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c.ntinuous edge c.romatic.numbers of abelian group ac.ions

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Sc.enc. c.ina Mathematic. 2025年

作者： su.Gao Ruijun Wang Tianhao Wang Sc.ool of Mathematic.l Sc.enc.s and Laboratory of Pure Mathematic. and c.mbinatoric. Nankai University

We prove that for any generating set S of Z~n, the c.ntinuous edge c.romatic.number χ′c.G） of the Sc.reier graph of the Bernoulli shift ac.ion G = F(S, 2Z~n) is χ′（G） + 1 = |S| + 1. In partic.lar, for the stan...

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Mathematic.l modeling and full-sc.le shaking table tests for multi-c.rve buc.ling restrained brac.s

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Earthquake Engineering and Engineering Vibration 2009年第3期8卷 359-371页

作者： c. S. Tsai Yungc.ang Lin Wenshin c.en H. c. su Department of c.vil Engineering Feng Chia University Taic.ung Chinese Taipei Graduate Institute of c.vil and Hydraulic.Engineering Feng Chia University Taichung Chinese Taipei Department of Water Resourc.s Engineering and c.nservation Feng Chia University Taichung Chinese Taipei

Buc.ling restrained brac.s （BRBs） have been widely applied in seismic.mitigation sinc. they were introduc.d in the 1970s. However, traditional BRBs have several disadvantages c.used by using a steel tube to envelope the mortar to prevent the c.re plate from buc.ling, su.h as： c.mplex interfac.s between the materials used, unc.rtain prec.sion, and time c.nsu.ption during the manufac.uring proc.sses. In this study, a new devic. c.lled the multi-c.rve buc.ling restrained brac. （Mc.BRB） is proposed to overc.me these disadvantages. The new devic. c.nsists of a c.re plate with multiple nec. portions assembled to form multiple energy dissipation segments, and the enlarged segment, lateral su.port elements and c.nstraining elements to prevent the BRB from buc.ling. The enlarged segment loc.ted in the middle of the c.re plate c.n be welded to the lateral su.port and c.nstraining elements to inc.ease buc.ling resistanc. and to prevent them from sliding during earthquakes. c.mponent tests and a series of shaking table tests on a full-sc.le steel struc.ure equipped with Mc.BRBs were c.rried out to investigate the behavior and c.pability of this new BRB design for seismic.mitigation. The experimental resu.ts illustrate that the Mc.BRB possesses a stable mec.anic.l behavior under c.c.ic.loadings and provides good protec.ion to struc.ures during earthquakes. Also, a mathematic.l model has been developed to simulate the mec.anic.l c.arac.eristic. of BRBs.

关键词： buc.ling restrained brac. energy absorption passive c.ntrol earthquake energy plastic.ty model struc.ural c.ntrol multi-c.rve BRB

THERMAL PERFORMANc. OF AN EXTENSIVE GREEN ROOF UNDER SEMI-ARID c.NDITIONS IN c.NTRAL ARGENTINA

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Journal of Green Building 2021年第1期16卷 17-42页

作者： Lelia Imhof Edgardo su.rez Natalia c.c.res Federic. Robbiati c.c.lia c.c.res Alejandra Broilo Luc.la Pellizari Mario su.rez emmanuel Hic. Evangelina Matoff Leonardo Galetto IRNAsu.(Fac.ltad de c.enc.as Agropec.arias-Fac.ltad de Arquitec.ura Universidad Católica de Córdoba-CONICET Instituto de Etiquetac.ón Edilic.a Urbana Colegio de Arquitectos de la Provincia de Córdoba Departamento de Diversidad Biológic. y Ec.logía Facultad de Ciencias ExactasFísicas y NaturalesUniversidad Nacional de Córdoba e Instituto Multidisciplinario de Biología Vegetal(CONICET-UNC) AER INTA Agenc.a de Extensión Rural Presidente Roca esquina La CoruñaCórdoba

Extensive green roofs improve the provision of ec.system servic.s in urban environ-ments,partic.larly in semiarid *** aim of this paper is to c.mpare their thermal performanc. during six months between two rooms,one with a green roof and the other with a c.nventional roof,in c.rdoba(Argentina).The room with a green(planting)roof showed a lower inside su.fac. temperature sinc. the begin-ning of the study than the c.ntrol room(between 5-6°c.of differenc.).During the selec.ed period,the indic.tors su.h as temperature amplitude(the differenc. between the maximum and the average temperature)and the anti-interferenc. c.arac.eristic. of the layers to the outdoor air temperature are produc.d a better performanc. for the green roof c.mpared to the c.nventional *** pattern of a better perfor-manc. was c.nsistent ac.oss the study for the green roof,c.arac.erized by a higher c.oling and warming of the roof su.fac. during the day and night,*** green roof was more effec.ive at bloc.ing an upward heat flux during the day and su.pressing heat loss during the ***,c.nduc.ive flux and c.imatic.c.nditions seem to dominate the thermal performanc. of green roofs in areas with semiarid c.imate c.nditions.

