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Nontraditional energy-assisted mechanical machining of difficult-to-cut materials and components in aerospace community:a comparative analysis

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International Journal of Extreme Manufacturing 2024年第2期6卷 190-271页

作者： Guolong zhao biao zhao Wenfeng Ding Lianjia Xin Zhiwen Nian Jianhao Peng Ning He Jiuhua Xu College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

The aerospace community widely uses difficult-to-cut materials,such as titanium alloys,high-temperature alloys,metal/ceramic/polymer matrix composites,hard and brittle materials,and geometrically complex components,such as thin-walled structures,microchannels,and complex surfaces.Mechanical machining is the main material removal process for the vast majority of aerospace components.However,many problems exist,including severe and rapid tool wear,low machining efficiency,and poor surface integrity.Nontraditional energy-assisted mechanical machining is a hybrid process that uses nontraditional energies(vibration,laser,electricity,etc)to improve the machinability of local materials and decrease the burden of mechanical machining.This provides a feasible and promising method to improve the material removal rate and surface quality,reduce process forces,and prolong tool life.However,systematic reviews of this technology are lacking with respect to the current research status and development direction.This paper reviews the recent progress in the nontraditional energy-assisted mechanical machining of difficult-to-cut materials and components in the aerospace community.In addition,this paper focuses on the processing principles,material responses under nontraditional energy,resultant forces and temperatures,material removal mechanisms,and applications of these processes,including vibration-,laser-,electric-,magnetic-,chemical-,advanced coolant-,and hybrid nontraditional energy-assisted mechanical machining.Finally,a comprehensive summary of the principles,advantages,and limitations of each hybrid process is provided,and future perspectives on forward design,device development,and sustainability of nontraditional energy-assisted mechanical machining processes are discussed.

关键词： difficult-to-cut materials geometrically complex components nontraditional energy mechanical machining aerospace community

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Bayesian Filtering for High-Dimensional State-Space Models With State Partition and Error Compensation

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1239-1249页

作者： Ke Li Shunyi zhao biao Huang Fei Liu Key Laboratory of Advanced Process Control for Light Industry(Ministry of Education) Institute of AutomationJiangnan UniversityWuxi 214122China Department of Chemical and Materials Engineering University of AlbertaEdmonton AB T6G 2G6Canada

In the era of exponential growth of data availability,the architecture of systems has a trend toward high dimensionality,and directly exploiting holistic information for state inference is not always computationally affordable.This paper proposes a novel Bayesian filtering algorithm that considers algorithmic computational cost and estimation accuracy for high-dimensional linear systems.The high-dimensional state vector is divided into several blocks to save computation resources by avoiding the calculation of error covariance with immense dimensions.After that,two sequential states are estimated simultaneously by introducing an auxiliary variable in the new probability space,mitigating the performance degradation caused by state segmentation.Moreover,the computational cost and error covariance of the proposed algorithm are analyzed analytically to show its distinct features compared with several existing methods.Simulation results illustrate that the proposed Bayesian filtering can maintain a higher estimation accuracy with reasonable computational cost when applied to high-dimensional linear systems.

关键词： filtering estimation error

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Quantum nonlocality evolution for two entangled mesoscopic fields under decoherence

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Communications in Theoretical Physics 2024年第1期76卷 24-28页

作者： zhao-Song Tan Shou-Bang Yang Zhen-biao Yang Shi-biao Zheng Fujian Key Laboratory of Quantum Information and Quantum Optics Fuzhou UniversityFuzhouFujian 350116China

Investigation of the nonlocality evolution of entangled mesoscopic fields under decoherence not only is important for understanding the quantum–classical transition,but also has relevance to quantum communication and quantum computation protocols based on continuous variables.According to previous formulations of Bell inequalities,the system loses nonlocal features far before the disappearance of entanglement.We here construct a new version of Bell signal based on rotated and displaced on–off correlations,with which the Bell inequality is violated as long as there remains entanglement and the field state components keep quasiorthogonal.Consequently,the nonlocal character revealed by our formulation decays much slower compared with those based on previous ones.More importantly,there exists a wide regime where the Bell inequality is restored with previous formulations but remains to be violated based on our correlation operators.

