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Side-Channel Leakage Analysis of Inner Product Masking
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作者 Yuyuan Li Lang Li Yu Ou 《Computers, Materials & Continua》 SCIE EI 2024年第4期1245-1262,共18页
The Inner Product Masking(IPM)scheme has been shown to provide higher theoretical security guarantees than the BooleanMasking(BM).This scheme aims to increase the algebraic complexity of the coding to achieve a higher... The Inner Product Masking(IPM)scheme has been shown to provide higher theoretical security guarantees than the BooleanMasking(BM).This scheme aims to increase the algebraic complexity of the coding to achieve a higher level of security.Some previous work unfolds when certain(adversarial and implementation)conditions are met,and we seek to complement these investigations by understanding what happens when these conditions deviate from their expected behaviour.In this paper,we investigate the security characteristics of IPM under different conditions.In adversarial condition,the security properties of first-order IPMs obtained through parametric characterization are preserved in the face of univariate and bivariate attacks.In implementation condition,we construct two new polynomial leakage functions to observe the nonlinear leakage of the IPM and connect the security order amplification to the nonlinear function.We observe that the security of IPMis affected by the degree and the linear component in the leakage function.In addition,the comparison experiments from the coefficients,signal-to-noise ratio(SNR)and the public parameter show that the security properties of the IPM are highly implementation-dependent. 展开更多
关键词 Side-channel analysis inner product masking mutual information nonlinear leakage
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Regulating the inner Helmholtz plane structure at the electrolyte-electrode interface for highly reversible aqueous Zn batteries
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作者 Jianghe Liu Sanlue Hu +6 位作者 Hexin Guo Guobin Zhang Wen Liu Jianwei Zhao Shenhua Song Cuiping Han Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期57-67,I0002,共12页
The development of aqueous Zn batteries is limited by parasitic water reactions,corrosion,and dendrite growth.To address these challenges,an inner Helmholtz plane(IHP)regulation method is proposed by employing low-cos... The development of aqueous Zn batteries is limited by parasitic water reactions,corrosion,and dendrite growth.To address these challenges,an inner Helmholtz plane(IHP)regulation method is proposed by employing low-cost,non-toxic maltitol as the electrolyte additive.The preferential adsorption behavior of maltitol can expel the water from the inner Helmholtz plane,and thus hinder the immediate contact between Zn metal and H_(2)O.Meanwhile,strong interaction between maltitol and H_(2)O molecules can restrain the activity of H_(2)O.Besides,the"IHP adsorption effect"along with the low LUMO energy level of maltitol-CF_(3)SO_(3)^(-)can promote the in-situ formation of an organic-inorganic complex solid electrolyte interface(SEI)layer.As a result,the hydrogen/oxygen evolution side reaction,corrosion,and dendrites issues are effectively suppressed,thereby leading to highly reversible and dendrite-free Zn plating/stripping.The Zn‖I_(2)battery with hybrid electrolytes also demonstrates high electrochemical performance and ultralong cycling stability,showing a capacity retention of 75%over 20000 charge-discharge cycles at a large current density of 5 A g^(-1).In addition,the capacity of the device has almost no obvious decay over20000 cycles even at-30℃.This work offers a successful electrolyte regulation strategy via the IHP adsorption effect to design electrolytes for high-performance rechargeable Zn-ion batteries. 展开更多
