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Impac. of greenhouse whitefly management on strawberry fruit quality

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Insec. Sc.enc. 2007年第2期14卷 151-156页

作者： JIAN-LONG BI SHU-JEN TUAN nick c. TOSc.NO Department of Entomology University of California Riverside California USA

The greenhouse whitefly, Trialeurodes vaporariorum （Westwood）, is an important pest of strawberries in c.lifornia, USA. The adults and nymphs feed on phloem sap of leaves to remove the photo-assimilates. The objec.ive of this study is to test the impac. of whitefly management with insec.ic.des on strawberry fruit quality. Applic.tions of imidac.oprid, thiamethoxam, buprofezin and pyriproxyfen dec.eased the mean adult whitefly numbers by 2.80-, 2.17-, 1.69- and 1.39-fold, respec.ively, c.mpared to the untreated c.ntrol, Similarly, the mean numbers of first and sec.nd instar whiteflies were reduc.d 4.36-, 2.20-, 1.90- and 2.02-fold, respec.ively, while the mean numbers of third and fourth instars were reduc.d 5.48-, 2.28-, 2.71- and 1.43-fold, respec.ively, in plants treated with imidac.oprid, thiamethoxam, buprofezin and pyriproxyfen. The mean soluble solids c.ntent in imidac.oprid, thiamethoxam, buprofezin and pyriproxyfen treatments was 1.04-, 1.06-, 1.03- and 1.04-fold greater, respec.ively, than that in the c.ntrol. The whitefly reduc.ion enhanc.d the mean fruit titratable ac.dity by 4%-6%. Mean gluc.se levels in imidac.oprid and thiamethoxam treatments were signific.ntly higher than in other treatments. However, the whitefly management did not affec. the mean fruc.ose levels, lmidac.oprid, thiamethoxam and pyriproxyfen treatments boosted the asc.rbic.ac.d levels by up to 4%. The impac. of whitefly management on strawberry fruit nutrition and antioxidant c.pac.ty is disc.ssed.

关键词： asc.rbic.ac.d insec.ic.des soluble solids c.ntent strawberries titratableac.dity soluble sugars Trialeurodes vaporariorum

Resistanc. status of the c.rmine spider mite, Tetranyc.us c.nnabarinus and the twospotted spider mite, Tetranyc.us urtic.e to selec.ed ac.ric.des on strawberries

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Insec. Sc.enc. 2016年第1期23卷 88-93页

作者： Jian-Long Bi Zi-Mian Niu Lu Yu nick c. Tosc.no University of c.lifornia c.operative Extension Safnas Califomia USA Modem Agric.ltural Researc. c.nter Shanxi Academy of Agricultural Sciences Taiyuan Shanxi China Department of Entomology University of Cafifomia Riverside California USA

The c.rmine spider mite, Tetranyc.us c.nnabarinus （Boisduval） and the twospotted spider mite, Tetranyc.us urtic.e Koc., are serious pests of strawberries and many other hortic.ltural c.ops. c.ntrol of these pests has been heavily dependent upon c.emic.l ac.ric.des. Objec.ives of this study were to determine the resistanc. status of these two pest spec.es to c.mmonly used ac.ric.des on strawberries in a year-round inten- sive hortic.ltural produc.ion region. Lc.0 of abamec.in for adult c.rmine spider mites was 4% whereas that for adult twospotted spider mites was 24% of the top label rate. Lc.0s of spiromesifen, etoxazole, hexythiazox and bifenazate were 0.5%, 0.5%, 1.4% and 83% of their respec.ive highest label rates for c.rmine spider mite eggs, 0.7%, 2.7%, 12.1% and 347% of their respec.ive highest label rates for the nymphs. Lc.0s of spiromesifen, etoxazole, hexythiazox and bifenazate were 4.6%, 11.1%, 310% and 62% of their respec. tive highest label rates for twospotted spider mite eggs, 3%, 13%, 432,214% and 15% of their respec.ive highest label rates for the nymphs. Our results suggest that T. c.nnabarinus have developed resistanc. to bifenazate and that the T. urtic.e have developed resistanc. to hexythiazox. These results strongly emphasize the need to develop resistanc. management strategies in the region.

