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期刊论文 29

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干旱 2

章动 2

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Tempotron；神经元模型；感受野；高斯差分；图像翻转；图像旋转 1

光镊；光致旋转；角动量；微纳转子 1

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哈密尔顿图 1

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循环移位操作；自路由；控制信息生成算法；Inverse butterfly网络 1

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搅拌头旋转速度 1

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Sufficient downward rotation of the christa philtri on the cleft side: a modified technique

null

《医学前沿（英文）》 2013年 第7卷 第4期   页码 510-516 doi: 10.1007/s11684-013-0299-6

摘要：

Cleft lip and palate (CLP) is the most common craniofacial congenital deformity. The etiology of CLP is multifactorial and involves complex interactions between environmental and genetic factors. Millard’s rotation-advancement technique has long been considered as state-of-the-art for unilateral cleft lip repair. However, this method may leave the christa philtri on the cleft side insufficiently downward rotated, especially in wide complete clefts. In this study, we introduce a modified technique to better rotate the christa philtri on the cleft side down. The skin, muscle, and mucosa in the deformed region were dissected and separately maneuvered. Sixty patients with unilateral complete cleft lip and palate were operated with this technique. The lip height, lip length, and relative height of the christa philtri were measured for symmetry evaluation. No significant difference was observed between the relative height of the christa philtri on both sides, either immediate (P= 0.214) or 10 months after surgery (P = 0.344). The difference observed in the lip height and lip length immediately after surgery became statistically insignificant after 10 months (P = 0.104 for lip height and 0.121 for lip length). These results suggested that sufficient and stable downward rotation of the christa philtri on the cleft side can be achieved using our technique.

关键词： cleft lip and palate     rotation advancement     sufficient rotation     christa philtri geometrically justified    

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Effect of RC wall on the development of plastic rotation in the beams of RC frame structures

Amar KAHIL, Aghiles NEKMOUCHE, Said BOUKAIS, Mohand HAMIZI, Naceur Eddine HANNACHI

《结构与土木工程前沿（英文）》 2018年 第12卷 第3期   页码 318-330 doi: 10.1007/s11709-017-0420-z

摘要：

The objective of this study is, to interpret the influence of reinforced concrete walls addition in reinforced concrete frame structures considering behavior laws that reflects the actual behavior of such structures, by means of Castem2000computer code (pushover analysis). A finite element model is proposed in this study, using the TAKEDA modified behavior model with Timoshenko beams elements. This model is validated initially on experimental model. Then the work has focused on the behavior of a RC frame with 3 levels and three bays to better visualize the behavior of plastic hinges. Once the plastic hinge control parameters are identified (plastic rotation, ultimate curvature), a strengthening by introduction of reinforced concrete walls (RC/wall) at the ends of the reinforced concrete frame (RC/frame) has been performed. The results show that these RC walls significantly improve the behavior, by a relocation of efforts towards the central part of the beams.

关键词： RC/frame     RC/wall     moment curvature     plastic rotation     plastic hinge     pushover analysis     global models    

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Parasitic rotation evaluation and avoidance of 3-UPU parallel mechanism

Haibo QU, Yuefa FANG, Sheng GUO

《机械工程前沿（英文）》 2012年 第7卷 第2期   页码 210-218 doi: 10.1007/s11465-012-0317-4

摘要：

Based on the prototype of 3-UPU (universal-prismatic-universal joint) parallel mechanism proposed by Tsai [ ], the parasitic rotation evaluation is performed and calculated the bound of instability of SNU Seoul National University 3-UPU parallel mechanism. Through analysis of the terminal constraint system of the 3-UPU parallel mechanism, the equation about the parasitic rotation and limited clearance is presented. Then the norm of possible parasitic rotation is employed to evaluate the mechanism stability with limited clearance. The higher this number the worst is the pose, the lower it is the best it is. And the contour atlas of parasitic rotation is obtained, which can be used for further analysis and design. With the practice experiment result of SUN 3-UPU parallel mechanism, we find it’s bound of instability, which indicates there will appear the parasitic rotation when the number exceeds the bound. Finally, the method for avoidance of possible parasitic motions is presented by adding redundantly actuated limbs.

