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Identification of unconditional and conditional QTL for oil, protein and starch content in maize 被引量:10
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作者 Yuqiu Guo Xiaohong Yang +4 位作者 Subhash Chander Jianbing Yan Jun Zhang Tongming Song Jiansheng Li 《The Crop Journal》 SCIE CAS 2013年第1期34-42,共9页
Oil, protein and starch are key chemical components of maize kernels. A population of 245 recombinant inbred lines(RILs) derived from a cross between a high-oil inbred line, By804, and a regular inbred line, B73, was ... Oil, protein and starch are key chemical components of maize kernels. A population of 245 recombinant inbred lines(RILs) derived from a cross between a high-oil inbred line, By804, and a regular inbred line, B73, was used to dissect the genetic interrelationships among oil, starch and protein content at the individual QTL level by unconditional and conditional QTL mapping. Combined phenotypic data over two years with a genetic linkage map constructed using 236 markers, nine, five and eight unconditional QTL were detected for oil, protein and starch content, respectively. Some QTL for oil, protein and starch content were clustered in the same genomic regions and the direction of their effects was consistent with the sign of their correlation. In conditional QTL mapping, 37(29/8) unconditional QTL were not detected or showed reduced effects, four QTL demonstrated similar effects under unconditional and conditional QTL mapping, and 17 additional QTL were identified by conditional QTL mapping. These results imply that there is a strong genetic relationship among oil, protein and starch content in maize kernels. The information generated in the present investigation could be helpful in marker-assisted breeding for maize varieties with desirable kernel quality traits. 展开更多
关键词 ZEA mays OIL Protein STARCH unconditional QTL CONDITIONAL QTL
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Unconditional and Conditional QTL Mapping for Tiller Numbers at Various Stages with Single Segment Substitution Lines in Rice(Oryza sativa L.) 被引量:6
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作者 ZHAO Fang-ming LIU Gui-fu ZHU Hai-tao DING Xiao-hua ZENG Rui-zhen ZHANG Ze-min LI Wen-tao ZHANG Gui-quan 《Agricultural Sciences in China》 CAS CSCD 2008年第3期257-265,共9页
Tiller is one of the most important agronomic traits which influences quantity and quality of effective panicles and finally influences yield in rice. It is important to understand "static" and "dynamic" informati... Tiller is one of the most important agronomic traits which influences quantity and quality of effective panicles and finally influences yield in rice. It is important to understand "static" and "dynamic" information of the QTLs for tillers in rice. This work was the first time to simultaneously map unconditional and conditional QTLs for tiller numbers at various stages by using single segment substitution lines in rice. Fourteen QTLs for tiller number, distributing on the corresponding substitution segments of chromosomes 1, 2, 3, 4, 6, 7 and 8 were detected. Both the number and the effect of the QTLs for tiller number were various at different stages, from 6 to 9 in the number and from 1.49 to 3.49 in the effect, respectively. Tiller number QTLs expressed in a time order, mainly detected at three stages of 0-7 d, 14-21 d and 35-42 d after transplanting with 6 positive, 9 random and 6 negative expressing QTLs, respectively. Each of the QTLs expressed one time at least during the whole duration of rice. The tiller number at a specific stage was determined by sum of QTL effects estimated by the unconditional method, while the increasing or decreasing number in a given time interval was controlled by the total of QTL effects estimated by the conditional method. These results demonstrated that it is highly effective and accurate for mapping of the QTLs by using single segment substitution lines and the conditional analysis methodology. 展开更多
