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Atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering correction

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Nuclear Science and Techniques 2024年第3期35卷 40-52页

作者： Ding-Han Zhu Xiong zhang Xiao-Qiang Li Peng Li Yan-bin Wang Shuang zhang State Key Laboratory of NBC Protection for Civilian Beijing 102205China

In high-altitude nuclear detonations,the proportion of pulsed X-ray energy can exceed 70%,making it a specific monitoring signal for such *** pulsed X-rays can be captured using a satellite-borne X-ray detector following atmospheric *** quantitatively analyze the effects of different satellite detection altitudes,burst heights,and transmission angles on the physical processes of X-ray transport and energy fluence,we developed an atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering *** proposed method is an improvement over the traditional analytical method that only computes direct-transmission *** traditional analytical method exhibits a maximum relative error of 67.79% compared with the Monte Carlo *** improved method reduces this error to within 10% under the same conditions,even reaching 1% in certain ***,its computation time is 48,000 times faster than that of the Monte Carlo *** results have important theoretical significance and engineering application value for designing satellite-borne nuclear detonation pulsed X-ray detectors,inverting nuclear detonation source terms,and assessing ionospheric effects.

关键词： High-altitude nuclear detonation Atmospheric transmission Pulsed X-rays Scattering correction Analytical method Monte Carlo method

从利用资本主义到巩固社会主义的监督体制创新——列宁《布尔什维克能保持国家政权吗?》监督思想管窥及现实启示

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中国地质大学学报（社会科学版） 2021年第1期21卷 10-18页

作者：张文彬同济大学马克思主义学院上海200092

《布尔什维克能保持国家政权吗?》写于十月革命前夕,列宁在文章中既驳斥了对无产阶级单独夺取并保持政权的质疑,也论证了无产阶级政权在化解危机、管理国家方面的独特优势。列宁指出,由工农群众承担监督工作,对资产阶级进行监督而非消灭... 详细信息

《布尔什维克能保持国家政权吗?》写于十月革命前夕,列宁在文章中既驳斥了对无产阶级单独夺取并保持政权的质疑,也论证了无产阶级政权在化解危机、管理国家方面的独特优势。列宁指出,由工农群众承担监督工作,对资产阶级进行监督而非消灭,不劳动者不得食,对社会生产和分配实行精确计算等措施是实现向社会主义过渡的关键步骤。早期监督思想进一步深化了列宁的社会主义革命理论,开启了防止官僚主义滋生的制度化建设之路,拓展了人民群众的立体化监督方式,解决了革命胜利后如何建设社会主义的现实难题。列宁早期监督思想对新时代中国特色社会主义权力监督体系建设具有重要的现实启示:有助于推进社会主义建设的顶层设计与制度创新,有助于克服官僚主义和个人专权,有助于落实人民民主的思想,凸显人民群众的主体地位。

关键词：列宁监督无产阶级民主

中国货币政策的区域经济稳定效应分析——基于2000-2008年省份月度数据的实证研究

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财经研究 2010年第10期36卷 15-25页

作者：张文彬北京大学光华管理学院北京100871

文章基于TVP-GARCH模型构建货币政策反应函数,利用时变参数模型构建包含货币政策变量的省份宏观经济波动模型,发现货币政策对各省份经济的稳定性作用并不明显,可预期的货币政策的省份稳定效应高于不可预期的货币政策,而经济冲击和货币... 详细信息

文章基于TVP-GARCH模型构建货币政策反应函数,利用时变参数模型构建包含货币政策变量的省份宏观经济波动模型,发现货币政策对各省份经济的稳定性作用并不明显,可预期的货币政策的省份稳定效应高于不可预期的货币政策,而经济冲击和货币政策制定层面引发的货币增长的不确定性,加大了省份经济波动;货币政策的经济稳定能力存在明显的省份差异,和经济周期同步性以及货币、信用和汇率三个传导渠道的省份特征密切相关。

关键词：货币政策区域效应经济稳定时变参数模型

The Effect of Blending Ratio on the Structure and Properties of the PPR/PS In situ Fiber Reinforced System Prepared by Multi-Flow Vibration Injection Molding

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Chinese Journal of Polymer Science 2024年第6期42卷 851-863页

作者： Yan-Jiang Li Meng-Long Hu Jun-wen zhang Qiang Fu Jie zhang College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China

