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国际医学放射学杂志 2021年第6期 736-737页

作者： y.Shi y.f.qi G.y.Lan Q.J.Wu B.Ma X.y.Zhang 杨瑞雪

在慢性乙型肝炎(CHB)或慢性丙型肝炎(CHC)中,测量肝脏的机械特性以分类肝脏的各种病理生理状态的价值尚未确定。目的评估多参数三维(3D)MR弹性成像作为

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Asymmetric reversible structural switching of a diene coordination polymer promoted by UV-visible light

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Science China Chemistry 2024年第2期67卷 536-541页

作者： yong Wang qiaoqiao Zhang yong-yong Cao qi Liu Brendan f.Abrahams Jian-Ping Lang College of Chemistry Chemical Engineering and MaterialsSoochow UniversitySuzhou215123China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China College of Biological Chemical Science and EngineeringJiaxing UniversityJiaxing314001China School of Chemistry University of MelbourneVictoria3010Australia

In natural and artificial systems,reversible reactions are commonly asymmetric with respect to the time scale and nature of the stimuli which drive the forward and backward *** applications for which switching behavior is required,it is desirable that the reversible reaction goes as close to symmetric as possible;however,such systems are ***,we report an example of ultraviolet(UV)-visible light-regulated asymmetric reversible structural switching involving a diene-based coordination polymer,CP1 and its monocyclobutane product,*** is possible to cycle at least ten times through a forward [2+2] photocycloaddition reaction and the reverse,photocleavage reaction.A single cycle can be completed within a few *** transformation is accompanied by fast and distinct fluorescence changes,arising from optimisation of the reaction *** functional theory calculations allow rationalisation of the asymmetric reversible transformation between CP1 and CP1a rather than between CP1 and its dicyclobutane product *** work provides a clear illustration of reversible structural switching which approaches symmetric behaviour with respect to reaction rate and *** insights gained from this work also assist in the design of fast,reversible switching materials.

关键词： asymmetrical reversible structural switching coordination polymer photocycloaddition UV-visible light-controlled fluorescence switching

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CT影像组学列线图术前预测胃癌淋巴结转移

国际医学放射学杂志 2020年第2期 250-250页

作者： y.Wang W.Liu y.yu J.J.Liu H.D.Xue y.f.qi 王天达 Department of Radiology Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical College

目的探讨CT影像组学术前预测胃癌淋巴结(LN)转移的价值。方法本回顾性研究包括247例手术证实的胃癌病人(训练组197例,测试组50例)。采用专用影像组

关键词：影像组学列线图淋巴结转移

Screening of low-friction two-dimensional materials from highthroughput calculations using lubricating figure of merit

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friction 2024年第8期12卷 1897-1908页

作者： Kewei TANG Weihong qi Guoliang RU Weimin LIU State Key Laboratory of Solidification Processing and Center of Advanced Lubrication and Seal Materials Northwestern Polytechnical UniversityXi’an 710072China Shandong Laboratory of yantai Advanced Materials and Green Manufacturing Yantai 265503China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Two-dimensional materials are excellent lubricants with inherent ***,superlubricity has been reported for only a few of these ***,other promising two-dimentional(2D)materials with different physical properties cannot be discovered or applied in production;thus,energy consumption can be greatly ***,we carry out high-throughput calculations for 1,4752D materials and screen for low-friction *** set a standard,we propose,for the first time,a geometry-independent lubricating figure of merit based on the conditions for stick-slip transition and our theory of Moiré*** the efficient calculation of this figure of merit,an innovative approach was developed based on an improved registry index *** calculations,340 materials were found to have a figure of merit lower than 10−***,a small set of 21 materials with a figure of merit lower than 10−4 were screened *** materials can provide diverse choices for various *** addition,the efficient computational approach demonstrated in this work can be used to study other stacking-dependent properties.

关键词： two-dimensional materials high-throughput calculation tribology low-friction materials Moirépatterns

Recursive filtering for Stochastic Systems With filter-and-forward Successive Relays

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1202-1212页

作者： Hailong Tan Bo Shen qi Li Hongjian Liu School of Mathematics-Physics and finance Anhui Polytechnic UniversityWuhu 241000China Anhui future Technology Research Institute Anhui Polytechnic UniversityWuhu 241000China College of Information Science and Technology Donghua UniversityShanghai 201620China Engineering Research Center of Digitalized Textile and fashion Technology Ministry of EducationShanghai 201620China School of Information Science and Engineering Hangzhou Normal UniversityHangzhou 311121China

