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Chinese Journal of Polymer Science 2018年第4期36卷 488-496页

作者： Jun-Qing song Yi-Xin Liu Hong-Dong Zhang State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Science Fudan University

Self-consistent field theory（SCFT）, as a state-of-the-art technique for studying the self-assembly of block copolymers, is attracting continuous efforts to improve its accuracy and efficiency. Here we present a fourth-order exponential time differencing Runge-Kutta algorithm（ETDRK4） to solve the modified diffusion equation（MDE） which is the most time-consuming part of a SCFT calculation. By making a careful comparison with currently most efficient and popular algorithms, we demonstrate that the ETDRK4 algorithm significantly reduces the number of chain contour steps in solving the MDE, resulting in a boost of the overall computation efficiency, while it shares the same spatial accuracy with other algorithms. In addition, to demonstrate the power of our ETDRK4 algorithm, we apply it to compute the phase boundaries of the bicontinuous gyroid phase in the strong segregation regime and to verify the existence of the triple point of the O70 phase, the lamellar phase and the cylindrical phase.

关键词： Block copolymer Self-consistent field theory Algorithm Pseudo-spectral Phase structure

Effectiveness of a Passive-active Vibration Isolation System with Actuator Constraints

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 567-574页

作者： SUN Lingling SUN Wei song Kongjie HANSEN Colin H Key Laboratory of High-efficiency and Clean Mechanical Manufacture Shandong University School of Mechanical Engineering University of Adelaide

In the prediction of active vibration isolation performance, control force requirements were ignored in previous work. This may limit the realization of theoretically predicted isolation performance if control force of large magnitude cannot be supplied by *** behavior of a feed-forward active isolation system subjected to actuator output constraints is investigated. Distributed parameter models are developed to analyze the system response, and to produce a transfer matrix for the design of an integrated passive-active isolation system. Cost functions comprising a combination of the vibration transmission energy and the sum of the squared control forces are proposed. The example system considered is a rigid body connected to a simply supported plate via two passive-active isolation mounts. Vertical and transverse forces as well as a rotational moment are applied at the rigid body, and resonances excited in elastic mounts and the supporting plate are analyzed. The overall isolation performance is evaluated by numerical simulation. The simulation results are then compared with those obtained using unconstrained control strategies. In addition, the effects of waves in elastic mounts are analyzed. It is shown that the control strategies which rely on tmconstrained actuator outputs may give substantial power transmission reductions over a wide frequency range, but also require large control force amplitudes to control excited vibration modes of the system. Expected power transmission reductions for modified control strategies that incorporate constrained actuator outputs are considerably less than typical reductions with unconstrained actuator outputs. In the frequency range in which rigid body modes are present, the control strategies can only achieve 5-10 dB power transmission reduction, when control forces are constrained to be the same order of the magnitude as the primary vertical force. The resonances of the elastic mounts result in a notable increase of

关键词： passive-active isolation transfer matrix control effort constraint feedforward control

A survey on vision-based UAV navigation

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Geo-Spatial Information Science 2018年第1期21卷 21-32页

作者： Yuncheng Lu Zhucun Xue Gui-song Xia Liangpei Zhang State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina

Research on unmanned aerial vehicles(UAV)has been increasingly popular in the past decades,and UAVs have been widely used in industrial inspection,remote sensing for mapping&surveying,rescuing,and so ***,the limited autonomous navigation capability severely hampers the application of UAVs in complex environments,such as GPS-denied ***,researchers mainly focused on the use of laser or radar sensors for UAV *** the rapid development of computer vision,vision-based methods,which utilize cheaper and more flexible visual sensors,have shown great advantages in the field of UAV *** purpose of this article is to present a comprehensive literature review of the vision-based methods for UAV *** on visual localization and mapping,obstacle avoidance and path planning,which compose the essential parts of visual ***,throughout this article,we will have an insight into the prospect of the UAV navigation and the challenges to be faced.

关键词： Unmanned aerial vehicles(UAV) visual SLAM obstacle avoidance path planning

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明末清初太阳视差在中国的传播

西北大学学报（自然科学版） 2016年第4期46卷 619-624页

作者：张祺宋芝业内蒙古师范大学科学技术史研究院内蒙古呼和浩特010022

明末清初之际,太阳视差传入中国,并被积极引入官方历法。从《崇祯历书》到《历象考成后编》均对其进行了不同程度的整理与修正,理论层面上已经与西方相差不远,但由于中国天文学以实用为中心的价值取向,仅将其作为历法计算的重要参数,未... 详细信息