To enhance the mechanical properties of polypropylene random copolymer(PPR),polystyrene(PS)with four different contents were added to the PPR matrix through melt ***,using the Multi-Flow Vibration Injection Molding(MFVIM)technology,PPR/PS in situ microfiber composites(MFC)with different blending ratios were *** results indicated that blending ratio had a great impact on the phase morphology and crystal structure of MFVIM samples,which was different from those of conventional injection molding(CIM)*** ultrafine fibers could be formed under the shear field and could absorb the PPR molecular chains to form hybrid shish-kebab ***,the PPR matrix could also form shish-kebab structures under the effect of strong *** the PS content reached 20%,under the combined action of PS in situ microfibers and highly oriented crystal structure,the tensile strength and Young’s modulus of the sample were obviously improved and the impact strength remained at a relatively high *** a strong and tough balanced PPR based material was *** results provide valuable insights for expanding the industrial and daily-life applications of PPR and show promising development prospects.

关键词： PPR MFVIM In situ microfibers Shearfield Hybrid shish-kebab structures

Performance improvements in complementary metal oxide semiconductor devices and circuits based on fin field-effect transistors using 3-nm ferroelectric Hf_(0.5)Zr_(0.5)O_(2)

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Rare Metals 2024年第7期43卷 3242-3249页

作者： Zhao-Hao zhang Yan-Na Luo Gao-Bo Xu Jia-Xin Yao Zhen-Hua Wu Hong-bin Zhao Qing-Zhu zhang Hua-Xiang Yin Jun Luo wen-Wu Wang Hai-Ling Tu Integrated Circuit Advanced R&D Center Institute of Microelectronics of Chinese Academy of SciencesBeijing 100029China School of Integrated Circuits University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Advanced Materials for Smart Sensing General Research Institute for Nonferrous MetalsBeijing 100088China

In this work,a conventional HfO_(2) gate dielectric layer is replaced with a 3-nm ferroelectric(Fe) HZO layer in the gate stacks of advanced fin field-effect transistors(FinFETs).Fe-induced characteristics,e.g.,negative drain induced barrier lowering(N-DIBL) and negative differential resistance(NDR),are clearly observed for both p-and n-type HZO-based *** characteristics are attributed to the enhanced ferroelectricity of the 3-nm hafnium zirconium oxide(HZO) film,caused by Al doping from the TiAlC capping *** mechanism is verified for capacitors with structures similar to the *** to the enhanced ferroelectricity and N-DIBL phenomenon,the drain current(I_(DS))of the HZO-FinFETs is greater than that of HfO_(2)-FinFETs and obtained at a lower operating ***,circuits based on HZO-FinFET achieve higher performance than those based on HfO_(2)-FinFET at a low voltage drain(V_(DD)),which indicates the application feasibility of the HZO-FinFETs in the ultralow power integrated circuits.

关键词： FinFET Ferroelectric Hafnium zirconium oxide Subthreshold swing Low power

Energy-efficient low-latency virtual cluster synchronization algorithm based on SMAC protocol in wireless sensor networks

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Journal of Harbin Institute of Technology(New Series) 2012年第5期19卷 54-60页

作者：何晨光沙学军张文彬吴玮 Communication Research Center Harbin Institute of Technology

The MAC protocol design for wireless sensor networks has been researched and developed for decades. SMAC protocol is a famous energy-efficient MAC protocol. Based on SMAC protocol, we find that the boundary nodes in the cluster-shaped synchronization structure bring energy consumption seriously, and provide a virtual cluster aggregation (VCA) algorithm. Because the bounder node follows multiple schedules in one cycle, it may deplete earlier and cause segmentation in wireless sensor networks. The algorithm reduces energy consumption of boundary nodes and extends the lifetime of entire sensor network by merging different virtual clusters, but increases the data transmission delay. Because the sensor nodes have the fixed duty cycle, the larger the coverage area of network is, the greater the data transmission delay increases. We propose the dynamic duty cycle (DDC) algorithm to solve this effect. When the network load and data transmission delay increase, the DDC algorithm exponentially changes the duty cycle of the node to reduce latency. The simulation results show that the performance of SMAC with the VCA and DDC algorithm obtains improvement significantly.

