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中国有色金属学会会刊：英文版 2006年第A02期16卷 180-185页

作者：朱鸣芳 CAO Wei-sheng CHEN Shuang-lin XIE Fan-you HONG chun-pyo CHANG y. Austin School of Materials Science and Engineering Southeast University Nanjing 210096 China Department of Materials Science and Engineering University of Wisconsin-Madison 1509 University Avenue Madison WI 53706 USA CompuTherm LLC 437 S. Yellowstone Dr. Suite 217 Madison WI 53719 USA Center for Computer-Aided Materials Processing （CAMP） Department of Metallurgical Engineering Yonsei University Shinchon-dong 134 Seodaemun-ku Seoul 120-749 Korea

A modified cellular automaton (MCA) model has been extended to the ternary alloy system by coupling thermodynamic and phase equilibrium calculation engine PanEngine. In the present model the dendrite growth is driven by the difference between the local equilibrium liquidus temperature and local actual temperature, incorporating the effect of curvature. The local equilibrium liquidus temperature is calculated with PanEngine according to the local liquid concentrations of two solutes, which are determined by numerically solving the species transport equation in the domain. Model validation was carried out through the comparison of the simulated values to the prediction of the Scheil model for solute profiles in the primary dendrites. The simulated data with zero solid diffusivity and limited liquid diffusivity were increasingly close to the Scheil profiles as the solidification rate decreased. The simulated microstructure and microsegregation in an Al-Cu-Mg ternary alloy were compared with those obtained experimentally.

关键词：三元合金体系凝固显微结构模型显微偏析细胞自动机

Allometric models for aboveground biomass of six common subtropical shrubs and small trees

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Journal of Forestry Research 2022年第4期33卷 1317-1328页

作者： Cheng Huang chun Feng yuhua Ma Hua Liu Zhaocheng Wang Shaobo yang Wenjing Wang Songling Fu Han y.H.Chen College of Forestry and Landscape Architecture Anhui Agricultural University130 Changjiang West RoadHefei 230036AnhuiPeople’s Republic of China Faculty of Natural Resources Management Lakehead University955 Oliver RoadThunder BayON P7B 5E1Canada

The aboveground biomass(AGB)of shrubs and small trees is the main component for the productivity and carbon storage of understory vegetation in subtropical secondary ***,few allometric models exist to accurately evaluate understory *** estimate the AGB of five common shrub(diameter at basey(ρ).As expected,the six species possessed greater biomass in their stems compared with branches,with the lowest biomass in the ***-specific allometric models that employed stem diameter and the combined variables of D~2H andρDH as predictors accurately estimated the components and total AGB,with R^(2) values from 0.602 and 0.971.A multi-species shrub allometric model revealed that wood density×diameter×height(ρDH)was the best predictor,with R^(2) values ranging from between 0.81 and 0.89 for the components and total AGB,*** results indicated that height(H)and diameter(D)were effective predictors for the models to estimate the AGB of the six species,and the introduction of wood density(ρ)improved their *** optimal models selected in this study could be applied to estimate the biomass of shrubs and small trees in subtropical regions.

关键词： Aboveground biomass Allometric models Shrubs Small trees Subtropical forests

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桅杆结构有限元模型修正与参数敏感性研究

振动工程学报 2024年第7期37卷 1107-1114页

作者：刘慕广乔磊王雷余先锋张春生谢壮宁张丽华南理工大学土木与交通学院广东广州510641 亚热带建筑与城市科学全国重点实验室广东广州510641 广东省交通规划设计研究院集团股份有限公司广东广州510507 深圳市国家气候观象台广东深圳518040

基于台风“圆规”激励下的实测加速度响应识别了深圳356 m高气象梯度观测塔的模态参数,结合带精英策略的快速非支配排序遗传算法(NSGA-Ⅱ)对气象塔有限元模型进行修正。结果表明:气象塔模态非常密集,且纤绳模态的参与程度较为显著。气象... 详细信息

