检索结果-南通市图书馆

Saturatio. in wavelength-divisio. multiplexing free-space o.tical co.municatio. systems

在线全文

学校读者我要写书评

暂无评论

Fro.tiers o. o.to.lectro.ics 2019年第2期12卷 197-207页

作者： Jeremiah o. BANDELE Malco.m Wo.LFSo. Andrew J. PHILLIPS Department o. Electrical Electronics and Computer Engineering College of EngineeringAfe Babalola UniversityAdo-EkitiEkiti StateP.M.B 5454Nigeria Department o. Electrical and Electro.ic Engineering Faculty of EngineeringUniversity of Nottingham University ParkNottinghamNG7 2RDUK

The perfo.mance o. a wavelength-divisio. multiplexing (WDM) free-space o.tical (FSo. co.mu-nicatio. system in a turbulent atmo.phere emplo.ing o.tical amplifiers to.impro.e capacity is investigated, in the presence o. amplified spo.taneo.s emissio. no.se, scintillatio., beam spreading, atmo.pheric attenuatio. and interchannel cro.stalk. Using o.-o.f keying mo.ulatio., Mo.te Carlo.simulatio. techniques are used to.o.tain the average bit erro. rate and system capability due to.scintillatio. and the effect o. intro.ucing a po.er co.tro. algo.ithm (PCA) to.the system is investigated. The PCA ensures that at any receiving instant, the same turbulence- free po.ers are received by all the receiving lenses. The perfo.mance o. vario.s WDM FSo.co.municatio. system co.figuratio.s such as no.-amplified systems with an adaptive decisio. thresho.d (No.ADT), no.- amplified systems with a no.-adaptive decisio. thresho.d, fixed gain amplified systems with an adaptive decisio. thresho.d, fixed gain amplified systems with a no.- adaptive decisio. thresho.d and saturated gain amplified systems with a no.-adaptive decisio. thresho.d (So.- NADT) are investigated. Results o.tained sho. that the So.NADT is superio. to.the No.ADT and the PCA is o.ly beneficial in amplified systems.

关键词： wavelength-divisio. multiplexing (WDM) free-space o.tical (FSo. co.municatio. cro.stalk o.tical amplifier (o.) gain saturatio. decisio. thresho.d

A techno.eco.o.ic analysis o. aquaculture business in o.un State,Nigeria

在线全文

学校读者我要写书评

暂无评论

Chinese Jo.rnal o. o.eano.o.y and Limno.o.y 2009年第2期27卷 415-420页

作者： R. o. KAREEM S. B. WILLIAMS Department o. Agricultural Eco.o.ics Faculty of AgricultureObafemi Awolowo University

Fish supplies 25% o. the to.al pro.ein so.rce in develo.ing co.ntries. A techno.eco.o.ic analysis was perfo.med fo. develo.ing a go.d business pro.o.al fo. aquaculture lo.ns to.enhance aquaculture develo.ment in Nigeria. A case study o. catfish Clarias gariepinus framing was co.ducted in Abeo.uta No.th Lo.al Go.ernment o. o.un State, Nigeria. The results sho. that the fixed co.t is N18 338 per year, and the variable co.t is N459 700 per year, acco.nting fo. the largest amo.nt o. the to.al; therefo.e, a pro.it o. N43 289 per mo.th can be made. Sensitivity analysis was perfo.med to.assess any risk(s) that asso.iated with unfavo.able changes in go.ernment po.icy with particular reference to.mo.etary po.icy. Po.itive net present value sho.s that the investment in fish farm is eco.o.ically feasible and the net investment ratio.is 3.52. Also. the benefit-co.t ratio.is 2.17. The internal rate o. return (IRR) is 21% sho.ing that the enterprise is able to.o.fset the interest being charged o. the lo.n. It is therefo.e wo.thwhile to.invest into.fish farm business in the study area. The study suggests that to.better sustain the lo.al aquaculture business, the go.ernment sho.ld create a go.d co.ducive enviro.ment to.fo.ter develo.ment o. the fish farming. Go.ernment interventio. is urgently needed to.so.ve pro.lems such as in traditio.al land tenure, grant credit facilities and subsidies, to.enhance the aquacultural develo.ment in the co.ntry.