关键词 inner Helmholtz plane Adsorption effect Dendrite suppression SEI layer Zn||I_(2)battery
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Assessment of land degradation in Inner Mongolia between 2000 and 2020 based on remote sensing data 被引量:2
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作者 Linlin Zhao Kun Jia +2 位作者 Xin Liu Jie Li Mu Xia 《Geography and Sustainability》 CSCD 2023年第2期100-111,共12页
Achieving land degradation neutrality(LDN)worldwide is a significant target of the Sustainable Development Goal(SDG15.3).Inner Mongolia,as a typical dryland region in northern China,has carried out several large-scale... Achieving land degradation neutrality(LDN)worldwide is a significant target of the Sustainable Development Goal(SDG15.3).Inner Mongolia,as a typical dryland region in northern China,has carried out several large-scale ecological restoration programs to combat land degradation.However,there is a lack of comprehensive assess-ment of its land degradation situation after ecological programs implementation,which is of great significance to supporting SDG15.3 in China.This study analyzed the land degradation situation using the improved SDG15.3.1 calculation framework based on fine resolution data in Inner Mongolia from 2000 to 2020,and finally compre-hensively evaluated the land status of the whole region and those subject to ecological programs.The results show that net land restoration proportion of various ecological project regions and whole region continues to increase.The scope of the Grain for Green Program(GGP)had the largest proportion of net land restoration while the Natural Reserve Program(NRP)had the lowest proportion from 2000 to 2020.The net land restoration area of Inner Mongolia during 2000-2010 and 2010-2020 was 35,800 km 2 and 65,300 km 2,respectively.Overall,Inner Mongolia has achieved statistically zero growth in land degradation under the governance of ecological restora-tion programs.Therefore,reasonable planning,well monitoring,and timely assessment of ecological restoration programs are crucial to support SDG15.3. 展开更多
关键词 SDG15.3 Land degradation neutrality(LDN) Land degradation Ecological programs inner Mongolia
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A Survey of Engagement, Subjectivity and Inter-subjectivity
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作者 YU Chao-guo 《Journal of Literature and Art Studies》 2017年第2期201-206,共6页
Engagement and subjectivity focus on the non-propositional meaning of discourse, and inter-subjectivity is concerned with the relationship between a writer/speaker and his potential readers/addressees. This article fi... Engagement and subjectivity focus on the non-propositional meaning of discourse, and inter-subjectivity is concerned with the relationship between a writer/speaker and his potential readers/addressees. This article first introduces the definitions of engagement, subjectivity and inter-subjectivity, and then attempts to discuss the relationships among them. The analysis shows that subjectivity and inter-subjectivity are closely related and that the process of engagement is an interaction of speaking subject and his/her potential readers and social behavior of inter-subjectivity and social practice as well. 展开更多
关键词 ENGAGEMENT SUBJECTIVITY DIALOGUE inter-subjectivity
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Identity Construction Discourse in the Perspective ofInter-Subjectivity-The Case of Address Forms
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作者 Hongce Wang 《教育研究前沿(中英文版)》 2022年第3期45-52,共8页