基于台风“圆规”激励下的实测加速度响应识别了深圳356 m高气象梯度观测塔的模态参数,结合带精英策略的快速非支配排序遗传算法(NSGA-Ⅱ)对气象塔有限元模型进行修正。结果表明:气象塔模态非常密集,且纤绳模态的参与程度较为显著。气象塔X向和y向的基频分别为0.614 Hz和0.603 Hz,其前3阶弯曲模态阻尼比在1%~2%之间。塔身密度、纤绳弹模对塔身模态频率和振型有显著影响,高层纤绳的线质量和塔身弹模对其也有一定影响,但纤绳张力的影响较低。气象塔有限元模型修正后的风致响应高于修正前,并更接近实测结果,验证了修正模型的准确性。

关键词：模型修正风振响应桅杆模态识别实测

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Physio-chemical modeling of the NO_(x)-O_(3) photochemical cycle and the air pollutants’ reactive dispersion around an isolated building

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建筑模拟(英文) 2023年第9期16卷 1735-1758页

作者： yunfei Fu Xisheng Lin Xing Zheng Liangzhu Wang chun-Ho Liu Xuelin Zhang Cruz y.Li K.T.Tse Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Future Cities Lab Global Singapore-ETH CentreSingapore 138602 Department of Building Civil and Environmental Engineering at Concordia UniversityMontrealQuebecCanada Department of Mechanical Engineering The University of Hong KongPok-fu-lam RoadHong KongChina Department of Civil Engineering Chongqing UniversityChongqingChina School of Atmospheric Sciences Sun Yat-sen UniversityZhuhaiChina

A numerical physio-chemical model of the NO_(x)-O_(3) photochemical cycle in the near-wake region of an isolated residential/office building has been presented in this *** investigation delves into the dispersion of reactive air pollutants through the lens of fluid phenomenology and its impact on chemical reactivity,formation,transport,deposition,and *** fluid dynamics(CFD)simulations were conducted for the ground-point-source(GES)and roof-pointsource(RES)*** show that the Damköhler number(Da),which quantifies pollutants’physio-chemical timescales,displays a strong inverse proportionality with the magnitude and spread of NO–increasing Da reduces human exposure to the toxic NO and NO_(2) *** different wind directions were considered,the dispersion range of NO exhibited varying shrinking directions as Da ***,as Da increases,the concentration ratio KNO_(2)/KNO_(x),which quantifies the production of NO_(2) resulting from NO depletion,forms sharp high-low gradients near emission *** GES,the dispersion pattern is governed by the fluid’s phenomenological *** RES,the intoxicated area emanates from the building’s leading-edge,with the lack of shielding inhibiting pollutant interactions in the near-wake,resulting in scant physio-chemical *** NO_(2)/NO_(x) distribution follows a self-similar,stratified pattern,exhibiting consistent layering gradients and attributing to the natural deposition of the already-reacted pollutants rather than in-situ *** the end,building design guidelines have been proposed to reduce pedestrian and resident exposure to NO_(x)-O_(3).

关键词： reactive pollutant dispersion NO_(x)-O_(3)cycle air pollution isolated building physio-chemical modelling

基于多维时空层递的交通信号分布式强化学习方法

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中国公路学报 2024年第7期37卷 250-263页

作者：王福建范诚睿周斌封春房马东方浙江大学建筑工程学院浙江杭州310058 浙江大学工程师学院浙江杭州310015 公安部交通管理科学研究所江苏无锡214151 浙江大学海洋学院浙江舟山316021

信号控制是智能交通系统的重要组成部分,融合人工智能等新技术的信号优化逐渐成为研究热点,具体策略可分为集中式和分布式2类。分布式控制的轻量化状态空间可以有效避免深度强化学习中的维度灾难问题,近年来愈发受到研究者关注。现有的... 详细信息