关键词： wireless sensor network virtual cluster aggregation duty cycle energy-efficient delay

Feedback of Efficient Shock Acceleration on Magnetic-field Structure Inside Young Type Ia Supernova Remnants

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Research in Astronomy and Astrophysics 2024年第6期24卷 234-244页

作者： Jun-Yu Shen Bi-wen Bao Li zhang Department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan ProvinceYunnan UniversityKunming 650091China Key Laboratory of Statistical Modeling and Data Analysis of Yunnan Province Yunnan UniversityKunming 650091China

Using an effective adiabatic index γ_(eff) to mimic the feedback of efficient shock acceleration,we simulate the temporal evolution of a young type Ia supernova remnant (SNR) with two different background magnetic field(BMF) topologies:a uniform and a turbulent *** density distribution and magnetic-field characteristics of our benchmark SNR are studied with two-dimensional cylindrical magnetohydrodynamic *** γ_(eff)is considered,we find that:(1) the two-shock structure shrinks and the downstream magnetic-field orientation is dominated by the Rayleigh–Taylor instability structures;(2) there exists more quasi-radial magnetic fields inside the shocked region;and (3) inside the intershock region,both the quasi-radial magnetic energy density and the total magnetic energy density are enhanced:in the radial direction,with γ_(eff)=1.1,they are amplified about 10–26 times more than those with γ_(eff)=5/*** in the angular direction,the total magnetic energy densities could be amplified about 350 times more than those with γ_(eff)=5/3,and there are more grid cells within the intershock region where the magnetic energy density is amplified by a factor greater than 100.

关键词： methods:numerical ISM:magnetic fields ISM:supernova remnants magnetohydrodynamics(MHD)

Ferromagnetism and insulating behavior with a logarithmic temperature dependence of resistivity in Pb_(10-x)Cux(PO_(4))_(6)O

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 106-111页

作者： Yuhang zhang Cong Liu Xiyu Zhu Hai-Hu wen Center for Superconducting Physics and Materials National Laboratory of Solid State Microstructures and Department of PhysicsNational Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

Recent claim of discovering above-room-temperature superconductivity(Tc≈400 K)at ambient pressure in copper doped apatite Pb10(PO_(4))_(6)O has stimulated world-wide enthusiasm and impulse of motion.A lot of follow-up works have been carried out with controversial *** check whether superconductivity is really present or absent in the material,we need samples which should have a rather pure phase of Pb_(10-x)Cux(PO_(4))_(6)*** we report the characterization results from the Pb_(10-x)Cux(PO_(4))_(6)O with a fraction of about 97 wt.%inferred from the fitting to the X-ray diffraction pattern,if assuming Cu2S as the only *** resistivity measurements show that it is a semiconductor characterized roughly by a ln(1/T)temperature dependence in wide temperature region without trace of *** measurements show that it has a general ferromagnetic signal with a weak superparamagnetic *** grains of the sample show clear interactions with a Nb Fe B *** detected Cu concentration is much lower than the expected nominal *** results show the absence of metallicity and superconductivity in Pb_(10-x)Cux(PO_(4))_(6)O at ambient pressure,and suggest the presence of strong correlation effect.

关键词： superconductivity Pb10(PO4)6O ferromagnetic correlation effect

ASYMPTOTIC THEORY FOR THE CIRCUIT ENVELOPE ANALYSIS

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Journal of Computational Mathematics 2024年第4期42卷 955-978页

作者： Chunxiong Zheng Xianwei wen Jinyu zhang Zhenya Zhou College of Mathematics and Systems Science Xinjiang UniversityUrumqi 830046China Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China Empyrean Software Empyrean Technology Co.Ltd.Beijing 100102China

Asymptotic theory for the circuit envelope analysis is developed in this paper.A typical feature of circuit envelope analysis is the existence of two significantly distinct timescales:one is the fast timescale of carrier wave,and the other is the slow timescale of modulation *** first perform pro forma asymptotic analysis for both the driven and autonomous *** resorting to the Floquet theory of periodic operators,we make a rigorous justification for first-order asymptotic *** turns out that these asymptotic results are valid at least on the slow *** speed up the computation of asymptotic approximations,we propose a periodization technique,which renders the possibility of utilizing the NUFFT *** experiments are presented,and the results validate the theoretical findings.

关键词： Asymptotic analysis Circuit envelope analysis Floquet theory Singularly perturbed problem