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Lagrange方程 1

云模型 1

倒排索引；索引遍历；查询延迟；最大重要度优先查询；动态剪枝 1

倒立摆 1

定性推理 1

旋转倒立摆 1

智能控制 1

最优控制策略LQR 1

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Finite element analysis and structural design of pretensioned inverted T-beams with web openings

Hock Tian CHENG, Bashar S. MOHAMMED, Kamal Nasharuddin MUSTAPHA

《结构与土木工程前沿（英文）》 2009年第3卷第2期页码 148-157 doi: 10.1007/s11709-009-0030-5

摘要： This paper presents the results of a research project aimed at providing standard circular web openings to the popular precast pretensioned inverted T-beam. Opening size and placement and required materials strengths were investigated. In this paper the nonlinear analysis and design of simply supported pretensioned inverted T-beam with circular web openings are presented. Two design parameters are varied: opening location and number of openings. The results from nonlinear finite element analysis were substantiated by test results from five pretensioned inverted T-beams with web opening and one solid beam. Good agreement is shown between the theoretical and the experimental results. The test results obtained from this investigation show that the performance of the specimens with web openings is almost identical to that of the specimen without web openings. A simple design method for pretensioned inverted T-beam with circular web openings is proposed.

关键词： prestressed concrete inverted-T beam web opening

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Ultimate load analysis of pretensioned inverted T-beams with circular web openings

Hock Tian CHENG , Bashar S. MOHAMMED , Kamal Nasharuddin MUSTAPHA ,

《结构与土木工程前沿（英文）》 2009年第3卷第3期页码 262-271 doi: 10.1007/s11709-009-0031-4

摘要： The provision of transverse openings in floor beams to facilitate the passage of utility pipes and service ducts not only results in a more systematic layout of pipes and ducts, it also translates into substantial economic savings in the construction of a multi-storey building. In this paper, ultimate load analysis of statically loaded simply supported pretensioned inverted T-beams with circular web openings is presented. Major findings relevant to ultimate load analysis of pretensioned beams with circular web openings are summarized. An attempt has been made to answer the frequently asked questions related to ultimate load analysis on multiple circular web openings. It has been shown that the analysis method for pretensioned beams with multiple large circular web openings can be further simplified without sacrificing rationality.

关键词： pretensioned inverted T-beam web opening

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Inverted duplication including

Ming TIAN,Suyun FANG,Yanqiang WANG,Xiaorong GU,Chungang FENG,Rui HAO,Xiaoxiang HU,Ning LI

《农业科学与工程前沿（英文）》 2014年第1卷第2期页码 121-129 doi: 10.15302/J-FASE-2014026

摘要： The dermal hyperpigmentation phenotype in chickens is controlled by the dominant fibromelanosis allele. One of the ten unique characteristics of Silkie chickens is the fibromelanosis phenotype, which is pigmentation in the dermal layer of the skin and connective tissue. In this study, we found a mutation of fibromelanosis, a genomic rearrangement that included an inverted duplication of ( ), is responsible. We show that, as a stimulator of melanoblast proliferation, expression was increased in silkie embryos and in both skin and muscle throughout adulthood. expression led to an increase in expression of the downstream genes and and was closely relate with the hyperpigmentation phenotype. We examined eight different Chinese chicken breeds showing hyperpigmentation and conclude that this structural genetic variant exists in all fibromelanosis chicken breeds.

关键词： dermal hyperpigmentation duplication endothelin 3 Silkie chicken

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Is there an inverted U-shaped curve?

Fei LI,Suocheng DONG,Fujia LI,Libiao YANG

《环境科学与工程前沿（英文）》 2016年第10卷第2期页码 276-287 doi: 10.1007/s11783-014-0700-y

摘要： As the largest contributor to water impairment, agriculture-related pollution has attracted the attention of scientists as well as policy makers, and quantitative information is being sought to focus and advance the policy debate. This study applies the panel unit root, heterogeneous panel cointegration, and panel-based dynamic ordinary least squares to investigate the Environmental Kuznets Curve on environmental issues resulting from use of agricultural synthetic fertilizer, pesticide, and film for 31 provincial economies in mainland China from 1989 to 2009. The empirical results indicate a positive long-run co-integrated relationship between the environmental index and real GDP per capita. This relationship takes on the inverted U-shaped Environmental Kuznets Curve, and the value of the turning point is approximately 10,000–13,000, 85,000–89,000 and over 160,000 CNY, for synthetic fertilizer nitrogen indicator, fertilizer phosphorus indicator and pesticide indicator, respectively. At present, China is subject to tremendous environmental pressure and should assign more importance to special agriculture-related environmental issues.

