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Coherence analysis of noise-like pulses generated by an erbium-doped fiber mode-locked laser

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Optoelectronics Letters 2024年第4期20卷 205-210页

作者： ZHANG Ziyi wang Chuncan LI Jing wang peng Key Laboratory of All Optical Network and Advanced Telecommunication Network Ministry of EducationInstitute of Lightwave TechnologyBeijing Jiaotong University Beijing 100044China

The noise-like pulses(NLPs)with tunable fraction of the pedestal height in the whole intensity autocorrelation(AC)trace are numerically demonstrated in the designed erbium-doped fiber(EDF)mode-locked laser,which contains the saturable absorber(SA)with nonlinear polarization rotation(NPR),sinusoidal-shaped or Gaussian-shaped filter,two segments of EDFs,and two pieces of single-mode fibers(SMFs)with normal dispersion and anomalous dispersion,*** pedestal ratio of the intensity AC trace can be tuned by changing the gain saturation energies of *** results show that when the net cavity dispersion is 1.06 ps^(2),the tuning range of the pedestal ratio for the NLPs can reach its maximum values,which are 0.51—0.89 and 0.58—0.88 for the sinusoidal-shaped and Gaussian-shaped filters,*** addition,an appropriate choice of filter bandwidth is also conducive to obtain a wide range of the tuning pedestal ratio for the intensity AC trace.

关键词： fiber tuning polarization

Influence of vapor pressure deficit on vegetation growth in China

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Journal of Arid Land 2024年第6期16卷 779-797页

作者： LI Chuanhua ZHANG Liang wang Hongjie peng Lixiao YIN peng MIAO Peidong College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China Hebei First Surveying and Mapping Institute Shijiazhuang 050000China

Vapor pressure deficit(VPD)plays a crucial role in determining plant physiological functions and exerts a substantial influence on vegetation,second only to carbon dioxide(CO_(2)).As a robust indicator of atmospheric water demand,VPD has implications for global water resources,and its significance extends to the structure and functioning of ***,the influence of VPD on vegetation growth under climate change remains unclear in *** study employed empirical equations to estimate the VPD in China from 2000 to 2020 based on meteorological reanalysis data of the Climatic Research Unit(CRU)Time-Series version 4.06(TS4.06)and European Centre for Medium-Range Weather Forecasts(ECMWF)Reanalysis 5(ERA-5).Vegetation growth status was characterized using three vegetation indices,namely gross primary productivity(GPP),leaf area index(LAI),and near-infrared reflectance of vegetation(NIRv).The spatiotemporal dynamics of VPD and vegetation indices were analyzed using the Theil-Sen median trend analysis and Mann-Kendall ***,the influence of VPD on vegetation growth and its relative contribution were assessed using a multiple linear regression *** results indicated an overall negative correlation between VPD and vegetation *** VPD intervals for the correlations between VPD and vegetation indices were identified:a significant positive correlation at VPD below 4.820 hPa,a significant negative correlation at VPD within 4.820–9.000 hPa,and a notable weakening of negative correlation at VPD above 9.000 *** exhibited a pronounced negative impact on vegetation growth,surpassing those of temperature,precipitation,and solar radiation in absolute ***_(2) contributed most positively to vegetation growth,with VPD offsetting approximately 30.00%of the positive effect of CO_(2).As the rise of VPD decelerated,its relative contribution to vegetation growth ***,the intensification of spatial variations in temperature an

关键词： vapor pressure deficit(VPD) near-infrared reflectance of vegetation(NIRv) leaf area index(LAI) gross primary productivity(GPP) Climatic Research Unit(CRU)Time-Series version 4.06(TS4.06) European Centre for Medium-Range Weather Forecasts(ECMWF)Reanalysis 5(ERA-5) climate change

A tectono-thermal perspective on the petroleum generation,accumulation and preservation in the southern Ordos Basin, North China

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Petroleum Science 2024年第3期21卷 1459-1473页