In this paper,the recursive filtering problem is considered for stochastic systems over filter-and-forward successive relay(ffSR)*** ffSR is located between the sensor and the remote filter to forward the *** the successive relay,two cooperative relay nodes are adopted to forward the signals alternatively,thereby existing switching characteristics and inter-relay interferences(IRI).Since the filter-and-forward scheme is employed,the signal received by the relay is retransmitted after it passes through a linear *** objective of the paper is to concurrently design optimal recursive filters for ffSR and stochastic systems against switching characteristics and IRI of ***,a uniform measurement model is proposed by analyzing the transmission mechanism of ***,novel filter structures with switching parameters are constructed for both ffSR and stochastic *** the help of the inductive method,filtering error covariances are presented in the form of coupled difference ***,the desired filter gain matrices are further obtained by minimizing the trace of filtering error ***,the stability performance of the filtering algorithm is analyzed where the uniform bound is guaranteed on the filtering error ***,the effectiveness of the proposed filtering method over ffSR is verified by a three-order resistance-inductance-capacitance circuit system.

关键词： filtering successive stochastic

Chinese Clinical Named Entity Recognition Using Multi-feature fusion and Multi-Scale Local Context Enhancement

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Computers, Materials & Continua 2024年第8期80卷 2283-2299页

作者： Meijing Li Runqing Huang Xianxian qi College of Information Engineering Shanghai Maritime UniversityShanghai200306China

Chinese Clinical Named Entity Recognition(CNER)is a crucial step in extracting medical information and is of great significance in promoting medical ***,CNER poses challenges due to the specificity of clinical terminology,the complexity of Chinese text semantics,and the uncertainty of Chinese entity *** address these issues,we propose an improved CNER model,which is based on multi-feature fusion and multi-scale local context *** model simultaneously fuses multi-feature representations of pinyin,radical,Part of Speech(POS),word boundary with BERT deep contextual representations to enhance the semantic representation of text for more effective entity ***,to address the model’s limitation of focusing just on global features,we incorporate Convolutional Neural Networks(CNNs)with various kernel sizes to capture multi-scale local features of the text and enhance the model’s comprehension of the ***,we integrate the obtained global and local features,and employ multi-head attention mechanism(MHA)extraction to enhance the model’s focus on characters associated with medical entities,hence boosting the model’s *** obtained 92.74%,and 87.80%f1 scores on the two CNER benchmark datasets,CCKS2017 and CCKS2019,*** results demonstrate that our model outperforms the latest models in CNER,showcasing its outstanding overall *** can be seen that the CNER model proposed in this study has an important application value in constructing clinical medical knowledge graph and intelligent Q&A system.

关键词： CNER multi-feature fusion BiLSTM CNN MHA

Experimental investigation on weak shock wave mitigation characteristics of flexible polyurethane foam and polyurea

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Defence Technology（防务技术） 2024年第1期31卷 179-191页

作者： Shiyu Jia Cheng Wang Wenlong Xu Dong Ma fangfang qi State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Institute for Advanced Technology Shandong UniversityJinan250061China

In recent years,explosion shock wave has been considered as a signature injury of the current military *** strong shock wave is lethal to the human body,weak shock wave can cause many more lasting *** investigate the protection ability and characteristics of flexible materials and structures under weak shock wave loading,the blast wave produced by TNT explosive is loaded on the polyurethane foam with the density of 200.0 kg/m3(f-200)and 400.0 kg/m3(f-400),polyurea with the density of 1100.0 kg/m^(3)(P-1100)and structures composed of the two materials,which are intended for individual *** results indicate that the shock wave is attenuated to weak pressure disturbance after interacting with the flexible materials which are not *** shock wave protective capability of single-layer materials is dependent on their thickness,density and microscopic *** overpressure,maximum pressure rise rate and impulse of transmitted wave decrease exponentially with increase in sample *** the same thickness,f-400 provides better protective capability than f-200 while P-1100 shows the best protective capability among the three *** this study,as the materials are not destroyed,f-200 with a thickness more than10.0 mm,f-400 with a thickness more than 4.0 mm,and P-1100 with a thickness more than 1.0 mm can attenuate the overpressure amplitude more than 90.0%.further,multi-layer flexible composites are *** layer layouts of designed structures and layer thickness of the single-layer materials can affect the protective *** the research range,the structure in which polyurea is placed on the impact side shows the optimal shock wave protective performance,and the thicknesses of polyurea and polyurethane foam are 1.0 mm and 4.0 mm *** overpressure attenuation rate reached maximum value of 93.3%and impulse attenuation capacity of this structure are better than those of s

