy of the network model,which improves network performance without increasing the inference *** show that the mAP of the proposed method reaches 96.5%,and the detection speed can reach 27 *** with other existing methods,it has better performance in detection accuracy and speed.

关键词： Safety helmet detection attention mechanism convolutional neural network training strategies

Magnetic anchor guidance for endoscopic submucosal dissection and other endoscopic procedures

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World journal of Gastroenterology 2017年第16期23卷 2883-2890页

作者： Mohamed Mortagy neal Mehta Mansour A Parsi Seiichiro Abe Tyler Stevens john j Vargo Yutaka Saito Amit Bhatt Department of Internal Medicine Homer Stryker MD School of MedicineWestern Michigan UniversityKalamazooMI 49008United States Department of Internal Medicine Medicine InstituteCleveland ClinicClevelandOH 44195United States Department of Gastroenterology and Hepatology Digestive Disease InstituteCleveland ClinicClevelandOH 44195United States Endoscopy Division National Cancer Center HospitalTokyo 104-0045Japan

Endoscopic submucosal dissection(ESD) is a wellestablished, minimally invasive treatment for superficial neoplasms of the gastrointestinal tract. The universal adoption of ESD has been limited by its slow learning curve, long procedure times, and high risk of complications. One technical challenge is the lack of a second hand that can provide traction, as in conventional surgery. Reliable tissue retraction that exposes the submucosal plane of dissection would allow for safer and more efficient dissection. Magnetic anchor guided endoscopic submucosal dissection(MAGESD) has potential benefits compared to other current traction methods. MAG-ESD offers dynamic tissue retraction independent of the endoscope mimicking a surgeon's "second hand". Two types of magnets can be used: electromagnets and permanent magnets. In this article we review the MAG-ESD technology, published work and studies of magnets in ESD. We also review the use of magnetic anchor guidance systems in natural orifice transluminal endoscopic surgery and the idea of magnetic non-contact retraction using surface ferromagentization. We discuss the current limitations, the future potential of MAG-ESD and the developments needed for adoption of this technology.

关键词： Endoscopic submucosal dissection Gastric cancer Magnetic anchor guidance Esophageal cancer Magnets Traction Natural orifice transluminal endoscopic surgery

Gas Line Pressure Fluctuation Analysis of a Gas-Liquid Reactor

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journal of Thermal Science 2005年第3期14卷 267-271页

作者： j.j.j. cHEN j.c. ZHAO chemical & Materials Engineering Department The University of Auckland Private Bag 92019 Auckland New Zealand ProfessorChemical & Materials Engineering Department The University of Auckland Private Bag 92019 Auckland New Zealand

To ensure efficient operation of metallurgical gas-liquid reactors, the gas bubbles must be uniformly distributed. For high temperature metallurgical reactors, it is impractical and unsafe to carry out visual observations. An air-water model was used to study the relationship between the bubble flow patterns and the pressure fluctuation signals. The fluctuation signals captured in the time domain were transformed into the frequency domain. Various parameters obtained from the transformed data were analysed for their suitability for delineating the bubble flow patterns observed. These parameters and the flow patterns were found to be well-correlated using the gas flow number.

关键词： gas liquid reactors bubble distribution signal analysis

Vibration control of fluid-conveying pipes: a state-of-the-art review

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Applied Mathematics and Mechanics(English Edition) 2023年第9期44卷 1423-1456页

作者： Hu DING j.c.jI Shanghai Key Laboratory of Mechanics in Energy Engineering School of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China Shaoxing Institute of Technology Shanghai UniversityShaoxing 312074Zhejiang ProvinceChina Shanghai Institute of Aircraft Mechanics and control Shanghai 200092China School of Mechanical and Mechatronic Engineering University of Technology SydneyNew South Wales 2007Australia

Fluid-conveying pipes are widely used to transfer bulk fluids from one point to another in many engineering *** are subject to various excitations from the conveying fluids,the supporting structures,and the working environment,and thus are prone to vibrations such as flow-induced vibrations and acoustic-induced *** can generate variable dynamic stress and large deformation on fluid-conveying pipes,leading to vibration-induced fatigue and damage on the pipes,or even leading to failure of the entire piping system and catastrophic ***,the vibration control of fluid-conveying pipes is essential to ensure the integrity and safety of pipeline systems,and has attracted considerable attention from both researchers and *** present paper aims to provide an extensive review of the state-of-the-art research on the vibration control of fluid-conveying *** vibration analysis of fluid-conveying pipes is briefly discussed to show some key issues involved in the vibration ***,the research progress on the vibration control of fluid-conveying pipes is reviewed from four aspects in terms of passive control,active vibration control,semi-active vibration control,and structural optimization design for vibration ***,the main results of existing research on the vibration control of fluid-conveying pipes are summarized,and future promising research directions are recommended to address the current research *** paper contributes to the understanding of vibration control of fluid-conveying pipes,and will help the research work on the vibration control of fluidconveying pipes attract more attention.

