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高中生主动性人格与网络学习投入:网络学习自我效能和学业期望的序列中介作用

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心理发展与教育 2024年第2期40卷 224-230页

作者：高斌张丹丹朱根蔡艳香郭羽希上海师范大学教育学院上海200234 湖北医药学院十堰442000 莆田第五中学莆田351100 武汉市第三中学武汉430050

基于社会认知生涯理论考察高中生主动性人格对网络学习投入的影响,以及网络学习自我效能感和学业期望在其中的中介作用。本研究使用主动性人格量表、网络学习自我效能感量表、学业期望量表和网络学习投入量表,对湖北和福建两所中学高一... 详细信息

基于社会认知生涯理论考察高中生主动性人格对网络学习投入的影响,以及网络学习自我效能感和学业期望在其中的中介作用。本研究使用主动性人格量表、网络学习自我效能感量表、学业期望量表和网络学习投入量表,对湖北和福建两所中学高一至高二的477名高中生(高一274人,高二203人)进行问卷调查。结果发现:(1)主动性人格、网络学习自我效能感、学业期望与网络学习投入四个变量相互之间存在显著正相关;(2)主动性人格可以通过三条间接路径对网络学习投入产生影响,即网络学习自我效能的单独中介作用、学业期望的单独中介作用以及网络学习自我效能和学业期望的链式中介作用。研究有助于揭示高中生主动性人格对网络学习投入的作用机制,这为提升其线上学习投入有启示意义。

关键词：高中生主动性人格网络学习自我效能学业期望网络学习投入

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快速干湿气候振荡与中国古代大规模社会动荡

Science Bulletin 2024年第3期69卷 314-318页

作者：孟先强张灿李根程鉴如蔡洁刘一兰霍利倪振宇张恩楼 State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 21008China Department of Earth Science University of CaliforniaSanta Barbara CA 93106USA Ministry of Education Key Laboratory of Surficial Geochemistry School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China

Climate conditions have long been acknowledged as a pivotal factor shaping regional productivity and influencing available resources,consequently playing an important role in driving social changes throughout human history[1–3].In ancient East Asia,the Chinese agrarian civilization emerged around 4000 years ago in northern China,the region termed the“Central Plains”.This region faced recurrent episodes of large-scale social unrest,profoundly impacting the societal structure and dynastic cycles[4].These episodes were marked by extended civil peasant uprisings and/or incursions from northern nomadic tribes,often spanning decades to centuries[5].Both the agrarian societies in the Central Plains and the husbandry-based nomadic tribes in the vast northern grasslands,characterized by semi-arid and semi-humid climates,were notably sensitive to climate variations[6].

关键词： husbandry driving profound

Two New Cardenolide Glycosides from Biondia hemsleyana

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Chinese Chemical Letters 2002年第6期13卷 547-548页

作者： Xing gen TAN Xiao Rong zhang Ming Kui WANG Shu Lin PENG Li sheng DING Chengdu Institute of Biology The Chinese Academy of SciencesChengdu 610041

Two new cardenolide glycosides, biondianosides A and B, were isolated from the roots of endemic plant of Biondia hemsleyana (Warb.) Tsiang. Their structures were elucidated as periplogenin-3-O--D-glucopyranosyl-(16)--D-glucopyranosyl-(14)--D-cymaropyranoside (1) and 17釮-periplogenin-3-O--D-cymaropyranoside (2) by the spectroscopic and chemical methods.

关键词： Biondia hemsleyana cardenolide glycoside biondianosides A and B.

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基于海色融合数据的东海黑潮锋面检测研究

海洋技术学报 2018年第2期37卷 43-49页

作者：施英妮石立坚张高英张根生张春华王伟华北京5111信箱北京100094 国家卫星海洋应用中心北京100081 国家海洋局空间海洋遥感与应用研究重点实验室北京100081

海洋锋是典型的海洋中尺度现象之一。目前卫星遥感主要利用海表温度数据分析海洋锋,但由于西北太平洋海域夏季海表温度的趋同特性,不能进行有效的锋面监测;而不同水团所具有的生物光学特性往往是不同的,且不具有太阳辐射引起的显著性季... 详细信息

海洋锋是典型的海洋中尺度现象之一。目前卫星遥感主要利用海表温度数据分析海洋锋,但由于西北太平洋海域夏季海表温度的趋同特性,不能进行有效的锋面监测;而不同水团所具有的生物光学特性往往是不同的,且不具有太阳辐射引起的显著性季节变化,因此海色资料也成为检测海洋锋的有效数据源。文中以东海黑潮为例,详细说明了基于叶绿素a浓度融合数据,采用梯度法进行海洋锋面检测的过程,通过比较不同季节不同梯度阈值得到的东海黑潮锋结果,从保持锋面的完整性及对零碎锋区的剔除效应方面,选取了不同季节较优的梯度阈值。总体来说,文中检测出的东海黑潮区域海色锋与海流黑潮强流区较吻合,12月至4月东海黑潮海色锋检测结果不如海温锋,而5-11月东海黑潮海色锋检测结果优于海温锋,特别是台湾以东黑潮区域,不论什么季节海温锋都没有体现,而海色锋始终很明显。利用文中提出的海洋锋检测算法、分析方法及选择的梯度阈值可以有效地检测东海黑潮区域的海洋锋面,结合海色锋和海温锋,可以监测分析东海黑潮强流区的时空变化。

关键词：叶绿素a浓度数据融合东海黑潮锋面检测

Brake Orbits of First Order Convex Hamiltonian Systems with Particular Anisotropic Growth

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Acta Mathematica Sinica,English Series 2020年第2期36卷 171-178页

作者： Xiao Fei zhang Chun gen LIU School of Mathematics and Statistics Shanxi Datong UniversityDatong 037009P.R.China School of Mathematics and Information Science Guangzhou UniversityGuangzhou 510006P.R.China

Combining the dual least action principle with Mountain-pass lemma,we obtain the existence of brake orbits for first-order convex Hamiltonian systems with particular anisotropic growth.

