检索结果-南通市图书馆

j.urnal.of Integrative Agricul.ure 2014年第6期13卷 1404-1411页

作者： David l. Ortega H. Hol.y Wang Nicol. j. Ol.nk Widmar Department of Agricul.ural Foodand Resource EconomicsMichigan State University Department of Agricul.ural.Economics Purdue University

This study provides an economics assessment of various food safety measures in China. A choice experiment approach is used to el.cit Chinese consumer preferences for various food safety attributes using data from a 2008 urban consumer survey. An al.ernative wel.are cal.ul.tion is used to model.aggregate market impacts of sel.ct food safety measures. Our resul.s show that the l.rgest wel.are gains are found in the current government-run certiifcation program. The impl.mentation of a third-party certiifcation system, a traceabil.ty network and a product l.bel.woul. generate signiifcant val.e and woul. hel. reduce current system inefifciencies in China. This study buil.s on previous research and provides an al.ernative approach for cal.ul.ting consumer val.ation of safety and qual.ty attributes that can be used to estimate aggregate economic and wel.are impacts.

关键词： food safety consumer wel.are food pol.cy China

A Note on the Rel.tionship Between Temperature and Water Vapor over Oceans, Incl.ding Sea Surface Temperature Effects

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2006年第1期23卷 141-148页

作者： C.-l. SHIE W.-K. TAO j. SIMPSON Goddard Earth Sciences and Technol.gy Center University of MarylandBaltimore CountyBaltimoreMaryland 21250USA Laboratory for AtmospheresNASA Goddard Space Flight CenterGreenbeltMaryland 20771USA l.boratory for Atmospheres NASA Goddard Space Flight CenterGreenbeltMaryland 20771USA

An ideal.and simpl. formul.tion is successful.y derived that wel. represents a quasi-l.near rel.tionship found between the domain-averaged water vapor, Q （ram）, and temperature, T （K）, fiel.s for the three tropical.oceans （i.e., the Pacific, Atl.ntic and Indian Oceans） based on el.ven GEOS-3 [Goddard Earth Observing System （EOS） Version-3] gl.bal.re-anal.sis monthl. products. A Q - T distribution anal.sis is al.o performed for the tropical.and extra-tropical.regions based on in-situ sounding data and numerical.simul.tions [GEOS-3 and the Goddard Cumul.s Ensembl. （GCE） model.. A simil.r positivel. correl.ted Q - T distribution is found over the entire oceanic and tropical.regions; however, Q increases faster with T for the former region. It is suspected that the tropical.oceans may possess a moister boundary l.yer than the Tropics. The oceanic regime fal.s within the l.wer bound of the tropical.regime embedded in a gl.bal. curvil.near Q - T rel.tionship. A positive correl.tion is al.o found between T and sea surface temperature （SST）; however, for one degree of increase in T, SST is found to increase 1.1 degrees for a warmer ocean, which is sl.ghtl. l.ss than an increase of 1.25 degrees for a col.er ocean. This seemingl. indicates that more （l.ss） heat is needed for an open ocean to maintain an air mass above it with a same degree of temperature rise during a col.er （warmer） season [or in a col.er （warmer） region]. Q and SST are al.o found to be positivel. correl.ted. Rel.tive humidity （RH） exhibits simil.r behaviors for oceanic and tropical.regions. RH increases with increasing SST and T over oceans, whil. it increases with increasing T in the Tropics. RH, however, decreases with increasing temperature in the extratropics. It is suspected that the tropical.and oceanic regions may possess a moister l.cal.boundary l.yer than the extratropics so that a faster moisture increase than a saturated moisture increase is favored for the former regions. T, Q, saturated water v

关键词： moisture temperature rel.tionship quasi-equil.brium states Tropics oceans

An underl.ing geometrical.manifol. for Hamil.onian mechanics

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2017年第1期12卷 123-131页

作者： l. P. Horwitz A. Yahal.m j. l.vitan M. l.wkowicz School.of Physics Tel Aviv University Ramat Aviv 69978 Israel Department of Physics Bar llan University Ramat Gan 52900 Israel Department of Physics Ariel University Ariel 40700 Israel Department of El.ctrical.and El.ctronic Engineering Ariel University Ariel 40700 Israel

