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Improved artificial bee colony algorithm with mutual learning

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Journal of Systems Engineering and Electronics 2012年第2期23卷 265-275页

作者： yu Liu Xiaoxi ling yu Liang Guanghao Liu School of Software Dalian University of Technology Dalian 116024 P. R. China Civil Aviation Flight University of China Guanghan 618307 E R. China

The recently invented artificial bee colony （ABC） al- gorithm is an optimization algorithm based on swarm intelligence that has been used to solve many kinds of numerical function optimization problems. It performs well in most cases, however, there still exists an insufficiency in the ABC algorithm that ignores the fitness of related pairs of individuals in the mechanism of find- ing a neighboring food source. This paper presents an improved ABC algorithm with mutual learning （MutualABC） that adjusts the produced candidate food source with the higher fitness between two individuals selected by a mutual learning factor. The perfor- mance of the improved MutualABC algorithm is tested on a set of benchmark functions and compared with the basic ABC algo- rithm and some classical versions of improved ABC algorithms. The experimental results show that the MutualABC algorithm with appropriate parameters outperforms other ABC algorithms in most experiments.

关键词： artificial bee colony (ABC) algorithm numerical func- tion optimization swarm intelligence mutual learning.

Estimation of Treatment Effects in Nonlinear Models with Unobserved Confounding

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Acta Mathematicae Applicatae Sinica 2023年第2期39卷 320-336页

作者： yu-ling LI Jun WANG Research Center for Applied Mathematics and Interdisciplinary Sciences Beijing Normal UniversityZhuhai 519087China yunnan Key Laboratory of Statistical Modeling and Data Analysis Yunnan UniversityKunming 650091China

Estimation of treatment effects is one of the crucial mainstays in economics and sociology *** problem will become more serious and complicated if the treatment variable is endogenous for the presence of unobserved *** estimation and conclusion are likely to be biased and misleading if the endogeny of treatment variable is *** this article,we propose the pseudo maximum likelihood method to estimate treatment effects in nonlinear *** proposed method allows the unobserved confounding and random error terms to exist in an arbitrary relationship(such as,add or multiply),and the unobserved confounding have different influence directions on treatment variables and outcome *** proposed estimator is consistent and asymptotically normally *** studies show that the proposed estimator performs better than the special regression estimator,and the proposed method is stable for various distribution of error ***,the proposed method is applied to the real data that studies the influence of individuals have health insurance on an individual’s decision to visit a doctor.

关键词： nonlinear models quasi likelihood estimator stable treatment effects unobserved confounding

Joint power allocation and subcarrier pairing in OFDM-based cooperative relaying system

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The Journal of China Universities of Posts and Telecommunications 2012年第1期19卷 24-30页

作者： DAI Cui-qin ZHAO Xiao-yu ZHANG zu-fan Chongqing Key Lab of Mobile Communication Technology Chongqing University of Posts and TelecommunicationsChongqing 400065China

This paper proposes rate-maximized （MR） joint subcarrier pairing （SP） and power allocation （PA）（MR-SP＆PA）, a novel scheme for maximizing the weighted sum rate of the orthogonal-frequency-division multiplexing （OFDM） relaying system with a decode-and-forward （DF） relay. MR-SP＆PA is based on the joint optimization of both SP and power allocation with total power constraint, and formulated as a mixed integer programming problem in the paper. The programming problem is then transformed to a convex optimization problem by using continuous relaxation, and solved in the Lagrangian dual domain. Simulation results show that MR-SP＆PA can maximize the weighted sum rate under total power constraint and outperform equal power allocation （EPA） and proportion power allocation （PCG）.