明末清初之际,太阳视差传入中国,并被积极引入官方历法。从《崇祯历书》到《历象考成后编》均对其进行了不同程度的整理与修正,理论层面上已经与西方相差不远,但由于中国天文学以实用为中心的价值取向,仅将其作为历法计算的重要参数,未能产生类似于西方的影响。通过对比几部官方历法中太阳视差的相关记述,研究清代历算家对该项知识的3次主要修改,并在此基础上分析清代历算家对太阳视差的认识程度以及科学诉求。

关键词：视差天文单位历法

Identifying the Risk of SARS-CoV-2 Infection and Environmental Monitoring in Airborne Infectious Isolation Rooms(AIIRs)

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Virologica Sinica 2020年第6期35卷 785-792页

作者： zhi-Gang song Yan-Mei Chen Fan Wu Lin Xu Bang-Fang Wang Lei Shi Xiao Chen Fa-Hui Dai Jia-Lei She Jian-Min Chen Edward CHolmes Tong-Yu Zhu Yong-Zhen Zhang Shanghai Public Health Clinical Center State Key Laboratory of Genetic EngineeringSchool of Life SciencesFudan UniversityShanghai 201508China College of Marine Sciences South China Agricultural UniversityGuangzhou 510642China Department of Environmental Science and Engineering Fudan UniversityShanghai 200438China Marie Bashir Institute for Infectious Diseases and Biosecurity School of Life and Environmental Sciences and School of Medical SciencesThe University of SydneySydneyNSW 2006Australia

Healthcare workers(HCWs)are at high risk of occupational exposure to the new pandemic human coronavirus,SARSCoV-2,and are a source of nosocomial transmission in airborne infectious isolation rooms(AIIRs).Here,we performed comprehensive environmental contamination surveillance to evaluate the risk of viral transmission in AIIRs with 115 rooms in three buildings at the Shanghai Public Health Clinical Center,Shanghai,during the treatment of 334 patients infected with *** results showed that the risk of airborne transmission of SARS-CoV-2 in AIIRs was low(1.62%,25/1544)due to the directional airflow and strong environmental hygiene ***,we detected viral RNA on the surface of foot-operated openers and bathroom sinks in AIIRs(viral load:55.00–3154.50 copies/mL).This might be a source of contamination to connecting corridors and object surfaces through the footwear and gloves used by *** risk of infection was eliminated by the use of disposable footwear covers and the application of more effective environmental and personal hygiene *** the help of effective infection control procedures,none of 290 HCWs was infected when working in the AIIRs at this *** study has provided information pertinent for infection control in AIIRs during the treatment of COVID-19 patients.

关键词： SARS-CoV-2 COVID-19 Nosocomial transmission AIIRs Environmental sampling

An efficient method for computing excess free energy of liquid

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Science China Chemistry 2018年第1期61卷 135-140页

作者： Jianing song Linqiong Qiu John Z.H. Zhang School of Chemistry and Molecular Engineering East China Normal University Shanghai 200062 China NYU-ECNU Center for Computational Chemistry at NYU ShanghaL Shanghai 200062 China State Key Laboratory of Precision Spectroscopy East China Normal University Shanghai 200062 China Department of Chemistry New York University NY NY 10003 USA

We present a new theoretical method for efficient calculation of free energy of liquid. This interaction entropy method allows one to compute entropy and free energy of liquid from standard single step MD(molecular dynamics) simulation directly in liquid state without the need to perform MD simulations at many intermediate states as required in thermodynamic integration or free energy perturbation methods. In this new approach, one only needs to evaluate the interaction energy of a single(fixed) liquid molecule with the rest of liquid molecules as a function of time from a standard MD simulation of liquid and the fluctuation of distribution of this interaction energy is then used to calculate the interaction entropy of the liquid. Explicit theoretical derivation of this interaction entropy approach is provided and numerical calculations for the benchmark liquid water system were carried out using three different water models. Numerical analysis of the result was performed and comparison of the computational result with experimental data and other theoretical results were provided. Excellent agreement of calculated free energies with the experimental data using TIP4 P model is obtained for liquid water.

关键词： excess free energy liquid MD simulation interaction entropy

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NodeRank:一种高效软硬件划分算法

计算机学报 2013年第10期36卷 2033-2040页

作者：陈志武继刚宋国治陈金亮天津工业大学计算机科学与软件学院天津300387

软硬件协同设计是现代嵌入式系统开发的核心技术,如何将系统功能划分到软件和硬件部分上是软硬件协同设计的关键环节.文中将软硬件划分问题看作带有动态通信代价的变异0-1背包问题,提出一种基于迭代排序思想的NodeRank算法.该算法通过... 详细信息

软硬件协同设计是现代嵌入式系统开发的核心技术,如何将系统功能划分到软件和硬件部分上是软硬件协同设计的关键环节.文中将软硬件划分问题看作带有动态通信代价的变异0-1背包问题,提出一种基于迭代排序思想的NodeRank算法.该算法通过迭代排序计算结点通信代价的期望值,进而求解背包问题,构造出软硬件划分问题的优质启发解.实验结果证明,在计算-通信代价均衡,弱实时性约束条件下,NodeRank对边点比大于等于2的任务图的处理结果与目前已知效果最好的禁忌搜索方法的平均性能差距不超过1.2%,而平均时间开销可以节约95%.在通信代价较高的条件下,NodeRank与禁忌搜索相比,可提升性能达3.5%,并节约时间超过75%.

