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Conventional and micro scale finite element modeling for metal cutting process:A review

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Chinese Journal of Aeronautics 2024年第2期37卷 199-232页

作者： Le WANG Caixu yUE Xianli LIU Ming LI yongshi XU Steven y.LIANG Key Laboratory of Advanced Manufacturing and Intelligent Technology Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlanta 30332USA

The metal cutting process is accompanied by complex stress field,strain field,temperature *** comprehensive effects of process parameters on chip morphology,cutting force,tool wear and residual stress are complex and *** element method(FEM)is considered as an effective method to predict process variables and reveal microscopic physical phenomena in the cutting ***,the finite element(FE)simulation is used to research the conventional and micro scale cutting process,and the differences in the establishment of process variable FE simulation models are distinguished,thereby improving the accuracy of FE *** reliability and effectiveness of FE simulation model largely depend on the accuracy of the simulation method,constitutive model,friction model,damage model in describing mesh element,the dynamic mechanical behavior of materials,the tool-chip-workpiece contact process and the chip formation *** this paper,the FE models of conventional and micro process variables are comprehensively and up-to-date reviewed for different materials and machining *** purpose is to establish a FE model that is more in line with the real cutting conditions,and to provide the possibility for optimizing the cutting process *** development direction of FE simulation of metal cutting process is discussed,which provides guidance for future cutting process modeling.

关键词： Conventional and micro scale Finite element simulation Metal cutting process Micro cutting Modeling

A particle-resolved heat-particle-fluid coupling model by DEM-IMB-LBM

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2267-2281页

作者： Ming Xia Jinlong Fu y.T.Feng Fengqiang Gong Jin yu Hunan Key Laboratory of Geomechanics and Engineering Safety Xiangtan UniversityXiangtan411105China Zienkiewicz Institute for Modelling Data and AISwansea UniversitySwanseaSA18EPUK School of Civil Engineering Southeast UniversityNanjing211189China Fujian Research Center for Tunneling and Urban Underground Space Engineering Huaqiao UniversityXiamen361021China

Multifield coupling is frequently encountered and also an active area of research in geotechnical *** this work,a particle-resolved direct numerical simulation(PR-DNS)technique is extended to simulate particle-fluid interaction problems involving heat transfer at the grain *** this extended technique,an immersed moving boundary(IMB)scheme is used to couple the discrete element method(DEM)and lattice Boltzmann method(LBM),while a recently proposed Dirichlet-type thermal boundary condition is also adapted to account for heat transfer between fluid phase and solid *** resulting DEM-IBM-LBM model is robust to simulate moving curved boundaries with constant temperature in thermal *** facilitate the understanding and implementation of this coupled model for non-isothermal problems,a complete list is given for the conversion of relevant physical variables to lattice ***,benchmark tests,including a single-particle sedimentation and a two-particle drafting-kissing-tumbling(DKT)simulation with heat transfer,are carried out to validate the accuracy of our coupled *** further investigate the role of heat transfer in particle-laden flows,two multiple-particle problems with heat transfer are *** examples demonstrate that the proposed coupling model is a promising high-resolution approach for simulating the heat-particle-fluid coupling at the grain level.

关键词： Particle-fluid interaction Heat transfer Discrete element method(DEM) Lattice Boltzmann method(LBM) Dirichlet-type thermal boundary Direct numerical simulation

Optimal Coordination of Transportable Power Sources and Repair Crews for Service Restoration of Distribution Networks Considering Uncertainty of Traffic Congestion

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 189-201页

作者： Zhao Shi yan Xu Dunjian Xie Shiwei Xie Amer M.y.M.Ghias Nanyang Technological University Singapore the School of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108China

This paper proposes a new method for service restoration of distribution network with the support of transportable power sources(TPSs)and repair crews(RCs).Firstly,a coupling model of distribution networks and vehicle routing of TPSs and RCs is proposed,where the TPSs serve as emergency power supply sources,and the RCs are used to repair the faulted *** the uncertainty of traffic congestion,the probability distribution of the travel time spent on each road is derived based on the Nesterov user equilibrium model,and a two-stage stochastic program is formulated to determine the optimal routings of TPSs and *** efficiently solve the proposed stochastic mixed-integer linear program(MILP),a two-phase scenario reduction method is then developed to scale down the problem size,and an adaptive progressive hedging algorithm is used for an efficient *** effectiveness of the proposed methods and algorithms has been illustrated in a modified IEEE 33-bus system.

关键词： Service restoration distribution network traffic uncertainty transportable power source repair crew stochastic program

Challenges and opportunities for battery health estimation:Bridging laboratory research and real-world applications

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Journal of Energy Chemistry 2024年第2期89卷 434-436,I0011页

作者： Te Han Jinpeng Tian C.y.Chung yi-Ming Wei Center for Energy and Environmental Policy Research Beijing Institute of TechnologyBeijing 100081China School of Management and Economics Beijing Institute of TechnologyBeijing 100081China Department of Electrical and Electronic Engineering and Research Centre for Grid Modernization The Hong Kong Polytechnic UniversityKowloon 999077Hong KongChina

Addressing climate change demands a significant shift away from fossil fuels,with sectors like electricity and transportation relying heavily on renewable *** to this transition are energy storage systems,notably lithium-ion *** time,these batteries degrade,affecting their efficiency and posing safety *** and predicting battery aging is essential,especially estimating its state of health(SOH).Various SOH estimation methods exist,from traditional model-based approaches to machine learning approaches.