In daily social communication,people mainly construct their own and others'identities through discourse,and the most representative and widely used of identity-constructing discourse is address forms.In this paper... In daily social communication,people mainly construct their own and others'identities through discourse,and the most representative and widely used of identity-constructing discourse is address forms.In this paper,we focus on the identity-constructing function of address formsand the cognitive collaboration of their subordinate categories at the conceptual level,where different forms of address formshave obvious selection preferences in expressing specific discourse functions.Addressing has a discourse function other than the referential function,and inter-subjectivityis its underlying motivation. 展开更多
关键词 inter-subjectivity Address Forms Identity Construction Discourse
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Enhanced soil moisture improves vegetation growth in an arid grassland of Inner Mongolia Autonomous Region, China
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作者 ZHANG Hui Giri R KATTEL +3 位作者 WANG Guojie CHUAI Xiaowei ZHANG Yuyang MIAO Lijuan 《Journal of Arid Land》 SCIE CSCD 2023年第7期871-885,共15页
Climate change impacts on grasslands that cover a quarter of the global land area, have become unprecedented during the 21~(st) century. One of the important ecological realms, arid grasslands of northern China, which... Climate change impacts on grasslands that cover a quarter of the global land area, have become unprecedented during the 21~(st) century. One of the important ecological realms, arid grasslands of northern China, which occupy more than 70% of the region's land area. However, the impact of climate change on vegetation growth in these arid grasslands is not consistent and lacks corresponding quantitative research. In this study, NDVI(normalized difference vegetation index) and climate factors including temperature, precipitation, solar radiation, soil moisture, and meteorological drought were analyzed to explore the determinants of changes in grassland greenness in Inner Mongolia Autonomous Region(northern China) during 1982–2016. The results showed that grasslands in Inner Mongolia witnessed an obvious trend of seasonal greening during the study period. Two prominent climatic factors,precipitation and soil moisture accounted for approximately 33% and 27% of grassland NDVI trends in the region based on multiple linear regression and boosted regression tree methods. This finding highlights the impact of water constraints to vegetation growth in Inner Mongolia's grasslands. The dominant role of precipitation in regulating grassland NDVI trends in Inner Mongolia significantly weakened from 1982 to 1996, and the role of soil moisture strengthened after 1996. Our findings emphasize the enhanced importance of soil moisture in driving vegetation growth in arid grasslands of Inner Mongolia, which should be thoroughly investigated in the future. 展开更多
关键词 grassland growth normalized difference vegetation index climate change soil moisture inner Mongolia
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Modeling the energetic electron fluxes in the inner radiation belt based on a drift-source model
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作者 Zheng Xiang BinBin Ni +8 位作者 YangXiZi Liu XuDong Gu Song Fu Wei Xu Xing Cao Xin Ma DeYu Guo JunHu Dong JingLe Hu 《Earth and Planetary Physics》 EI CSCD 2023年第1期100-108,共9页
The Macao Science Satellite-1(MSS-1),designed by the Macao University of Science and Technology and the National Space Science Center(NSSC)of China,is equipped to detect the fine structure of the magnetic field over t... The Macao Science Satellite-1(MSS-1),designed by the Macao University of Science and Technology and the National Space Science Center(NSSC)of China,is equipped to detect the fine structure of the magnetic field over the South Atlantic Anomaly(SAA)region,monitoring geomagnetic field variations,and obtaining the energetic electron spectrum distributions in the Earth’s inner radiation belt.In this study,we simulate the distributions of