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Chinese Science Bulletin 2005年第17期50卷 1940-1948页

作者： huang chunming1,2. zhang shaodong1,{2.,2.1. school of electronic information, wuhan universiy, wuhan 430079, china 2. Key Laboratory of Geospace Environment and Geodesy, Ministry of Education, wuhan University, wuhan 430079, china school of electronic {2. Wuhan University Wuhan 430079 China Key Laboratory of Geospace Environment and Geodesy Ministry of Education Wuhan University Wuhan 430079 China

By using a three-dimensional fully nonlinear numerical model in spherical coordinates and taking the linear steady solutions of the migrating diurnal and semidi-urnal tides in January from the Global-Scale Wave Model (GSWM) as the initial values, we simulate the linear and nonlinear propagations of the migrating diurnal and semidi-urnal tides in the atmosphere from the ground to the lower thermosphere. A comparison of our simulations with the results of GSWM is also presented. The simulation results show that affected by the nonlinearity, the migrating diurnal and semidiurnal tides propagating in the middle and upper atmosphere exhibit evident short-term variability. The nonlinear interactions between the migrating tides and the background atmosphere can obviously alter the background wind and temperature fields, which suggests that the nonlin-ear propagations of the migrating diurnal and semidiurnal tides impact significantly on the transient dynamical and thermal structures of the background middle and upper at-mosphere and the nonlinear effect is an important cause of the difference between the results of GSWM and observa-tions.

关键词：大气非线性传播数学模型可变性温度场

Game theory based finite-time formation control using artificial potentials for tethered space net robot

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Chinese Journal of Aeronautics 2024年第8期37卷 358-372页

作者： yifeng MA yizhai zhang Panfeng huang Ya LIU {2. zhang The Research Center for Intelligent Robotics School of AstronauticsNorthwestern Polytechnical UniversityXi’an 710072China school of electronic {2. and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The Tethered Space Net Robot(TSNR)is an innovative solution for active space debris capture and *** large envelope and simple capture method make it an attractive option for this ***,capturing maneuverable debris with the flexible and elastic underactuated net poses significant *** address this,a novel formation control method for the TSNR is proposed through the integration of differential game theory and robust adaptive control in this ***,the trajectory of the TSNR is obtained through the solution of a real-time feedback pursuit-evasion game with a dynamic target,where the primary condition is to ensure the stability of the ***,to minimize tracking errors and maintain a specific configuration,a robust adaptive formation control scheme with Artificial Potential Field(APF)based on a Finite-Time Convergent Extended State Observer(FTCESO)is *** proposed control method has a key advantage in suppressing complex oscillations by a new adaptive law,thus precisely maintaining the ***,numerical simulations are performed to demonstrate the effectiveness of the proposed scheme.

关键词： Game theory Formation control Artificial potential field Relative distance constraint Tethered space net robot(TSNR)

TEPG:a traffic engineering based power-aware greedy routing algorithm in backbone networks with bundled links

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Frontiers of Computer Science 2024年第1期18卷 243-245页

作者： Jinhong zhang Xingwei WANG Ruixia LI Bo yi Min huang Dongxing SHUI school of electronic and {2. Engineering West Anhui UniversityLu’an 237012China State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China school of Computer Science and Engineering Northeastern UniversityShenyang 110169China school of information Science and Engineering Northeastern UniversityShenyang 110819China

1 Introduction and main contributions Various power-aware solutions have been proposed to address the alarming energy waste and consequent serious environmental issues since Gupta and Singh initiated the seminal study on green networking problem in *** of the researches concentrated their efforts on power-aware networking under the non-bundled link scenarios by leveraging the dynamic power management based Low Power Idle(LPI)policy which was defined and standardized in the IEEE 802.3az ***,in modern backbone networks,pairs of routers are typically connected,for each traffic direction,by multiple physical links that form one logical bundled link,which is the link aggregation technique defined and standardized in IEEE 802.1.X.

关键词： power bundle backbone

TSCompiler: efficient compilation framework for dynamic-shape models

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Science china(information Sciences) 2024年第10期67卷 67-84页

作者： Xiang LUO Chen zhang Chenbo GENG Yanzhi yi Jiahui HU Renwei zhang Zhen zhang Gianpietro CONSOLARO fan YANG Tun LU Ning GU Li SHANG school of Computer Science Fudan University school of electronic {2. and Electrical Engineering Shanghai Jiao Tong University school of Computer Science and Technology Harbin Institute of Technology Huawei Technologies Co. Ltd. Huawei Paris Research Center school of Microelectronics Fudan University