We show that there exists an underl.ing manifol. with a conformal.metric and compatibl. connection form, and a metric type Hamil.onian （which we cal. the geometrical.picture）, that can be put into correspondence with the usual.Hamil.on-l.grange mechanics. The requirement of dynamical.equiva- l.nce of the two types of Hamil.onians, that the momenta generated by the two pictures be equal.for al. times, is sufficient to determine an expansion of the conformal.factor, defined on the geometrical.coordinate representation, in its domain of anal.ticity with coefficients to al. orders determined by functions of the potential.of the Hamil.onian-l.grange picture, defined on the Hamil.on-l.grange coordinate representation, and its derivatives. Conversel., if the conformal.function is known, the potential.of a Hamil.on-l.grange picture can be determined in a simil.r way. We show that arbi- trary l.cal.variations of the orbits in the Hamil.on-l.grange picture can be generated by variations al.ng geodesics in the geometrical.picture and establ.sh a correspondence which provides a basis for understanding how the instabil.ty in the geometrical.picture is manifested in the instabil.ty of the the original.Hamil.onian motion.

关键词： geometrical.Hamil.onian stabil.ty anal.sis coordinate mapping Riemann-Eucl.dean Hamil.onian equival.nce

Quantitative Appl.cations of Weather Satel.ite Data for Nowcasting:Progress and Chal.enges

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

j.urnal.of Meteorol.gical.Research 2024年第3期38卷 399-413页

作者： j.n l. j.ng ZHENG Bo l. Min MIN Yanan l.U Chian-Yi l.U Zhengl.ng l. WPaul.MENZEl.Timothy j.SCHMIT j.hn l.CINTINEO Scott l.NDSTROM Scott BACHMEIER Yunheng XUE Yayu MA Di DI Han l.N Innovation Centre for Fengyun Meteorol.gical.Satel.ite(FYSIC) National Satellite Meteorological CentreChina Meteorological AdministrationBeijing100081China School.of Atmospheric Sciences and Guangdong Province Key l.boratory for Cl.mate Change and Natural.Disaster Studies Sun Yat-sen University and Southern Laboratory of Ocean Science and EngineeringZhuhai519082China Key l.boratory of Geographic Information Science(Ministry of Education) East China Normal UniversityShanghai200241China Research Center for Environmental.Changes Academia SinicaTaipei11529China Cooperative Institute for Meteorol.gical.Satel.ite Studies University of Wisconsin-MadisonMadisonWI53706USA Sensors and Cal.bration Branch STAR/NESDISMadisonWI53706USA Wuxi University Wuxi214105China School.of Computer Science Chengdu University of Information TechnologyChengdu610225China Col.aborative Innovation Center on Forecast and Eval.ation of Meteorol.gical.Disasters Nanjing University of Information Science&TechnologyNanjing210044China Key l.boratory of Spatial.Data Mining and Information Sharing of Ministry of Education National and Local Joint Engineering Research Center of Satellite Geospatial Information TechnologyFuzhou UniversityFuzhou350108China

Monitoring and predicting highl. l.cal.zed weather events over a very short-term period,typical.y ranging from minutes to a few hours,are very important for decision makers and publ.c *** these events usual.y rel.es on radar observations through monitoring and *** advanced high-resol.tion imaging and sounding observations from weather satel.ites,nowcasting can be enhanced by combining radar,satel.ite,and other data,whil. quantitative appl.cations of those data for nowcasting are advanced through using machine l.arning *** appl.cations incl.de monitoring the l.cation,impact area,intensity,water vapor,atmospheric instabil.ty,precipitation,physical.properties,and optical.properties of the severe storm at different stages(pre-convection,initiation,devel.pment,and decaying),identification of storm types(wind,snow,hail.etc.),and predicting the occurrence and evol.tion of the *** observations can provide information on the environmental.characteristics in the preconvection stage and are very useful.for situational.awareness and storm *** paper provides an overview of recent progress on quantitative appl.cations of satel.ite data in nowcasting and its chal.enges,and future perspectives are al.o addressed and discussed.

关键词： weather satel.ite quantitative appl.cations nowcasting pre-convection

CORBA-Based Discrete Event Simul.tion System

在线全文

学校读者我要写书评

暂无评论

j.urnal.of Systems Engineering and El.ctronics 2001年第3期12卷 16-19页

作者： l.o, j. Zheng, S. Zhong, l. Duan, F. Neocomputer Research Xi'an Jiaotong University Xi'an 710049 China

The CORBA technique is an integration of the obj.ct-oriented conception and distributed computing technique. It can make the appl.cation within distributed heterogeneous environments reusabl., portabl. and interoperabl.. The architecture of CORBA-based discrete event simul.tion systems is presented and the interface of distributed simul.tion obj.cts (DSO) is defined in this paper after the DSO is identified and the synchronization mechanism among DSO is discussed.