关键词： parallel mechanism     3-UPU (universal-prismatic-universal joint)     parasitic motions     limited clearance     redundantly actuated limbs    

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Rotation errors in numerical manifold method and a correction based on large deformation theory

Ning ZHANG, Xu LI, Qinghui JIANG, Xingchao LIN

《结构与土木工程前沿（英文）》 2019年 第13卷 第5期   页码 1036-1053 doi: 10.1007/s11709-019-0535-5

摘要： Numerical manifold method (NMM) is an effective method for simulating block system, however, significant errors are found in its simulation of rotation problems. Three kinds of errors, as volume expansion, stress vibration, and attenuation of angular velocity, were observed in the original NMM. The first two kind errors are owing to the small deformation assumption and the last one is due to the numerical damping. A large deformation NMM is proposed based on large deformation theory. In this method, the governing equation is derived using Green strain, the large deformation iteration and the open-close iteration are combined, and an updating strategy is proposed. The proposed method is used to analyze block rotation, beam bending, and rock falling problems and the results prove that all three kinds of errors are eliminated in this method.

关键词： numerical manifold method     rotation     large deformation     Green strain     open-close iteration    

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地球的章动和转速与副热带高压和高温干旱

魏鸣,欧阳首承

《中国工程科学》 2007年 第9卷 第8期   页码 40-46

摘要：

鉴于近10多年来运用地球转速的变化做长期灾害天气预测取得的较好效果，试图运用地球的章动、地球转速和大气变化的关系，探索 重大灾害天气的深层次原因。仅就2006年发生在四川、重庆的高温干旱问题，讨论了副热带高压与东风层的关系，进而对地球的章动、转速的变化做了对比分析。结果显示，地球大气的重要灾害天气的发生，不只限于大气本身的原因，而确有可用于天气预测的星体运行的变化信息。

关键词： 章动     地球转速     副热带高压     逆滚流下沉     干旱    

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SUSTAINABLE SUGARCANE CROPPING IN CHINA

《农业科学与工程前沿（英文）》 2022年 第9卷 第2期   页码 272-283 doi: 10.15302/J-FASE-2022442

摘要：

Demand for sugar is projected to grow in China for the foreseeable future. However, sugarcane production is unlikely to increase due to increasing production cost and decreasing profit margin. The persisting sugarcane yield plateau and the current cropping system with fertilizer overuse, soil acidification and pests and diseases remain the major productivity constraints. Sugarcane agriculture supports the livelihood of about 28 million farmers in South China; hence, sustaining it is a socioeconomic imperative. More compellingly, to meet the ever-increasing Chinese market demand, annual sugar production must be increased from the current 10 Mt to 16 Mt by 2030 of which 80% to 90% comes from sugarcane. Therefore, increasing sugar yield and crop productivity in an environmentally sustainable way must be a priority. This review examines the current Chinese sugarcane production system and discuss options for its transition to a green, sustainable cropping system, which is vital for the long-term viability of the industry. This analysis shows that reducing chemical inputs, preventing soil degradation, improving soil health, managing water deficit, provision of clean planting material, and consolidation of small farm holdings are critical requirements to transform the current farming practices into an economically and environmentally sustainable sugarcane cropping system.

关键词： sustainable sugarcane cropping / soil health / rotation and intercropping / soil acidification    

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Development and clinical trial of a novel bioactive bone cement

LEONG John, LI Zhaoyang, LU William

《医学前沿（英文）》 2008年 第2卷 第2期   页码 117-126 doi: 10.1007/s11684-008-0022-1

摘要： Strontium (Sr) and related compounds have become more attractive in the prevention and treatment of osteoporosis. Previously, we developed a novel bioactive bone cement which is mainly composed of strontium-containing hydroxyapatite (Sr-HA) filler and bisphenol A diglycidylether dimethacrylate (Bis-GMA) resin. This bone cement is superior to conventional polymethylmethacrylate (PMMA) bone cement in bioactivity, biocompatibility, and osseointegration. It also has shown sufficient mechanical strength properties for its use in percutaneous vertebroplasty (PVP) and total hip replacement (THR). In this paper, we review the and clinical evidence for the effectiveness of this bioactive bone cement.

