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Synthesis and Structural Characterization of a New Hydrogen-bonded Polyrotaxane of [Co(H_2O)_6]_(2+) with 1,1′-(Propane-1,3-diyl)dipyridinium-4-carboxylate

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Chinese Journal of Structural Chemistry 2006年第8期25卷 957-964页

作者： JIANG Ning-yi LI Song-lin Department of Chemistry College of Science Tianjin University Tianjin 300072 China

A new double betaine 1,1′-（propane-1,3-diyl）dipyridinium-4-carboxylate L has been synthesized. Reaction of 1, 1′-（propane-1,3-diyl）dipyridinium-4-carboxylate tetrahydrate 1 with Co（ClO4）2-6H2O leads to the formation of a new Co（Ⅱ） coordination compound, namely [Co（H2O）6]-2H2O-2L-2ClO4 2. The crystal structures of 1 and 2 have been determined by single-crystal X-ray diffraction method. Crystal data for 1. monoclinic, space group C2/c, a = 18.945（4）, b = 7.700（2）, c = l 1.888（2）A,β = 101.67（3）°, V = 1698.3（6） A^3, Z = 4, F（000） = 760.0, Dc = 1.402 g/cm^3, the final R = 0.0607 and wR = 0.1607 for 950 observed reflections （1 〉 2σ（I））; and those for 2： monoclinic, space group P21/c, a = 17.982（1）, b = 15.879 （1）, c = 7.0716（5）/A,β= 100.675（1）°, V= 1984.3（3） ,A^3 Z= 4, F（000） = 1010.0, Dc = 1.631 g/cm^3, the final R = 0.0316 and wR = 0.0896 for 3784 observed reflections （1 〉20（I））. Crystal structure analysis indicates that in 1, molecules of L in a ＂V-shaped＂ conformation are linked to chains sustained by O-H…O hydrogen bonds between carboxylate groups and solvent water molecules. The chains are joined by O-H…O and C-H…O hydrogen bonds to further expand into a three-dimensional structure. For 2, molecules of L in a ＂Z-shaped＂ conformation are linked by hydrogen bonds between carboxylate groups and aqua ligands to form a chain of loops running down the b axis. The （2D→2D） polythreading in compound 2 represents the mode of parallel interpenetration of 2D sheets, having polyrotaxane character.

关键词： 1,1′-(propane-1,3-diyl)dipyridinium-4-carboxylate polyrotaxane hydrogen bonding betaine derivative

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Tor被动流量分析综述

软件学报 2025年第1期36卷 253-288页

作者：梅汉涛程光朱怡霖周余阳东南大学网络空间安全学院江苏省泛在网络安全工程研究中心(东南大学) 网络空间国际治理研究基地(东南大学) 紫金山实验室

随着网络的蓬勃发展,用户隐私正面临着前所未有的挑战.人们开发出多种匿名通信系统来保护隐私,第2代洋葱路由Tor (the second-generation onion router)是目前最为广泛使用的匿名通信系统.然而,卓越的匿名性也使之成为不法分子犯罪的温... 详细信息

随着网络的蓬勃发展,用户隐私正面临着前所未有的挑战.人们开发出多种匿名通信系统来保护隐私,第2代洋葱路由Tor (the second-generation onion router)是目前最为广泛使用的匿名通信系统.然而,卓越的匿名性也使之成为不法分子犯罪的温床,如今Tor中充斥着非法交易、网络犯罪等. Tor被动流量分析通过被动观察网络流量对Tor进行去匿名化,已成为最热门的去匿名化技术.从Tor与流量分析基本概念出发,介绍Tor被动流量分析技术的应用场景与威胁模型.按照技术类型将现有工作分为流量分类技术与流关联技术,依据分析流程分别对比其流量采集方法、特征提取方法、使用算法.最后探讨当前研究面临的主要挑战与未来可能的研究趋势.