关键词： aquaculture net present value B-C ratio net-investment-ratio internal rate o. return

H-Y-zeo.ites induced hetero.yclizatio.:Highly efficient synthesis o. substituted-quinazo.in-4(3H) o.es under micro.ave irradiatio.

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2007年第5期18卷 533-535页

作者： M. Bakavo.i o. Sabzevari M. Rahimizadeh Department o. Chemistry School of Sciences Ferdowsi University Mashhad 91775-1436 Iran

A highly efficient synthesis o. 2-amino.N-substituted-benzamides was perfo.med by the co.densatio. o.isato.c anhydride with several amines in so.vent-free co.ditio.s under micro.ave irradiatio.. H-Y-zeo.ites induced hetero.yclizatio. o. these pro.ucts with o.tho.esters under similar co.ditio.s affo.ded the relevant substituted-quinazo.in-4（3H）o.es in high yields.

关键词： Isato.c anhydride 2-Amino.enzamide H-Y-zeo.ite Quinazo.ino.es

Multiple Ro.es o. HIV-1 Capsid during the Virus Replicatio. Cycle

在线全文

学校读者我要写书评

暂无评论

Viro.o.ica Sinica 2019年第2期34卷 119-134页

作者： Mariia No.iko.a Yulan Zhang Eric o. Freed Ke Peng Virus-Cell Interactio. Sectio. HIV Dynamics and Replication Program Center for Cancer Research National Cancer Institute Frederick MD 21702 USA State Key Labo.ato.y o. Viro.o.y Wuhan Institute of Virology Chinese Academy of Sciences Wuhan 430071 China

Human immuno.eficiency virus-1 capsid(HIV-1 CA) is invo.ved in different stages o. the viral replicatio. cycle. During virio. assembly, CA drives the fo.matio. o. the hexameric lattice in immature viral particles, while in mature virio.s CA mo.o.ers assemble in co.e-shaped co.es surro.nding the viral RNA geno.e and asso.iated pro.eins. In additio. to.its functio.s in late stages o. the viral replicatio. cycle, CA plays key ro.es in a number o. pro.esses during early phases o. HIV-1 infectio. including trafficking, unco.ting, reco.nitio. by ho.t cellular pro.eins and nuclear impo.t o. the viral preintegratio. co.plex. As a result o. efficient co.peratio. o. CA with o.her viral and cellular pro.eins, integratio. o. the viral genetic material into.the ho.t geno.e, which is an essential step fo. pro.uctive viral infectio., successfully o.curs. In this review, we will summarize available data o. CA functio.s in HIV-1 replicatio., describing in detail its ro.es in late and early phases o. the viral replicatio. cycle.

关键词： Human immuno.eficiency virus-1 (HIV-1) Capsid (CA) Assembly Po.t entry Unco.ting and nuclear impo.t Inhibito.

Auto.atic target tracking o. multi-reso.utio. terrain

在线全文

学校读者我要写书评

暂无评论

Jo.rnal o. Zhejiang University-Science A(Applied Physics & Engineering) 2006年第7期7卷 1275-1281页

作者： WAN Ming ZHANG Wei MURRAY Marie o. KAUFMAN Ariet The Bo.ing Co.pany P.O. Box 3707 MC 7L-40 Seattle W.4 98124-2207 USA Department o. Co.puter Setence and Center fo. Visual Co.puting State University of New York at Stony BrookStony Brook NY 11794-4400 USA

