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不同格网尺度下生态系统服务价值空间分异及影响因素分析——以秦岭西安段为例

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水土保持研究 2025年第1期32卷 389-399页

作者：马超群弋志强员学锋张硕蒙张莎莎长安大学土地工程学院陕西省土地整治重点实验室

[目的]探究生态系统服务价值空间分异的尺度效应，为秦岭地区的生态保护和经济发展决策提供参考。[方法]运用改进当量因子法，计算了2020年秦岭西安段5 km, 3 km, 2 km, 1 km和0.5 km共5个格网尺度水平上的生态系统服务价值；采用空间... 详细信息

[目的]探究生态系统服务价值空间分异的尺度效应，为秦岭地区的生态保护和经济发展决策提供参考。[方法]运用改进当量因子法，计算了2020年秦岭西安段5 km, 3 km, 2 km, 1 km和0.5 km共5个格网尺度水平上的生态系统服务价值；采用空间自相关分析和冷热点分析归纳了不同尺度下地均ESV空间分异特征；并利用地理探测器对各尺度下的影响因素作用强度进行定量分析。[结果](1)地均ESV总体上呈北低南高的分布格局，具有小分散、大集聚的空间分布特征，并随尺度降低，其局部越丰富，但整体性降低；(2) 2 km尺度适合进行宏观分析和做整体性布局规划，1 km尺度适合进行水域变化对区域ESV影响的研究；(3)格网尺度越小，各影响因素内部差异增加，其整体性特征减少，局部特征差异凸显，空间分异性增强；(4)人类活动带来的土地利用方式转变显著影响区域生态系统服务价值，多因素耦合作用显著影响区域地均ESV空间分异，随尺度降低，其影响减弱。[结论]秦岭西安段的生态保护要重点关注区域土地利用性质的转变，可继续加强退耕还林政策，管控建设用地的规模，在兼顾生态保护的基础上，制定经济发展的布局规划。

关键词：生态系统服务价值空间分异地理探测器多尺度秦岭西安段

Montel-Type Theorems in Several Complex Variables with Continuously Moving Targets

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Chinese Annals of Mathematics,Series B 2010年第3期31卷 373-384页

作者： Zhenhan TU shasha zhang Department of Mathematics and Statistics Wuhan University Wuhan 430072 China

The authors introduce a new idea related to Montel-type theorems in higher dimension and prove some Montel-type criteria for normal families of holomorphic mappings and normal holomorphic mappings of several complex variables into PN(C) for continuously moving hyperplanes in pointwise general position. The main results are also true for continuously moving hypersurfaces in pointwise general position. Examples are given to show the sharpness of the results.

关键词： Holomorphic mappings Normal families Picard-type theorems Valuedistribution theory

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The rising star in photovoltaics-perovskite solar cells: The past, present and future

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Science China(Technological Sciences) 2016年第7期59卷 989-1006页

作者： FANG Rui zhang WenJun zhang shasha CHEN Wei Michael Gratzel Centre for Mesoscopic Solar Cells Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhan 430074China

Perovskite solar cell(PVSC), after its invention since 2009, has attracted tremendous attention from both academia and industry, because of its low cost, ease of manufacturing features and the sky-rocketing efficiencies being achieved within such a short period of time. Currently, the new efficiency record has reached 21.0%, comparable to that of the commercialized PV technologies developed for decades, such as multi-crystalline Si, CIGS and Cd Te thin film solar cells. It is very possible that PVSCs would one day step over the threshold of marketization, share or even overturn the current PV market dominated by crystalline-Si solar cells. However, there are still several obstacles to be overcome on the road towards PVSC industrialization. This paper has reviewed the brief developing history and the current research status of PVSCs, and explained: Why PVSCs are so important in the next-generation solar cells, why organometal halide perovskites work so well as light absorbers, and what the inherent differences are among different cell configurations. The prospects on how to realize scale-up industrialization of PVSCs have also been given in the sequence of efficiency, stability, cost, toxicity, and short-term objectives. Resolutions to the remaining challenges according to their orders of technical difficulty and importance have also been discussed.