trapped,quasi-trapped,and untrapped electrons along the orbit of MSS-1 based on a drift-source model.The simulation results show that the particle detector with 90°looking direction can observe trapped electrons in the SAA region,untrapped electrons in the regions conjugated with the SAA region at the north hemisphere,and quasitrapped electrons in all other regions.In contrast,the detectors with<60°looking directions can measure only untrapped electrons.Generally,quasi-trapped electron fluxes accumulate along the drift trajectory and are due primarily to CRAND,until reaching the SAA region where quasi-trapped electrons are all lost into the atmosphere. 展开更多
关键词 Earth’s inner belt drift-source model quasi-trapped electron CRAND
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Responses of vegetation yield to precipitation and reference evapotranspiration in a desert steppe in Inner Mongolia,China
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作者 LI Hongfang WANG Jian +2 位作者 LIU Hu MIAO Henglu LIU Jianfeng 《Journal of Arid Land》 SCIE CSCD 2023年第4期477-490,共14页
Drought,which restricts the sustainable development of agriculture,ecological health,and social economy,is affected by a variety of factors.It is widely accepted that a single variable cannot fully reflect the charact... Drought,which restricts the sustainable development of agriculture,ecological health,and social economy,is affected by a variety of factors.It is widely accepted that a single variable cannot fully reflect the characteristics of drought events.Studying precipitation,reference evapotranspiration(ET_(0)),and vegetation yield can derive information to help conserve water resources in grassland ecosystems in arid and semi-arid regions.In this study,the interactions of precipitation,ET_(0),and vegetation yield in Darhan Muminggan Joint Banner(DMJB),a desert steppe in Inner Mongolia Autonomous Region,China were explored using two-dimensional(2D)and three-dimensional(3D)joint distribution models.Three types of Copula functions were applied to quantitatively analyze the joint distribution probability of different combinations of precipitation,ET_(0),and vegetation yield.For the precipitation–ET_(0)dry–wet type,the 2D joint distribution probability with precipitation≤245.69 mm/a or ET_(0)≥959.20 mm/a in DMJB was approximately 0.60,while the joint distribution probability with precipitation≤245.69 mm/a and ET_(0)≥959.20 mm/a was approximately 0.20.Correspondingly,the joint return period that at least one of the two events(precipitation was dry or ET_(0)was wet)occurred was 2 a,and the co-occurrence return period that both events(precipitation was dry and ET_(0)was wet)occurred was 5 a.Under this condition,the interval between dry and wet events would be short,the water supply and demand were unbalanced,and the water demand of vegetation would not be met.In addition,when precipitation remained stable and ET_(0)increased,the 3D joint distribution probability that vegetation yield would decrease due to water shortage in the precipitation–ET_(0)dry–wet years could reach up to 0.60–0.70.In future work,irrigation activities and water allocation criteria need to be implemented to increase vegetation yield and the safety of water resources in the desert steppe of Inner Mongolia. 展开更多
关键词 PRECIPITATION reference evapotranspiration vegetation yield Copula functions desert steppe dry and wet events inner Mongolia
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Spatial changes and driving factors of lake water quality in Inner Mongolia, China
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作者 REN Xiaohui YU Ruihong +10 位作者 LIU Xinyu SUN Heyang GENG Yue QI Zhen ZHANG Zhuangzhuang LI Xiangwei WANG Jun ZHU Penghang GUO Zhiwei WANG Lixin XU Jifei 《Journal of Arid Land》 SCIE CSCD 2023年第2期164-179,共16页