关键词 single segment substitution line unconditional QTL mapping conditional QTL mapping tiller number RICE
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The Unconditional Stability for the Hyperneutral Type Constant Linear Control System with Delays (I) 被引量:3
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作者 Li Ye-ping Meng Pei-yuan Zhou Guo-peng 《Wuhan University Journal of Natural Sciences》 EI CAS 2001年第4期759-763,共5页
By means of the frequency domain method and the inequality analysis, we discuss the unconditional stability problem for the hyperneutral type constant linear control system with delays, and obtain some precise suffici... By means of the frequency domain method and the inequality analysis, we discuss the unconditional stability problem for the hyperneutral type constant linear control system with delays, and obtain some precise sufficient, sufficient and necessary conditions. 展开更多
关键词 DELAYS hyperneutral type unconditional stability
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Conditional and unconditional QTLs mapping of gluten strength in common wheat (Triticum aestivum L.) 被引量:2
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作者 LIU Tong-tong LIU Kai +6 位作者 WANG Fang-fang ZHANG Ying LI Qing-fang ZHANG Kai-ran XIE Chu-peng TIAN Ji-chun CHEN Jian-sheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第10期2145-2155,共11页
Dissecting the genetic relationships among gluten-related traits is important for high quality wheat breeding. Quantita- tive trait loci (QTLs) analysis for gluten strength, as measured by sedimentation volume (SV... Dissecting the genetic relationships among gluten-related traits is important for high quality wheat breeding. Quantita- tive trait loci (QTLs) analysis for gluten strength, as measured by sedimentation volume (SV) and gluten index (GI), was performed using the QTLNetwork 2.0 software. Recombinant inbred lines (RILs) derived from the winter wheat varieties Shannong 01-35xGaocheng 9411 were used for the study. A total of seven additive QTLs for gluten strength were identi- fied using an unconditional analysis. QGi1D-13 and QSv1D-14 were detected through unconditional and conditional QTLs mapping, which explained 9.15-45.08% of the phenotypic variation. QTLs only identified under conditional QTL mapping were located in three marker intervals: WPT-3743-GLU-D1 (1D), WPT-7001-WMC258 (1B), and WPT-8682-WPT-5562 (1B). Six pairs of epistatic QTLs distributed nine chromosomes were identified. Of these, two main effect QTLs (QGi1D-13 and QSvlD-14) and 12 pairs of epistatic QTLs were involved in interactions with the environment. The results indicated that chromosomes 1B and 1D are important for the improvement of gluten strength in common wheat. The combination of conditional and unconditional QTLs mapping could be useful for a better understanding of the interdependence of different traits at the QTL molecular level. 展开更多
关键词 wheat (Triticum aestivum L.) gluten strength gluten index sedimentation volume unconditional QTL mapping conditional QTL mapping
