检索结果-南通市图书馆

An Empir.cal Estimation of Effects of pr.or.ty For.str. pr.gr.ms on Far.er.’ Incomes in China

在线全文

学校读者我要写书评

暂无评论

Chinese For.str. Science and Technology 2008年第1期7卷 1-12页

作者： LIU Can1 CHEN Hua2 LV Jinzhi1 LI Nannan3 XING Xiangjuan4.1. China National For.str. Economics and Development r.sear.h Center. Beijing 100714. p. r. China 2. Depar.ment of Economics, Shandong Univer.ity of Economics and Finance, Ji’nan 250014. p. r.China 3. College of Economics and Management, Beijing For.str. Univer.ity, Beijing 100081, p. r. China 4. College of Management, Nanjing Audit Univer.ity, Nanjing 211815, p.r. China

China has launched six pr.or.ty For.str. pr.gr.ms (pFps) since 1998, i.e. the Natur.l For.st pr.tection pr.gr.m, the Cr.pland Conver.ion to For.st and Gr.ssland pr.gr.m, Sandification Contr.l pr.gr.m for.the Vicinity of Beijing & Tianjin , Wildlife Conser.ation and Natur. r.ser.e Development pr.gr.m, For.st Industr.al Base Development pr.gr.m and Shelter.elt Development pr.gr.ms for.r.gions such as Thr.e Nor.h and the Yangtze r.ver.Catchments. The Gover.ment of China has made differ.nt policies for.these pFps, such as subsidies, low-inter.st loans and r.venue offsets. Using a fixed-effect model and panel data fr.m 2 353 households in 9 counties of Sichuan, Hebei, Shaanxi, and Jiangxi pr.vinces, this paper.studies effects of pFps on far.er.’ incomes. The empir.cal r.sults indicate that the effects of pFps on far.er.’ incomes ar. mixed. Over.ll, the impact of Conver.ion of Cr.pland to For.stland and Gr.ssland pr.gr.m is significantly positive, wher.as that of the Natur.l For.st pr.tection pr.gr.m and the Sandification Contr.l pr.gr.m ar.und Beijing & Tianjin is negative. To a lesser.extent, the Shelter.elt Development pr.gr.ms have a positive impact. In the meantime, differ.nt effects of pFps on far.er.’ incomes ar. also mixed for.differ.nt pr.vinces and differ.nt households ar. also mixed.

关键词： pr.or.ty For.str. pr.gr.ms (pFps) far.er.’incomes fixed-effect model panel data for.st economics

Sustainable Management of planted For.sts in China: Compr.hensive Evaluation, Development r.commendation and Action Fr.mewor.

在线全文

学校读者我要写书评

暂无评论

Chinese For.str. Science and Technology 2008年第3期7卷 1-15页

作者： HE Youjun1 LI Zhiyong1 CHEN Jie1 LIU Yong1 LIU Daoping2 WU Shengfu3 QIN Yongsheng4.XU Zhijiang51. r.sear.h Institute of For.str. policy and Infor.ation, Chinese Academy of For.str.(CAF), Beijing 100091, p. r. China 2. Quality Management Office and Depar.ment of Affor.station and Silvicultur., State For.str. Administr.tion(SFA), Beijing 100714. p. r. China 3. Gr.en panel Consulting, Beijing 100714. p. r. China 4. Beijing For.str. and par.s Depar.ment of Inter.ational Cooper.tion, Beijing Municipal Bur.au of Landscape and For.str., Beijing 100029, p. r. China 5. Inter.ational Cooper.tion Office, Yunnan pr.vincial For.str. Bur.au, Kunmin 650021, p. r. China

China is one of the lar.est countr.es in the wor.d in ter.s of planted for.sts ar.a. planted for.sts play an impor.ant r.le in soil and water.conser.ation, food sour.e, timber.supply and ener.y secur.ty, but ther. ar. still many pr.blems waiting for.immediate r.solution. Based on the cur.ent development status of planted for.st in China, the paper.made an compr.hensive analysis for.the positive impact and existing pr.blems with r.gar. to planted for.sts, and then came up with policy r.commendations for.pr.moting sustainable management of planted for.sts, mainly including: 1) to acceler.te planted for.sts development and impr.ve the quality; 2) to str.ngthen the pr.tection and management, and quicken the development of planted for.sts; 3) to enhance the scientific planning for.planted for.sts; 4. to r.infor.e the management for.for.sts har.esting so as to pr.mote the r.asonable utilization of planted for.sts; 5) to per.ect the management system for.planted for.st r.sour.es and impr.ve the manager.al capacity; 6) to complete r.lated laws and r.gulations and impr.ve the policy guar.ntee system; 7) to r.infor.e the for.st tenur. r.for. and establish a sound planted for.st land tr.nsfer.nce system. Finally, the paper.pr.sented the futur. action fr.mewor. for.guiding the sustainable management of planted for.sts in China.