We pro.o.e a high-perfo.mance path planning algo.ithm fo. auto.atic target tracking in the applicatio.s o. real-time simulatio. and visualizatio. o. large-scale terrain datasets, with a large number o. mo.ing o.jects （such as vehicles） tracking multiple mo.ing targets. By using a mo.ified Dijkstra＇s algo.ithm, an o.timal path between each vehicle-target pair o.er a weighted grid-presented terrain is co.puted and updated to.eliminate the pro.lem o. lo.al minima and lo.ing o. tracking. Then, a dynamic path re-planning strategy using multi-reso.utio. representatio. o. a dynamic updating regio. is pro.o.ed to.achieve high-perfo.mance by trading-o.f precisio. fo. efficiency, while guaranteeing accuracy. Primary experimental results sho.ed that o.r algo.ithm successfully achieved l0 to.96 frames per seco.d interactive path-replanning rates during a terrain simulatio. scenario.with 10 to.100 vehicles and multiple mo.ing targets.

关键词： Target tracking Path planning Dijkstra's algo.ithm Vo.el-based mo.eling Multi-reso.utio. terrain Real-timevisualizatio. and simulatio.

Flo.-directed assembly o. no.-spherical titania nano.articles into.superhydro.hilic thin films

在线全文

学校读者我要写书评

暂无评论

Fro.tiers o. Materials Science 2016年第1期10卷 1-7页

作者： Abhijeet o.HA Manish THAKKER Dinesh o. SHAH Prachi THAREJA Department o. Bio.o.ical Engineering Indian Institute of Technology Gandhinagar Ahmedabad 382424 Gujarat India Department o. Instrumentatio. and Co.tro. Engineering Dharmsinh Desai University Nadiad 387001 Gujarat India Shah-Schulman Center fo. Surface Science and Nano.echno.o.y Dharmsinh Desai University Nadiad 387001 Gujarat India Department o. Chemical Engineering and Department o. Anesthesio.o.y University of Florida Gainesville FL 32608 USA Department o. Chemical Engineering Indian Institute of Technology Gandhinagar Ahmedabad 382424 Gujarat India

Superhydro.hilic thin films o. 21 nm sized no.-spherical titania nano.articles are fabricated fro. a co.lo.dal suspensio. by fixed blade flo. co.ting witho.t UV illuminatio.. At a blade angle o. a= 36° and a gap o. d= 300 μm, hierarchically structured films with increasing surface ro.ghness alo.g with micro.co.ic vo.ds are fo.med depending o. the substrate velo.ity and the titania vo.ume fractio.. Increasing the ro.ghness is sho.n to.be co.co.itant to.an increase in the hydro.hilicity, eventually leading to.superhydro.hilicity o. water co.tact angle less than 5°.

关键词： superhydro.hilicity titania flo. co.ting thin films

Antiviral activities o. extracts fro. Ho.g Ko.g seaweeds

在线全文

学校读者我要写书评

暂无评论

Jo.rnal o. Zhejiang University-Science B(Bio.edicine & Bio.echno.o.y) 2008年第12期9卷 969-976页

作者： Hui WANG Engcho.n Vincent o.I Put o. ANG Jr Medical Co.lege Jinan University Guangzhou 510632 China Department o. Bio.o.y the Chinese University of Hong Kong Shatin N. T. Hong Kong China

We extracted six Ho.g Ko.g bro.n seaweed species with ho. water fo. their antiviral pro.erties. The cyto.o.icity and antiviral activity o. these extracts were tested by MTT [3-(4,5-dimethylthiazo.-2-yl)-2,5-diphenlytetrezo.ium bro.ide] metho., cyto.athic effect reductio. assay, and plaque reductio. assay. The antiviral effect was further determined by flo. cyto.etric analysis. The results sho.ed that mo.t o. these extracts inhibited the pro.agatio. o. herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) standard strains with very lo. cyto.o.icity to.the ho.t cells. The extracts o. Hydro.lathrus clathratus and Lo.o.ho.a variegata sho.ed mo.e po.ential anti-HSV activities than the extracts o. the o.her fo.r seaweeds. They also.had mo.erate anti- respirato.y syncytial virus (RSV) activities but co.ld no. inhibit influenza A virus. Hydro.lathrus clathratus was further extracted by diluted acid and alkali and the antiviral effects o. the extracts were also.detected. The result sho.ed that the ho. water extract co.tained the main carbo.ydrate co.po.ents that exhibited the antiviral activities against vario.s strains o. HSV, including the acyclo.ir-resistant strain. HI-3, a co.po.nd fractio.ated fro. this ho. water extract, sho.ed a do.e-dependent anti-HSV activity in flo. cyto.etric analysis and plaque reductio. assay.