关键词： entangled mesoscopic fields rotated and displaced on-off correlations Bell inequality nonlocality evolution

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Exploring the impacts of major events on the systemic risk of the international energy market

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Petroleum Science 2024年第2期21卷 1444-1457页

作者： Ming-Tao zhao Su-Wan Lu Lian-biao Cui School of Statistics and Applied Mathematics Anhui University of Finance and EconomicsBengbu233030AnhuiChina Anhui Province Key Laboratory of Philosophy and Social Science of Low-Carbon Development and Carbon Finance Anhui University of Finance and EconomicsBengbu233030AnhuiChina

This study examines the systemic risk caused by major events in the international energy market(IEM)and proposes a management strategy to mitigate it. Using the tail-event driven network(TENET)method, this study constructed a tail-risk spillover network(TRSN) of IEM and simulated the dynamic spillover tail-risk process through the cascading failure mechanism. The study found that renewable energy markets contributed more to systemic risk during the Paris Agreement and the COVID-19pandemic, while fossil energy markets played a larger role during the Russia-Ukraine conflict. This study identifies systemically important markets(SM) and critical tail-risk spillover paths as potential sources of systemic risk. The research confirms that cutting off the IEM risk spillover path can greatly reduce systemic risk and the influence of SM. This study offers insights into the management of systemic risk in IEM and provides policy recommendations to reduce the impact of shock events.

关键词： International energy market Tail-risk spillover Cascading failure mechanism Systemic risk management

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Seismic safety assessment with non-Gaussian random processes for train-bridge coupled systems

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 241-260页

作者： zhao Han Gao Lei Wei biao Tan Jincheng Guo Peidong Jiang Lizhong Xiang Ping Key Laboratory of Geomechanics and Embankment Engineering of Ministry of Education Hohai UniversityNanjing 210024China School of Civil Engineering Central South UniversityChangsha 410075China

Extensive high-speed railway(HSR)network resembled the intricate vascular system of the human body,crisscrossing mainlands.Seismic events,known for their unpredictability,pose a significant threat to both trains and bridges,given the HSR’s extended operational duration.Therefore,ensuring the running safety of train-bridge coupled(TBC)system,primarily composed of simply supported beam bridges,is paramount.Traditional methods like the Monte Carlo method fall short in analyzing this intricate system efficiently.Instead,efficient algorithm like the new point estimate method combined with moment expansion approximation(NPEM-MEA)is applied to study random responses of numerical simulation TBC systems.Validation of the NPEM-MEA’s feasibility is conducted using the Monte Carlo method.Comparative analysis confirms the accuracy and efficiency of the method,with a recommended truncation order of four to six for the NPEM-MEA.Additionally,the influences of seismic magnitude and epicentral distance are discussed based on the random dynamic responses in the TBC system.This methodology not only facilitates seismic safety assessments for TBC systems but also contributes to standard-setting for these systems under earthquake conditions.

关键词： train-bridge coupled(TBC)system random vibration new point estimate method(NPEM) seismic safety assessment moment expansion approximation(MEA) non-Gaussian distributions

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Multiple paradoxical embolisms caused by central venous catheter thrombus passing through a patent foramen ovale: A case report

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World Journal of Clinical Cases 2024年第4期12卷 842-846页

作者： Jian-Duan Li Nian Xu Qiang zhao biao Li Li Li Department of Cardiology Guangzhou Red Cross Hospital of Jinan UniversityGuangzhou 510235Guangdong ProvinceChina