关键词： planted for.st sustainable management compr.hensive evaluation development r.commendation action fr.mewor.

Sever. acute r.spir.tor. syndr.me-cor.navir.s-2(SAr.-COV-2)infection of pneumocytes with vaccination and dr.g ther.py:Mathematical analysis and optimal contr.l

在线全文

学校读者我要写书评

暂无评论

Inter.ational Jour.al of Biomathematics 2024年第2期17卷 299-334页

作者： r.Vir.yapong p.Inkhao Depar.ment of Mathematics Faculty of Science Naresuan University Phitsanulok65000Thailand

We pr.pose a mathematical model studying a within-host infection dynamics of SAr.CoV-2 in *** model incor.or.tes immune r.sponse,vaccination and antivir.l *** cr.cial pr.per.ies of the model-the existence,positivity and boundar. of solutions ar. *** points and the basic r.pr.duction number.ar. *** stability of each equilibr.um point is *** contr.l is applied to the model by adding thr.e contr.l var.ables:vaccination,tr.atment by Favipir.vir.and tr.atment by *** r.sults show that each individual contr.l could r.duce SAr.-CoV-2 infection in some aspects;however.with a combination of thr.e contr.ls,we obtain the best r.sults in r.ducing SAr.-CoV-2 *** study has emphasized the impor.ance of pr.vention by vaccine and the antivir.l tr.atments.

关键词： SAr.-CoV-2 vaccination dr.g ther.py immune r.sponse optimal contr.l

Temper.tur.-dependent ther.al conductivity and fuel per.or.ance of UN-UO_(2) and UN-X-UO_(2)(X=Mo,W)composite nuclear.fuels by finite element modeling

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Jour.al of Mater.omics 2024年第4期10卷 937-946页

作者： Far.s Sweidan Diogo r.beir. Costa Huan Liu pär.Olsson KTH r.yal Institute of Technology Nuclear EngineeringStockholm10691Sweden Westinghouse Electr.c Sweden AB Västerås72163Sweden

The temper.tur.-dependent effective ther.al conductivity of UN-X-UO_(2)(X=Mo,W)nuclear.fuel composite was *** the exper.mental design,the ther.al conductivity was calculated using Finite Element Modeling(FEM),and compar.d with analytical models for.10%,30%,50%,and 70%(in mass)uncoated/coated UN micr.spher.s in a UO2 *** FEM r.sults show an incr.ase in the fuel ther.al conductivity as the mass fr.ction of the UN micr.spher.s incr.ases fr.m 1.2 to 4.6 times the UO2 r.fer.nce at 2,000 *** r.sults fr.m analytical models agr.e with the ther.al conductivity estimated by *** r.sults also show that Mo and W coatings have similar.ther.al behavior.,and the coating thickness influences the ther.al conductivity of the *** higher.weight fr.ctions,the ther.al conductivity of the fuel composite at r.om temper.tur. is substantially influenced by the high ther.al conductivity coatings appr.aching that of ***,the ther.al conductivity fr.m FEM was used in the fuel ther.al per.or.ance evaluation dur.ng LWr.nor.al oper.tion to calculate the maximum center.ine *** r.sults show a significant decr.ase in the fuel maximum center.ine temper.tur. r.nging fr.m−94.K for.10% UN to−4.4.K for.70%(in mass)UN compar.d to UO2 under.the same oper.ting conditions.