信号控制是智能交通系统的重要组成部分,融合人工智能等新技术的信号优化逐渐成为研究热点,具体策略可分为集中式和分布式2类。分布式控制的轻量化状态空间可以有效避免深度强化学习中的维度灾难问题,近年来愈发受到研究者关注。现有的分布式协同控制策略多以图卷积网络或图注意力网络为基础挖掘路口的耦合关系,但对路口状态之间的时空关联性随时变交通流的动态变化特征考虑不足。为此,首先基于门控循环神经网络建立时变交通流特征的提取方法,确定多路口时空关联度;其次采用图注意力机制搭建区域时空特征的层递融合算法,以路口重要度为指标实现状态空间重构;再次,采用全连接理念面向自适应相位相序结构构造路口通行权切换决策模型。最后,基于实际路网仿真测试了模型控制效果。结果表明:相比于传统分布式强化学习算法,该模型在低、中、高3种流量下的车辆平均排队长度分别降低了13.74%、5.03%、6.30%以上,表明了新方法的潜在应用价值。

关键词：交通工程智能交通深度强化学习信号控制多角度时空学习层递学习

Surface finish of micro punch with ion beam irradiation

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Transactions of Nonferrous Metals Society of China 2009年第S02期19卷 526-530页

作者： XU Jie WANG chun-ju GUO Bin SHAN De-bin y.SUGIyAMA S.ONO School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Micro-Systems and Micro-Structures Manufacturing Ministry of EducationHarbin Institute of TechnologyHarbin 150080China Elionix Inc. Tokyo 192-0063Japan

Ion beam irradiation was adopted for surface treatment of the micro punch manufactured by precision *** plasma was used for the ion irradiation process,which was generated by the electron cyclotron resonance(ECR)*** surface finish processes of micro punch were carried out at irradiation angles of 45°and 10°,*** surface roughness and topography were measured to estimate the quality of surface *** results show that the ion irradiation is very effective to reduce the surface roughness,which can be improved more significantly at irradiation angle of 10°than at 45°.The technology of surface finish with ion beam irradiation is suitable for the surface treatment of micro die.

关键词： surface finish ion beam micro punch surface roughness

A Criterion for Elliptic Curves with Second Lowest 2-Power in L(1)(Ⅱ)

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Acta Mathematica Sinica,English Series 2005年第5期21卷 961-976页

作者： chun Lai ZHAO LMAM School of Mathematical Sciences Peking University Beijing 100871 P. R. China

Let D = p1p2 …pm, where p1,p2, ……,pm are distinct rational primes with p1 ≡p2 ≡3（mod 8）, pi =1（mod 8）（3 ≤ i ≤ m）, and m is any positive integer. In this paper, we give a simple combinatorial criterion for the value of the complex L-function of the congruent elliptic curve ED2 ： y^2 = x^3- D^2x at s = 1, divided by the period ω defined below, to be exactly divisible by 2^2m-2, the second lowest 2-power with respect to the number of the Gaussian prime factors of D. As a corollary, we obtain a new series of non-congruent numbers whose prime factors can be arbitrarily many. Our result is in accord with the predictions of the conjecture of Birch and Swinnerton-Dyer.

关键词： Elliptic curve L-function Congruent number BSD conjecture

Interleukin-1 and estrogen protect against disseminating dentoalveolar infections

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International Journal of Oral Science 2017年第1期9卷 16-23页

作者： hesham youssef philip stashenko host-microbiome center department of applied oral sciencesthe forsyth instituteCambridgeUSA