关键词：软硬件划分启发式算法 0-1背包问题迭代排序

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一种基于非基因信息的免疫记忆优化算法

物理学报 2015年第14期64卷 25-33页

作者：宋丹樊晓平刘钟理中南大学信息科学与工程学院长沙410083 湖南财政经济学院信息管理系长沙410205

为提高人工免疫优化算法的优化能力,将非基因信息的记忆机制引入智能算法,提出了一种基于非基因信息的免疫记忆优化算法.算法通过对先验知识(非基因信息)的短期记忆并指导后续进化,降低盲目搜索和重复搜索,增加了搜索的智能性和有效性.... 详细信息

为提高人工免疫优化算法的优化能力,将非基因信息的记忆机制引入智能算法,提出了一种基于非基因信息的免疫记忆优化算法.算法通过对先验知识(非基因信息)的短期记忆并指导后续进化,降低盲目搜索和重复搜索,增加了搜索的智能性和有效性.结合标准测试函数在高维下的仿真实验表明,与其他智能算法相比,新算法在收敛速度、收敛精度和全局收敛性方面均优于对比算法.此外,在超高维下的仿真结果表明新算法具有在大规模维度解空间中的全局寻优能力.

关键词：优化算法免疫记忆非基因信息数值计算

Making central-local relations work: Comparing America and China environmental governance systems

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Frontiers of Environmental Science & Engineering 2007年第4期1卷 418-433页

作者： Dan GUTTMAN song Yaqin Center for Industrial Development and Environmental Governance School of Public Policy and ManagementTsinghua UniversityBeijing 100084China School of Law Shanghai Jiaotong UniversityShanghai 200030China Washington Center for Study of American Government Johns Hopkins UniversityWashington D.C.20036USA Program on Governance for Sustainable Development Bren School for Environmental Science and ManagementUniversity of CaliforniaSanta Barbara 93106USA School of Law Peking UniversityBeijing 100084China

The challenge of making central requirements work at local levels is a common problem for environmental governance throughout the *** can learn from one another’s approaches,but must understand the local con-text in which they are *** paper compares the features of the China and US environmental governance systems that need be understood by those working between the *** features include:(1)common values which shape the environmental governance choices in both countries,but which may have different practical meanings in each country;(2)America’s common law-based environmental governance system,and China’s civil law system,which involves plan(s)as well as law;(3)America’s Federal central-local system,and China’s unitary central local *** paper con-cludes by suggesting areas in which further comparative understanding may be of value,including:(1)better under-standing of the role of plan and law in China’s governance system;(2)comparing the American Federal-state agreement system for implementation of environmental law with the China central-local system of target responsibility agreements for plan implementation;(3)improving understanding of nongovernmental resources needed to assure compliance with environmental laws and plans;(4)identifying institutions that can coordinate central-local and cross-border environmental governance.

关键词： comparative environmental governance law and plan central-local coordination target responsibility system

5%定虫隆与4.5%高效氯氰菊酯乳油混剂对小菜蛾的室内毒力测定

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农药 2007年第5期46卷 353-354页

作者：高志强宋仲容何家洪重庆文理学院化学与环境科学系重庆永川402168

采用浸叶法在室内条件下测定5%定虫隆、4.5%高效氯氰菊酯单剂以及不同配比混剂对小菜蛾幼虫的毒力。室内毒力测定结果表明,5%定虫隆与4.5%高效氯氰菊酯4种混剂对小菜蛾均有显著的增效作用,其中混配2的增效作用最显著,其共毒系数最高为36... 详细信息

采用浸叶法在室内条件下测定5%定虫隆、4.5%高效氯氰菊酯单剂以及不同配比混剂对小菜蛾幼虫的毒力。室内毒力测定结果表明,5%定虫隆与4.5%高效氯氰菊酯4种混剂对小菜蛾均有显著的增效作用,其中混配2的增效作用最显著,其共毒系数最高为367.22。

关键词： 5%定虫隆 4.5%高效氯氰菊酯小菜蛾室内毒力测定增效作用