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THE UNCONDITIONAL STABILITY FOR THE HYPERNEUTRAL TYPE CONSTANT LINEAR CONTROL SYSTEM WITH DELAYS 被引量:1
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作者 黎野平 张少华 《Acta Mathematica Scientia》 SCIE CSCD 2001年第4期546-552,共7页
In this paper, by means of the frequency domain method and the inequality analysis, unconditional stability problem for the hyperneutral type constant linear control system with delays are discussed, and some precise ... In this paper, by means of the frequency domain method and the inequality analysis, unconditional stability problem for the hyperneutral type constant linear control system with delays are discussed, and some precise sufficient, sufficient and necessary conditions are obtained. 展开更多
关键词 DELAY hyperneutral type unconditional stability
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The Unconditional Stability for the Multigroup Multidelays Neutral Type Linear Constant Control System 被引量:1
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作者 LI Ye ping College of Mathematics and Computer Science, Wuhan University, Wuhan,430072, China 《Wuhan University Journal of Natural Sciences》 CAS 1999年第4期382-386,共5页
Applying the frequency domain method and the inequality method, we discussed the unconditional stability problem of the multigroup multidelays neutral type linear constant continuous control system, and obtained some ... Applying the frequency domain method and the inequality method, we discussed the unconditional stability problem of the multigroup multidelays neutral type linear constant continuous control system, and obtained some sufficient conditions. 展开更多
关键词 multidelays neutral type unconditional stability
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Nonlinear evaluations of unconditionally stable explicit algorithms 被引量:1
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作者 Shuenn-Yih Chang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第3期329-340,共12页
Two explicit integration algorithms with unconditional stability for linear elastic systems have been successfully developed for pseudodynamic testing. Their numerical properties in the solution of a linear elastic sy... Two explicit integration algorithms with unconditional stability for linear elastic systems have been successfully developed for pseudodynamic testing. Their numerical properties in the solution of a linear elastic system have been well explored and their applications to the pseudodynamic testing of a nonlinear system have been shown to be feasible. However, their numerical properties in the solution of a nonlinear system are not apparent. Therefore, the performance of both algorithms for use in the solution of a nonlinear system has been analytically evaluated after introducing an instantaneous degree of nonlinearity. The two algorithms have roughly the same accuracy for a small value of the product of the natural frequency and step size. Meanwhile, the first algorithm is unconditionally stable when the instantaneous degree of nonlinearity is less than or equal to 1, and it becomes conditionally stable when it is greater than 1. The second algorithm is conditionally stable as the instantaneous degree of nonlinearity is less than 1/9, and becomes unstable when it is greater than 1. It can have unconditional stability for the range between 1/9 and 1. Based on these evaluations, it was concluded that the first algorithm is superior to the second one. Also, both algorithms were found to require commensurate computational efforts, which are much less than needed for the Newmark explicit method in general structural dynamic problems. 展开更多