Today's deep learning models face an increasing demand to handle dynamic shape tensors and computation whose shape information remains unknown at compile time and varies in a nearly infinite range at runtime. This shape dynamism brings tremendous challenges for existing compilation pipelines designed for static models which optimize tensor programs relying on exact shape values. This paper presents TSCompiler, an end-to-end compilation framework for dynamic shape models. TSCompiler first proposes a symbolic shape propagation algorithm to recover symbolic shape information at compile time to enable subsequent optimizations. TSCompiler then partitions the shape-annotated computation graph into multiple subgraphs and fine-tunes the backbone operators from the subgraph within a hardware-aligned search space to find a collection of high-performance schedules. TSCompiler can propagate the explored backbone schedule to other fusion groups within the same subgraph to generate a set of parameterized tensor programs for fused cases based on dependence analysis. At runtime, TSCompiler utilizes an occupancy-targeted cost model to select from pre-compiled tensor programs for varied tensor shapes. Extensive evaluations show that TSCompiler can achieve state-of-the-art speedups for dynamic shape models. For example, we can improve kernel efficiency by up to 3.97× on NVIDIA RTX3090, and 10.30× on NVIDIA A100 and achieve up to five orders of magnitude speedups on end-to-end latency.

关键词： machine learning tensor compilers dynamic shape operator fusion code generation auto-tuning

Mucosa color and size may indicate malignant transformation of chicken skin mucosa-positive colorectal neoplastic polyps

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 750-760页

作者： ying-Jie zhang Meng-Xia Yuan Wu Wen fan Li yi Jian Chuan-Ming zhang Ye Yang Feng-Lin Chen Department of Digestive Diseases Chengdu Second People’s HospitalChengdu 610000Sichuan ProvinceChina Graduate school Chengdu Medical CollegeChengdu 610000Sichuan ProvinceChina

BACKGROUND Lipid metabolism reprogramming is suspected to exist in pre-cancerous lesions,including colorectal *** colonoscopy frequently reveals chicken skin mucosa(CSM;white or yellow-white speckled mucosa)surrounding colo-rectal polyps,caused by macrophages engulfing and accumulating the lipids decomposed by colon cells or adjacent ***-positive colorectal polyps are associated with various diseases;however,their prognosis varies *** snare polypectomy is commonly used to resect lesions up to 10 to 15 mm in diameter without signs of submucosal invasion but is controversial for CSM-positive colorectal *** imaging is required to diagnose and treat CSM-positive colorectal *** This retrospective cohort study included 177 patients with CSM-positive colorectal polyps diagnosed using *** patient-related information was extracted from the Goldisc soft-clinic DICOM system or electronic medical record *** on the pathological results,patients were classified as non-neoplastic polyps(five juvenile polyps),neoplastic polyps,non-invasive high-grade neoplasia(NHGN),or submucosal invasive carcinoma(SM stage cancer).We analyzed and compared the clinical features,suspected risk factors for malignant transformation of neoplastic polyps,and early infiltration of sub-mucosal *** The diameters of NHGN and SM polyps were much smaller than those of neoplastic *** NHGN polyps had a deeper red mucosal *** logistic regression analyses,diameter and deeper red mucosal color were independent risk factors for malignant transformation of neoplastic *** 1 CSM was more common in high-grade intraepithelial neoplasia and SM;type 2.CSM was more common in neoplastic *** regression analyses revealed no significant differences in the malignant transformation of neoplastic polyps or early submucosal invasion of CSM-positive colorectal *** in the CSM mucosa surrounding neoplastic

关键词： Chicken skin mucosa Colorectal cancer Colorectal polyps Endoscopic resection Malignant transformation White light endoscopy

Highly Sensitive Ammonia Gas Sensors at Room Temperature Based on the Catalytic Mechanism of N,C Coordinated Ni Single-Atom Active Center

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Nano-Micro Letters 2024年第12期16卷 515-531页

作者： Wenjing Quan Jia Shi Min Zeng Wen Lv Xiyu Chen Chao fan Yongwei zhang Zhou Liu Xiaolu {2. Jianhua Yang Nantao Hu Tao Wang Zhi Yang National Key Laboratory of Advanced Micro and Nano Manufacture Technology Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Department of Micro/Nano electronics School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237People’s Republic of China