关键词： Tor 流量分析流量分类网站指纹流关联

Topological Recursion Relations from Pixton Relations

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Acta Mathematica Sinica,English Series 2017年第4期33卷 470-494页

作者： yi Jie lin Jian ZHOU Department of Mathematical Sciences Tsinghua University Beijing 100084 P. R. China

We propose an algorithm to derive tautological relations from Pixton relations. We carry out this algorithm explicitly to derive some results in genus 0, 1, 2, 3 and analyze the possibility to generalize to higher gen... 详细信息

关键词： Faber–Zagier relations Pixton relations topological recursion relations Gromov–Witten invariants

The effects of ion screening on neutrino-nucleus interactions in core-collapse supernova explosions

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Research in Astronomy and Astrophysics 2010年第7期10卷 689-695页

作者： Xiong-Ping Xia lin yi Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

The effects of ion screening in stellar core collapses are investigated based on a new progenitor star model. Simulation results show that ion screening slightly affects the leptons and decreases explosion energy, which is a negative factor for energy transfer supernova explosions. We also investigate the effect on type Ⅱ-supernova explosions of neutrino-nucleus elastic scattering based on the new progenitor star model. It is shown that, compared with the previously calculated results, neutrinos-nucleus elastic scattering in stellar core collapses is more severe, leading to an obvious reduction of the neutrino leakage energy loss and an increase of supernova explosion energy.

关键词： stars supernovae general -- neutrino-nucleus

Anomalous Optical and Electronic Properties of CaTiO3 Perovskites

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Communications in Theoretical Physics 2007年第3X期48卷 563-570页

作者： LIU Hui-Ping DUAN yi-Feng yi lin Department of Physics and State Key Laboratory of Laser Technology Huazhong University of Science and TechnologyWuhan 430074 China

With the help of the first-prlnciples full potential linearized augmented plane wave method, absorption coefficients, reflect/vity, dielectric behavior and electronic properties, including electronic energy bands, density of states and charge density distributions, are studied for the tetragonal and cubic CaTiO3. By considering the thermal expansion effects, an approximate method is proposed for the study of the stability of ground state and a tendency of phase transition, based on the minimum free energy principle. Subsequently, numerical calculations are carried out by using the first-principles perturbation method. We demonstrate that the high-temperature phase is cubic. It is shown that optical spectra in tetragonal phase exhibit single-peak feature and differ from multi-peak character in cubic. We find that strong orbital hybridization results in the co-valent bonds between Ti 3d and O 2p electrons and forms two-type dipoles （Ti-Ol and Ti-02） in tetragonal, while the Ti-O dipoles are identical in cubic. It is argued that crystal structure determines the dipole distributions and leads to some electron states among which the dipole-dipole transit/on forbidden is a key, causing such anomalous optical phenomena with the insulator characteristics. The predicted charge density distribution and the tendency of phase transition from tetragonal to cubic are in good agreement with experimental observations.

关键词： first-principles calculations CaTiO3 perovskites optical and electronic properties

Novel sutureless transplantation for primary pterygium associated with cysts

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International Journal of Ophthalmology(English edition) 2011年第3期4卷 280-283页

作者： yi Shao, Jing-lin yi Department of Ophthalmology the First Affiliated Hospital of Nanchang University Nanchang 330006 Jiangxi Province China Department of Science education the First Affiliated Hospital of Nanchang University Nanchang 330006 Jiangxi Province China Department of Endocrinology the Third Hospital of Nanchang the Affiliated Nanchang Hospital of Southern Medical University Nanchang 330009 Jiangxi Province China Laboratory of Neurobiology University of California·Irvine Irvine California 92697 USA

AIM: To evaluate the efficacy and safety of a novel sutureless AMT (amniotic membrane transplantation) or CAT (conjunctivolimbal autograft transplantation) using fibrin glue for reconstructing corneoconjunctival surfaces for primary pterygium associated with cysts. METHODS: A prospective descriptive study was made of the period 1 January 2006-1 May 2009. Nine patients with primary pterygium associated with cysts underwent pterygium and cyst excision followed by sutureless AMT or CAT using fibrin glue. RESULTS: During a mean follow-up of 8.00 +/- 0.67 months, all eyes maintained a smooth and stable corneal epithelial surface without recurrent erosion or persistent epithelial defect. The limbal donor site showed the presence of mild depressions without the formation of pseudopterygium. All eyes have good tear secretion function, tear film stability and ocular motility. CONCLUSION: Sutureless transplantation using fibrin glue is safe and effective for restoring a stable corneoconjunctival epithelium in primary pterygium associated with cysts.

