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Machine learning-based direct solver for one-to-many problems on temporal shaping of relativistic electron beams

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Frontiers of physics 2022年第6期17卷 15-24页

作者： Jinyu wan yi Jiao Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China China Spallation Neutron Source Dongguan 523803China

To control the temporal profile of a relativistic electron beam to meet requirements of various advanced scientific applications like free-electronlaser and plasma wakefield acceleration,a widely-used technique is to manipulate the dispersion terms which turns out to be one-to-many *** to their intrinsic one-to-many property,current popular stochastic optimization approaches on temporal shaping may face the problems of long computing time or sometimes suggesting only one *** we propose a real-time solver for one-to-many problems of temporal shaping,with the aid of a semi-supervised machine learning method,the conditional generative adversarial network(CGAN).We demonstrate that the CGAN solver can learn the one-to-many dynamics and is able to accurately and quickly predict the required dispersion terms for different custom temporal *** machine learning-based solver is expected to have the potential for wide applications to one-to-many problems in other scientific fields.

关键词： beam shaping one-to-many problem machine learning

Light People:*** Bowers spoke about silicon photonics

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Light(Science & Applications) 2022年第12期11卷 2843-2848页

作者： Chenzi Guo yating wan Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchunChina Integrated Photonics lab King Abdullah University of Science and TechnologyThuwalMakkah

Editorial Silicon photonics is advancing rapidly with many scientific and engineering advances and many new applications for *** highlight the topic,Light:Science&Applications invited John Bowers,director of the Institute for Energy Efficiency and distinguished professor from the University of California,Santa Barbara,to talk about the fundamentals and industries,and give a future perspective of silicon *** below is summarized from the video interview of *** original interview can be accessed in Supplementary video.

关键词： Efficiency interview photonics

A ruptured recurrent small bowel gastrointestinal stromal tumour causing hemoperitoneum

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Frontiers of Medicine 2015年第1期9卷 108-111页

作者： Eric C.H. Lai Kam Man Chung Stephanie H.y. Lau wan yee Lau Faculty of Medicine The Chinese University of Hong Kong Shatin Hong Kong SAR China Dr. K.M. Chung's Clinic Rm 807 Hang Seng Tsimshatsui Building 18 Carnarvon Road Tsimshatsui Hong Kong SAR China Department of Surgery Pamela Youde Nethersole Eastern Hospital Hong Kong SAR China Department of Surgery Queen Elizabeth Hospital Hong Kong SAR China

Hemoperitoneum is a rare and potentially life-threatening complication of GIST. We reported a 54- year-old man who developed disseminated intra-abdominal recurrence from a previously resected gastrointestinal stromal tumour （GIST） of the small bowel, and the patient presented with hemoperitoneum. Emergent debulking surgery was performed. A high dose imatinib was prescribed. Despite the presence of residual disease, the patient was well clinically 8 months after the operation. Even though, there is no evidence to support the routine use of debulking surgery in the management of GIST. In our patient, disease progression after second line targeted therapy and the absence of alternative treatment options for spontaneous rupture and hemoperitoneum prompted us to treat the patient aggressively. Resection of the ruptured GIST was carried out for control of bleeding and to prevent recurrent bleeding in this patient with good surgical risks. During the treatment decision-making, the patient＇s general condition, the risk of surgery and the extent of dissemination were taken into consideration. In this patient who presented with spontaneous rupture of a small intestinal GIST, the novel use of targeted therapy and aggressive surgical treatment produced reasonably good survival outcome.