关键词 explicit integration algorithms unconditional stability pseudodynamic algorithm nonlinear system instantaneous degree of nonlinearity
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A two-step unconditionally stable explicit method with controllable numerical dissipations
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作者 Li Jinze Yu Kaiping Li Xiangyang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第2期285-299,共15页
A family of unconditionally stable direct integration algorithm with controllable numerical dissipations is proposed. The numerical properties of the new algorithms are controlled by three parameters α, β and γ. By... A family of unconditionally stable direct integration algorithm with controllable numerical dissipations is proposed. The numerical properties of the new algorithms are controlled by three parameters α, β and γ. By the consistent and stability analysis, the proposed algorithms achieve the second-order accuracy and are unconditionally stable under the condition that α≥-0.5, β≤ 0.5 and γ≥-(1+α)/2. Compared with other unconditionally stable algorithms, such as Chang's algorithms and CR algorithm, the proposed algorithms are found to be superior in terms of the controllable numerical damping ratios. The unconditional stability and numerical damping ratios of the proposed algorithms are examined by three numerical examples. The results demonstrate that the proposed algorithms have a superior performance and can be used expediently in solving linear elastic dynamics problems. 展开更多
关键词 DIRECT INTEGRATION method unconditional STABILITY NUMERICAL DISSIPATION dynamic analysis
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THE SUFFICIENT AND NECESSARY CONDITIONS OF UNCONDITIONAL STABILITY AND THE DELAY BOUND OF THE THIRD-ORDER NEUTRAL DELAY DIFFERENTIAL EQUATION
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作者 陈均平 李志勇 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1991年第7期681-685,共5页
In this paper, the sufficient and necessary conditions of the unconditional stability, and the delay bound of the third-order neutral delay differential equation with real constant coefficients are given. The conditio... In this paper, the sufficient and necessary conditions of the unconditional stability, and the delay bound of the third-order neutral delay differential equation with real constant coefficients are given. The conditions are brief and practical algebraic criterions Furthermore, we get the delay bound. 展开更多
关键词 differential-difference equations unconditional stability algebraic criterion
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Unconditional Positive Self-Regard (UPSR) and Self-Compassion, the Internal Consistency and Convergent/Divergent Validity of Patterson &Joseph’s UPSR Scale
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作者 Laura Jayne Griffiths Christopher Alan Griffiths 《Open Journal of Medical Psychology》 2013年第4期168-174,共7页
Objectives: The purpose of this study is to test the psychometric properties and validity of the unconditional positive self-regard scale (UPSR) and its two subscales developed by Patterson & Joseph (2006). It als... Objectives: The purpose of this study is to test the psychometric properties and validity of the unconditional positive self-regard scale (UPSR) and its two subscales developed by Patterson & Joseph (2006). It also aims to examine and compare the concepts of UPSR with self-compassion and its relation to mental well-being. Design: Correlation survey design validations of the UPSR scale (Patterson & Joseph, 2006). Methods: The validation was conducted using an undergraduate and postgraduate student opportunity sample, n = 179. Internal consistency was assessed using Cronbach’s coefficient alpha and inter-item correlations. Convergent and divergent validity was explored in terms of correlations with self-compassion, depression (PHQ-9) and anxiety (GAD-7) scales. Results: There was good internal consistency for both the UPSR scale and the self-regard subscale and somewhat questionable internal consistency for the conditionality subscale. Overall the scale appears to be relatively consistent, supporting the previous findings reported by Patterson & Joseph (2006). The results supported the hypothesis that UPSR is positively correlated with a measure of self-compassion and negatively correlated with measures of depression (PHQ-9) and anxiety (GAD-7). Conclusions: The UPSR scale is a valid measure of the person-centred concept of unconditional positive self-regard. This supports the potential use of the UPSR scale for evaluating therapeutic change for client-centred practitioners through the use of this non-medicalized tool. 展开更多
关键词 unconditional POSITIVE Self-Regard PSYCHOTHERAPY SELF-COMPASSION Carl ROGERS
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Asymptotic properties of two affine invariants for 1-unconditional convex bodies
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作者 谢富生 何斌吾 易军 《Journal of Shanghai University(English Edition)》 CAS 2010年第3期223-227,共5页
Let K be a 1-unconditional convex bodies in Euclidean spaces.We study the asymptotic properties of two affine invariants m2(K) and S2(K) for a random simplex inside K.As an application,we discuss the asymptotic pr... Let K be a 1-unconditional convex bodies in Euclidean spaces.We study the asymptotic properties of two affine invariants m2(K) and S2(K) for a random simplex inside K.As an application,we discuss the asymptotic properties of two affine invariants m2(Bpn ) and S2(Bpn ),where Bpn = {x ∈ Rn : ‖x‖ p 1}. 展开更多
关键词 convex body 1-unconditional convex body isotropic constant Sylvester’s problem random simplex
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单步无条件稳定显式结构动力学算法
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作者 李常青 李正藩 蒋丽忠 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第3期1136-1145,共10页
在结构动力学分析中,数值积分方法通常被用来高效和准确地求解复杂结构系统在动态负载下的响应。基于量纲分析的原理,提出一种求解结构动力学问题的单步无条件稳定显式算法。首先对所构造的关于位移和速度的函数关系式进行无量纲化处理... 在结构动力学分析中,数值积分方法通常被用来高效和准确地求解复杂结构系统在动态负载下的响应。基于量纲分析的原理,提出一种求解结构动力学问题的单步无条件稳定显式算法。首先对所构造的关于位移和速度的函数关系式进行无量纲化处理,然后通过算法精度要求、无条件稳定条件和数值阻尼可控条件确定了其最终递推格式,并根据算法最终递推格式分析得出算法耗散与弥散特性、超调和自启动特性和多自由度系统计算步骤,最后通过数值算例验证了算法的收敛精度、可控数值阻尼和计算效率优势。研究结果表明:对于线性和非线性系统,该算法都兼具显式算法的非迭代特性和隐式算法的无条件稳定特性;该算法能实现真正意义上的自启动并且在速度和位移上均无超调;该算法的数值阻尼由单自由参数控制,数值耗散和弥散对系统低模态响应的影响可以忽略不计,与具有代表性的非迭代显式算法KR-α法相比,该算法在引入数值阻尼滤除虚假高频模态的同时更真实地保留了低阶振型的贡献,从而表现出更好的计算精度;该算法在求解非线性结构动力学问题时相较于常用隐式算法有着显著的计算效率优势,并略优于两求解器非迭代显式算法KR-α法。研究结果很有希望成为求解非线性结构动力学问题的最新且更加有效的显式算法。 展开更多
关键词 显式算法 非迭代算法 无条件稳定 可控数值阻尼 结构动力计算
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影响结核性胸腔积液并发胸膜增厚的非条件Logistic回归分析
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作者 梁小朋 胡锦兴 +2 位作者 韩建芳 蔡智群 吴碧彤 《当代医学》 2024年第3期103-106,共4页
目的探讨影响结核性胸腔积液并发胸膜增厚的相关危险因素。方法回顾性分析2019年1月至2021年3月广州市胸科医院呼吸内科收治的123例结核性胸腔积液患者的临床资料,统计患者胸膜增厚情况,采用单因素及非条件Logistic回归法分析患者胸膜... 目的探讨影响结核性胸腔积液并发胸膜增厚的相关危险因素。方法回顾性分析2019年1月至2021年3月广州市胸科医院呼吸内科收治的123例结核性胸腔积液患者的临床资料,统计患者胸膜增厚情况,采用单因素及非条件Logistic回归法分析患者胸膜增厚的影响因素。结果胸膜未增厚与胸膜增厚患者性别、年龄、肺结核、胸水分布、用力肺活量(FVC)、第1秒用力呼气容积(FVE1)/FVC、胸水腺苷脱氨酶(ADA)、血清ADA、胸水白细胞、胸水淋巴细胞、胸水中性粒细胞和淋巴细胞比例比较差异无统计学意义;胸膜未增厚与胸膜增厚患者胸水量、胸水吸收时间、FVE1、胸水乳酸脱氢酶(LDH)、血清LDH、胸水蛋白、血清蛋白比较差异有统计学意义(P<0.05)。Logistic回归分析结果显示,胸水量(中大量)、FVE1、胸水LDH、血清LDH、胸水蛋白及血清蛋白是胸膜增厚发生的危险因素(P<0.05)。结论结核性胸腔积液并发胸膜增厚是多因素作用的结果,胸水量、FVE1、胸水吸收时间、胸水LDH、血清LDH、胸水蛋白和血清蛋白与胸膜增厚的发生密切相关,建议临床予以密切监测并积极采取针对性干预措施。 展开更多