Lakes play important roles in sustaining the ecosystem and economic development in Inner Mongolia Autonomous Region of China,but the spatial patterns and driving mechanisms of water quality in lakes so far remain uncl... Lakes play important roles in sustaining the ecosystem and economic development in Inner Mongolia Autonomous Region of China,but the spatial patterns and driving mechanisms of water quality in lakes so far remain unclear.This study aimed to identify the spatial changes in water quality and the driving factors of seven lakes(Juyanhai Lake,Ulansuhai Lake,Hongjiannao Lake,Daihai Lake,Chagannaoer Lake,Hulun Lake,and Wulannuoer Lake)across the longitudinal axis(from the west to the east)of Inner Mongolia.Large-scale research was conducted using the comprehensive trophic level index(TLI(Σ)),multivariate statistics,and spatial analysis methods.The results showed that most lakes in Inner Mongolia were weakly alkaline.Total dissolved solids and salinity of lake water showed obvious zonation characteristics.Nitrogen and phosphorus were identified as the main pollutants in lakes,with high average concentrations of total nitrogen and total phosphorus being of 4.05 and 0.21 mg/L,respectively.The values of TLI(Σ)ranged from 49.14 to 71.77,indicating varying degrees of lake eutrophication,and phosphorus was the main driver of lake eutrophication.The lakes of Inner Mongolia could be categorized into lakes to the west of Daihai Lake and lakes to the east of Daihai Lake in terms of salinity and TLI(Σ).The salinity levels of lakes to the west of Daihai Lake exceeded those of lakes to the east of Daihai Lake,whereas the opposite trend was observed for lake trophic level.The intensity and mode of anthropogenic activities were the driving factors of the spatial patterns of lake water quality.It is recommended to control the impact of anthropogenic activities on the water quality of lakes in Inner Mongolia to improve lake ecological environment.These findings provide a more thorough understanding of the driving mechanism of the spatial patterns of water quality in lakes of Inner Mongolia,which can be used to develop strategies for lake ecosystem protection and water resources management in this region. 展开更多
关键词 SALINITY lake eutrophication lake water quality comprehensive trophic level index anthropogenic activities Daihai Lake inner Mongolia
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The Inner Structure of the Intrinsic Electron and the Origin of Self-Mass
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作者 Victor Vaguine 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期174-189,共16页
A brief review and analysis of two historical models of the electron, the charged spinning sphere and Goudsmit and Uhlenbeck’s concept, is presented. It is shown that the enormous potential of classical electrodynami... A brief review and analysis of two historical models of the electron, the charged spinning sphere and Goudsmit and Uhlenbeck’s concept, is presented. It is shown that the enormous potential of classical electrodynamics has been underutilized in particle physics. Such observation leads to discovery of a principal component in the electron inner structure—the charged c-ring. The intrinsic (fundamental) electron model based on the charged c-ring successfully explains the ontology of the charge fractionation in quantum chromodynamics and the formation of Cooper pairs in superconductivity. The c-ring properties are explained on the basis of the General Compton Conditions as defined. Properties of the charged c-ring include the explanation of the boundary conditions, electro-magnetostatic field configuration, self-mass, spin, magnetic moment, and the gyromagnetic ratio. The self-mass of the intrinsic electron is 100% electro-magnetostatic and it is shown how to compute its value. The classical-quantum divide no longer exists. Relation between the intrinsic electron and the electron is fundamentally defined. The electron is the composite fermion consisting of the intrinsic electron and the neutrino. The ontology of the anomaly in the electron magnetic moment is demonstrated—it is due to the addition of the neutrino magnetic moment to the overall electron magnetic moment. The intrinsic electron replaces the W? boson in particle physics, resulting in a fundamental implication for the Standard Model. 展开更多