Significant challenges are posed by the limitations of gas sensing mechanisms for trace-level detection of ammonia(NH3).In this study,we propose to exploit single-atom catalytic activation and targeted adsorption properties to achieve highly sensitive and selective NH3 gas ***,Ni singleatom active sites based on N,C coordination(Ni-N-C)were interfacially confined on the surface of two-dimensional(2.)MXene nanosheets(Ni-N-C/Ti_(3)C_(2.Tx),and a fully flexible gas sensor(MNPE-Ni-N-C/Ti_(3)C_(2.Tx)was *** sensor demonstrates a remarkable response value to 5 ppm NH3(2..3%),excellent selectivity for NH3,and a low theoretical detection limit of 12.1.*** analysis by density functional calculation reveals that the Ni single-atom center with N,C coordination exhibits specific targeted adsorption properties for ***,its catalytic activation effect effectively reduces the Gibbs free energy of the sensing elemental reaction,while its electronic structure promotes the spill-over effect of reactive oxygen species at the gas-solid *** sensor has a dual-channel sensing mechanism of both chemical and electronic sensitization,which facilitates efficient electron transfer to the 2. MXene conductive network,resulting in the formation of the NH3 gas molecule sensing ***,the passivation of MXene edge defects by a conjugated hydrogen bond network enhances the long-term stability of MXene-based electrodes under high humidity *** work achieves highly sensitive room-temperature NH3 gas detection based on the catalytic mechanism of Ni single-atom active center with N,C coordination,which provides a novel gas sensing mechanism for room-temperature trace gas detection research.

关键词： Gas sensor Single atom Catalytic activation Targeted adsorption End-sealing passivation

Observations of gravity wave activity during stratospheric sudden warmings in the Northern Hemisphere

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Science china(Technological Sciences) 2015年第6期58卷 951-960页

作者： JIA Yue zhang shaodong yi {2. huang chunming huang KaiMing GAN Quan GONG Yun school of electronic {2. Wuhan University Key Laboratory of Geospace Environment and Geodesy Ministry of Education State Observatory for Atmospheric Remote Sensing State Key Laboratory of information Engineering in Surveying Mapping and Remote Sensing

Arctic stratospheric sudden warming(SSW) with polar vortex displacement and splitting occurred in 2.08 and 2.09, respectively. The temperature profiles derived from the Constellation Observing System for Meteorology, Ionosphere and Climate(COSMIC) along with NCEP/NCAR reanalysis are used to investigate the gravity wave(GW) variations during these SSW events. Some phenomena are characterized and possible mechanisms are discussed. The GW variations during both types of SSW events shared some similarities. During the warming events, enhanced zonal mean GW amplitudes are detected. The enhancements of GW amplitudes first appeared at higher altitudes and then progressed downward during the major warming events. The downward progressions correspond well with the height variations of the zonal wind reversal, and the enhancements seem to occur at the same time with the wind reversal. The spatial variations of GWs showed evident correlation to the polar vortex. Generally, GWs were enhanced at the edge of the polar vortex where the background wind was strong, whereas the areas with the largest GW amplitudes did not always correspond with those with the strongest background wind. The differences during the two types of SSW are also noticeable. In the 2.08 major event, the magnitudes of the zonal mean GW enhancements during the downward progression were relatively stable, whereas in the 2.09 major event, a clear reduction was detected as the GW enhancement was progressing downward. Also, the recovery time of the polar vortex was longer in 2.09. These differences indicate that different types of SSWs may have different impacts on the GW.

关键词： stratospheric sudden warming gravity wave COSMIC

Self-assembled monolayers(SAMs)in inverted perovskite solar cells and their tandem photovoltaics application

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Interdisciplinary Materials 2024年第2期3卷 203-244页

作者： Zijun yi Xin Li Yuchen Xiong Guibin Shen Wenguang zhang yihuai huang Qinghui Jiang Xin Ren Ng Yubo Luo Jianghui Zheng Wei Lin Leong {2. Fu Tongle Bu Junyou Yang State Key Laboratory of Material Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhanChina china‐Eu Institute for Clean and Renewable Energy Huazhong University of Science and TechnologyWuhanChina school of Electrical and electronic Engineering Nanyang Technological UniversitySingaporeSingapore Department of Chemistry National University of SingaporeSingaporeSingapore school of Physics The University of SydneySydneyNew South WalesAustralia Laboratory for Thin Films and Photovoltaics Empa‐Swiss Federal Laboratories for Materials Science and TechnologyDübendorfSwitzerland State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhanChina

Self-assembled monolayers(SAMs)employed in inverted perovskite solar cells(PSCs)have achieved groundbreaking progress in device efficiency and stability for both single-junction and tandem configurations,owing to their distinctive and versatile ability to manipulate chemical and physical interface *** this regard,we present a comprehensive review of recent research advancements concerning SAMs in inverted perovskite singlejunction and tandem solar cells,where the prevailing challenges and future development prospects in the applications of SAMs are *** thoroughly examine the mechanistic roles of diverse SAMs in energy-level regulation,interface modification,defect passivation,and charge *** is achieved by understanding how interfacial molecular interactions can be finely tuned to mitigate charge recombination losses in inverted *** this comprehensive review,we aim to provide valuable insights and references for further investigation and utilization of SAMs in inverted perovskite single‐junction and tandem solar cells.