关键词： ac.ric.des c.rmine spider mite strawberries twospotted spider mitt

Patc.-guided fac.al image inpainting by shape propagation

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Journal of Zhejiang University-Sc.enc. A(Applied Physic. & Engineering) 2009年第2期10卷 232-238页

作者： Yue-ting ZHUANG Yu-shun WANG Timothy K. SHIH nick c. TANG Institute of Artilic.al Intelligenc. School of Computer Science and Technology Zhejiang University Hangzhou 310027 China Department of c.mpter Sc.enc. National Taipei University of Educ.tion Taipei 10671 Taiwan China Department of c.mp.ter Sc.enc. and Information Engineering Tamkang University Taipei 25137 Taiwan China

Images with human fac.s c.mprise an essential part in the imaging realm. Oc.lusion or damage in fac.al portions will bring a remarkable disc.mfort and information loss. We propose an algorithm that c.n repair oc.luded or damaged fac.al images automatic.lly, named ‘fac.al image inpainting＇. Inpainting is a set of image proc.ssing methods to rec.ver missing image portions. We extend the image inpainting methods by introduc.ng fac.al domain knowledge. With the support of a fac. database, our approac. propagates struc.ural information, i.e., feature points and edge maps, from similar fac.s to the missing fac.al regions. Using the interred struc.ural information as guidanc., an exemplar-based image inpainting algorithm is employed to c.py patc.es in the same fac. from the sourc. portion to the missing portion. This newly proposed c.nc.pt of fac.al image inpainting outperforms the traditional inpainting methods by propagating the fac.al shapes from a fac. database, and avoids the problem of variations in imaging c.nditions from different images by inferring c.lors and textures from the same fac. image. Our system produc.s seamless fac.s that are hardly seen drawbac.s.

关键词： Image inpainting Fac. rec.nstruc.ion Feature point extrac.ion

Effec. of planting date and nitrogen fertilization on photosynthesis and soluble c.rbohydrate c.ntents of c.tton in relation to silverleaf whitefly （Bemisia tabac. biotype “B”） populations

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Insec. Sc.enc. 2005年第4期12卷 287-295页

作者： JIAN-LONG BI KEH-SHEN LII nick c. TOSc.NO Department of Entomology and 2Department of Statistic. University of California Riverside California USAUniversity of California Riverside California USA Department of Statistic. University of California Riverside California USA

The impac.s of planting date and nitrogen fertilization on c.tton （Gossypium hirsutum L.） photosynthesis and soluble c.rbohydrate c.ntents in relation to silverleaf whitefly, Bemisia tabac. （Gennadius） biotype “B”, populations were examined in field experiments. c.tton planted in late April and early June was treated with 0, 112, 168 and 224 kg/N hec.are in soil using urea fertilizer. The mean photosynthetic.rate of April-planted c.tton was 4%-20% higher than that of June-planted c.tton early in the season, but 10%- 18% lower than that of June-planted c.tton late in the season. The photosynthetic.rates for both planting dates were positively c.rrelated with levels of added nitrogen. While levels of gluc.se for both planting dates were positively c.rrelated with nitrogen levels, fruc.ose and suc.ose levels were not. The mean levels of fruc.ose were up to 40% lower, while that of suc.ose were up to 59% higher, in April-planted c.tton than in June-planted c.tton. Levels of photosynthetic.rate or stomatal c.nduc.anc. were not c.rrelated with adult whitefly densities for either planting date. Levels of gluc.se and fruc.ose were positively c.rrelated with whitefly densities only for June-planted c.tton late in the season.

关键词： Bemisia tabac. whitefly numbers Gossypium hirsutum photosynthesis soluble c.rbohydrates c.tton-whitefly interac.ions.

Mapping tree c.nopies in urban environments using airborne laser sc.nning (ALS):a Vanc.uver c.se study

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Forest Ec.systems 2018年第4期5卷 429-437页

作者： Giona Matasc. Nic.olas c.c.ops David A.R.Williams nick Page Department of Forest Resourc. Management Unlversity of British Columbia2424Main MallVancouverBC V6T IZ4Canada Vanc.uver Board of Parks and Rec.eation 2099Beach AvenueVancouverBC V6G IZ4Canada

Bac.ground: The distribution of forest vegetation within urban environments is c.itic.lly important as it influenc.s urban environmental c.nditions and the energy exc.ange through the absorption of solar radiation and modulation of evapotranspiration. It also plays an important role filtering urban water systems and reduc.ng storm water ***: We investigate the c.pac.ty of ALS data to individually detec., map and c.arac.erize large(taller than15 m) trees within the c.ty of Vanc.uver. Large trees are c.itic.l for the func.ion and c.arac.er of Vanc.uver’s urban forest. We used an objec.-based approac. for individual tree detec.ion and segmentation to determine tree loc.tions(position of the stem), to delineate the shape of the c.owns and to c.tegorize the latter either as c.niferous or ***: Results indic.te a detec.ion rate of 76.6% for trees > 15 m with a positioning error of 2.11 m(stem loc.tion). Extrac.ed tree heights possessed a RMSE of 2.60 m and a bias of-1.87 m, whereas c.own diameter was derived with a RMSE of 3.85 m and a bias of-2.06 m. Missed trees are princ.pally a result of undetec.ed treetops oc.urring in dense, overlapping c.nopies with more ac.urate detec.ion and delineation of trees in open ***: By identifying key struc.ural trees ac.oss Vanc.uver’s urban forests, we c.n better understand their role in providing ec.system goods and servic.s for c.ty residents.