关键词： sutureless pterygium cyst AMT CAT

A Comparison of Deterministic, Reliability-Based Topology Optimization under Uncertainties

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Acta Mechanica Solida Sinica 2016年第1期29卷 31-45页

作者： Qinghai Zhao XiaokaiChen Zhengdong Ma yi lin Collaborative Innovation Center of Electric Vehicles in Beijing School of Mechanical Engineering Beijing Institute of Technology Beijing 100081 China Department of Mechanical Engineering University of Michigan MI 48105 USA Beijing Automotive Technology Center Beijing 100081 China

Reliability and optimization are two key elements for structural design. The reliability~ based topology optimization （RBTO） is a powerful and promising methodology for finding the optimum topologies with the uncertainties being explicitly considered, typically manifested by the use of reliability constraints. Generally, a direct integration of reliability concept and topol- ogy optimization may lead to computational difficulties. In view of this fact, three methodologies have been presented in this study, including the double-loop approach （the performance measure approach, PMA） and the decoupled approaches （the so-called Hybrid method and the sequential optimization and reliability assessment, SORA）. For reliability analysis, the stochastic response surface method （SRSM） was applied, combining with the design of experiments generated by the sparse grid method, which has been proven as an effective and special discretization technique. The methodologies were investigated with three numerical examples considering the uncertainties including material properties and external loads. The optimal topologies obtained using the de- terministic, RBTOs were compared with one another; and useful conclusions regarding validity, accuracy and efficiency were drawn.

关键词： reliability-based design optimization topology optimization first-order reliabilitymethod (FORM) stochastic response surface method sparse grid method

An algorithm for trajectory prediction of flight plan based on relative motion between positions

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Frontiers of Information Technology & Electronic Engineering 2018年第7期19卷 905-916页

作者： yi lin Jian-wei ZHANG Hong LIU National Key Laboratory of Fundamental Science on Synthetic Vision Sichuan University National Key Laboratory of Air Traffic Control Automation System Technology Sichuan University

Traditional methods for plan path prediction have low accuracy and stability. In this paper, we propose a novel approach for plan path prediction based on relative motion between positions(RMBP) by mining historical flight trajectories. A probability statistical model is introduced to model the stochastic factors during the whole flight process. The model object is the sequence of velocity vectors in the three-dimensional Earth space. First, we model the moving trend of aircraft including the speed(constant, acceleration, or deceleration), yaw(left, right, or straight), and pitch(climb, descent, or cruise) using a hidden Markov model(HMM) under the restrictions of aircraft performance parameters. Then, several Gaussian mixture models(GMMs) are used to describe the conditional distribution of each moving trend. Once the models are built, machine learning algorithms are applied to obtain the optimal parameters of the model from the historical training data. After completing the learning process, the velocity vector sequence of the flight is predicted by the proposed model under the Bayesian framework, so that we can use kinematic equations, depending on the moving patterns, to calculate the flight position at every radar acquisition cycle. To obtain higher prediction accuracy, a uniform interpolation method is used to correct the predicted position each second. Finally, a plan trajectory is concatenated by the predicted discrete points. Results of simulations with collected data demonstrate that this approach not only fulfils the goals of traditional methods, such as the prediction of fly-over time and altitude of waypoints along the planned route, but also can be used to plan a complete path for an aircraft with high accuracy. Experiments are conducted to demonstrate the superiority of this approach to some existing methods.

关键词： Velocity vector Hidden Markov model Gaussian mixture model Machine learning Plan path prediction Relative motion between positions(RMBP)

GRAPHICAL-BASED RELIABILITY EVALUATION OF MULTIPLE DISTINCT PRODUCTION linES

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Journal of Systems Science and Systems Engineering 2013年第1期22卷 73-92页

作者： yi-Kuei lin Ping-Chen CHANG Department of Industrial Management National Taiwan University of Science & Technology

This paper proposes a graphical-based methodology to evaluate the performance of a manufacturing system in terms of network *** focus on a manufacturing system which consists of multiple distinct production lines.A transformation technique is developed to build the manufacturing system as a manufacturing *** such a manufacturing network,the capacity of each machine is multistate due to failure,partial failure,or ***,this manufacturing network is also regarded as a multistate *** evaluate the probability that the manufacturing network can meet a given demand,where the probability is referred to as the system reliability.A simple algorithm integrating decomposition technique is proposed to generate the minimal capacity vectors that machines should provide to eventually satisfy *** system reliability is derived in terms of such capacity vectors afterwards.A practical application in the context of IC card manufacturing system is utilized to demonstrate the performance evaluation procedure.

关键词： Graphical-based methodology transformation decomposition multiple distinct production lines system reliability