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Different topological phase transitions in the Su–Schrieffer–Heeger model under different disorder structures

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Chinese Physics B 2024年第9期33卷 217-221页

作者： yan gu Zhanpeng Lu Shanxi Vocational University of Engineering Science and Technology Jinzhong 030619China Institute of Theoretical Physics and State Key Laboratory of Quantum Optics and Quantum Optics Devices Shanxi UniversityTaiyuan 030006China

We investigate the topological phase transition in the Su–Schrieffer–Heeger model with the long-range hopping and quasi-periodic *** numerically calculating the real-space winding number,we obtain topological phase diagrams for different disordered *** diagrams suggest that topological phase transitions are different by selecting the specific disordered *** quasi-periodic modulation is applied to intracell hopping,the resulting disorder induces topological Anderson insulator(TAI)phase with high winding number(W=2),but the topological states are destroyed as the disorder ***,when intercell hoppings are modulated quasi-periodically,both TAI phase and the process of destruction and restoration of topological zero modes can be induced by *** topological states remain robust even under strong disorder *** work demonstrates that disorder effects do not always disrupt topological states;rather,with a judicious selection of disordered structures,topological properties can be preserved.

关键词： topological insulator quasi-periodic modulation

Polychlorinated dibenzo-p-dioxins and dibenzofurans in flue gas emissions from municipal solid waste incinerators in China

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第9期9卷 1296-1303页

作者： Tong CHEN Yue-ling gu Jian-hua yan Xiao-dong LI Sheng-yong LU Hui-fen DAI Ke-fa CEN State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China School of Medicine Zhejiang University Hangzhou 310058 China

Polychlorinated dibenzo-p-dioxins and furans （PCDD/Fs） emissions in flue gas from two types of municipal solid waste incinerators （MSWIs） most commonly used in China were investigated in this study. The selected incinerators include two grate-type MSWIs： MSWI-A （350 t/d） and MSWI-B 050 t/d）, and two fluidized bed MSWIs： MSWI-C （400 t/d） and MSWI-D （400 t/d）, which are all equipped with semi-dry lime scrubber and bag filter except MSWI-D equipped with cyclone and wet scrubber （WS） as air pollutant control device （APCD）. Results indicated that the emission concentration and the international toxic equivalents （I-TEQs） of the PCDD/Fs from the stacks were in the range of 1.210-10.273 ng/Nm^3 and 0.019-0.201 ng I-TEQ/Nm^3, respectively. They were greatly lower than the emission regulation standard of PCDD/Fs in China （1.0 ng I-TEQ/Nm^3）. However, only the PCDD/Fs emission level from MSWI-C was below 0.1 ng I-TEQ/Nm^3. Although the homologue profiles were distinct, the contributions of the 2,3,7,8-subsituted congeners to the total I-TEQ were similar among all the investigated MSWIs. Two major 2,3,7,8-substituted congeners, 2,3,4,7,8-PeCDF and 1,2,3,7,8-PeCDD, account for 47% and 9% （average values） of the total I-TEQ values, respectively. The correlation between PCDD/Fs levels and composition of flue gas was also discussed.

关键词： Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) Municipal solid waste incinerator (MSWI) Grate Fluidized bed

Dynamic Concept of Returns to Scales and Its Characteristics on Production Frontier in Intersection Form

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Acta Mathematicae Applicatae Sinica 2011年第3期27卷 355-366页

作者： Quan-ling Wei Hong yan Institute of Operations Research and Mathematical Economics Renmin University of China Beijin 100872 China Department of Logistics The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong

This paper gives a dynamic concept and a new non-parametric method for evaluating returns to scale（RTS） of economic units with multiple inputs and *** is frequently noticed that when we increase the input of a decision making unit（DMU） with a certain status of RTS,different status of RTS is *** example,when we increase the input of a DMU with constant RTS under the traditional method,a decreasing RTS is often observed instead of the expected constant *** thus define the RTS of each DMU in both input expansion and contraction regions *** research starts from transferring the production possibility set into the intersection form,by giving the explicit linear inequality representation of production *** RTS structural characteristics of DMUs＇ on the production frontier are *** of RTS of those DMUs on the production frontier include increasing RTS,constant RTS,decreasing RTS,saturated RTS and evidence of *** and suficient conditions for RTS evaluation are *** definition and evaluation method given here provide more detailed economic characteristics of DMU for policy makers.