关键词： Energy storage systems State of health Multi-source data Scientific AI Data-sharing mechanism

Concordance among pulse wave velocity assessment methods: A network meta-analysis

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中华医学杂志(英文版) 2024年第17期137卷 2137-2139页

作者： Cavero-Redondo Iván Sequí-Domínguez Irene Saz-Lara Alicia Garcia-Klepzig Jose Luis Lucerón-lucas-Torres Maribel Martínez-García Irene álvarez-Bueno Celia Martínez-Vizcaíno Vicente CarVasCare Research Group Facultad de Enfermería de Cuenca Universidad de Castilla-La Mancha Cuenca Spain Facultad de Ciencias de la Salud Universidad Autónoma de Chile Talca Chile Health and Social Research Center Universidad de Castilla-La Mancha Cuenca Spain Internal Medicine Department San Carlos University Hospital Madrid Spain Universidad Politécnica y Artística del Paraguay Asunción Paraguay

Hypercoagulable state and risk of venous thromboembolism in Cushing syndrome

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Zhong nan da xue xue bao. yi xue ban = Journal of Central South University. Medical sciences 2024年第6期49卷 825-831页

作者： Liu y. Tang y. Tan H. Li J. Department of Endocrinology and Metabolism Center of Pituitary Adenoma and Related Diseases West China Hospital Sichuan University Chengdu 610041 China

库欣综合征(Cushing syndrome，CS)是以高皮质醇血症为特征的内分泌代谢疾病，高皮质醇血症可诱发高凝状态，导致静脉血栓栓塞(venous thromboembolism，VTE)风险增加。无论是垂体来源的库欣病(Cushing disease，CD)，还是肾上腺来源的... 详细信息

库欣综合征(Cushing syndrome，CS)是以高皮质醇血症为特征的内分泌代谢疾病，高皮质醇血症可诱发高凝状态，导致静脉血栓栓塞(venous thromboembolism，VTE)风险增加。无论是垂体来源的库欣病(Cushing disease，CD)，还是肾上腺来源的非促肾上腺皮质激素(adrenocorticotropic hormone，ACTH)依赖性CS，手术均是一线治疗选择。在手术和疾病本身的双重影响下，VTE风险进一步增加，甚至导致肺栓塞，严重威胁患者生命安全。此外，高凝状态的CS患者的心血管病和VTE发生率乃至病死率均高于正常人群，未经治疗的活动性CS患者的VTE发生率较普通人群升高了17.8倍。近年来，CS高凝状态与VTE之间的关系引起了越来越多临床医师的重视。进一步了解CS高凝状态的临床流行病学特点、病理生理机制和VTE及肺栓塞的临床防治，可以为CS患者预防性抗凝药物规范化使用提供参考。.; Cushing syndrome (CS) is an endocrine-metabolic disorder characterized by hypercortisolism. Elevated cortisol levels can induce a hypercoagulable state, increasing the risk of venous thromboembolism (VTE). Both pituitary-origin Cushing disease (CD) and adrenal-origin non-adrenocorticotropic hormone (ACTH)-dependent CS are primarily treated with surgery. The dual impact of surgery and the underlying disease further elevates the risk of VTE, potentially leading to pulmonary embolism, which poses a severe threat to patient survival. Additionally, CS patients in a hypercoagulable state have a higher incidence of cardiovascular diseases and VTE, and even mortality compared with the general population. Untreated active CS patients have a 17.8-fold increased risk of VTE compared to the general population. In recent years, the relationship between the hypercoagulable state in CS and VTE has garnered increasing attention from clinicians. A better understanding of the clinical epidemiological characteristics, pathophysiological mechanisms, and clinical prevention and treatment of VTE and pulmonary embolism in CS can provide valuable references for the standardized use of prophylactic anticoagulant therapy in CS patients.

关键词： Cushing syndrome hypercoagulable state venous thromboembolism

A holistic approach to improving safety for battery energy storage systems

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Journal of Energy Chemistry 2024年第5期92卷 422-439页

作者： James Close Jonathan E.Barnard y.M.John Chew Semali Perera Department of Chemical Engineering Centre for DigitalManufacturing&DesignUniversity of BathBath BA27AYUK ioMosaic International Limited 16-18 Queen SquareBath BA12HNUK

The integration of battery energy storage systems(BESS)throughout our energy chain poses concerns regarding safety,especially since batteries have high energy density and numerous BESS failure events have *** spread adoption will only increase the prevalence of these failure events unless there is a step change in the management and design of *** understand the causes of failure,the main challenges of BESS safety are *** consequences and failure events are discussed,including specific focus on the chain of events causing thermal runaway,and a case study of a BESS explosion in Surprise Arizona is *** on the technology and past events,a paradigm shift is required to improve BESS *** this review,a holistic approach is *** combines currently adopted approaches including battery cell testing,lumped cell mathematical modelling,and calorimetry,alongside additional measures taken to ensure BESS safety including the requirement for computational fluid dynamics and kinetic modelling,assessment of installation level testing of the full BESS system and not simply a single cell battery test,hazard and layers of protection analysis,gas chromatography,and composition *** holistic approach proposed in this study aims to address challenges of BESS safety and form the basis of a paradigm shift in the safety management and design of these systems.