关键词 结核性胸腔积液 胸膜增厚 非条件LOGISTIC回归分析 危险因素
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公共教育扩张政策与教育收益率的城乡差异
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作者 方超 《复旦教育论坛》 北大核心 2024年第3期92-101,共10页
基于2019年中国家庭收入调查数据,通过教育收益率的因果性和异质性测量,实证评估了公共教育扩张政策的个体增收效应和收入分配效应。研究结果如下:(1)利用描述性统计法分析发现,公共教育扩张政策对城镇劳动力受教育程度的提升作用高于农... 基于2019年中国家庭收入调查数据,通过教育收益率的因果性和异质性测量,实证评估了公共教育扩张政策的个体增收效应和收入分配效应。研究结果如下:(1)利用描述性统计法分析发现,公共教育扩张政策对城镇劳动力受教育程度的提升作用高于农村,因而教育功能具有“城市偏向型”的特征;(2)利用工具变量法纠正内生性问题后,发现公共教育扩张政策对非农户籍具有更强的个体增收效应,农村劳动力的教育收益率高于城镇,大学教育收益率高于义务教育阶段,揭示了公共教育扩张政策的个体增收效应具有“农村导向型”的特征;(3)利用无条件分位数回归及其处理效应模型发现,义务教育改革和高校扩招具有缩小城乡劳动力组内工资收入差距的收入分配功能。 展开更多
关键词 公共教育扩张政策 教育收益率 城乡差异 收入分配效应 无条件处理效应模型
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Dynamics and genetic regulation of macronutrient concentrations during grain development in maize 被引量:1
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作者 Pengcheng Li Shuangyi Yin +7 位作者 Yunyun Wang Tianze Zhu Xinjie Zhu Minggang Ji Wenye Rui Houmiao Wang Chenwu Xu Zefeng Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期781-794,共14页
Nitrogen(N), phosphorus(P), and potassium(K) are essential macronutrients that are crucial not only for maize growth and development, but also for crop yield and quality. The genetic basis of macronutrient dynamics an... Nitrogen(N), phosphorus(P), and potassium(K) are essential macronutrients that are crucial not only for maize growth and development, but also for crop yield and quality. The genetic basis of macronutrient dynamics and accumulation during grain filling in maize remains largely unknown. In this study, we evaluated grain N, P, and K concentrations in 206 recombinant inbred lines generated from a cross of DH1M and T877 at six time points after pollination. We then calculated conditional phenotypic values at different time intervals to explore the dynamic characteristics of the N, P, and K concentrations. Abundant phenotypic variations were observed in the concentrations and net changes of these nutrients. Unconditional quantitative trait locus(QTL) mapping revealed 41 non-redundant QTLs, including 17, 16, and 14 for the N, P, and K concentrations, respectively. Conditional QTL mapping uncovered 39 non-redundant QTLs related to net changes in the N, P, and K concentrations. By combining QTL, gene expression, co-expression analysis, and comparative genomic data, we identified 44, 36, and 44 candidate genes for the N, P, and K concentrations, respectively, including GRMZM2G371058 encoding a Doftype zinc finger DNA-binding family protein, which was associated with the N concentration, and GRMZM2G113967encoding a CBL-interacting protein kinase, which was related to the K concentration. The results deepen our understanding of the genetic factors controlling N, P, and K accumulation during maize grain development and provide valuable genes for the genetic improvement of nutrient concentrations in maize. 展开更多
关键词 MAIZE nutrient concentration unconditional QTL mapping conditional QTL mapping dynamic trait
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基于量子纠缠测量理论的电子支付协议设计
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作者 朱旻昊 马雷 《华东师范大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期136-146,共11页
提出了一个基于量子力学基本理论的电子支付协议.经典支付系统存在部分漏洞,可能会带来安全隐患.利用纠缠粒子之间的关联性,实现签名、购买、支付等环节;使用量子单向函数和量子交换测试线路,验证签名的有效性;通过信道检测中的冗余粒... 提出了一个基于量子力学基本理论的电子支付协议.经典支付系统存在部分漏洞,可能会带来安全隐患.利用纠缠粒子之间的关联性,实现签名、购买、支付等环节;使用量子单向函数和量子交换测试线路,验证签名的有效性;通过信道检测中的冗余粒子传输支付信息,节约成本.该方案在量子力学基本原理的保证下,具有无条件的安全性,符合支付系统的基本要求. 展开更多