关键词： organometal halides perovskite solar cells cell configurations efi ciency records stability industrialization prospects

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On the bit-based division property of S-boxes

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Science China(Information Sciences) 2022年第4期65卷 261-263页

作者： Zejun XIANG Xiangyong ZENG shasha zhang Faculty of Mathematics and Statistics Hubei Key Laboratory of Applied MathematicsHubei University

Dear editor,The S-box, which is one of the most popular cipher components, has been extensively applied in modern symmetrickey primitives. Moreover, it is often the case that S-boxes are the only nonlinear components ... 详细信息

关键词： division property Sbox ANF divisional optimal divisional suboptimal

Microstructural evolution and mechanical properties of Nb-Si-Cr ternary alloys with a tri-phase Nb/Nb5Si3/Cr2Nb microstructure fabricated by spark plasma sintering

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Progress in Natural Science:Materials International 2018年第5期28卷 626-634页

作者： shasha zhang Wei Liu Jiangbo Sha School of Materials Science and Engineering Beihang University Welding and Plastic Forming Division Beijing Institute of Aeronautical Materials

In this work,pure Nb,Nb;Si;and Laves Cr;Nb compound powders were used as raw materials to prepare Nb-SiCr ternary alloys by spark plasma sintering（SPS）.A comprehensive estimation of the microstructure and properties,including room temperature fracture toughness,high temperature strength and oxidation resistance,of the Nb-Si-Cr ternary alloys as a function of the Nb/Nb;Si;/Cr;Nb phase volume fraction combinations was *** results showed that Nb-Si-Cr ternary samples with the relative density larger than 98.42% were obtained by SPS processing,and the samples all consisted of Nb,Nb;Si;and Cr;Nb phases that were distributed *** fracture toughness K;of the Nb/Nb;Si;/Cr;Nb microstructure,which was dominated by the Nb phase,naturally increased with the Nb *** expected,the room-temperature Vickers hardness and the high-temperature strength of the bulk alloys increased monotonically with the increasing of the stiffening Nb;Si;***,the binary Cr;Nb phase played a positive role in the high temperature strength and oxidation ***,the fracture modes of the typical Nb/Nb;Si;/Cr;Nb microstructures under bending and compression conditions at room and high temperatures as well as the oxidation mechanism are described and discussed.

关键词： Nb-Si Alloy Spark Plasma Sintering(SPS) Phase Fraction Fracture Toughness High-Temperature Strength

A Review of Self-healing Metals: Fundamentals, Design Principles and Performance

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Acta Metallurgica Sinica(English Letters) 2020年第9期33卷 1167-1179页

作者： shasha zhang Niels van Dijk Sybrand van der Zwaag College of Materials and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key Laboratory of Materials Preparation and Protection for Harsh Environment(Nanjing University of Aeronautics and Astronautics) Ministry of Industry and Information TechnologyNanjing 211106China Fundamental Aspects of Materials and Energy Group Faculty of Applied SciencesDelft University of TechnologyMekelweg 152629 JB DelftThe Netherlands Novel Aerospace Materials Group Faculty of Aerospace EngineeringDelft University of TechnologyKluyverweg 12629 HS DelftThe Netherlands School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

Self-healing metals possess the capability to autonomously repair structural damage during service. While self-healing concepts remain challenging to be realized in metals and metallic systems due to the small atomic volume of the mobile atoms, the slow diffusion unless at high temperatures and the strong isotropic metallic bonds, the scientific interest has increased sharply and promising progress is obtained. This article provides a comprehensive and updated review on the developments and limitations associated with the various modes of potentially healable damage induced in metals and alloys, i.e., stressinduced damage, irradiation-induced damage in bulk materials and contact damage in corrosion protective coatings. The spontaneous intrinsic healing mechanisms not requiring external assistance other than the material operating at the right temperature and an assisted healing mechanism with external intervention are reviewed. Promising strategies to achieve self-healing in metals are identified. Finally, we give some prospects for future research directions in self-healing metals.