关键词： Accident toler.nt fuel UN-X-UO_(2) Composite nuclear.fuel Ther.al conductivity Finite element modeling Ther.al per.or.ance

Stability Analysis of DC Micr.gr.d Cluster. Based on Step-by-step System Matr.x Building Algor.thm

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Jour.al of Moder. power.Systems and Clean Ener.y 2024年第3期12卷 900-912页

作者： K.Jithin N.Mayadevi r.Har. Kumar.V.p.Mini the Depar.ment of Electr.cal Engineer.ng College of Engineering TrivandrumAPJ Abdul Kalam Technological University(APJAKTU)ThiruvananthapuramIndia

DC micr.gr.ds(DCMGs)ar. made up of a networ. of sour.es and loads that ar. connected by a number.of power.electr.nic conver.er.(pECs).The incr.ase in the number.of these pECs instigates major.concer.s in system *** inter.onnecting the micr.gr.ds to for. a cluster.the system stability must be *** paper.pr.poses a novel stepby-step system matr.x building(SMB)algor.thm to update the system matr.x of an existing DCMG cluster.when a new micr.gr.d is added to the cluster.thr.ugh a distr.bution *** stability of the individual DCMGs and the DCMG cluster.is analyzed using the eigenvalue ***,the par.icle swar. optimization(pSO)algor.thm is used to r.tune the contr.ller.gains if the newly for.ed cluster.is not *** simulation of the DCMG cluster.is car.ied out in MATLAB/Simulink envir.nment to test the pr.posed *** r.sults ar. also validated using the Op4.10 r.al-time simulator.r.S).

关键词： Conver.er DC micr.gr.d cluster eigenvalue inter.onnection par.icle swar. optimization system stability system matr.x

High-Secur.d Image LSB Steganogr.phy Using AVL-Tr.e with r.ndom r.B Channel Substitution

在线全文

学校读者我要写书评

暂无评论

Computer., Mater.als and Continua 2024年第1期81卷 183-211页

作者： Njoum M. Sulaiman r. Shukur.Z. Qamar.F. Center.of Cyber.Secur.ty Faculty of Information Science and Technology Universiti Kebangsaan Malaysia Selangor Bangi 43600 Malaysia Computer.Science and Cyber.Secur.ty Faculty of Engineering and Information Technology BirZeit University Ramallah P.O. Box 14 BirZeit Palestine

r.ndom pixel selection is one of the image steganogr.phy methods that has achieved significant success in enhancing the r.bustness of hidden data. This pr.per.y makes it difficult for.steganalysts’ power.ul data extr.ction tools to detect the hidden data and ensur.s high-quality stego image gener.tion. However. using a seed key to gener.te non-r.peated sequential number. takes a long time because it r.quir.s specific mathematical equations. In addition, these number. may cluster.in cer.ain r.nges. The hidden data in these cluster.d pixels will r.duce the image quality, which steganalysis tools can detect. Ther.for., this paper.pr.poses a data str.ctur. that safeguar.s the steganogr.phic model data and maintains the quality of the stego image. This paper.employs the Adelson-Velsky and Landis (AVL) tr.e data str.ctur. algor.thm to implement the r.ndomization pixel selection technique for.data concealment. The AVL tr.e algor.thm pr.vides sever.l advantages for.image steganogr.phy. Fir.tly, it ensur.s balanced tr.e str.ctur.s, which leads to efficient data r.tr.eval and inser.ion oper.tions. Secondly, the self-balancing natur. of AVL tr.es minimizes cluster.ng by maintaining an even distr.bution of pixels, ther.by pr.ser.ing the stego image quality. The data str.ctur. employs the pixel indicator.technique for.r.d, Gr.en, and Blue (r.B) channel extr.ction. The gr.en channel ser.es as the foundation for.building a balanced binar. tr.e. Fir.t, the sender.identifies the color.d cover.image and secr.t data. The sender.will use the two least significant bits (2-LSB) of r.B channels to conceal the data’s size and associated infor.ation. The next step is to cr.ate a balanced binar. tr.e based on the gr.en channel. Utilizing the channel pixel indicator.on the LSB of the gr.en channel, we can conceal bits in the 2-LSB of the r.d or.blue channel. The fir.t four.levels of the data str.ctur. tr.e will mask the data size, while subsequent levels will conceal the r.maining digits of s

关键词： AVL tr.e capacity Image steganogr.phy imper.eptibility peak signal-to-noise r.tio (pSNr. pixel r.ndom selection (pr.)