关键词： inverted perovskite solar cells power conversion efficiency self-assembled monolayers tandem

Radiosonde observations of high-latitude planetary waves in the lower atmosphere

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Science china Earth Sciences 2010年第6期53卷 919-932页

作者： WANG Rui1,2.3, zhang shaodong1,2.3 & yi {2.,2.3 1 school of electronic information, wuhan University, wuhan 430079, china 2.Key Laboratory of Geospace Environment and Geodesy, Ministry of Education, wuhan 430079, china 3 State Observatory for Atmospheric Remote Sensing, wuhan 430079, china 1. school of electronic {2. Wuhan University Wuhan 430079 China2. Key Laboratory of Geospace Environment and Geodesy Ministry of Education Wuhan 430079 China3. State Observatory for Atmospheric Remote Sensing Wuhan 430079 China

The characteristics of high-latitude planetary waves (PWs) in the troposphere and lower stratosphere (TLS) are studied by using the data from radiosonde observations during 1998 to 2.06 at three Alaskan stations in USA (Nome, 64.50°N, 165.43°W; McGrath, 62.97°N, 155.62.W; Fairbanks, 64.82.N, 147.87°W). It is found that strong PWs exist in two regions. One is around tropopause, and the other is in the polar night jet (PNJ) in winter. The PW activities are rather intermittent, and their lifetimes are no longer than two months. Among three perturbation components in zonal and meridional winds and temperature, the temperature disturbance amplitude is the smallest, and the amplitude for the meridional wind component the largest. Around the tropopause, quasi 5-, 10-, and 16-day PW activities can be observed simultaneously. Among these PW components, the quasi 5-day and 10-day PW are the weakest and strongest, respectively. Moreover, PWs around the tropopause are complex and no obvious season variability can be observed. However, in the PNJ, the higher region, only obvious quasi 10-day and 16-day PWs remain, with smaller amplitudes than those around the tropopause. And significant PWs in the PNJ occur only in winter. By calculating the refractive index for PWs, it is found that there is a persistent reflection layer around 11 km, which is thick in summer and becomes thin or even disappears in winter, revealing that PWs in the stratosphere can only occur in winter. PWs in the 2.03/2.04 winter at the three stations are analyzed in detail. It is found that for the focused observation duration, the quasi 10-day and quasi 16-day waves exist mainly in the troposphere and stratosphere, respectively. The quasi 10-day wave is a standing wave in the vertical direction, with vertical wavelength about 12.km in the temperature component and larger than 2. km in the meridional component. Moreover, the tropospheric quasi 10-day wave propagates westward with the zonal numbers between 2.an

关键词： planetary waves troposphere and lower stratosphere radiosonde

Climatology of global gravity wave activity and dissipation revealed by SABER/TIMED temperature observations

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Science china(Technological Sciences) 2014年第5期57卷 998-1009页

作者： SHUAI Jing zhang shaodong {2. chunming yi fan {2. KaiMing GAN Quan GONG Yun electronic information {2. Wuhan University Key Laboratory of Geospace Environment and Geodesy Ministry of Education State Observatory for Atmospheric Remote Sensing

Gravity wave activity and dissipation in the height range from the low stratosphere to the low thermosphere(2.–115 km)covering latitudes between 50°S and 50°N are statistically studied by using 9-year(January 2.,2.02.December 31,2.1.)SABER/TIMED temperature *** propose a method to extract realistic gravity wave fluctuations from the temperature profiles and treat square temperature fluctuations as GW ***,the gravity wave activity generally increases with *** the equator(0°–10°),the gravity wave activity shows a quasi-biennial variation in the stratosphere(below 40 km)while from 2.°to 30°,it exhibits an annual variation below 40 km;in low latitudes(0°–30°)between the upper stratosphere and the low thermosphere(40–115 km),the gravity wave activity shows a semi-annual *** middle latitudes(40°–50°),the gravity wave activity has a clear annual variation below 85 *** addition,we observe a four-monthly variation with peaks occurring usually in April,August,December in the northern hemisphere and in February,June,October in the southern hemisphere,respectively,above 85 km in middle latitudes,which has been seldom reported in gravity wave *** order to study the dissipation of gravity wave propagation,we calculate the gravity wave dissipation ratio,which is defined as the ratio of the gravity wave growth scale height to the atmosphere density scale *** height variation of the dissipation ratio indicates that strong gravity wave dissipation mainly concentrates in the three height regions:the stratosphere(30–60 km),the mesopause(around 85 km)and the low thermosphere(above 100 km).Besides,gravity wave energy enhancement can be also observed in the background atmosphere.

关键词： gravity wave dissipation climatology middle and high atmosphere TIMED/SABER