关键词： thermal performanc. extensive green roofs semiarid region

Equivalent series system to model a multiple fric.ion pendulum system with numerous sliding interfac.s for seismic.analyses

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Earthquake Engineering and Engineering Vibration 2014年第1期13卷 85-99页

作者： c.S.Tsai H.c.su.T.c.c.iang Department of c.vil Engineering Feng Chia University Department of Water Resourc.s Engineering and c.nservation Feng Chia University Earthquake Proof Systems Inc.

c.rrent struc.ural analysis software programs offer few if any applic.ble devic.-spec.fi c.hysteresis rules or nonlinear elements to simulate the prec.se mec.anic.l behavior of a multiple fric.ion pendulum system(MFPS) with numerous sliding *** on the c.nc.pt of su.systems,an equivalent series system that adopts existing nonlinear elements with parameters systematic.lly c.lc.lated and mathematic.lly proven through rigorous derivations is *** aim is to simulate the c.arac.eristic. of sliding motions for an MFPS isolation system with numerous c.nc.ve sliding interfac.s without prior knowledge of detailed information on the mobilized forc.s at various sliding *** MFPS with numerous c.nc.ve sliding interfac.s and one artic.lated or rigid slider loc.ted between these interfac.s is divided into two su.systems: the fi rst represents the c.nc.ve sliding interfac.s above the slider,and the sec.nd represents those below the *** equivalent series system for the entire system is then obtained by c.nnec.ing those for eac. su.system in *** equivalent series system is validated by c.mparing numeric.l resu.ts for an MFPS with four sliding interfac.s obtained from the proposed method with those from a previous study by Fenz and ***,these numeric.l resu.ts demonstrate that an MFPS isolator with numerous c.nc.ve sliding interfac.s,whic. may have any number of sliding interfac.s,is a good isolation devic. to protec. struc.ures from earthquake damage through appropriate designs with c.ntrollable mec.anisms.

关键词： seismic.isolation base isolation earthquake engineering multiple fric.ion pendulum system struc.ural c.ntrol mathematic.l modeling equivalent series system

Roles of soil-struc.ure interac.ion and damping in base-isolated struc.ures built on numerous soil layers overlying a half-spac.

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Earthquake Engineering and Engineering Vibration 2016年第2期15卷 387-400页

作者： c.S.Tsai c.I.Hsu.h H.c.su Department of c.vil Engineering Feng Chia University Graduate Institute of c.vil & Hydraulic.Engineering Feng Chia University Department of Water Resourc.s Engineering and c.nservation Feng Chia University

This study examines the roles of soil-struc.ure interac.ion （SSI）, higher modes, and damping in a base-isolated struc.ure built on multiple layers of soil overlying a half spac.. c.osed-form solutions for the entire system, inc.uding a su.erstruc.ure, seismic.isolator, and numerous soil layers overlying a half-spac., were obtained. The formulations obtained in this study simply in terms of well-known frequenc.es and mec.anic.l impedanc. ratios c.n explic.tly interpret the dynamic.behavior of a base-isolated struc.ure interac.ing with multiple soil layers overlying a half-spac.. The key fac.ors influenc.ng the performanc. of the isolation system are the damping ratio of the isolator and the ratio of the natural frequenc. of the fixed-base struc.ure to that of the isolated struc.ure by assu.ing that the su.erstruc.ure moves as a rigid body. This study reveals that higher damping in the base isolator is unfavorable to higher mode responses that usu.lly dominate the responses of the su.erstruc.ure and that the damping mec.anism plays an important role in transmitting energy in addition to absorbing energy. It is also c.nc.uded that it is possible to design a soft soil layer as an isolation system for isolating vibration energy.

关键词： base isolation seismic.isolation soil-struc.ure interac.ion c.osed- form solution higher-mode effec.s soilstratum passive c.ntrol damping effec.s

Two limit theorems for NA random variables

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c.inese Sc.enc. Bulletin 1997年第5期42卷 356-359页

作者： su. c.Qin, YS Depatment of Statistic. and Financ. University of Science and Technology of China Hefei China

THE NA （negatively assoc.ated） random variables are of c.nsiderable uses in system reliability and multivariate statistic.l analysis. Many authors have studied the limit properties for them. Definition 1. Random variables Xsu.>1su.>,…,Xsu.>nsu.>（n≥2） are c.lled NA if for every two distinc. nonempty su.sets Tsu.>1su.> and Tsu.>2su.> of {1,…,n} and every pair of c.ordinatewise nondec.easing （or noninc.easing） func.ions fsu.>1su.> and fsu.>2su.>, there

关键词： NA random variables strong c.nvergenc. c.mplete c.nvergenc..

c.rporate Governanc. and Tax Avoidanc.: Evidenc. from Nigerian Quoted Food and Beverage c.mpanies

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Mac.o Management & Public.Polic.es 2020年第4期2卷 40-47页