关键词： Energy storagesystems Process safety Battery safety Thermal safety

MAVEN observation of magnetosonic waves in the Martian magnetotail region

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Earth and Planetary Physics 2024年第2期8卷 317-325页

作者： ShangChun Teng JiCheng Sun JiaWei Gao y.Harada Markus Fraenz DeSheng Han State Key Laboratory of Marine Geology School of Ocean and Earth ScienceTongji UniversityShanghai 200092China MNR Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Geophysics Kyoto UniversityKyotoJapan Max-Planck-Institute for Solar System Research GoettingenGermany

Magnetosonic waves are an important medium for energy transfer in collisionless space *** waves have been widely investigated in the upstream of the bow shock at *** waves are believed to originate from pickup ions or reflected *** utilizing MAVEN spacecraft data,we have observed the occurrence of quasi-perpendicularly propagating magnetosonic emissions near the proton gyrofrequency in the Martian magnetotail *** plasma waves are associated with a significant enhancement of proton and oxygen *** excited magnetosonic waves could possibly heat the protons through resonance and facilitate the ionospheric plasma *** results could be helpful to better understand the Mars’magnetospheric dynamics and offer insights into possible energy redistribution between waves and plasma in the Martian nightside magnetosphere.

关键词： Martian magnetotail region magnetosonic waves proton escape

Seminoma characterized by thickening of the pituitary stalk: A case report

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Zhong nan da xue xue bao. yi xue ban = Journal of Central South University. Medical sciences 2024年第6期49卷 863-869页

作者： Peng B. Wang X. Deng y. Lian y. Zheng y. Kuang J. Qian J. Liang J. Zhang y. Department of Endocrinology First Affiliated Hospital of Army Medical University 400038 Chongqing China Department of Radiology First Affiliated Hospital of Army Medical University 400038 Chongqing China Department of Endocrinology 958th Hospital of the Chinese People's Liberation Army 400020 Chongqing China Department of Neurosurgery First Affiliated Hospital of Army Medical University 400038 Chongqing China

颅内精原细胞瘤是一种罕见的起源于生殖细胞系的恶性肿瘤，通常发生在脑部的松果体或垂体等部位。陆军军医大学第一附属医院内分泌科于2020年6月收治１例颅内精原细胞瘤伴脊柱转移的20岁男性患者，临床表现为头痛、头晕及视力下降，头... 详细信息

颅内精原细胞瘤是一种罕见的起源于生殖细胞系的恶性肿瘤，通常发生在脑部的松果体或垂体等部位。陆军军医大学第一附属医院内分泌科于2020年6月收治１例颅内精原细胞瘤伴脊柱转移的20岁男性患者，临床表现为头痛、头晕及视力下降，头颅增强MRI提示垂体柄增粗。在多学科综合会诊后接受经鼻蝶鞍区肿瘤切除术，病理诊断为精原细胞瘤，术后规律放射治疗。1年后患者的肿瘤复发并转移，再次行胸椎椎管内肿瘤切除术，术后继续化学治疗。患者的临床症状如头痛和视力障碍得到改善，但持续全垂体功能减退，需长期激素替代。颅内精原细胞瘤的早期诊断颇具挑战性，且易发生转移，对放射治疗和化学治疗高度敏感，早期诊断和多学科综合治疗有助于改善患者的生活质量和预后。.; Intracranial seminoma is a rare malignant tumor originating from the germ cells, usually occurring in the pineal gland or pituitary gland. In June 2020, the Department of Endocrinology at the First Affiliated Hospital of Army Military Medical University admitted a 20-year-old male patient with an intracranial germ cell tumor and spinal metastases. The patient presented with headache, dizziness, and visual impairment. Enhanced magnetic resonance imaging (MRI) of the head indicated thickening of the pituitary stalk. After multidisciplinary consultation, the patient underwent endonasal transsphenoidal resection of the tumor, with the pathological diagnosis confirming germ cell tumor. The patient received regular radiotherapy postoperatively. One year later, the tumor recurred and metastasized, leading to a second surgery for tumor resection in the thoracic spinal canal, followed by continued chemotherapy. The patient's clinical symptoms, such as headache and visual disturbances, improved, but he continued to experience panhypopituitarism and required long-term hormone replacement therapy. Early diagnosis of intracranial germ cell tumors is challenging, and they are prone to metastasis and highly sensitive to radiotherapy and chemotherapy. Early diagnosis and multidisciplinary comprehensive treatment can help improve the quality of life and prognosis for patients.

关键词： immunohistochemistry intracranial seminoma magnetic resonance imaging surgery