关键词： Metal Self-healing Creep behavior Fatigue damage Irradiation Coating

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Cube attacks on round-reduced MORUS and GimLi

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Science China(Information Sciences) 2022年第1期65卷 265-267页

作者： Siwei CHEN Zejun XIANG Xiangyong ZENG shasha zhang Faculty of Mathematics and Statistics Hubei Key Laboratory of Applied MathematicsHubei University

Dear editor,Cube attack is a chosen plaintext/initial value(IV) keyrecovery attack, which was proposed by Dinur and Shamir at EUROCRYPT 2009 [1]. As an important cryptanalysis technique, it is widely used in symmetric ciphers. The main ideal of cube attack is to look for cubes to acquire several linear polynomials(superpolys) with respect to secret variables. The secret variables can be recovered by solving these linear equations. However, thus far, no general method has been established to search for cubes.

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Design and indoor simulated experiment of pneumatic rice seed metering device

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International Journal of Agricultural and Biological Engineering 2015年第4期8卷 10-18页

作者： zhang Guozhong Zang Ying Luo Xiwen Wang Zaiman zhang Qiang zhang shasha College of Engineering Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Key Technology on Agricultural Machine and Equipment Ministry of EducationSouth China Agricultural UniversityGuangzhou 510642China Modern Agricultural Equipment Engineering Technology Research Center Wuhan 430070China

In order to meet the agronomy demand for hybrid rice direct seeding,a novel precise pneumatic rice seed metering device was designed with groups of sucking holes plate,by which 3-4 seeds could be synchronously sucked and synchronously dropped into the paddy *** plate was divided into five sections:seed sucking,seed clearing,seed carrying,seed dropping,and blank *** seeds were sucked in sucking section by the vacuum,carried and rotated to the dropping section with the plate,blown away in dropping section by the positive pressure air,and thrown into the dropping *** influences of the hole diameter,vacuum degree,and clear-up equipment on precision of metering device were *** were conducted to investigate the seeding precision and simulate the field emergence rates on the indoor seeding *** subjects were pregnant Indic hybrid Peizataifeng under two kinds of moisture content(23.43%and 26.07%).Other experiment conditions included the vacuum degree of 2.60 kPa,the rotation speed of seed sucking plate of 30 r/min,three sucking holes with a diameter of 1.6 mm,and the seed layer thickness of 25 *** seeding results showed that,in condition of no more than two seeds per hill,the emergence probabilities under the two moisture contents were 11.82%and 11.95%,respectively,and in condition of 3-4 seeds per hill,the results were 64.81%and 65.84%,*** 2-5 seeds per hill,the results were 92.08%and 92.60%,*** the emergence probability was 80%,under the two moisture contents,the no seed per hill probabilities were 1.33%and 0.80%respectively;the probabilities with 3-4 seeds per hill were 56.13%and 56.40%respectively;the probabilities with 5 or more seeds per hill were 10.67%and 10.13%respectively;the probabilities with 2-5 seeds per hill were 87.60%and 88.13%*** results showed the simulated experiment was an efficient and economic method to assess the capability of pneumatic rice seed drilling metering

关键词： agricultural machinery seeds pneumatic seed metering device precision hill-drop drilling perpendicularity sucking plate rice

Surveillance Video Key Frame Extraction Based on Center Offset

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Computers, Materials & Continua 2021年第9期68卷 4175-4190页

作者： Yunzuo zhang shasha zhang Yi Li Jiayu zhang Zhaoquan Cai Shui Lam School of Information Science and Technology Shijiazhuang Tiedao UniversityShijiazhuang050043 China 2Department of Computer Science and Engineering Huizhou UniversityHuizhou516007 China 3College of Engineering California State UniversityLong BeachCA90185USA

With the explosive growth of surveillance video data,browsing videos quickly and effectively has become an urgent *** key frame extraction has received widespread attention as an effective ***,accurately capturing the local motion state changes of moving objects in the video is still challenging in key frame *** target center offset can reflect the change of its motion *** observation proposed a novel key frame extraction method based on moving objects center offset in this *** proposed method utilizes the center offset to obtain the global and local motion state information of moving objects,and meanwhile,selects the video frame where the center offset curve changes suddenly as the key *** processing effectively overcomes the inaccuracy of traditional key frame extraction ***,extracting the center point of each ***,calculating the center point offset of each frame and forming the center offset curve by connecting the center offset of each ***,extracting candidate key frames and optimizing them to generate final key *** experimental results demonstrate that the proposed method outperforms contrast methods to capturing the local motion state changes of moving objects.

关键词： Center offset local motion key frame extraction moving object detection