关键词： bioactivity     effectiveness     strontium-containing hydroxyapatite     osseointegration     sufficient mechanical    

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An innovative model for predicting the displacement and rotation of column-tree moment connection under

Mohammad Ali NAGHSH, Aydin SHISHEGARAN, Behnam KARAMI, Timon RABCZUK, Arshia SHISHEGARAN, Hamed TAGHAVIZADEH, Mehdi MORADI

《结构与土木工程前沿（英文）》 2021年 第15卷 第1期   页码 194-212 doi: 10.1007/s11709-020-0688-2

摘要： In this study, we carried out nonlinear finite element simulations to predict the performance of a column-tree moment connection (CTMC) under fire and static loads. We also conducted a detailed parameter study based on five input variables, including the applied temperature, number of flange bolts, number of web bolts, length of the beam, and applied static loads. The first variable is changed among seven levels, whereas the other variables are changed among three levels. Employing the Taguchi method for variables 2–5 and their levels, 9 samples were designed for the parameter study, where each sample was exposed to 7 different temperatures yielding 63 outputs. The related variables for each output are imported for the training and testing of different surrogate models. These surrogate models include a multiple linear regression (MLR), multiple Ln equation regression (MLnER), an adaptive network-based fuzzy inference system (ANFIS), and gene expression programming (GEP). 44 samples were used for training randomly while the remaining samples were employed for testing. We show that GEP outperforms MLR, MLnER, and ANFIS. The results indicate that the rotation and deflection of the CTMC depend on the temperature. In addition, the fire resistance increases with a decrease in the beam length; thus, a shorter beam can increase the fire resistance of the building. The numbers of flanges and web bolts slightly affect the rotation and displacement of the CTMCs at temperatures of above 400°C.

关键词： column-tree moment connection     Finite element model     parametric study     fire     regression models     gene expression programming    

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Process evaluation of an alternating aerobic-anoxic process applied in a sequencing batch reactor for nitrogen removal

ZENG Wei, PENG Yongzhen, WANG Shuying

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 28-32 doi: 10.1007/s11783-007-0005-5

摘要： In order to improve the nitrogen removal efficiency and save operational cost, the feasibility of the alternating aerobic-anoxic process (AAA process) applied in a sequencing batch reactor (SBR) system for nitrogen removal was investigated. Under sufficient influent alkalinity, the AAA process did not have an advantage over one aerobicanoxic (OAA) cycle on treatment efficiency because microorganisms had an adaptive stage at the alternating aerobic-anoxic transition, which would prolong the total cycling time. On the contrary, the AAA process made the system control more complicated. Under deficient influent alkalinity, when compared to OAA, the AAA process improved treatment efficiency and effluent quality with NH-N in the effluent below the detection limit. In the nitrification, the average stoichiometric ratio between alkalinity consumption and ammonia oxidation is calculated to be 7.07 mg CaCO/mg NH-N. In the denitrification, the average stoichiometric ratio between alkalinity production and NO-N reduction is about 3.57 mg CaCO/mg NO-N. As a result, half of the alkalinity previously consumed during the aerobic nitrification was recovered during the subsequent anoxic denitrification period. That was why the higher treatment efficiency in the AAA process was achieved without the supplement of bicarbonate alkalinity. If the lack of alkalinity in the influent was less than 1/3 of that needed, there is no need for external alkalinity addition and treatment efficiency was the same as that under sufficient influent alkalinity. Even if the lack of alkalinity in the influent was more than 1/3 of that needed, the AAA process was an optimal strategy because it reduced the external alkalinity addition and saved on operational cost.

关键词： bicarbonate alkalinity     sufficient influent     influent alkalinity     detection     alkalinity production    

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光致旋转技术综述 Review Article

朱琦1,李楠1,苏鹤鸣1,李文强1,胡慧珠1,2

《信息与电子工程前沿（英文）》 2022年 第23卷 第2期   页码 171-185 doi: 10.1631/FITEE.2000338

摘要： 光致旋转技术兴起于20世纪90年代。光镊为研究激光角动量提供了一个理想平台。近几十年来，光致旋转技术被广泛运用在光学微操控实验和生物与微流控领域。近年来，其在经典和量子物理领域的应用潜力引起人们广泛关注。本文回顾了光致旋转技术实验与应用进展。首先介绍了角动量的基本研究。其次，介绍了由轨道角动量引起的光致旋转技术的发展和应用，并给出自旋角动量的概念。最后，介绍了光致旋转技术在高真空光阱中的应用与前景。随着液体介质中精密光学操作技术的成熟，高真空光镊技术为高速微纳转子开辟了一条新道路。