作者： peng Yang Zhan-Li Ren Jin-hua Fu Hong-Ping Bao Hui Xiao Zheng Shi Kun wang Yuan-Yuan Zhang Wen-Hui Liu Wen-Hou Li State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an710069ShanxiChina National Engineering Laboratory for Exploration and Development of Low-Permeability Oil and Gas Fields Exploration and Development Research Institute of PetroChina Changqing Oilfield CompanyXi'an710018ShaanxiChina Shaanxi Key Lab of Petroleum Accumulation Geology School of Earth Science and EngineeringXi'an Shiyou UniversityXian710065ShaanxiChina Wuxi Research Institute of Petroleum Geology Petroleum Exploration and Production Research InstituteSINOPECWuxi214126JiangsuChina

The southern Ordos Basin has excellent petroleum exploration ***,the tectono-thermal history and the controls on petroleum generation,accumulation and preservation conditions in southern basin are *** this study,we analyzed the present geothermal field,paleo-geothermal gradient,maturity of the hydrocarbon source rocks,uplift and cooling process and tectono-thermal evolution *** the study area,for the Ordovician,Permain and the Triassic strata,the present temperature is low(3070℃)in the southeastern area but high(80140℃)in the northwestern *** paleogeothermal gradient varied from 24℃/km to 30℃/km with a heat flow of 58—69 m W/m^(2)(i.e.,a medium-temperature basin).The paleo-temperatures are higher than the present temperatures and the maximum paleo-temperatures controlled the thermal maturity of the source *** vitrinite reflectance(Ro)values of the Triassic strata are>0.7%and the thermal maturity reached the middlemature oil generation *** Rovalues of the Permian-Ordovician strata are>1.8%and the thermal maturity reached the over-mature gas generation *** southern Ordos Basin has experienced the multiple tectonic events at the Late Ordovician Caledonian(452 Ma),Late Triassic(215 Ma),Late Jurassic(165160 Ma),End-Early Cretaceous(110100 Ma)and Cenozoic(since 40 Ma).A large-scale tectonothermal event occurred at the End-Early Cretaceous(110100 Ma),which was controlled by lithospheric extension,destruction and *** event led to the highest paleo-temperatures and thermal maturities and coeval with the peak period of petroleum generation and *** southern Ordos Basin has undergone rapid and large-scale uplift since the Late Cretaceous due to expansion of the northeastern margin of the Tibetan Plateau,uplift of the Qinling orogenic belt and thrust faulting in the Liupanshan tectonic *** southern Ordos Basin experienced tectonic overprinting that was strong in the south and weak in the *** str

关键词： Fission-track dating Vitrinitereflectance Geothermal field Tectono-thermal evolution Petroleum geology Ordos Basin

The crosstalk between enteric nervous system and immune system in intestinal development,homeostasis and diseases

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Science China(Life Sciences) 2024年第1期67卷 41-50页

作者： Xindi wang Chenbo Ding hua-Bing Li Shanghai Institute of Immunology State Key Laboratory of Oncogenes and Related GenesShanghai Jiao Tong University School of MedicineShanghai 200025China Shanghai Jiao Tong University School of Medicine-Yale Institute for Immune Metabolism Shanghai Jiao Tong University School of MedicineShanghai 200025China

The gut is the largest digestive and absorptive organ,which is essential for induction of mucosal and systemic immune responses,and maintenance of metabolic-immune *** intestinal components contain the epithelium,stromal cells,immune cells,and enteric nervous system(ENS),as well as the outers,such as gut microbiota,metabolites,and *** dyshomeostasis of intestinal microenvironment induces abnormal intestinal development and functions,even colon diseases including dysplasia,inflammation and *** recent studies have identified that ENS plays a crucial role in maintaining the immune homeostasis of gastrointestinal(GI)*** crosstalk between ENS and immune cells,mainly macrophages,T cells,and innate lymphoid cells(ILCs),has been found to exert important regulatory roles in intestinal tissue programming,homeostasis,function,and *** this review,we mainly summarize the critical roles of the interactions between ENS and immune cells in intestinal homeostasis during intestinal development and diseases progression,to provide theoretical bases and ideas for the exploration of immunotherapy for gastrointestinal diseases with the ENS as potential novel targets.