关键词： Hamiltonian system brake orbit anisotropic grow th Mountain-pass lemma

Partial intersection sphere decoding with weighted voting for sparse rotated V-OFDM systems

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Science China(Information Sciences) 2018年第2期61卷 77-89页

作者： Qi FENG Xiang-gen XIA Naitong zhang School of Electronic Science and Engineering Nanjing University College of Information Engineering Shenzhen University Department of Electrical and Computer Engineering University of Delaware School of Electronics and Information Engineering Harbin Institute of Technology

Vector orthogonal frequency division multiplexing(V-OFDM) is a general system that builds a bridge between OFDM and single-carrier frequency domain equalization in terms of intersymbol interference level and receiver complexity. In this paper, we focus on a rotated V-OFDM system over a broadband sparse channel owing to its large time delay spread and fewer nonzero taps. In order to collect the multipath diversity,a simple rotation matrix is designed, independent of the number of subchannels at the transmitter. For the rotated V-OFDM receiver, a partial intersection sphere decoding with weighted voting method is proposed by exploiting the sparse nature of the multipath channel. The proposed receiver chooses the transmitted vector from the set with the maximum likelihood estimation generated using the partial intersection sphere decoding method. For an extreme case, such as when a candidate set is empty, which usually occurs at a low signal-to-noise ratio(SNR), an efficient weighted voting system is used to estimate the transmitted vectors symbol-by-symbol. Simulation results indicate that the proposed receiver improves the symbol error rate performance with reduced complexity, especially for low SNR scenarios.

关键词： vector orthogonal frequency division multiplexing sparse multipath channel partial intersection sphere decoding weighted voting diversity order

Using coal fly ash-based geopolymer to immobilize Cd from lead fuming furnace slag

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Rare Metals 2023年第3期42卷 1056-1060页

作者： Bin Guo Bo Liu Shen-gen zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China

Lead fuming furnace slag(LFFS)is a by-product of lead metal production,which is a toxic solid waste according to toxicity characteristic leaching procedure(TCLP)*** was investigated the feasibility of preparation of geopolymer using coal fly ash(CFA)and LFFS and the immobilization efficiency of Cd in *** synthesized geopolymer samples were examined by compressive strength,Fourier transform transmission infrared spectroscopy(FTIR)spectra,X-ray diffraction(XRD)and backscattered electron(BSE)*** is a certain mass ratio(2:3)of the LFFS to the CFA at which the compressive strength of the geopolymeric matrix is the *** test shows that Cd in LFFS can be effectively immobilized in the geopolymer *** is not only a potential technological solution for reusing LFFS but also an effective immobilization method for LFFS treatment and disposal.

关键词： Immobilization Cd Geopolymer Lead fuming furnace slag

RATE OF INTRA-MOLECULAR CONTACT FORMATION IN SHORT TWO-DIMENSIONAL COMPACT POLYMERS CHAINS

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Chinese Journal of Polymer Science 2006年第1期24卷 13-19页

作者： Jin Chen Lin-xi zhang A-gen Xia Department of Physics Zhejiang University Hangzhou 310027 China Department of Physics Wenzhou Normal College Wenzhou 325027 China

It is important to know the rate of intra-molecular contact formation in proteins in order to understand how proteins fold clearly. Here we investigate the rate of intra-molecular contact formation in short two-dimensional compact polymer chains by calculating the probability distribution p（r） of end-to-end distance r using the enumeration calculation method and HP model on two-dimensional square lattice. The probability distribution of end-to-end distance p（r） of short two-dimensional compact polymers chains may consist of two parts, i.e. p（r） = p1（r）＋ p2（r）, where p1（r） and p2（r） are different for small r. The rate of contact formation decreases monotonically with the number of bonds N, and the rate approximately conforms to the scaling relation of k（N）∝ N^-α. Here the value of α increases with the contact radius a and it also depends on the percentage of H （hydrophobic） residues in the sequences of compact chains and the energy parameters of ^εНН、 ^εНН and ^εpp. Some comparisons of theoretical predictions with experimental results are also made. This investigation may help us to understand the protein folding.

关键词： Two-dimensional compact polymer HP model Rate of contact formation.

CP-based MIMO OFDM radar IRCI free range reconstruction using real orthogonal designs

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Science China(Information Sciences) 2017年第2期60卷 40-48页

作者： Tianxian zhang Xiang-gen XIA Lingjiang KONG The School of Electronic Engineering University of Electronic Science and Technology of China The Department of Electrical and Computer Engineering University of Delaware

In this paper, we propose a range reconstruction method for a frequency-band shared multipleinput multiple-output(MIMO) orthogonal frequency-division multiplexing(OFDM) radar with sufficient cyclic prefix(CP) by using real orthogonal designs. Compared with the application of complex orthogonal designs in our previous work, the application of real orthogonal designs can significantly reduce the number of the all-zero-valued pulses in a coherent processing interval(CPI) for each transmitter and increase the efficiency of radar transmitters. Meanwhile, it still maintains the advantages of full spatial diversity without inter-range-cell interference(IRCI). We also apply the rate-1 real orthogonal designs for different numbers of transmitters and pulses for range reconstruction without any idleness of radar transmitters. Simulation results are presented to illustrate the performances of the OFDM pulse design and the CP-based MIMO OFDM radar using real orthogonal designs.

关键词： cyclic prefix(CP) inter-range-cell interference(IRCI) multiple-input multiple-output(MIMO) radar real orthogonal designs orthogonal frequency division multiplexing(OFDM) pulse