关键词： 光镊；光致旋转；角动量；微纳转子    

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TRADE-OFFS IN THE DESIGN OF SUSTAINABLE CROPPING SYSTEMS AT A REGIONAL LEVEL: A CASE STUDY ON THE NORTH CHINA PLAIN

《农业科学与工程前沿（英文）》 2022年 第9卷 第2期   页码 295-308 doi: 10.15302/J-FASE-2021434

摘要：

Since the Green Revolution cropping systems have been progressively homogenized and intensified with increasing rates of inputs such as fertilizers, pesticides and water. This has resulted in higher crop productivity but also a high environmental burden due to increased pollution and water depletion. To identify opportunities for increasing the productivity and reducing the environmental impact of cropping systems, it is crucial to assess the associated trade-offs. The paper presents a model-based analysis of how 30 different crop rotations practiced in the North China Plain could be combined at the regional level to overcome trade-offs between indicators of economic, food security, and environmental performance. The model uses evolutionary multi-objective optimization to maximize revenues, livestock products, dietary and vitamin C yield, and to minimize the decline of the groundwater table. The modeling revealed substantial trade-offs between objectives of maximizing productivity and profitability versus minimizing ground water decline, and between production of livestock products and vitamin C yield. Six strategies each defining a specific combination of cropping systems and contributing to different extents to the various objectives were identified. Implementation of these six strategies could be used to find opportunities to mitigate the trade-offs between objectives. It was concluded that a holistic analysis of the potential of a diversity cropping systems at a regional level is needed to find integrative solutions for challenges due to conflicting objectives for food production, economic viability and environmental protection.

关键词： crop rotation / food security / multi-objective optimization / water use    

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生物细胞的旋转——基本原理及应用 Review

Tao Tang, Yoichiroh Hosokawa, Takeshi Hayakawa, Yo Tanaka, Weihua Li, Ming Li, Yaxiaer Yalikun

《工程（英文）》 2022年 第10卷 第3期   页码 110-126 doi: 10.1016/j.eng.2020.07.031

摘要：

细胞旋转是现代生物科学中最重要的细胞操作技术之一，不仅允许从任意角度观察细胞，而且还简化了分析细胞力学特性、表征细胞生理学和进行显微手术的程序。在广泛的学术和工业应用中，已经报道了许多细胞旋转的方法。其中，最受欢迎的是基于微型机器人的直接接触控制和基于场的非接触方法（如光场、磁场、电场、声场和流体动力场方法）。本文首先总结了这六大类方法的基本机制、优点和缺点，然后详细讨论了它们的区别和局限性。本文旨在缩短每种方法之间的差距，并说明细胞旋转领域目前的研究进展及未来前景。

关键词： 细胞旋转     细胞重新定向     显微操作     微流控技术    

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新的充分条件和哈密尔顿图

赵克文

《中国工程科学》 2003年 第5卷 第11期   页码 61-64

摘要：

记δ和α分别表示图G的最小度和独立数，1991年Faudree等人得到图G不相邻的任意2点x,y均有|N(x)∪N(y)|≥n-δ的Hamiltonian结果。1993年美国乔治亚州立大学的陈冠涛教授深化Fan条件并且得到满足1≤|N (x)∩N(y)|≤α-1的不相邻的任2点x，y均有max{d(x),d(y)}≥n/2的Hamiltonian结果。进一步改进Faudree等人的条件和综合陈冠涛教授的思路,研究满足1≤|N(x)∩N(y)|≤α-1的不相邻的任2点x,y均有|N(x)∪N(y)|≥n-δ-1，则是哈密尔顿图或G∈{K(n-1)/2, (n + 1)/2, K2* V3K(n-2)/3}。

关键词： 哈密尔顿图     邻域并     最小度     独立数    

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基于Inverse Butterlfy网络的高效可重构循环移位单元 Article

Chao MA, Zi-bin DAI, Wei LI, Hai-juan ZANG

《信息与电子工程前沿（英文）》 2017年 第18卷 第11期   页码 1784-1794 doi: 10.1631/FITEE.1601265

摘要： 本文提出了一种利用inverse butterfly网络的自路由特性完成循环移位、短字循环移位等操作的可重构控制信息生成算法。该算法具有高并行度和低成本，此外还支持循环移位、双向循环移位以及短字循环移位操作。据我们所知，这是首个将多种不同类型的循环移位操作统一在一个硬件架构中的算法。本文进一步设计了一种高效可重构循环移位单元，并在SMIC 65-nm工艺下实现了逻辑综合。结果表明：与以往具有相似功能的设计相比，该单元的效能至少提升了23%；当仅支持双向循环移位操作时，该单元具有更小的面积和更低的延迟。