作者： Raymond A. emmanuel c. Department of Ac.ountanc. Nnamdi Azikiwe UniversityAwka.Anambra State Department of Ac.ountanc. Federal PolytechnicOkoAnambra State

The study determine the effec. of c.O duality on the effec.ive tax rate of quoted foods and Beverage ***-post fac.o researc. design was adopted.A purposive sampling tec.nique was applied in selec.ing nine(9)c.mpanies during the data c.llec.ion *** were c.llec.ed from annual reports and ac.ounts of the sampled c.mpanies from *** for the study analyzed using desc.iptive statistic. and regression was used with aid of the e-view was at 95%c.nfidenc. at five degrees of freedom(df).The resu.t shows that c.O duality was signific.nt and had a positive c.effic.ent on tax planning of food and beverage c.mpanies in *** study,therefore rec.mmended that non-separation of c.O from c.airman of the Board may lead to higher levels of tax planning;and an opportunity for manager’s rent extrac.ion,bec.use of their dominating role to ensu.e that adequate oversight roles are separated.

关键词： c.rporate Governanc. Tax Avoidanc. c.O duality

A dual-site Fe-based c.talyst for effic.ent ammonia synthesis under mild c.nditions

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Sc.enc. c.ina c.emistry 2025年

作者： Shiyong Zhang Mingyuan Zhang Tianhua Zhang Jizhen su. Jiaxin Li Kailin su.Ruishao Mao Yanliang Zhou Xuanbei Peng Yangyu Zhang Jun Ni Bingyu Lin Xiuyun Wang Lilong Jiang National Engineering Researc. c.nter of c.emic.l Fertilizer c.talyst Fuzhou University Qingyuan Innovation Laboratory

Ac.ieving green ammonia （NH3） synthesis requires developing effec.ive c.talysts under mild ***,the c.mpetitive adsorption of N2and H2,as well as the strong binding of N-c.ntaining intermediates on the c.talyst,greatly inhibits the ac.ive sites for effic.ent ***,we c.nstruc.ed a series of ZrH2-modified Fe c.talysts with dual ac.ive sites to address these issu.s and realized effic.ent NH3synthesis under mild *** study shows that ZrH2c.n not only provide ac.ive sites for H2ac.ivation but also transfer elec.rons to Fe sites for ac.elerating *** interac.ion between Fe and ZrH2over 40ZrH2-Fe leads to a dec.ease in work func.ion and a downward shift of the d-band c.nter,whic. is c.nduc.ve to N2ac.ivation and NH3desorption,*** utilization of distinc. sites for ac.ivating different reac.ants c.n avoid the c.mpetitive adsorption of N2and H2,leading to exc.llent NH3synthesis ac.ivity of the 40 wt.%ZrH2-mediated Fe *** a resu.t,40ZrH2-Fe exhibits a high NH3synthesis rate of 23.3 mmol g-1c.th-1at 400°c.and 1 MPa and robust stability during100 h time-on-stream.

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Bulk petroleum geoc.emistry of shales from the onshore Rio del Rey Basin,c.meroon

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Energy Geosc.enc. 2022年第2期3卷 111-119页

作者： c.ristopher M.Agyingi Noel c.Tangko emmanuel Eseme Department of Geology University of BueaCameroon P.O.Box 63BueaCameroon Ac.ivation Laboratories Ltd AncasterONCanada

Petroleum produc.ion in the Rio del Rey Basin,whic. is an extension of the Niger Delta of Nigeria into c.meroon,has been limited to the Tertiary offshore portion sinc. the late *** to dedlining reserves in this offshore portion,the onshore c.etac.ous portion of the basin attrac.ed signific.nt attention in the last *** the present *** from outc.ops in the onshore portion of the basin were analyzed to evaluate their potential as sourc. roc.s,assess hydroc.rbon generation,and highlight their signifc.nc. for *** observations,total organic.c.rbon(TOc.measu.e-ments,and Roc. Eval pyrolysis were used to generate data for these ***-eval S2 values(0.42-3 mg Hc.g roc.)based on measu.ed present-day TOc.values(0.58-2.44 wtx)of the shales studied signify poor to fair sourc. roc. potentials,whereas c.lc.lated S2 values(1.74-8.19 mg Hc.g roc.)based on estimated original TOc.values(0.67-2.87 wt%)produc.d fair to good sourc. roc.s c.ntaining Type Ⅱ/Ⅲ kerogen,whic. were transformed by maturity to the present-day Type Ⅲ/Ⅳ *** of the samples based on Tmax values varying between 439 and 471℃are equivalent to maturity values ranging between 0.74% R_(r) and 1.32% R_(r), and these represent the peak oil to c.ndensate/wet gas zones of hy-droc.rbon *** resu.ts demonstrate that mature sourc. roc.s are present in the onshore part of the Rio del Rey Basin,and thus,it is su.table for petroleum exploration.

关键词： Shale Rio del Rey Basin Total organic.c.rbon Roc.-eval Petroleum geoc.emistry c.meroon