关键词： Computational.methods Computer architecture Computer simul.tion Computer software portabil.ty Computer software reusabil.ty Interfaces (computer) Interoperabil.ty Obj.ct oriented programming Synchronization

Extraction of copper ions by supercritical.carbon dioxide

在线全文

学校读者我要写书评

暂无评论

j.urnal.of Environmental.Sciences 2000年第4期12卷 444-447页

作者： Cui, Z. l.u, j. Gao, l. Wei, Y. Dept. of Environmental.Engineering Shandong University Jinan 250100 China

Compl.xation combined with supercritical.fl.id extraction was used to extract Cu2+ in this study. The effects of pressure, temperature, vol.me of CO2 on the efficiency of extraction were systematical.y investigated. At the optimum condition a 57.32% recovery was achieved. Addition of suitabl. amount of methanol.(v/v = 5%) to the supercritical.CO2 can increase in the extraction of Cu2+ (72.69%, RSD = 2.12%, n = 3). And the recovery can further increase in the presence of non-ionic surfactant Triton X-100 because of its function of sol.bil.zation. Surfactant was first used in the extraction of metal.ions in the present study, and the resul.s are satisfied (90.52%, RSD = 2.20%, n = 3).

关键词： Carbon dioxide Chel.tion Copper Methanol Positive ions Pressure effects Sol.bil.ty Surface active agents Thermal.effects

Harnessing natural.y occurring mutations for T-cel. therapy:a potential.new avenue to enhance treatment efficacy

在线全文

学校读者我要写书评

暂无评论

Signal.Transduction and Targeted Therapy 2024年第5期9卷 1799-1801页

作者： Michael.Hil.ensperger j.rgen Rul.nd Kil.an Schober Mikrobiol.gisches Institut-Kl.nische Mikrobiol.gie Immunologie und HygieneFriedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany Institute of Cl.nical.Chemistry and Pathobiochemistry School of MedicineTechnical University of MunichMunichGermany Transl.TUM Center for Translational Cancer ResearchTechnical University of MunichMunichGermany German Cancer Consortium(DKTK) HeidelbergGermany German Center for Infection Research(DZIF) partner site MunichMunichGermany FAU Profil. Center Immunomedicine Friedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany

In a recent study publ.shed in Nature,Garcia et *** a sophisticated approach to identify fitness-enhancing mutations for T cel.s that was inspired by cancer evol.tion.1 The identified CARD11-PIK3R3 gene fusion enhanced tumor rej.ction and persistence of engineered T cel.s in mul.ipl. tumor model. and might have the potential.to improve efficacy of adoptive T-cel. therapies in cancer patients.

关键词： cancer potential

SEQUENTIAl.QUADRATIC PROGRAMMING METHODS FOR OPTIMAl.CONTROl.PROBl.MS WITH STATE CONSTRAINTS

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Appl.ed Mathematics(A j.urnal.of Chinese Universities) 1993年第2期8卷 163-174页

作者：徐成贤 j.ng de j. l. Department of Mathematics Xi'an j.aotong University 710049 Technol.gy I nirersity of Eindhoven Holland

A kind of direct methods is presented for the sol.tion of optimal.control.probl.ms with state constraints. These methods are sequential.quadratic programming methods. At every iteration a quadratic programming which is obtained by quadratic approximation to l.grangian function and l.near approximations to constraints is sol.ed to get a search direction for a merit function. The merit function is formul.ted by augmenting the l.grangian function with a penal.y term. A l.ne search is carried out al.ng the search direction to determine a step l.ngth such that the merit function is decreased. The methods presented in this paper incl.de continuous sequential.quadratic programming methods and discreate sequential.quadratic programming methods.

关键词： Optimal.Control.Probl.ms with State Constraints Sequential.Quadratic Programming l.grangian Function. Merit Function l.ne Search.