关键词 Intrinsic Electron inner Structure Electro-Magnetostatic Self-Mass General Compton Conditions Charged C-Ring Visualization C-Ring Length Constant
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The Intrinsic Electron with Its Properties Such as Inner Structure and Self-Mass Is in Conflict with Quantum Field Theory
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作者 Victor Vaguine 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第3期583-595,共13页
The quantum field theory (QFT) is one of branches of the Standard Model. According to QFT, quantum fields are the primary entities and particles are the excitations of these fields, coming in discrete lumps with no in... The quantum field theory (QFT) is one of branches of the Standard Model. According to QFT, quantum fields are the primary entities and particles are the excitations of these fields, coming in discrete lumps with no inner structures and with properties assigned by declaration. Such view is in conflict with the observed vacuum energy density, 140 orders of magnitudes less than required by the QFT. In addition, such view is challenged by Aphysical Quantum Mechanics (AQM), a deeper quantum theory. According to AQM, the fundamental understanding of quantum reality is expanded by the addition of two fundamental categories, aphysical and elementary consciousness of elementary particles. Based on AQM and as an example, the total ontology of the intrinsic (fundamental) electron is presented with its inner structure of perfect geometry consisting of the physical charged c-ring and aphysical cylinder, and with its properties such as self-mass, spin, magneto-electrostatic field configuration and magnetic moment. The position parameter in the inner structure demonstrates that there are no two identical intrinsic electrons in the Universe thus placing a question mark over the QFT principle of indistinguishability. 展开更多
关键词 Quantum Reality Physical-Aphysical Intrinsic Electron Charged C-Ring Aphysical Cylinder Elementary Consciousness Position Parameter Constant U Ontology Self-Mass Indistinguishable inner Structure
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基于改进凸内逼近法的主动配电网有功-无功协调优化 被引量:1
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作者 黄永红 王玉祥 +3 位作者 孔维健 曹程 苏家宇 王克威 《中国电机工程学报》 EI CSCD 北大核心 2024年第14期5528-5537,I0007,共11页
以风电、光伏为代表的分布式电源接入配电网后容易导致系统电压波动变大以及局部电压越限。以二阶锥优化为代表的松弛技术在优化时为了保证松弛后解的精确,约束条件极为严苛并且在功率的极端注入下容易导致对偶间隙增大。针对上述问题,... 以风电、光伏为代表的分布式电源接入配电网后容易导致系统电压波动变大以及局部电压越限。以二阶锥优化为代表的松弛技术在优化时为了保证松弛后解的精确,约束条件极为严苛并且在功率的极端注入下容易导致对偶间隙增大。针对上述问题,该文提出基于改进凸内逼近法的主动配电网有功-无功优化方法。首先,基于支路潮流方程定义与支路电流、节点电压和视在功率流相关的非线性项的凸包,并与剩余线性元素结合形成凸内部近似,建立完善的数学模型;进一步提出网络容许性判据以及引入KKT条件收缩最优解的对偶间隙。最后,基于IEEE 33系统及PG&E69节点系统,利用Yalmip等平台求得电网中各有功、无功决策变量的出力区间,验证所提方法的稳定、精确与高效性。 展开更多
关键词 分布式电源 凸内逼近 电压 调度区域
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滚子与内圈打滑行为诱导的振动特性 被引量:1
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作者 马德锋 孙琦 +2 位作者 孙军栋 雷浩伟 刘公平 《轴承》 北大核心 2024年第1期86-91,共6页
针对滚子打滑试验研究困难的问题,通过分析滚子-内圈运动副的相对运动关系得出运动副振动特征频率的计算公式,在此基础上开展打滑试验,提取滚子纯滚动、打滑状态下的振动信号并采用短时傅里叶变换进行时频域分析,结果表明:滚子打滑会诱... 针对滚子打滑试验研究困难的问题,通过分析滚子-内圈运动副的相对运动关系得出运动副振动特征频率的计算公式,在此基础上开展打滑试验,提取滚子纯滚动、打滑状态下的振动信号并采用短时傅里叶变换进行时频域分析,结果表明:滚子打滑会诱发一定的振动响应,其频率与滚子、内圈的转动频率相关,理论计算结果与试验结果较为吻合,可用于测算滚子打滑程度;滚子由纯滚动状态转变为打滑状态或由打滑状态转变为纯滚动状态时,纵向、切向振动的幅值均会发生突变,切向振动信号占主要成分且幅值更大。 展开更多
关键词 滚动轴承 滚子 内圈 打滑 振动 频率 动力学分析
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内蒙古智慧农业高质量发展机遇与对策 被引量:1