Dentoalveolar bacterial infections cause localized tissue and bone destruction, but usually remain well-localized within teeth in immunocompetent hosts. However, in certain cases these infections may invade head and neck tissues, resulting in orofacial abscesses, cellulitis and sepsis, with resultant high morbidity and even mortality. In the present studies, we developed a novel model of spreading dentoalveolar infections in mice by treatment with neutralizing antibodies against both interleukin-la （IL-1a） and IL-1β. Surprisingly male but not female mice given anti-lL-1 antibodies developed orofacial abscesses, weight loss, splenomegaly and sepsis. Female mice developed abscesses and sepsis comparable to males following ovariectomy （OVX）, which was reversed by estrogen supplementation. Anti-lL-1 blockade inhibited IL-12, interferon y （IFNy） and IL-6 but not IL-IO expression in infrabony lesions, suggestive of a local anti-inflammatory response. There was greater infiltration of neutrophils and other inflammatory ceils into lesions in anti-lL-l-treated animals; however, blood leukocytes had reduced bacterial phagocytic and killing activity ex vivo. Estrogen directly stimulated IL-1 production by macrophages, suggesting that the resistance of females to disseminating dentoalveolar infections may be due to their heightened pro-inflammatory responses following bacterial challenge, leading to enhanced localization of these infections.

关键词： cytokines dentoalveolar disseminating infections estrogen neutrophils

Expression and reconstitution of the bioluminescent Ca2+reporter aequorin in human embryonic stem cells,and exploration of the presence of functional IP3 and ryanodine receptors during the early stages of their differentiation into cardiomyocytes

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Science China(Life Sciences) 2016年第8期59卷 811-824页

作者： Harvey y.S.Chan Man chun Cheung yi Gao Andrew L.Miller Sarah E.Webb Division of Life Science&State Key Laboratory of Molecular Neuroscience HKUSTClear Water BayHong KongChina Stem Cell&Regenerative Medicine Consortium Li Ka Shing Faculty of MedicineThe University of Hong KongPokfulamHong KongChina Marine Biological Laboratory Woods Hole MA 02543USA

In order to develop a novel method of visualizing possible Ca2＋ signaling during the early differentiation of hESCs into cardi- omyocytes and avoid some of the inherent problems associated with using fluorescent reporters, we expressed the biolumines- cent Ca2＋ reporter, apo-aequorin, in HES2 cells and then reconstituted active holo-aequorin by incubation withf-coelenterazine. The temporal nature of the Ca2＋ signals generated by the holo-f-aequorin-expressing HES2 cells during the earliest stages of differentiation into cardiomyocytes was then investigated. Our data show that no endogenous Ca2＋ transients （generated by re- lease from intracellular stores） were detected in 1-12-day-old cardiospheres but transients were generated in cardiospheres following stimulation with KC1 or CaC12, indicating that holo-f-aequorin was functional in these cells. Furthermore, following the addition of exogenous ATP, an inositol trisphosphate receptor （IP3R） agonist, small Ca2＋transients were generated from day 1 onward. That ATP was inducing Ca2＋ release from functional IP3Rs was demonstrated by treatment with 2-APB, a known IP3R antagonist. In contrast, following treatment with caffeine, a ryanodine receptor （RyR） agonist, a minima/Ca2＋ response was observed at day 8 of differentiation only. Thus, our data indicate that unlike RyRs, IP3Rs are present and continually functional at these early stages of cardiomyocyte differentiation.

关键词： Ca2+ signaling apo-aequorin expression bioluminescence HES2 human embryonic stem cells hESC-derived cardiospheres IP3 and ryanodine receptors

Demonstration of Inverse Scattering Transform in G-L-M Formalism for NLS Equation in Normal Dispersion with Non-vanishing Boundary

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Communications in Theoretical Physics 2008年第12期50卷 1375-1380页

作者： yANG chun-Nuan HE Jin-chun HUANG Nian-Ning Department of Mathematics Huazhong University of Science and Technology Wuhan 430074 China Department of Physics Wuhan University Wuhan 430072 China

Using the integral representation of the Jost solution,we deduce some conditions as the kernel functionN(x,y,t)if the Jost solution satisfies the two Lax *** we verify the multi-soliton solution of NLS equationwith non-vanishing boundary conditions if we prove that these conditions can be demonstrated by the GLM equation,which determines the kernel function N(x,y,t)in according to the inverse scattering method.

关键词： NLS^+ equation inverse scattering method Gel'fand Levitan Marchenko equation