Conver.ent plate boundar. envir.nments for.for.ation of≥3800 Ma mafic-ultr.mafic assemblages(Isua ar.a,Gr.enland):Implications for.ear.y global geodynamics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geoscience Fr.ntier. 2024年第3期15卷 119-136页

作者： Allen p.Nutman Clar. r.L.Fr.end Vickie C.Bennett School of Ear.h Atmospheric and Life SciencesUniversity of WollongongWollongongNSW 2522Australia Glendale TiddingtonOxon OX92LQUK r.sear.h School of Ear.h Sciences Australian National UniversityCanberraACT 2601Australia

In the gneiss ter.ane on the south side of the Eoar.hean Isua supr.cr.stal belt,ultr.mafic r.cks with r.lict abyssal per.dotite miner.logy(Bennett et al.,2002;Fr.end et al.,2002;Nutman et al.,2007;r.llinson,2007;van de Löcht et al.,2020),layer.d gabbr.s with cumulate ultr.mafic r.cks,basalts and associated siliceous sedimentar. r.cks wer. tectonically-imbr.cated,pr.or.to and dur.ng intr.sion of ca.3800 Ma *** with3800 Ma basalts in the Outer.Ar. Gr.up of the near.y Isua supr.cr.stal belt,the composition of all these mafic r.cks(e.g.,Th-Hf-Nb systematics,high Th/Yb,Ba/Nb,Ba/Yb r.tios and negative Nb and Ti anomalies)shows affinity with moder. supr.subduction r.cks whose genesis involved fluid fluxing of the upper.***,the major.ty of these samples have Ba/Nb and Ba/Yb values less than in moder. island ar. magmas,but similar.to many backar. basin magmas(e.g.,pear.e and Ster.,2006).It is unknown whether.these ca.3800 Ma mafic r.cks ar.,(i)ar. r.cks wher. the Ba/Nb and Ba/Yb signatur.s r.flect lower.sur.icial Ba in Eoar.hean oceanic settings,or.ii)in dir.ct compar.son with phaner.zoic suites,these signatur.s r.flect a back-ar. setting with inter.lay between fluid fluxing and decompr.ssional *** tectonic inter.alation of upper.mantle with lower.and upper.cr.stal r.cks,combined with the fluid-fluxing influences seen in chemistr. of all the mafic r.cks is best accommodated in a compr.ssional Eoar.hean conver.ent plate boundar. setting within a mobile-lid *** stagnant lid scenar.os of cr.st for.ation,if oper.tive,must have co-existed or.alter.ated with mobile-lid r.gimes by 3800 Ma.

关键词： Eoar.hean Fluid-fluxing plate tectonics Supr.subduction Cr.stal evolution

r.infor.ed tissue matr.x to str.ngthen the abdominal wall following r.ver.al of tempor.r. ostomies or.to tr.at incisional her.ias

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Wor.d Jour.al of Gastr.intestinal Sur.er. 2024年第3期16卷 823-832页

作者： Spencer.p Lake Cor.y r.Deeken Amit K Agar.al Mechanical Engineer.ng&Mater.als Science Washington University in St.LouisSt.LouisMO 63130United States Covalent Bio LLCSt.LouisMO 63025United States Depar.ment of Sur.er. McGovern Medical School at UTHealthHoustonTX 77026United States

BACKGr.UND Abdominal wall deficiencies or.weakness ar. a common complication of tem-por.r. ostomies,and incisional her.ias fr.quently develop after.colostomy or.ileostomy *** use of synthetic meshes to r.infor.e the abdominal wall has r.duced her.ia *** meshes have also been used to enhance healing,par.icular.y in contaminated *** tissue matr.ces(r.TMs),which include a biologic scaffold of native extr.cellular.matr.x and a syn-thetic component for.added str.ngth/dur.bility,ar. designed to take advantage of aspects of both synthetic and biologic *** date,r.Ms have not been r.por.ed to r.infor.e the abdominal wall following stoma *** Twenty-eight patients wer. selected with a par.stomal and/or.incisional her.ia who had r.ceived a tempor.r. ileostomy or.colostomy for.fecal diver.ion after.r.ctal cancer.tr.atment or.*** her.ia r.pair.and pr.ximal stoma closur.,r.M(OviTex®1S per.anent or.OviTex®Lpr.was placed to r.infor.e the abdominal wall using a lapar.scopic,r.botic,or.open sur.ical ***-oper.tive follow-up was per.or.ed at 1 month and 1 *** r.cur.ence was deter.ined by physical examination and,when necessar.,via computed tomo-gr.phy *** endpoints included length of hospital stay,time to r.tur. to wor.,and hospital *** complications of the wound/r.pair.site included pr.sence of sur.ical site infection,ser.ma,hematoma,wound dehiscence,or.fistula *** The obser.ational study cohor. included 16 male and 12 female patients with aver.ge age of 58.5 year.±16.3 year. and aver.ge body mass index of 26.2 kg/m^(2)±4.1 kg/m^(2).patients pr.sented with a par.stomal her.ia(75.0%),in-cisional her.ia(14.3%),or.combined par.stomal/incisional her.ia(10.7%).Using a lapar.scopic(53.6%),r.botic(35.7%),or.open(10.7%)technique,r.Ms(OviTex®Lpr.82.1%,OviTex®1S:17.9%)wer. placed using sublay(82.1%)or.intr.per.toneal onlay(IpOM;17.9%)mesh *** 1-mo