关键词： OFDM DF relaying power allocation SP MR-SP&PA

Pressure and velocity cross-spectrum of normal modes in low-frequency acoustic vector field of shallow water and its application

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Journal of Systems Engineering and Electronics 2015年第2期26卷 241-249页

作者： yun yu Qing ling Jiang Xu Naval Academy of Armament

The pressure and horizontal particle velocity combined descriptions in the very low frequency acoustic field of shallow wa- ter integrated with the concept of effective depth of Pekeris wave- guide is proposed, especially the active component of the pressure and horizontal particle velocity cross-spectrum, also called ho- rizontal complex cross acoustic intensity, when only two normal modes are trapped in the waveguide. Both the approximate theo- retic analysis and the numerical results show that the sign of the horizontal complex cross acoustic intensity active component is independent of the range when vertically deployed receiving dual sensors are placed in appropriate depths, the sum of which is equal to the waveguide effective depth, so it can be used to tell whether the sound source is near the surface or underwater; while the range rate is expected to be measured by utilizing the sign distribution characteristic of the reactive component. The further robustness analysis of the depth classification algorithm shows that the existence of shear waves in semi infinite basement and the change of acoustic velocity profiles have few effects on the application of this method, and the seabed attenuation will limit the detection range, but the algorithm still has a good robustness in the valid detection range.

关键词： low frequency acoustic vector field effective depth complex cross acoustic intensity active component target depth classificatio

High-capacity Li-rich Mn-based Cathodes for Lithium-ion Batteries

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Chinese Journal of Structural Chemistry 2020年第1期39卷 20-25,1页

作者： YIN zu-Wei LI Jun-Tao HUANG ling PAN Feng SUN Shi-Gang College of Energy Xiamen UniversityXiamen 361005China State Key Lab of Physical Chemistry of Solid Surface College ofChemistry and Chemical EngineeringXiamen UniversityXiamen 361005China School of Advanced Materials Peking UniversityShenzhen Graduate SchoolShenzhen 518055China

Layered Li-rich Mn-based oxides are promising cathode materials for Li-ion batteries due to their high capacity and high operation ***,their commercial applications are hindered by irreversible capacity loss in the first charge-discharge process,voltage decay during cycling,inefficient cyclability and rate *** attempts have been performed to solve such issues,including the mechanism study and strategies to improve the electrochemical *** article provides a brief review and future perspective on the main challenges of the high-capacity Li-rich Mn-based cathodes for Li-ion batteries.

关键词： Li-ion batteries Li-rich Mn-based cathodes the first charge-discharge process voltage decay cyclability rate capability

Molecular engineering of dendrimer nanovectors for siRNA delivery and gene silencing

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Frontiers of Chemical Science and Engineering 2017年第4期11卷 663-675页

作者： yu Cao Xiaoxuan Liu ling Peng . Aix-Marseille Université CNRS Centre Interdisciplinaire de Nanoscience de Marseille UMR 7325 Equipe Labellisée Ligue Contre le Caner 13288 Marseille France.. State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases Center of Drug Discovery Center of Advanced Pharmaceuticals and Biomaterials China Pharmaceutical University Nanjing 210009 China

Small interfering RNA （siRNA） therapeutics hold great promise to treat a variety of diseases, as long as they can be delivered safely and effectively into cells. Dendrimers are appealing vectors for siRNA delivery by virtue of their well-defined molecular architecture and multivalent cooperativity. However, the clinical translation of RNA therapeutics mediated by dendrimer delivery is hampered by the lack of dendrimers that are of high quality to meet good manufacturing practice standard. In this context, we have developed small amphiphilic dendrimers that self-assemble into supramolecular structures, which mimic high-generation dendrimers synthesized with cova- lent construction, yet are easy to produce in large amount and superior quality. Indeed, the concept of supramolecular dendrimers has proved to be very promising, and has opened up a new avenue for dendrimer-mediated siRNA delivery. A series of self-assembling supramolecular dendrimers have consequently been established, some of them out-performing the currently available nonviral vectors in delivering siRNA to various cell types in vitro and in vivo, including human primary cells and stem cells. This short review presents a brief introduction to RNAi therapeutics, the obstacles to their delivery and the advantages of dendrimer delivery vectors as well as our bio-inspired struc^rally flexible dendrimers for siRNA delivery. We then highlight our efforts in creating self- assembling amphiphilic dendrimers to construct supramo- lecular dendrimer nanosystems for effective siRNA delivery as well as the related structural alterations to enhance delivery efficiency. The advent of self-assembling supramolecular dendrimer nanovectors holds great pro- mise and heralds a new era of dendrimer-mediated delivery of RNA therapeutics in biomedical applications.