关键词： gastrointestinal stromal tumour hemoperitoneum small bowel GIST small bowel neoplasm imatinib

Extracellular vesicle activities regulating macrophage- and tissue-mediated injury and repair responses

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Acta Pharmaceutica Sinica B 2021年第6期11卷 1493-1512页

作者： Qian Hu Christopher J.Lyon Jesse K.Fletcher Wenfu Tang Meihua wan Tony y.Hu Department of Integrated Traditional Chinese and Western Medicine West China HospitalSichuan UniversityChengdu 610041China Center of Cellular and Molecular Diagnosis Tulane University School of MedicineNew OrleansLA 70112USA Department of Biochemistry&Molecular Biology Tulane University School of MedicineNew OrleansLA 70112USA

Macrophages are typically identified as classically activated(M1) macrophages and alternatively activated(M2) macrophages,which respectively exhibit pro-and anti-inflammatory phenotypes,and the balance between these two subtypes plays a critical role in the regulation of tissue inflammation,injury,and repair *** studies indicate that tissue cells and macrophages interact via the release of small extracellular vesicles(EVs) in processes where EVs released by stressed tissue cells can promote the activation and polarization of adjacent macrophages which can in turn release EVs and factors that can promote cell stress and tissue inflammation and injury and vice *** review discusses the roles of such EVs in resulating such interactions to influence tissue inflammation and injury in a number of acute and chronic inflammatory disease conditions,and the potential applications,advantage and concerns for using EV-based therapeutic approaches to treat such conditions,including their potential role of drug carriers for the treatment of infectious diseases.

关键词： Extracellular vesicles Macrophage Tissue injury Inflammatory disease Interaction loop Stem cell Sepsis Targeted therapy

Numerical Modeling of a Spherical Buoy Moored by a Cable in Three Dimensions

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Chinese Journal of Mechanical Engineering 2016年第3期29卷 588-597页

作者： ZHU Xiangqian yOO wan-Suk Computer Aided Engineering Laboratory School of Mechanical Engineering Pusan National University

Floating facilities have been studied based on the static analysis of mooring cables over the past decades. To analyze the floating system of a spherical buoy moored by a cable with a higher accuracy than before, the dynamics of the cables are considered in the construction of the numerical modeling. The cable modeling is established based on a new element frame through which the hydrodynamic loads are expressed efficiently. The accuracy of the cable modeling is verified with an experiment that is conducted by a catenary chain moving in a water tank. In addition, the modeling of a spherical buoy is established with respect to a spherical coordinate in three dimensions, which can suffers the gravity, the variable buoyancy and Froude-Krylov loads. Finally, the numerical modeling for the system of a spherical buoy moored by a cable is established, and a virtual simulation is proceeded with the X- and y-directional linear waves and the X-directional current. The comparison with the commercial simulation code Proteus DS indicates that the system is accurately analyzed by the numerical modeling. The tensions within the cable, the motions of the system, and the relationship between the motions and waves are illustrated according to the defined sea state. The dynamics of the cables should be considered in analyzing the floating system of a spherical buoy moored by a cable.

关键词： numerical modeling dynamic simulation spherical buoy mooring cable dynamics of cable

Data-driven evaluation of fatigue performance of additive manufactured parts using miniature specimens

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Journal of Materials Science & Technology 2019年第6期35卷 1137-1146页

作者： H.y. wan G.F. Chen C.P. Li X.B. Qi G.P. Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China Materials Manufacturing Qualification Group Corporate Technology Siemens Ltd. China Beijing 100102 China State Key Laboratory of Tribology Tsinghua University Beijing J00084 China

This overview firstly introduces the state-of-the-art research progress in length scale-related fatigue performance of conventionally-fabricated metals evaluated by miniature specimens. Some key factors for size effects sensitive to microstructures including the specimen thickness, grain size and a ratio between them are highlighted to summarize some general rules for size effects. Then, ongoing research progress and new challenges in evaluating the fatigue performance of additive manufactured parts controlled by location-specific defects, microstructure heterogeneities as well as mechanical anisotropy using miniature specimen testing technique are discussed and addressed. Finally, a potential roadmap to establish a data-driven evaluation platform based on a large number of miniature specimen-based experiment data,theoretical computations and the ’big data’ analysis with machine learning is proposed. It is expected that this overview would provide a novel strategy for the realistic evaluation and fast qualification of fatigue properties of additive manufactured parts we have been facing to.