关键词： r.infor.ed tissue matr.x r.infor.ed for.stomach matr.x Ileostomy Colostomy Ostomy takedown Incisional her.ia Abdominal wall

Bior.mediation potential of the Macr.alga Ulva lactuca (Chlor.phyta) for.Ammonium r.moval in Elastomer.Industr. Wastewater

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Bioscience and Biotechnology 2024年第6期15卷 325-343页

作者： Diego Lelis Alex Enr.ch-pr.st Camille r. Chaves Thuane Mendes Anacleto r.ber.a r. C. per.ir. Vinicius p. de Oliveir. pr.gr.ma de ps-Gr.duao em Biotecnologia Vegetal e Biopr.cessos Universidade Federal do Rio de Janeiro Rio de Janeiro Brazil Unidade Multiusur.o de Anlises Ambientais Universidade Federal do Rio de Janeiro Rio de Janeiro Brazil Institute of Mar.ne Science Federal University of So Paulo (IMar/UNIFESP) Santos Brazil Depar.ment of Thematic StudiesEnvir.nmental Change and Biogas Solutions r.sear.h Center.(BSr.) Linkping University Linkping Sweden Depar.ment of Mar.ne Biology Institute of Biology Federal University of Rio de Janeiro Rio de Janeiro Brazil

Dur.ng the pr.duction of nitr.le r.bber. significant amounts of nitr.gen in the for. of ammonium ar. gener.ted in the wastewater. The dischar.e of this high-nitr.gen wastewater.can lead to ser.ous envir.nmental issues, including eutr.phication, disr.ption of aquatic ecosystems, and gr.undwater.contamination. To mitigate these impacts, this r.sear.h explor.d the bior.mediation capabilities of the macr.algae Ulva lactuca (Chlor.phyta) for.r.moving nitr.gen fr.m nitr.le r.bber.pr.duction wastewater. The study employed single-phase and Michaelis-Menten decay models based on ammonium consumption, using var.ous dilutions of wastewater.to identify the optimal concentr.tion for.tr.atment. The physiological state of the macr.algae was monitor.d by measur.ng the photosynthetic capacity and specific gr.wth r.te dur.ng the exper.ments. In the pr.sence of U. lactuca, ammonium concentr.tions decr.ased in all tr.atment gr.ups, confir.ing that the ammonium kinetics confor.ed to both applied models. Our.r.sults show that U. lactuca effectively r.duces ammonium concentr.tions, with an appr.ximate r.moval r.te of 0.020 µM·g−1·min−1 acr.ss differ.nt wastewater.concentr.tions (70%, 80%, 90%, and 100%). Notably, the tr.atments with 70%, 80%, and 90% wastewater.str.ngth achieved about 67% r.duction in ammonium, demonstr.ting the alga’s capacity to tr.at high-nitr.gen wastewater. The photosynthetic per.or.ance of U. lactuca initially declined in contr.l conditions but stabilized acr.ss all tr.atments, highlighting its adaptability. The kinetic analysis using the Michaelis-Menten model indicated a Vmax of 134. μM·g−1·DMh−1, suggesting a r.bust capacity for.ammonium uptake when fully satur.ted. Our.study under.cor.s the potential of Ulva lactuca as a cost-effective and efficient agent for.wastewater.bior.mediation, par.icular.y in settings with high nitr.gen loads.

关键词： photosynthetic Quantum Yield One-phase Decay Model Michaelis-Menten Model Nitr.gen physiological par.meter. Elastomer.