关键词： gene therapy RNAi therapeutics dendrimer,nanovectors gene silencing

Filament geometrical model and nozzle trajectory analysis in the fused deposition modeling process

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 370-376页

作者： yu-zhen JIN Jia-fan ZHANG Ying WANG zu-chao ZHU State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China Faculty of Mechanical Engineering & Automation Zhejiang Sci- Tech University Hangzhou 310018 China

The geometrical model of the filament during the fused deposition modeling (FDM) process was firstly proposed based on three different models, tractrix, parabola, and catenary. Comparing with the actual measured filament curves on the Stratasys 1600 FDM machine, it is indicated that the tractrix model had the best agreement with the actual measured curves. With the analytical simulation, the nozzle trajectories in the straight-line deposition road, circle road, and arbitrary continuous curve road were deduced, according to the traxtric based geometrical model of the filament.

关键词： Fused deposition modeling (FDM) Filament geometrical model Nozzle trajectory

New insights into mercury removal mechanism on CeO2- based catalysts： A first-principles study

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Frontiers of Environmental Science & Engineering 2018年第2期12卷 107-115页

作者： ling Li yu He Xia Lu Forestry College Guizhou University Guiyang 550025 China Key Laboratory of High-Temperature and High-Pressure Study of the Earth's Interior Institute of Geochemistry Chinese Academy of Sciences Guiyang 550081 China State Key Laboratory of Organic-Inorganic Composites Beijing Advanced Innovation Center for Soft MatterScience and Engineering College of Energy Beijing University of Chemical Engineering Beijing 100029 China

First-principles calculanons were performed to investigate the mechamsm of Hg0 adsorpnon and oxidation on CeO2（111）. Surface oxygen acnvated by the reducnon of Ce to Ce a vlta to Hg~ adsorption and oxidation processes. Hg0 was fully oxidized by the surface lattice oxygen on CeO2（111）, without using any other oxidizing agents. HCI could dissociate and react with the Hg adatom on CeO2（111） to form adsorbed Hg CI or CI-Hg-Cl groups, which promoted the desorption of oxidized Hg and prevented CeO2 catalyst deactivation. In contrast, O-H and H-O-H groups formed during HC1 adsorption consumed the active surface oxygen and prohibited Hg oxidation. The consumed surface oxygen was replenished by adding O2 into the flue gas. We proposed that oxidized Hg desorption and maintenance of sufficient active surface oxygen were the rate-determining steps of Hg0 removal on CeO2-based catalysts. We believe that our thorough understanding and new insights into the mechanism of the Hg0 removal process will help provide guidelines for developing novel CeO2-based catalysts and enhance the Hg removal efficiency.

关键词： Elemental mercury removal Surface adsorption Ceria First-principles calculations

Status and trends of carbon emissions research at the county level in China

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Advances in Climate Change Research 2024年第2期15卷 338-352页

作者： Ang-zu CAI Ru GUO yu-Hao ZHANG Jiang WU College of Environmental Science and Engineering Institute of Environmental Planning and ManagementTongji UniversityShanghai 200092China Institute of Carbon Neutrality Tongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China College of Architecture and Urban Planning Tongji UniversityShanghai 200092China Megacity Elaborated Urban Governance Institute Tongji UniversityShanghai 200092China

This study provides a comprehensive overview of the challenges to achieving carbon neutrality at the county level in China and offers targeted recommendations,laying the groundwork for future specialized research in this area.A total of 283 relevant studies(2004-2023)were analyzed to assess county-level carbon emissions through three phases:bibliometric analysis,frontier analysis,and future *** findings reveal that publication trends were largely influenced by domestic and foreign *** cluster discerns ten primary themes,ranging from conceptual frameworks to research *** frontier analysis of the literature highlights the leading research areas,which include carbon neutrality pathway,driving factors,spatiotemporal variation of carbon emissions,the co-effects of pollutants and carbon reduction,and carbon emissions in China's rural *** from the results of bibliometric and frontier analyses,this study elucidates the recommendations for achieving carbon neutrality at the county level from three perspectives:effective regional policy guidance,emphasis on ecological conservation,and the deployment of advanced carbon reduction and sequestration *** study enriches the body of knowledge on carbon emissions at the county level and holds significant implications for China's comprehensive push towards achieving its carbon neutrality objectives.

关键词： Carbon emissions Emission reduction County Carbon neutrality Sustainability