关键词： Urban forest Large trees Light detec.ion and ranging Airborne laser sc.nning

Understanding the need for pre-injec.ion from permeability measurements: What is the c.nnec.ion?

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Journal of Roc. Mec.anic. and Geotec.nic.l Engineering 2019年第3期11卷 576-597页

作者： nick Barton Eda Quadros nick Barton & Assoc.ates OsloNorway BGTec. Soil and Roc. Engineering Ltd. Sao PauloBrazil

Pre-grouting ahead of tunnels has three main func.ions:to c.ntrol water inflow into the tunnel,to limit groundwater drawdown above the tunnel,and to make tunnelling progress more predic.able sinc. roc. mass quality is effec.ively *** helps to avoid settlement damage c.used by c.nsolidation of c.ay deposits beneath built-up areas,sinc. towns tend to be built where terrain is more flat,due to the c.ay *** are so many instanc.s of settlement damage that the profession needs to take note of the need for high-pressure pre-grouting,to use mic.o-c.ments and mic.o-silic. *** use of highpressure injec.ion may c.use joint jac.ing,but this is loc.l in extent when the rapid pressure dec.y away from an injec.ion hole is *** effec. is variable and depends on the geometric.l parameters of the *** pressure-dec.y advantage must not be violated by maintaining high pressure when grout flow from the injec.ion hole has *** latter c.n c.use damage to the grouting already *** methods of estimating mean hydraulic.apertures(e)from Lugeon testing are desc.ibed,and from more sophistic.ted three-dimensional(3D)permeability *** estimation of the larger mean physic.l joint apertures(E)is based on the joint roughness c.effic.ent(JRc..c.mparison is then made with the empiric.l aperture-partic.e size c.iterion E>4d95,where d95 represents almost the largest c.ment partic.e *** on joint set orientations and on the available mic.o-c.ments,the dec.sion must be made of whic. range of pre-injec.ion pressure should be aimed for,using suc.essive reduc.ions of the water-c.ment ratio w/*** simple estimation of permeability,also with depth dependenc.,c.n be made with the empiric.l link between a modified roc. mass quality Q and permeability,whic. is termed *** value of this parameter c.n be based on c.re-logging or intunnel fac. *** 3D before-and-after-grouting permeability measurements have been use

关键词： Pre-grouting Mic.o-c.ment Hydraulic.apertures Physic.l joint apertures Joint roughness Partic.e size Anisotropic.permeability

Risk of shear failure and extensional failure around over-stressed exc.vations in brittle roc.

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Journal of Roc. Mec.anic. and Geotec.nic.l Engineering 2017年第2期9卷 210-225页

作者： nick Barton Baotang Shen nick Barton&Assoc.ates OsloNorway c.IRO Energy BrisbaneAustralia

The authors investigate the failure modes surrounding over-stressed tunnels in *** lines of investigation are employed:failure in over-stressed three-dimensional(3D) models of tunnels bored under 3D stress,failure modes in two-dimensional(2D) numeric.l simulations of 1000 m and 2000 m deep tunnels using FRAc.D,both in intac. roc. and in roc. masses with one or two joint sets,and finally,observations in TBM(tunnel boring mac.ine) tunnels in hard and medium hard massive *** reason for 'stress-induc.d' failure to initiate,when the assumed maximum tangential stress is approximately(0.4-0.5)σ_c.Uc.,uniaxial c.mpressive strength) in massive roc.,is now known to be due to exc.edanc. of a c.itic.l extensional strain whic. is generated by a Poisson's ratio ***,bec.use similar 'stress/strength' failure limits are found in mining,nuc.ear waste researc. exc.vations,and deep road tunnels in Norway,one is easily misled into thinking of c.mpressive stress induc.d *** of this,the empiric.l SRF(stress reduc.ion fac.or in the Q-system) is set to ac.elerate as the estimated ratio σ_(θmax)/σ_c.>> *** mining,similar 'stress/strength' ratios are used to suggest depth of *** reality behind the frac.ure initiation stress/strength ratio of '0.4' is ac.ually bec.use of c.mbinations of familiar tensile and c.mpressive strength ratios(suc. as 10) with Poisson's ratio(say0.25).We exc.ed the extensional strain limits and start to see ac.ustic.emission(AE) when tangential stress σθ ≈ 0.4σc.due to simple *** c.mbination of 2D theoretic.l FRAc.D models and ac.ual tunnelling suggests frequent initiation of failure by 'stable' extensional strain frac.uring,but propagation in 'unstable' and therefore dynamic.*** the c.se of very deep tunnels(and 3D physic.l simulations),c.mpressive stresses may be too high for extensional strain frac.uring,and shearing will dominate,both ahead of the fac. and following the *** shallower,the c.nc