关键词： free-field explosion Weak shock wave mitigation Polyurea Polyurethane foam Multi-layered composites

One-dimensional molecular co-crystal alloys capable of full-color emission for low-loss optical waveguide and optical logic gate

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Aggregate 2024年第1期5卷 299-308页

作者： Zhenhong qi yu-Juan Ma Dongpeng yan Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryKey Laboratory of Radio-pharmaceuticals Ministry of EducationBeijing Normal UniversityBeijingChina

The luminescence color of molecule-based photoactive materials is the key to the applications in lighting and optical *** continuous regulation of emission color in molecular systems is highly desirable but still remains a challenge due to the individual emission band of purely organic ***,a novel alloy strategy based on molecular co-crystals is *** adjusting the molar ratio of pyrene(Py)and fluorathene(flu),three types of molecular co-crystal alloys(MCAs)assemblies are prepared involving Py-flu-OfN-x%,Py-flu-TfP-x%,Py-flu-TCNB-x%.Multiple energy level structure and förster resonance energy transfer(fRET)process endow materials with tunable full-spectra emission color in visible ***,these MCAs and co-crystals can be successfully applied to low optical loss waveguide and optical logic gate by virtue of all-color luminescence from blue across green to red,together with smooth surface of onedimensional microrods,which show promising applications as continuous light emitters for advance photonics applications.

关键词： full-color emission microrods molecular co-crystal optical waveguide organic alloys

A nonlinear wake model of a wind turbine considering the yaw wake steering

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Journal of Oceanology and Limnology 2024年第3期42卷 715-727页

作者： yunzhou LI Zhiteng GAO Shoutu LI Suiping qi Xiaoyu TANG College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Multi-function Towing Tank School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Energy and Power Engineering Lanzhou University of TechnologyLanzhou 730050China Institute of Oceanographic Instrumentation Qilu University of Technology(Shandong Academy of Sciences)Qingdao 266061China State Key Laboratory of Industrial Control Technology College of Control Science and EngineeringZhejiang UniversityHangzhou 310027China Laoshan Laboratory Qingdao 266237China

Duo to fluctuations in atmospheric turbulence and yaw control strategies,wind turbines are often in a yaw *** predict the far wake velocity field of wind turbines quickly and accurately,a wake velocity model was derived based on the method of momentum conservation considering the wake steering of the wind turbine under yaw *** consider the shear effect of the vertical incoming wind direction,a two-dimensional Gaussian distribution function was introduced to model the velocity loss at different axial positions in the far wake region based on the assumption of nonlinear wake *** work also developed a“prediction-correction”method to solve the wake velocity field,and the accuracy of the model results was verified in wake experiments on the Garrad Hassan wind ***,a 33-kW two-blade horizontal axis wind turbine was simulated using this method,and the results were compared with the classical wake model under the same parameters and the computational fluid dynamics(CfD)simulation *** results show that the nonlinear wake model well reflected the influence of incoming flow shear and yaw wake steering in the wake velocity ***,computation of the wake flow for the Horns Rev offshore wind farm with 80 wind turbines showed an error within 8%compared to the experimental *** established wake model is less computationally intensive than other methods,has a faster calculation speed,and can be used for engineering calculations of the wake velocity in the far wakefield of wind turbines.

关键词： far wake wake model wake steering wind shear wind farm

A High-Performance MoS_(2)-Based Visible-Near-Infrared Photodetector from Gateless Photogating Effect Induced by Nickel Nanoparticles

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Research 2024年第2期6卷 171-179页

作者： Ran Duan Weihong qi Panke Li Kewei Tang Guoliang Ru Weimin Liu State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi'an 710072China Shandong Laboratory of yantai Advanced Materials and Green Manufacturing Yantai 265503China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Recent advancements in two-dimensional materials have shown huge potential for optoelectronic *** is challenging to achieve highly effective and sensitive broadband photodetection based on MoS_(2)*** engineering,such as introducing vacancies,can narrow the bandgap and boost the separation of photogenerated carriers by defect states but leads to a slow response ***,we propose a nickel nanoparticle-induced gateless photogating effect with a unique energy band structure to enable the application of defect engineering and achieve high optoelectronic *** device based on Ni nanoparticle-decorated MoS_(2)with S vacancies exhibited high responsivities of 106.21 and 1.38 A W^(-1)and detectivities of 1.9×10^(12)and 8.9×10^(9)Jones under 532 and 980 nm illumination(visible to near infrared),respectively,with highly accelerated response *** strategy provides new insight into optimizing defect engineering to design high-performance optoelectronic devices capable of broadband photodetection.

关键词： defect Infrared illumination