El.CTROCHEMICAl.STUDY ON THE l.CAl.ZED CORROSION OF TWO DIFFERENT TEMPER l.12 Al.OYS

在线全文

学校读者我要写书评

暂无评论

Acta Metal.urgica Sinica(Engl.sh l.tters) 2005年第5期18卷 609-619页

作者： F.H. Cao l. Guo l.j. Zhang Z. Zhang j. Q. Zhang Department of Chemistry Yuquan Campus Zhejiang University Hangzhou 310027 China State Key l.boratory for Corrosion and Protection of Metal. Institute of Metal Research The Chinese Academy of Sciences Shenyang 110016 China

The corrosion behavior of two different aged l.12 al.oys in EXCO （234g/l.NaCl. 50g/l.KNO3 0.1M HNO3） and MIl.H-600 （35g/l.NaCl. 5g/l.（NH4）2SO4） sol.tions were studied using el.ctrochemical.impedance spectroscopy （EIS） in conj.nction with SEM technique respectivel., and the pH variation of the above accel.rated corrosion sol.tion during material. corroding was al.o measured to characterize the corrosion processes. At the beginning of corrosion, EIS pl.ts exhibited two capacitive arcs in the high frequency range （Cd） and mediate frequency range （ Cf） originating from the original.corroded surface and the newl. formed interface respectivel., and a l.w frequency inductive l.op due to the rel.xation phenomenon of reaction intermediates. In the EXCO,sol.tion, the EIS resul.s showed that once the exfol.ation corrosion occurred, the inductive l.op disappeared. The resul.s al.o showed that the exfol.ation corrosion susceptibil.ty of state T6 is much higher than that of state T3, but the intergranul.r corrosion susceptibil.ty has a reverse order. Based on the rel.tionship of EIS resul.s with SEM and metal.oscopy morphol.gies of the corroding substrates and physic-chemical.meaning of EIS parameters, an index （Cf/Cd） has been proposed to characterize the extent of the l.cal.zed corrosion, which variation tal.ies with the real.corrosion extent correctl.. Meanwhil., good agreement was found between the experimental.resul.s and the el.ctrochemical.model.proposed and, good coherence between the el.ctrochemical.features and the distribution type of constituent particl.s of corroding material.was observed.

关键词： el.ctrochemical.impedance spectroscope l.12 al.oy exfol.ation corrosion intergranul.r corrosion

A novel.diagnostic gene region for distinguishing between two pest fruit fl.es:Bactrocera tryoni(Froggatt)and Bactrocera neohumeral.s(Hardy)(Diptera:Tephritidae)

在线全文

学校读者我要写书评

暂无评论

Insect Science 2024年第4期31卷 1285-1295页

作者： Mel.ssa l.Starkie El.zabeth V.Fowl.r Al.xander M.Piper Xiaocheng Zhu Paul.ne Wyatt David Gopurenko Matt N.Krosch Francesca Strutt Karen F.Armstrong Hamish Patrick Mark K.Schutze Mark j.Bl.cket Department of Agricul.ure and Fisheries BiosecurityBrisbaneQueenslandAustralia Agricul.ure Victoria AgriBioBundooraVictoriaAustralia Department of Primary Industries Wagga Wagga Agricultural InstituteWagga WaggaNew South WalesAustralia Forensic Services Group Queensland Police ServiceBrisbaneQueenslandAustralia Department of Pest-management and Conservation Lincoln UniversityLincolnNew Zealand Better Border Biosecurity(B3 B3nz.org.nz)LincolnNew Zealand

Bactrocera tryoni and Bactrocera neohumeral.s are morphol.gical.y simil.r sibl.ng pest fruit fl. species that possess different biol.gical.attributes,geographic distributions,and host *** need to differentiate between the two species is critical.for accurate pest status assessment,management,biosecurity,and maintenance of reference *** morphol.gical.y simil.r,adul.s may be separated based on subtl. characters;however,some characters exhibit intraspecific variabil.ty,creating overl.p between the two ***,there is currentl. no singl. mol.cul.r marker or rapid diagnostic assay that can rel.abl. distinguish between *** and ***;therefore,ambiguous sampl.s remain *** we report the first mol.cul.r marker that can consistentl. distinguish between *** and *** diagnostic region consists of two adj.cent singl. nucl.otide pol.morphisms(SNPs)within the pangol.n(pan)gene *** confirmed the genotypes of each species are consistent across their distributional.range,then devel.ped a tetra-primer ampl.fication refractory mutation system(ARMS)PCR assay for rapid diagnosis of the *** assay util.zes four primers in mul.ipl.x,with two outer universal.primers,and two internal.primers:one designed to target two adj.cent SNPs(AA)present in *** and the other targeting adj.cent SNPs present in ***(GG).The assay accuratel. discriminates between the two species,but their SNP genotypes are shared with other nontarget tephritid fruit fl. ***,this assay is most suited to adul. diagnostics where species confirmation is necessary in determining ambiguous surveil.ance trap catches;maintaining pure col.ny l.nes;and in Steril. Insect Technique management responses.

关键词： ARMS-PCR col.ny mol.cul.r diagnostics pangol.n tetra-primer