关键词： DEA production possibility set returns to scale

Angle-closure glaucoma with attenuated mucopolysaccharidosis typeⅠin a Chinese family

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International Journal of Ophthalmology(English edition) 2021年第11期14卷 1799-1801页

作者： yan Liu Li Dai Ran Long Fu Quan Chao gu ling Yu Department of Ophthalmology the Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Radiology the Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina

Dear Editor,I am *** Liu,from the Department of Ophthalmology,the Afliated Hospital of Southwest Medical University,Luzhou,China.I write to present a rare case of angle-closure glaucoma(ACG)with attenuated mucopolysac... 详细信息

关键词： closure glaucoma China

An Estimation Method for Multi-channel EEG Data Based on Canonical Correlation Analysis

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Chinese Journal of Electronics 2015年第3期24卷 569-572页

作者： yan Zheng WAN Xiaojiao ling Chaodong Department of Information Science and Engineering Huaqiao University

Electroencephalogram(EEG) signal is often contaminated by electronic noise as well as movement artifacts. This paper presented an algorithm based on Canonical correlation analysis(CCA) to estimate multichannel EEG data. Different from previous studies, in which CCA was mainly used to detect the invariant features specific to each brain state, in this paper, the canonical variates computed by CCA were used to reconstruct the multi-channel EEG data. Firstly, two data sets, EEG signals and the reference signals based on prior knowledge were constructed. Next, canonical variates were computed by pro jecting the two data sets onto basis vectors. Finally,a least squares solution was used to estimate the multichannel EEG data. The experiment results suggested that the algorithm is capable of reconstructing the actual specific components with high quality. We also hint future possible application of the algorithm in the estimation of functional connectivity patterns at the end of the paper.

关键词： Electroencephalogram(EEG) Canonical correlation analysis(CCA) Canonical variates

Digital Channelization Technology for HF Communication Base on Fast Filter Bank

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China Communications 2018年第9期15卷 35-45页

作者： Yixin Fan Fanglin gu Xiaobo Tan ling Wang College of Electronic and Information Engineering Hunan University College of Electronic Science National University of Defense Technology Model Office in Aerospace Industry Group Corporation PLA Rocket Force

Channelization typically realized by digital filter banks is an important topic in high frequency(HF) communication and software defined radios(SDR) areas. Channelization has a rigorous requirement for the characteristic of frequency response, e.g., steep transitional band and sharp decay. To address this issue, we investigated the feasibility and implementation of applying fast filter bank(FFB) in channelization in this paper. We analyzed the butterfly structure of FFB similar with fast Fourier transform(FFT), in which prototype sub-filters are cascaded to achieve a low complexity. Hence, it is suitable for designing filter bank with steep transitional band and sharp decay in stop-band. Moreover, we designed a pipelined structure of FFB to achieve a balance between area and performance. Design example shows that FFB has lower computational complexity compared with the other filter banks.

关键词： fast filter bank (FFB) high frequency (HF) channelization software defined radio (SDR)

Construction of [1]rotaxanes with pillar[5]arene as the wheel and terpyridine as the stopper

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Chinese Chemical Letters 2020年第1期31卷 81-83页

作者： ling-ling Zhao Ying Han Chao-guo yan College of Chemistry & Chemical Engineering Yangzhou University

The condensation reaction ofω-aminoalkyleneamide-functionalized pillar[5]arenes with 2-(4-([2,2’:6’,2〃-terpyridin]-4’-yl)phenoxy)acetic acid or 4-(4-([2,2’:6’,2"-terpyridin]-4’-yl)phenoxy)butanoic acid in dry chloroform at room temperature under the catalysis of HOBT/EDCl resulted in novel pillar[5]arene diamido-bridged terpyridine derivatives.~1 H NMR and 2 D NOESY spectra clearly indicated that the interesting[1]rotaxanes were formed by longer alkylene such as propylene,butylene and hexylenediamido chains threading into the cavity of the pillar[5]arene and with larger terpyridine acting as the ***,the shorter ethylenediamido chain only exists outer of cavity of pillar[5]arene and the molecule exist on free form.

关键词： Pillararene TerpyridineRotaxane Amidation Interlocked molecule

MODIFIED BOTTLENECK-BASED PROCEDURE FOR LARGE-SCALE FLOW-SHOP SCHEDUling PROBLEMS WITH BOTTLENECK

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Chinese Journal of Mechanical Engineering 2006年第3期19卷 356-361页

作者： ZUO yan gu Hanyu XI Yugeng Institute of Automation Shanghai Jiaotong University Shanghai 200240 China

A new bottleneck-based heuristic for large-scale flow-shop scheduling problems with a bottleneck is proposed, which is simpler but more tailored than the shifting bottleneck （SB） procedure. In this algorithm, a schedule for the bottleneck machine is first constructed optimally and then the non-bottleneck machines are scheduled around the bottleneck schedule by some effective dispatching rules. Computational results show that the modified bottleneck-based procedure can achieve a tradeoff between solution quality and computational time comparing with SB procedure for medium-size problems. Furthermore it can obtain a good solution in quite short time for large-scale scheduling problems.

关键词： Flow-shop scheduling problem Heuristic Bottleneck machine

On Hilbert Coefficients of Filtrations

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Chinese Annals of Mathematics,Series B 2007年第5期28卷 543-554页

作者： yan gu guangjun ZHU Zhongming TANG Department of Mathematics Suzhou University Suzhou 215006 Jiangsu China.

Let F be a Hilbert filtration with respect to a Cohen-Macaulay module M. When G（F, M） and FK（F,M） have almost maximal depths, the Hilbert coefficients gi（F, M） is calculated. In the general case, an upper bound ... 详细信息

关键词： Hilbert coefficients Fiber cones Depth