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作者 谢岷 李丽君 +4 位作者 吴强 张鹏 樊丽 矫娇娇 于晓芳 《智慧农业导刊》 2024年第9期1-4,共4页
智慧农业已成为现代农业最重要的发展方向之一,是以智慧化和智能化为目标,通过互联网、物联网、大数据、云计算和人工智能等现代信息技术与农业跨界融合,实现农业生产全过程的信息感知、定量决策、智能控制、精准投入和个性化服务的全... 智慧农业已成为现代农业最重要的发展方向之一,是以智慧化和智能化为目标,通过互联网、物联网、大数据、云计算和人工智能等现代信息技术与农业跨界融合,实现农业生产全过程的信息感知、定量决策、智能控制、精准投入和个性化服务的全新农业生产方式。内蒙古作为我国重要的粮食主产区和粮食净调出省区之一,大力推进智慧农业建设,积极探索智慧农业新技术、新模式、新实践对促进内蒙古智慧农业高质量发展至关重要。 展开更多
关键词 内蒙古 智慧农业 高质量发展 机遇 对策
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中国特色现代教育学话语体系解析 被引量:1
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作者 侯怀银 王钰捷 《宁波大学学报(教育科学版)》 2024年第2期1-10,共10页
中国特色现代教育学话语体系是以马克思主义为指导,以中华优秀传统文化为底色,在中国教育理论与教育实践的土壤中形成的,用中国的思维和方式对教育学概念、范畴、表述等进行系统阐述的言语表达系统。中国特色现代教育学话语体系由话语... 中国特色现代教育学话语体系是以马克思主义为指导,以中华优秀传统文化为底色,在中国教育理论与教育实践的土壤中形成的,用中国的思维和方式对教育学概念、范畴、表述等进行系统阐述的言语表达系统。中国特色现代教育学话语体系由话语立场、话语主体、话语客体、话语内容、话语传播五大要素组成。中国特色现代教育学话语体系形成有其特定的理论逻辑、历史逻辑、实践逻辑和文化逻辑;其发展又呈现出内在发展规律,主要表现为:以历史为基、以时代为脉,促进教育学理论研究与实践变革的双向建构;抒人民之情、表人民之意,人民性贯穿于话语体系的始终;以中国为点、以世界为面,教育学话语体系向内生发的同时注重向外传播。 展开更多
关键词 中国特色现代教育学 教育学话语体系 概念 组成要素 内在逻辑
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毫米波多内导体布喇格结构电磁特性研究
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作者 丁学用 王石峰 +1 位作者 王连胜 袁帅 《电波科学学报》 CSCD 北大核心 2024年第1期142-147,共6页
基于多模耦合理论,利用三维电磁仿真软件CST对毫米波双内导体和三内导体布喇格结构电磁特性分别进行了比较研究。结果表明:双内导体布喇格结构相比同轴布喇格结构可以抑制竞争模式,反射率稳定并接近1,对称性结构电磁特性优于非对称性结... 基于多模耦合理论,利用三维电磁仿真软件CST对毫米波双内导体和三内导体布喇格结构电磁特性分别进行了比较研究。结果表明:双内导体布喇格结构相比同轴布喇格结构可以抑制竞争模式,反射率稳定并接近1,对称性结构电磁特性优于非对称性结构;随着内导体距离同轴轴心距离的增大,双内导体布喇格结构频率响应带宽变宽,且当内导体距离同轴轴心距离较远时,带宽变宽趋势明显,而反射率值趋于稳定;对于三内导体布喇格结构,随着内导体距离同轴轴心距离的增大,频率响应带宽变窄,且当内导体距离同轴轴心距离较近时,带宽变宽趋势明显。因此,可根据实际需要恰当选择毫米波多内导体布喇格结构参数,拓宽其作为反射器或者滤波器的性能,提高模式的选择性及模式的纯度,改善布喇格结构的性能。 展开更多
关键词 同轴布喇格结构 双内导体结构 三内导体结构 频率响应 电场分布云图
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烟用框架纸应用现状与性能指标分析
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作者 陈宸 杨芳 +7 位作者 李青常 叶长文 濮厚庆 张玮韬 谭明杰 牛佳佳 李栋 葛畅 《中国造纸》 CAS 北大核心 2024年第5期109-115,共7页
烟用框架纸是重要的卷烟包装材料,具有保护卷烟等作用。本文首先介绍了烟用框架纸产品的技术发展和应用情况;然后重点分析了烟用框架纸的主要性能指标,并对行业代表性样品开展了性能指标普查测试研究,评价了烟用框架纸产品的整体质量水... 烟用框架纸是重要的卷烟包装材料,具有保护卷烟等作用。本文首先介绍了烟用框架纸产品的技术发展和应用情况;然后重点分析了烟用框架纸的主要性能指标,并对行业代表性样品开展了性能指标普查测试研究,评价了烟用框架纸产品的整体质量水平;最后展望了烟用框架纸产品的发展方向。 展开更多
关键词 烟用框架纸 产品现状 性能指标 普查测试 发展方向
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光致变色纱线在多层织物设计中的应用
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作者 牛建涛 刘雨晴 +2 位作者 黄紫娟 徐超武 蒋秀翔 《毛纺科技》 CAS 北大核心 2024年第1期15-18,共4页
为了丰富织物的多样性,利用光致变色纱线,结合表里换层双层组织,设计与开发了“P”字图案表里换层光致变色面料;并进一步设计与开发了上、中层表里换层结构的“E”字图案三层组织光致变色面料,实现了织物在光线照射下单面变色,而反面不... 为了丰富织物的多样性,利用光致变色纱线,结合表里换层双层组织,设计与开发了“P”字图案表里换层光致变色面料;并进一步设计与开发了上、中层表里换层结构的“E”字图案三层组织光致变色面料,实现了织物在光线照射下单面变色,而反面不显变色的特殊效果。将光致变色纱线与表里换层结构的双层或多层织物相结合,可以形成新型光致变色功能面料,为此类产品的开发与设计提供了一种新思路。 展开更多
关键词 光致变色 表里换层 多层织物 产品设计
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轴向移动内压力梁动力学的动网格法
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作者 郑伶俐 华洪良 +2 位作者 吴小锋 蔡宪逸 廖振强 《兵器装备工程学报》 CAS CSCD 北大核心 2024年第3期50-56,共7页
面向轴向移动内压力梁结构动力学特性研究,采用Lagrangian方法建立了轴向移动内压力梁的运动控制方程,基于有限元动网格法对轴向移动梁运动控制方程进行离散。将内压力作为边界条件,采用Newmark-β时间积分方法计算轴向移动梁动力学响应... 面向轴向移动内压力梁结构动力学特性研究,采用Lagrangian方法建立了轴向移动内压力梁的运动控制方程,基于有限元动网格法对轴向移动梁运动控制方程进行离散。将内压力作为边界条件,采用Newmark-β时间积分方法计算轴向移动梁动力学响应,并开展动力学特性研究。结果表明,建立的有限元动网格模型能够有效地实现轴向移动内压力梁动力学响应计算。轴向移动内压力梁在收缩运动过程中,自由端振动频率将逐渐增加。悬臂长度对梁自由端振动频率具有显著影响。同时,结构振动频率随内压力的增加而增加。本文中建立的有限元动网格模型能够为轴向移动内压力梁动力学研究提供新方法。 展开更多
关键词 轴向移动梁 动网格法 内压力 有限元法
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新一轮财税体制改革的内在逻辑和建议 被引量:1
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作者 张俊伟 《财政科学》 2024年第2期11-16,共6页
本文从财税体制改革的内在逻辑、高质量发展新要求、“后土地财政”时代来临三方面入手,分析了当前我国财政运行面临的突出矛盾、归纳了新一轮财税体制改革的主要任务及面临的约束条件,提出了新一轮财税体制改革应坚持的基本原则和主要... 本文从财税体制改革的内在逻辑、高质量发展新要求、“后土地财政”时代来临三方面入手,分析了当前我国财政运行面临的突出矛盾、归纳了新一轮财税体制改革的主要任务及面临的约束条件,提出了新一轮财税体制改革应坚持的基本原则和主要改革措施建议。 展开更多
关键词 新一轮财税体制改革 高质量发展 内在逻辑
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