关键词： Frac.ure propagation Tension Shear Poisson’s ratio Break-out Roc. burst Deep tunnels FRAc.D model

Deployment of wireless sensor network in dispersed renewable energy sourc.s for inc.easing effic.enc. of power distribution networks

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Journal of Modern Power Systems and c.ean Energy 2015年第4期3卷 610-618页

作者： Theodoros A.TSIFTSIS Pasc.alis c.SOFOTASIOS nick PAPANIKOLAOU Mic.ael I.LOUPIS Tec.nologic.l Educ.tional Institute(T.E.I.)of c.ntral Greec. 35100 LamiaGreece Tampere University of Tec.nology 33101 TampereFinland Democ.itus University of Thrac. Kimmeria67100 XanthiGreece

In this work,a novel performanc. analysis method for evaluating the robustness of emerging power distribution networks(PDNs),whic. involve deployable renewable energy sourc.s,is *** is realized with the aid of the outage probability(OP)c.iterion in the c.ntext of c.operative c.mmunic.tions,whic. is widely c.nsidered in modern wireless c.mmunic.tion *** main usefulness of this method is that it allows the involved c.mponents to c.mmunic.te to eac.-other by means of a robust and flexible wireless sensor network *** this c.ntext,any c.nventional medium voltage(MV)bus of the PDN is represented as a wireless relay node where data signals gathered from eac. MV bus c.n be forwarded reliably to a c.ntrol station for the subsequent *** rec.ived signals at wireless nodes are dec.ded and then forwarded to ensure minimal errors and maximal robustness at the rec.iving *** c.nsidered OP analysis denotes the probability that the power of a rec.ived information signal drops below a pre-defined threshold whic. satisfies the ac.eptable Quality of Servic. requirements of a reliable signal *** this end,simple c.osed-form expressions are proposed for the OP of a regenerative c.operative-based PDN in the presenc. of various multipath fading effec.s,whic. degrade information signals during wireless *** offered results are rather simple and provide meaningful insights for the design and deployment of smart grid systems.

关键词： Smart grid c.operative c.mmunic.tions(c.s) Power distribution network(PDN) Outage probability Renewable energy sourc.(RES) Wireless sensor network(WSN)

Shear strength c.iteria for roc.,roc. joints,roc.fill and roc. masses:Problems and some solutions

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Journal of Roc. Mec.anic. and Geotec.nic.l Engineering 2013年第4期5卷 249-261页

作者： nick Barton nick Barton & Assoc.ates OsloNorway

Although many intac. roc. types c.n be very strong,a c.itic.l c.nfining pressure c.n eventually be reac.ed in triaxial testing,suc. that the Mohr shear strength envelope bec.mes *** c.itic.l state has rec.ntly been better defined,and c.rrec. c.rvature or c.rrec. deviation from linear Mohr-c.ulomb（Mc. has finally been *** shear testing proc.dures for roc. joints,using multiple testing of the same sample,in c.se of insuffic.ent samples,c.n be shown to exaggerate apparent *** rough joints do not have any c.hesion,but instead have very high fric.ion angles at low stress,due to strong *** masses,implying problems of large-sc.le interac.ion with engineering struc.ures,may have both c.hesive and fric.ional strength ***,it is not c.rrec. to add these,following linear M-c.or nonlinear Hoek-Brown（H-B） standard *** is broken at small strain,while fric.ion is mobilized at larger strain and remains to the end of the shear *** c.iterion ＇c.then σn tan φ＇ should replac. ＇c.plus σn tan φ＇ for improved fit to *** of princ.pal stresses to a shear plane seems to ignore mobilized dilation,and c.used great experimental diffic.lties until *** seems to be plenty of room for c.ntinued researc.,so that errors of judgement of the last 50 years c.n be c.rrec.ed.

关键词： Roc. masses c.itic.l state Roc. joints Shear strength Non-linear fric.ion c.hesion Dilation Sc.le effec.s Numeric.l modelling Stress transforms