关键词： Environmental Kuznets Curve agrochemical China

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三级倒立摆的云控制方法及动平衡模式

李德毅

《中国工程科学》 1999年第1卷第2期页码 41-46

摘要：

文章提出了定性和定量之间转换的云模型的形式化表示方法，用来反映语言值中蕴涵的模糊性和随机性，给出云发生器的生成算法，解释多条定性推理规则同时被激活时的不确定性推理机制。利用这种智能控制方法有效地实现了单电机控制的一、二、三级倒立摆的多种不同动平衡姿态，显示其鲁棒性，并给出了详细试验结果。研究成果不仅可用于对太空飞行器以及机器人控制，而且对揭示定性定量转换规律和策略具有普遍意义。

关键词：智能控制云模型定性推理倒立摆

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基于Lagrange方程建模的单级旋转倒立摆控制

吴爱国,张小明,张钊

《中国工程科学》 2005年第7卷第10期页码 11-15

摘要：

介绍一种新型单级旋转倒立摆系统的构成，通过对其动力学特性的分析建立了基于Lagrange方程的数学模型。在平衡点附近给出系统的线性化模型，对系统的稳定性、能控性和能观性进行了分析。利用线性二次型最优控制策略LQR方法设计了控制器，并在仿真实验和实物实验中实现了倒立摆的平衡控制。实验表明，系统稳定性好、鲁棒性较强。

关键词：旋转倒立摆 Lagrange方程最优控制策略LQR

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Dynamic visco-plastic memorial nested yield surface model of soil

ZHUANG Haiyang, CHEN Guoxing, ZHU Dinghua

《结构与土木工程前沿（英文）》 2008年第2卷第1期页码 49-55 doi: 10.1007/s11709-008-0003-0

摘要： Under cyclic loadings, the plastic strain of soft soil will take place under very small shear strain. So the visco-plastic model is appropriate to be used to model the dynamic characteristics of soft soil. Based on the principles of geotechnical plastic mechanics, the incremental visco-plastic memorial nested yield surface model is developed by using the field theory of nonlinear isotropic materials and the theory of kinematical hardening modulus. At the end of anyone time increment, the inverted loading surface, the damaged surface and the initial loading surface which is tangent with the inside of inverted loading surface are memorized respectively. The kinematical behavior of yield surface is defined by using these three surfaces. The developed model in this paper is successfully implemented in ABAQUS using FORTRAN subroutine. The predicted stress-strain relationships of soft soil are compared with the test results given by dynamic triaxial tests. It is proved that the cyclic undrained stress-strain relation of soils can be fairly simulated by the model. At last, the nonlinear earthquake response of a representative soft site in Nanjing city is calculated with the dynamic behavior of soils modeled by the new developed model. The results are accordant to the earthquake response of soft site given by other scholars.

关键词： developed dynamic surface inverted appropriate

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基于最大重要度优先查询的动态剪枝算法

Kun JIANG,Yue-xiang YANG

《信息与电子工程前沿（英文）》 2016年第17卷第1期页码 1-14 doi: 10.1631/FITEE.1500190

摘要：

已经研究了反向索引遍历技术来解决Web搜索引擎的查询处理性能挑战，但是仍然有很多改进的余地。在本文中，我们将重点放在文档排序索引的倒排索引遍历和称为动态修剪的优化技术上，该技术可以有效地减少所需的硬件计算资源。我们提出了另一种新颖的穷举索引遍历方案，称为最大分数优先（LSF）检索，其中首先在具有最大上限分数的重要查询词的发布列表中选择候选者，然后对其余查询词的贡献进行全面评分。该方案可以有效地减少现有的一次性词汇（TAAT）的内存消耗和现有的一次性文档（DAAT）检索的候选选择成本，但以重新访问其余查询词语的发布列表为代价。初步分析和实施表明，LSF和两个众所周知的基准之间的性能相当。为了进一步减少需要重新审查的发布数量，我们提出了基于LSF的有效的排名安全动态修剪技术，包括两个重要的优化方法，分别称为列表省略（LSF_LO）和部分计分（LSF_PS），它们充分利用了查询字词的重要性。最终，TREC GOV2集合的实验结果表明，我们的新索引遍历方法在WAND基线上将查询延迟减少了近27％，并且与MaxScore基线相比，产生了更好的结果，而返回的结果与详尽评估相同。 >

关键词：倒排索引；索引遍历；查询延迟；最大重要度优先查询；动态剪枝

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Sagittal SLIP-anchored task space control for a monopode robot traversing irregular terrain

Haitao YU, Haibo GAO, Liang DING, Zongquan DENG

《机械工程前沿（英文）》 2020年第15卷第2期页码 193-208 doi: 10.1007/s11465-019-0569-3

摘要： As a well-explored template that captures the essential dynamical behaviors of legged locomotion on sagittal plane, the spring-loaded inverted pendulum (SLIP) model has been extensively employed in both biomechanical study and robotics research. Aiming at fully leveraging the merits of the SLIP model to generate the adaptive trajectories of the center of mass (CoM) with maneuverability, this study presents a novel two-layered sagittal SLIP-anchored (SSA) task space control for a monopode robot to deal with terrain irregularity. This work begins with an analytical investigation of sagittal SLIP dynamics by deriving an approximate solution with satisfactory apex prediction accuracy, and a two-layered SSA task space controller is subsequently developed for the monopode robot. The higher layer employs an analytical approximate representation of the sagittal SLIP model to form a deadbeat controller, which generates an adaptive reference trajectory for the CoM. The lower layer enforces the monopode robot to reproduce a generated CoM movement by using a task space controller to transfer the reference CoM commands into joint torques of the multi-degree of freedom monopode robot. Consequently, an adaptive hopping behavior is exhibited by the robot when traversing irregular terrain. Simulation results have demonstrated the effectiveness of the proposed method.

关键词： legged robots spring-loaded inverted pendulum task space control apex return map deadbeat control irregular terrain negotiation