BACKGROUND To date,this is the first case of a paradoxical embolism(PDE)that concurrently manifested in the coronary and lower limb arteries and was secondary to a central venous catheter(CVC)thrombus via a patent foramen ovale(PFO).CASE SUMMARY Here,we report a case of simultaneous coronary and lower limb artery embolism in a PFO patient carrier of a CVC.The patient presented to the hospital with acute chest pain and lower limb fatigue.Doppler ultrasound showed a large thrombus in the right internal jugular vein,precisely at the tip of the CVC.Transthoracic and transesophageal echocardiography confirmed the existence of a PFO,with inducible right-to-left shunting by the Valsalva maneuver.The patient was administered an extended course of anticoagulation therapy,and then the CVC was successfully removed.Percutaneous PFO closure was not undertaken.There was no recurrence during follow-up.CONCLUSION Thus,CVC-associated thrombosis is a potential source for multiple PDE in PFO patients.

关键词： Paradoxical embolism Central venous catheter Patent foramen ovale Acute myocardial infarction Case report

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Design strategies of high-performance lead-free electroceramics for energy storage applications

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Rare Metals 2024年第3期43卷 853-878页

作者： biao Guo Fei Jin Li Li Zi-zhao Pan Xin-Wei Xu Hong Wang Department of Materials Science and Engineering College of EngineeringSouthern University of Science and TechnologyShenzhen518055China School of Microelectronics and State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an710049China

A greater number of compact and reliable electrostatic capacitors are in demand due to the Internet of Things boom and rapidly growing complex and integrated electronic systems,continuously promoting the development of high-energy-density ceramic-based capacitors.Although significant successes have been achieved in obtaining high energy densities in lead-based ferroelectric ceramics,the utilization of lead-containing ceramies has been restricted due to environmental and health hazards of lead.Lead-free ferroelectric ceramics have garnered tremendous attention and are expected to replace lead-based ceramics in the near future.However,the energy density of lead-free ceramics is still lagging behind that of lead-containing cou.nterparts,severely limiting their applications.Significant efforts have been made to enhance the energy storage performance of lead-free ceramics using multi-scale design strategies,and exciting progress has been achieved in the past decade.This review briefly discusses the energy storage mechanism and fundamental characteristics of a dielectric capacitor,summarizes and compares the state-of-the-art design strategies for high-energy-density lead-free ceramics,and highlights several critical issues and requirements for industrial production.The prospects and challenges of lead-free ceramics for energy storage applications are also discussed.

关键词： Dielectric materials Lead-free ceramic Environment friendly Energy storage Design strategy

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Intrinsic mechanism and multiphysics analysis of electromagnetic wave absorbing materials: New horizons and breakthrough

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Journal of Materials Science & Technology 2022年第35期130卷 136-156页

作者： Long Xia Yuming Feng biao zhao School of Materials Science and Engineering Harbin Institute of Technology at WeihaiWeihai 264209China School of Microelectronics Fudan UniversityShanghai 200433China

Electromagnetic absorbers(EMA) have driven the development of Electromagnetic(EM) technology and advanced EM devices. Utilizing the EM energy conversion of EM absorbers to design various devices is attractive and promising, especially in personal protection and healthcare. In this review article, the simulation and numerical analysis of EM materials are reviewed, from numerical analysis of dielectric parameters, simulation of wave absorbing performance, electromagnetic performance improvement, and structural construction optimization. For the EM response mechanism, radiation-dependent relaxation and charge transport energy transitions are dissected. For the EM calculation section, two leading roles are highlighted, including the purposeful design of EM and the provision of theoretical guidance for optimizing electromagnetic absorption performance. In addition, this work points out the current problems and potential opportunities in the numerical simulation of absorbing materials, points out the new development direction, and proposes prospects.