关键词： Additive manufacturing Miniature specimen Fatigue Size effect Location-specific Data analysis

Effect of scanning strategy on grain structure and crystallographic texture of Inconel 718 processed by selective laser melting

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Journal of Materials Science & Technology 2018年第10期34卷 1799-1804页

作者： H.y. wan Z.J. Zhou C.P. Li G.F. Chen G.P. Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China Materials & Manufacturing Qualification Group Corporate Technology Siemens Ltd. Beijing 100102 China

Two types of scanning strategies were adopted to study the effect of scanning strategy on grain structure and crystallographic texture of selective laser melted （SLM） Inconel 718. The results show that bidirec-tional scanning without and with a 90°-rotation for every layer produced the bimodal grain structure and the directional columnar grain structure, respectively. Controlling the heat flux direction between the successive layers via scanning strategy enabled the formation of such different grain structures. Fur-thermore, when the 90°-rotation was applied, the competitive grain growth mechanism became more pronounced and the strong cube texture developed.

关键词： Selective laser melting Additive manufacturing Scanning strategy Texture Grain structure

Historical and current climates affect the spatial distribution of herbivorous tree insects in China

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Journal of Forestry Research 2023年第5期34卷 1307-1321页

作者： Feixue Zhang Chunjing wang Jizhong wan State Key Laboratory of Plateau Ecology and Agriculture Qinghai UniversityXining 810016People’s Republic of China College of Agriculture and Animal Husbandry Qinghai UniversityXining 810016People’s Republic of China

Historical and current climate impacts reshape the evolutionary trajectory and ecological dynamics of entire vegetative communities,which can drive insect species *** the spatial distribution of insects can enhance forest management *** effects of historical and current climates in the spatial distribution of herbivorous tree insects in China were explored.A species distribution model simulated insect spatial distribution based on 596 species and the distribution probability and richness of these species were assessed in forest *** explanatory power of the historical climate was stronger than that of the current climate,particularly historical annual precipitation and annual mean temperatures,for the distribution of herbivorous *** both historical and current climatic conditions,herbivorous tree insects were and are mainly distributed in the North China Plain and the middle and lower reaches of the yangtze River Plain,namely in the Huang He Plain mixed forests,Changjiang Plain evergreen forests,and Sichuan Basin evergreen broadleaf *** yunnan-Guizhou Plateau and northeast China are regions with large impact differences between historical and current *** findings of this study provide valuable insights into herbivorous insect responses to sustained climate change and may contribute to long-term biodiversity conservation activities.

关键词： Bioclimatie variables Ecoregions Last glacial maximum Spatial distribution Species distribution model Herbivorous tree insects

Asymmetric flow effect in a horizontal natural ventilated tunnel with different aspect ratios under the influence of longitudinal fire locations

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Building Simulation 2021年第4期14卷 1311-1323页

作者： Longxing yu Huaxian wan Jie Ji State Key Laboratory of Fire Science University of Science and Technology of ChinaJinZhai Road 96HefeiAnhui230026China College of Environment and Resources Fuzhou UniversityXueyuan Road 2FuzhouFujian350116China

This paper has analyzed the asymmetric flow effect of fire-induced thermal flow in a horizontal tunnel under the natural ventilation condition by conducting large eddy simulations (LES). The key objective is to reveal and to have a better understanding of the asymmetric flow effect caused by the upstream and downstream tunnel length difference. The mechanism behind it can be explained based on the conservation of mass and dynamic force analysis on the smoke and fresh air. The strength of the asymmetric flow effect is characterized by the mass flow rate of the induced longitudinal flow (net mass flow rate of a cross-section). An empirical correlation to predict the induced longitudinal mass flow rate is proposed. Furthermore, the law of smoke and air flow distribution within a horizontal tunnel is established. The proportion of smoke (or air) flowing out (or coming in) through the opening increase (or decrease) linearly with the increasing distance between that opening to the fire location. The variation of the air flow with the longitudinal fire location in a tunnel is more sensitive than the smoke flow. Results have shown that as the fire approaches the tunnel exit from the middle of the tunnel, the smoke spilling out through this opening is reduced from 50% to 40%, while the fresh air incoming from this opening is increased from 50% to 100% and vice versa.

关键词： asymmetric flow effect fire location thermal flow smoke tunnel fire CFD