关键词： enteric nervous system macrophages T cells innate lymphoid cells neuro-immune interactions

Effects of main components on energy output characteristics of thermobaric explosive——A case study of typical formulations

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Defence Technology（防务技术） 2024年第8期38卷 205-216页

作者： Yunfei Zhao Yaning Li Zhiwei Han peng Bao Jingyan wang Boliang wang School of Chemistry&Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China School of Safety Science&Engineering Nanjing University of Science and TechnologyNanjing210094China

As a kind of high-efficiency explosive with compound destructive capability, the energy output law of thermobaric explosives has been receiving great attention. In order to investigate the effects of main components on the explosive characteristics of thermobaric explosives, various high explosives and oxidants were selected to formulate five different types of thermobaric explosive. Then they were tested in both open space and closed space respectively. Pressure measurement system, high-speed camera,infrared thermal imager and multispectral temperature measurement system were used for pressure,temperature and fireball recording. The effects of different components on the explosive characteristics of thermobaric explosive were analyzed. The results showed that in open space, the overpressure is dominated by the high explosives content in the formulation. The addition of the oxidants will decrease the explosion overpressure but will increase the duration and overall brightness of the fireball. While in closed space, the quasi-static pressure formed after the explosion is positively correlated with the temperature and gas production. In addition, it was found that the differences in shell constraints can also alter the afterburning reaction of thermobaric explosives, thus affecting their energy output characteristics. PVC shell constraint obviously increases the overpressure and makes the fireball burn more violently.

关键词： Thermobaric explosives Components Overpressure Fireball Afterburning reaction

Design,modeling and experimental investigation of a novel solar sail with high area-to-mass ratios for efficient solar sailing

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Chinese Journal of Aeronautics 2024年第10期37卷 234-248页

作者： Zhongjing REN Chengyang LI Ke WU Ziran wang Haipeng wang peng YAN Key Laboratory of High-efficiency and Clean Mechanical Manufacture(Ministry of Education) School of Mechanical EngineeringShandong UniversityJinan 250061China China Manned Space Agency Beijing 100071China

Solar sailing is a promising propellant-free approach to propelling spacecraft in ***,the propelling efficiency of conventional solar sail spacecraft is limited by their areato-mass *** paper proposes a novel design of micro solar sails with area-to-mass ratios above 100 m2/kg for next-generation chip-scale *** thin films developed by Microelectromechanical Systems(MEMS)technologies were patterned into grid microstructures,and theoretical analysis of a sail prototype was *** electro-thermal and thermo-mechanical models of the solar sail in geospace were established by taking effects of Joule heating,solar radiation,and thermal re-emission into consideration,enabling rapid prediction of its threedimensional(3-D)reconfiguration from the as-released two-dimensional(2-D)*** of the ChipSail’s acceleration arising from the sail’s morphing was also analytically *** and characterization of the sail prototype made of multiple Al/Ni50Ti50 bilayer beams were ***-situ SEM imaging of the sail prototype in vacuum chamber witnessed an active and continuous 3-D reconfiguration under Joule heating,and over 90deformation was detected by applying a DC voltage of 0.078 *** and experimental work on the solar sail with at least 10 times higher area-to-mass ratios than conventional ones will lay a solid foundation for efficient solar sailing.