关键词： Microwave absorption Multiphysics simulation Dielectric parameters EMA Properties optimization

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Low-dimensional cobalt doped carbon composite towards wideband electromagnetic dissipation

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Nano Research 2023年第1期16卷 70-79页

作者： Xiaodi Zhou biao zhao Hualiang Lv School of Microelectronics Fudan UniversityShanghai 200433China Willian G.Lowrie Department of Chemical and Biomolecular Engineering The Ohio State UniversityColumbusOH 43210USA

Composites composed of a carbon matrix decorated with a metal or metal oxide derived from zeolitic imidazolate frameworks(ZIFs)have been widely applied as suitable electromagnetic wave absorbers due to their high porosity and controllable morphology.However,achieving ideal absorption performance remains a challenge owing to the inadequate conductivity and high density of the metal components.Therefore,a temperature-controlling treatment was employed for the bimetal ZIFs,and the corresponding derivatives exhibited an excellent dissipation ability with a minimum reflection loss value of−54.3 dB and an effective bandwidth of 7.0 GHz at a thickness of 2.4 mm,which resulted from the strong dipole polarization behavior.Furthermore,after successfully controlling the Zn/Co ratio,the attenuation capability was greatly enhanced at a thickness of 1.4 mm,with bandwidths of 13.0–18.0 GHz.Overall,this work provides an ameliorated strategy for microwave absorption performance of carbon-based materials.

关键词： microwave absorption bi-meta based absorber single-atom metal organic frameworks(MOFs)derived composite dielectric relaxation

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Long-term tadalafil once daily in Chinese men witherectile dysfunction:a 2-year final analysis of apost-marketing,multicenter,randomized,open-labeltrial

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Asian Journal of Andrology 2024年第3期26卷 282-287页

作者： Hui Jiang Lian-Ming zhao Su Yan Ji-Hong Liu zhao-Hui Zhu Jin-Dan Luo Yu-Tian Dai Fu-biao Li Hao-Cheng Lin Zhi-Chao Zhang Department of Urology Peking University First HospitalBeijing 100000China Department of Urology Peking University Third HospitalBeijing 100191China Department of Urology Peking Union Medical College HospitalBeijing 100730China Department of Urology Tongji HospitalTongji Medical CollegeHuazhongUniversity of Science and TechnologyWuhan 430030China Department of Urology Union Hospital of Tongji Medical CollegeHuazhong University of Science andTechnologyWuhan 430022China Department of Urology The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Departmentof Andrology Nanjing Drum Tower HospitalNanjing 210008China Department of Andrology The First Hospital of Jilin UniversityChangchun 130021China Andrology Center Department of UrologyPeking University First HospitalBeijing 100034China.

The long-term safety and effectiveness of once-daily tadalafil is crucial,but limited data are available in Chinese patients witherectile dysfunction(ED).In this post-marketing,multicenter,randomized,open-label trial with 2-year follow-up,635 ED caseswere randomized to receive daily oral tadalafil 2.5 mg or 5 mg for 3 months,of whom 580 continued once-daily tadalafil 5 mg for21 months.Treatment-emergent adverse events in the 12-month and 24-month period were similar,with the most common beingviral upper respiratory tract infection,upper respiratory tract infection,and headache.Significant improvement from baseline inthe International Index of Erectile Function-Erectile Function(IIEF-EF)score was detected at month 12(least squares mean[LSM]change:7.9,95%confidence interval[CI]:7.5–8.4,P<0.001)and was maintained to month 24(LSM change:8.6,95%CI:8.1–9.0,P<0.001).The proportions of patients regaining normal erectile function(IIEF-EF score≥26)were 43.7%and 48.0%at months 12 and 24,respectively.Global Assessment Questionnaire results showed improved erection function in 97.5%ofpatients and improved ability to engage in sexual activity in 95.9%of patients at month 12;these values were 96.1%and 95.0%at month 24,respectively.The quality of sexual life score based on the Sexual Life Quality Questionnaire(SLQQ)was increased by52.2%at month 12 and by 55.3%at month 24(both P<0.001).The treatment satisfaction score determined by SLQQ(mean±standard deviation)was 62.4±21.0 at month 12 versus 65.9±20.2 at month 24.Two-year daily application of tadalafil 5mg in Chinese men with ED showed a favorable safety profile and durable improvement in sexual performance and satisfaction.

关键词： clinical trial erectile dysfunction long-term safety once-daily dosing tadalafil

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