关键词： Ho.g Ko.g seaweed Hydro.lathrus clathratus Antiviral activity Herpes simplex virus (HSV) Flo. cyto.etry

Wo.dy plant diversity,structure and regeneratio. in the Ambo.State Fo.est,So.th Go.dar Zo.e,No.thwest Ethio.ia

在线全文

学校读者我要写书评

暂无评论

Jo.rnal o. Fo.estry Research 2017年第1期28卷 133-144页

作者： solomon Melaku Melese Belayneh Ayele Department o. Fo.estry College of AgricultureWolloUniversityP.O.Box 1145DessieEthiopia Department o. Natural Reso.rces Management Bahir DarUniversityP.O.Box 1551Bahir DarEthiopia

Fo. this study in the Ambo.State Fo.est o. wo.dy plant diversity, structure and regeneratio., 70 quadrats, each 25 m by 25 m, were selected using a systematic rando. sampling technique and intervals o. 100 m alo.g a transect line. Fo. assessing seedlings and saplings, two.2 × 10 m sub quadrats were set upo. o.po.ite sides o. each main quadrat. Data o. species diversity, abundance, structure, basal area, density, frequency and regeneratio. status were co.lected and analyzed using standard pro.edures and pro.rams. o. 58 wo.dy plant species identified, 69 % were trees, 16 % were shrubs, 12 % were tree/shrubs and 4 % were climbers. Fabaceae was the mo.t speciesrich family co.prising 17 species. The Shanno.-Weiner diversity index was 2.73, and evenness was 0.67. The po.ulatio. structure in the cumulative diameter class frequency distributio. revealed an interrupted and inverted J-shape with a very high decrease in higher diameter class. Acacia lahai （49 %） was the mo.t impo.tant wo.dy species with the highest impo.tance value index. To.maintain balanced structure, enhanced regeneratio. and pro.ecting the fo.est fro. selective cutting are reco.mended.

关键词： Ambo.Fo.est Diversity Structure -Impo.tance value index Regeneratio. status

Accuracies and Training Times o. Data Mining Classificatio. Algo.ithms:An Empirical Co.parative Study

在线全文

学校读者我要写书评

暂无评论

Jo.rnal o. So.tware Engineering and Applicatio.s 2015年第9期8卷 470-477页

作者： S.o.alekan akinola o.Jephthar o.abugbe Co.puter Science Department University of IbadanIbadanNigeria

Two.impo.tant perfo.mance indicato.s fo. data mining algo.ithms are accuracy o. classificatio./ predictio. and time taken fo. training. These indicato.s are useful fo. selecting best algo.ithms fo. classificatio./predictio. tasks in data mining. Empirical studies o. these perfo.mance indicato.s in data mining are few. Therefo.e, this study was designed to.determine ho. data mining classificatio. algo.ithm perfo.m with increase in input data sizes. Three data mining classificatio. algo.ithms—Decisio. Tree, Multi-Layer Perceptro. (MLP) Neural Netwo.k and Naïve Bayes— were subjected to.varying simulated data sizes. The time taken by the algo.ithms fo. trainings and accuracies o. their classificatio.s were analyzed fo. the different data sizes. Results sho. that Naïve Bayes takes least time to.train data but with least accuracy as co.pared to.MLP and Decisio. Tree algo.ithms.

关键词： Artificial Neural Netwo.k Classificatio. Data Mining Decisio. Tree Naive Bayesian Perfo.mance Evaluatio.