关键词 量子支付协议 量子纠缠 量子签名 无条件安全
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农业生产者绿色生产要素投入行为的收入效应 被引量:2
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作者 王建华 周瑾 任敏慧 《西北农林科技大学学报(社会科学版)》 北大核心 2024年第1期110-123,共14页
以有机肥和生物农药两类绿色投入品为例,运用内生转换回归模型,实证分析农业生产者绿色生产要素投入行为的收入效应,并运用无条件分位数回归进行异质性分析。研究表明:(1)绿色生产要素投入行为受到内外部因素的影响,不同绿色生产要素的... 以有机肥和生物农药两类绿色投入品为例,运用内生转换回归模型,实证分析农业生产者绿色生产要素投入行为的收入效应,并运用无条件分位数回归进行异质性分析。研究表明:(1)绿色生产要素投入行为受到内外部因素的影响,不同绿色生产要素的投入行为影响因素有所差异;(2)不同绿色生产要素投入决策条件下农业收入的影响因素有较大差异,新型农业经营类型能够显著提高农业收入;(3)绿色生产要素投入行为具有正向收入效应;(4)有机肥投入随着农业收入的提升,影响程度有逐渐递减趋势,生物农药投入对农业收入的影响程度呈现“倒U”型特征,不同主体类型和地理区域对不同农业收入水平的影响程度存在显著差异。 展开更多
关键词 绿色生产要素 收入效应 新型农业经营主体 内生转换回归模型 无条件分位数回归
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气候适应性技术采纳对农户农业收入的影响
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作者 李现康 韩星星 梁洪松 《气候变化研究进展》 CSCD 北大核心 2024年第2期193-204,共12页
为探究气候变化冲击下,气候适应性技术采纳对农户农业收入的影响效应,文中基于黄河流域中上游地区6个省份2502份农户调研数据,使用无条件分位数回归(UQR)和再中心化影响函数(RIF)分解回归,分析了气候适应性技术采纳对不同农业收入水平... 为探究气候变化冲击下,气候适应性技术采纳对农户农业收入的影响效应,文中基于黄河流域中上游地区6个省份2502份农户调研数据,使用无条件分位数回归(UQR)和再中心化影响函数(RIF)分解回归,分析了气候适应性技术采纳对不同农业收入水平农户的增收效应及收入差距影响机制,得出以下结论:气候适应性技术采纳对农业收入水平由低到高的农户的增收效应不断递减,对低农业收入水平农户增收效应最明显;气候适应性技术采纳可以缩减农户内部农业收入差距,对低农业收入水平组影响效应最明显;RIF分解回归显示,结构效应是农户内部农业收入差距缩小的主因,以农户受教育水平影响最主要。因此,气候适应性技术应该被广泛推广,同时要注意提升农户对气候适应性技术的理解与认知,提高农户对气候适应性技术的接受意愿,鼓励农业收入低水平农户采取组合型气候适应性技术,同时政府可根据实际情况给予农户适当使用补贴,减轻农户使用负担。 展开更多
关键词 气候适应性技术 农业收入 不同收入水平 无条件分位数回归(UQR) 再中心化影响函数(RIF)分解回归
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UNCONDITIONAL CONVERGENCE AND ERROR ESTIMATES OF A FULLY DISCRETE FINITE ELEMENT METHOD FOR THE MICROPOLAR NAVIER-STOKES EQUATIONS
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作者 Shipeng Mao Jiaao Sun Wendong Xue 《Journal of Computational Mathematics》 SCIE CSCD 2024年第1期71-110,共40页
In this paper,we consider the initial-boundary value problem(IBVP)for the micropolar Naviers-Stokes equations(MNSE)and analyze a first order fully discrete mixed finite element scheme.We first establish some regularit... In this paper,we consider the initial-boundary value problem(IBVP)for the micropolar Naviers-Stokes equations(MNSE)and analyze a first order fully discrete mixed finite element scheme.We first establish some regularity results for the solution of MNSE,which seem to be not available in the literature.Next,we study a semi-implicit time-discrete scheme for the MNSE and prove L2-H1 error estimates for the time discrete solution.Furthermore,certain regularity results for the time discrete solution are establishes rigorously.Based on these regularity results,we prove the unconditional L2-H1 error estimates for the finite element solution of MNSE.Finally,some numerical examples are carried out to demonstrate both accuracy and efficiency of the fully discrete finite element scheme. 展开更多
关键词 Micropolar fluids Regularity estimates Euler semi-implicit scheme Mixed finite element methods unconditional convergence
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修正相场晶体(MPFC)模型的二阶无条件能量稳定数值格式
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作者 郝婉蓉 贾宏恩 《应用数学》 北大核心 2024年第1期124-132,共9页
本文研究修正的相场晶体(MPFC)方程的二阶无条件能量稳定数值格式.首先,利用标量辅助变量(SAV)法和二阶向后欧拉(BDF2)公式,得到了一个数值格式;其次,给出了能量耗散定律,严格证明了该数值格式是质量守恒的,唯一可解的,无条件能量稳定的... 本文研究修正的相场晶体(MPFC)方程的二阶无条件能量稳定数值格式.首先,利用标量辅助变量(SAV)法和二阶向后欧拉(BDF2)公式,得到了一个数值格式;其次,给出了能量耗散定律,严格证明了该数值格式是质量守恒的,唯一可解的,无条件能量稳定的;最后,通过数值实例验证了格式的精度和稳定性. 展开更多
关键词 标量辅助变量 无条件能量稳定 BDF2 修正相场晶体方程
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