关键词： Solar sails Solar sailing High area-to-mass ratios Solar radiation pressure ChipSail

Study on surface discharge of nonlinear conductive epoxy resin/SrTiO3 composites in 80–300 K temperature zone

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High Voltage 2024年第1期9卷 117-126页

作者： Yunqi Xing Bin wang Mingyang wang Jiakai Chi peng Jia Rongjin huang State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjinChina Key Laboratory of Electormagnetic Field and Electrical Apparatus Reliability of Hebei Province Hebei University of TechnologyTianjinChina Key Laboratory of Special Machine and High Voltage Apparatus(Ministry of Education) Shenyang University of TechnologyShenyangChina State Grid Tianjin High Voltage Company TianjinChina China Energy Engineering Group Tianjin Electric Power Design Institute Co. Ltd.TianjinChina CAS Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryBeijingChina

Bisphenol F epoxy resin(EP)is often used in terminal current lead insulation of superconducting equipment because of its good insulation performance,high mechanical strength,good toughness at cryogenic temperatures,and resistance to cold shock and heat ***,due to the wide temperature range of 80–300 K and the strong electric field,the EP-N_(2)interface is prone to surface flashover,resulting in terminal insulation *** improve the reliability of the current lead insulation,non-linear conductive EP/strontium titanate(SrTiO_(3))composites were prepared by modification with nano *** changes of dielectric,surface discharge,flashover,and trap distribution characteristics of composite materials were studied,and the mechanism of SrTiO_(3)on the surface flashover of composite materials was *** results show that the conductivity of the composite increases with the rise of SrTiO_(3)filling content,and the amplitude of improvement is greater under the strong electric field,showing a more significant *** composite has a lower trap energy level and a greater number of shallow traps compared to pure EP,which accelerates surface charge detrapping and reduces charge accumulation,effectively enhancing the discharge and surface flashover voltage of the composite.

关键词： composites composite insulation

Optimal investment based on relative performance and weighted utility

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 328-342页

作者： wang Lei DONG Ying-hui hua Chun-rong Department of Mathematics Suzhou University of Science and TechnologySuzhou 215009China Changshu Institute of Technology Changshu 215500China

This paper studies the optimal portfolio allocation of a fund manager when he bases decisions on both the absolute level of terminal relative performance and the change value of terminal relative performance comparison to a predefined reference point. We find the optimal investment strategy by maximizing a weighted average utility of a concave utility and an Sshaped utility via a concavification technique and the martingale method. Numerical results are carried out to show the impact of the extent to which the manager pays attention to the change of relative performance related to the reference point on the optimal terminal relative performance.

关键词： relative performance weighted utility S-shaped utility concavification

The Squeeze & Excitation Normalization Based nnU-Net for Segmenting Head & Neck Tumors

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Chinese Journal of Electronics 2024年第3期33卷 766-775页

作者： Juanying XIE Ying peng Mingzhao wang School of Computer Science Shaanxi Normal University

Head and neck cancer is one of the most common malignancies in the *** propose SE-nnU-Net by adapting SE(squeeze and excitation) normalization into nnU-Net,so as to segment head and neck tumors in PET/CT images by combining advantages of SE capturing features of interest regions and nnU-Net configuring itself for a specific *** basic module referred to convolution-ReLU-SE is designed for *** the encoder it is combined with residual structure while in the decoder without residual *** loss function combines Dice loss and Focal *** specific data preprocessing and augmentation techniques are developed,and specific network architecture is ***,the deep supervised mechanism is introduced to calculate the loss function using the last four layers of the decoder of *** SE-nnU-net is applied to HECKTOR 2020 and HECKTOR 2021 challenges,respectively,using different experimental *** experimental results show that SE-nnU-Net for HECKTOR 2020 obtained 0.745,0.821,and 0.725 in terms of Dice,Precision,and Recall,respectively,while the SE-nnU-Net for HECKTOR 2021 obtains 0.778 and 3.088 in terms of Dice and median HD95,*** SE-nnU-Net for segmenting head and neck tumors can provide auxiliary opinions for doctors diagnoses.

关键词： Image segmentation Head Data preprocessing Artificial neural networks Network architecture Data models Neck