关键词： fuid-conveying pipe vibration passive control nonlinear energy sink(NES) active control semi-active control

Dynamic Mechanical Relaxation in Bulk Metallic Glasses:A Review

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journal of Materials Science & Technology 2014年第6期30卷 523-545页

作者： j.c.Qiao j.M.Pelletier Université de Lyon CNRS France INSA-Lyon MATEIS UMR5510 F-69621 Villeurbanne France

Metallic glasses have aroused considerable interest in the past decades because they exhibit fascinating properties. First, this article briefly outlines the mechanical, thermal properties and application of the metallic glasses. In addition, we focus on the dynamic mechanical relaxation behaviors, i.e. main （α） and secondary （β） relaxations, in metallic glasses. The mechanical relaxation behaviors are connected to the mechanical properties and physical properties in glassy materials. The main relaxation in glassy materials is related to the glass transition phenomenon and viscous flow. On the other hand, the β relaxation is linked to many fundamental issues in metallic glasses. In these materials relaxation processes are directly related to the plastic deformation mechanism. The mechanical relaxations, particularly, the β relaxation provides an excellent opportunity to design metallic glasses with desired physical and mechanical properties. We demonstrate the universal characteristics of main relaxation in metallic glasses. The phenomenological models and the physical theories are introduced to describe the main relaxation in metallic glasses. In parallel, we show the dependence of the α. and β relaxations on the thermal treatments in metallic glasses. Finally, we analyze the correlation between the atomic mobility and the thermo-mechanical treatments in metallic glasses. On the one hand, the atomic mobility in metallic glasses is reduced by physical aging or crystallization. On the other hand, the atomic mobility in metallic glass is enhanced by deformation （i.e. compression and cold rolling）. Importantly, to analyze the atomic mobility in amorphous materials, a physical theory is introduced. This model invokes the concept of quasi-point defects, which correspond to the density fluctuations in the glassy materials.

关键词： Metallic glasses Mechanical properties Main relaxation Secondary relaxation Physical analysis

The Kirkendall effect on erosion resistance of chrome-coated 25cr3Mo2WNiV and 30SiMn2MoV gun barrel steels

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journal of Materials Science & Technology 2024年第10期177卷 246-255页

作者： c.H.Dou P.F.jin c.Z.Wang j.j.Li c.Zhang j.F.Huang c.Zhang Key Laboratory for Advanced Materials Processing State State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China National joint Engineering Research center for Abrasion control and Molding of Metal Materials School of Materials Science and EngineeringHenan University of Science and TechnologyLuoyang 471003China

This study aimed to investigate the erosion behavior and mechanism of a newly developed 25cr3Mo2WNiV steel with a chrome coating using promoted ignition combustion *** erosion threshold pressure and temperature of the chrome-coated 25cr3Mo2WNiV steel were determined to be 0.2 MPa and 254.3 K higher than those of traditional chrome-coated 30SiMn2MoV ***,Kirkendall voids and inter-diffusion between the cr coating and matrix were first observed before *** improved erosion resistance of the chrome-coated 25cr3Mo2WNiV steel was attributed to the suppression of the Kirkendall effect,which minimized heat generation at the cr/matrix interface by pre-venting oxygen diffusion and reducing oxygen affinity.

关键词： Erosion resistance Kirkendall effect cr coating Gun steel

cONTINUUM VOID NUcLEATION MODEL FOR Al-Mg ALLOY SHEET BASED ON MEASURED PARTIcLE DISTRIBUTION

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Acta Mechanica Solida Sinica 2009年第5期22卷 391-398页

作者： c.j.Butcher Department of Mechanical Engineering University of New BrunswickFrederictonNBCanadaE 3B 5A3

Void nucleation within measured particle fields of an aluminum alloy is investigated to develop a continuum nucleation model which reflects nucleation at the individual particle scale. A nucleation model for heterogeneous particle distributions is synchronized with the continuum model of chu and Needleman using the average nucleation strain. The parameters in the continuum model are identified from the particle fields and are evaluated over the range of stress states observed in sheet metal forming. The synchronized continuum nucleation model achieves very good agreement with the nucleation trends for three measured particle fields in uniaxial tension, plane strain, and equal-biaxial tension.

关键词： void nucleation ductile fracture second-phase particles aluminum