关键词： 循环移位操作；自路由；控制信息生成算法；Inverse butterfly网络    

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ENABLING CROP DIVERSIFICATION TO SUPPORT TRANSITIONS TOWARD MORE SUSTAINABLE EUROPEAN AGRIFOOD SYSTEMS

《农业科学与工程前沿（英文）》 2021年 第8卷 第3期   页码 474-480 doi: 10.15302/J-FASE-2021406

摘要：

European cropping systems are often characterized by short rotations or even monocropping, leading to environmental issues such as soil degradation, water eutrophication, and air pollution including greenhouse gas emissions, that contribute to climate change and biodiversity loss. The use of diversification practices (i.e., intercropping, multiple cropping including cover cropping and rotation extension), may help enhance agrobiodiversity and deliver ecosystem services while developing new value chains. Despite its benefits, crop diversification is hindered by various technical, organizational, and institutional barriers along value chains (input industries, farms, trading and processing industries, retailers, and consumers) and within sociotechnical systems (policy, research, education, regulation and advisory). Six EU-funded research projects have joined forces to boost crop diversification by creating the European Crop Diversification Cluster (CDC). This Cluster aggregates research, innovation, commercial and citizen-focused partnerships to identify and remove barriers across the agrifood system and thus enables the uptake of diversification measures by all European value-chain stakeholders. The CDC will produce a typology of barriers, develop tools to accompany actors in their transition, harmonize the use of multicriteria assessment indicators, prepare policy recommendations and pave the way for a long-term network on crop diversification.

 

关键词： crop rotation     lock-in     intercropping     multiple cropping     networking    

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标题 作者 时间 类型 操作

Sufficient downward rotation of the christa philtri on the cleft side: a modified technique

null

期刊论文

Effect of RC wall on the development of plastic rotation in the beams of RC frame structures

Amar KAHIL, Aghiles NEKMOUCHE, Said BOUKAIS, Mohand HAMIZI, Naceur Eddine HANNACHI

期刊论文

Parasitic rotation evaluation and avoidance of 3-UPU parallel mechanism

Haibo QU, Yuefa FANG, Sheng GUO

期刊论文

Rotation errors in numerical manifold method and a correction based on large deformation theory

Ning ZHANG, Xu LI, Qinghui JIANG, Xingchao LIN

期刊论文

地球的章动和转速与副热带高压和高温干旱

魏鸣,欧阳首承

期刊论文

SUSTAINABLE SUGARCANE CROPPING IN CHINA

期刊论文

Development and clinical trial of a novel bioactive bone cement

LEONG John, LI Zhaoyang, LU William

期刊论文

An innovative model for predicting the displacement and rotation of column-tree moment connection under

Mohammad Ali NAGHSH, Aydin SHISHEGARAN, Behnam KARAMI, Timon RABCZUK, Arshia SHISHEGARAN, Hamed TAGHAVIZADEH, Mehdi MORADI

期刊论文

Process evaluation of an alternating aerobic-anoxic process applied in a sequencing batch reactor for nitrogen removal

ZENG Wei, PENG Yongzhen, WANG Shuying

期刊论文

光致旋转技术综述

朱琦1,李楠1,苏鹤鸣1,李文强1,胡慧珠1,2

期刊论文

TRADE-OFFS IN THE DESIGN OF SUSTAINABLE CROPPING SYSTEMS AT A REGIONAL LEVEL: A CASE STUDY ON THE NORTH CHINA PLAIN

期刊论文

生物细胞的旋转——基本原理及应用

Tao Tang, Yoichiroh Hosokawa, Takeshi Hayakawa, Yo Tanaka, Weihua Li, Ming Li, Yaxiaer Yalikun

期刊论文

新的充分条件和哈密尔顿图

赵克文

期刊论文

基于Inverse Butterlfy网络的高效可重构循环移位单元

Chao MA, Zi-bin DAI, Wei LI, Hai-juan ZANG

期刊论文

ENABLING CROP DIVERSIFICATION TO SUPPORT TRANSITIONS TOWARD MORE SUSTAINABLE EUROPEAN AGRIFOOD SYSTEMS

期刊论文