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221.
Along with the rapid increase in information of internet,the information research technology was confronted with more and more challenge.Traditional WEB search engine is not satisfied with users' special demand any more,therefore there comes forth a trend to join intelligent technique with Web search engine.This paper puts forward a Multi-agent based architecture for WEB search engine based on traditional architecture.An effective securities business search engine,which is can satisfy user's especial request which is created by means of intelligent technique.If the system is used in many other special fields,good results of information research can also be acquired.  相似文献   
222.
Harry S. Paris 《Euphytica》2003,129(1):119-126
Longitudinal striping of the fruit exterioris a common trait in Cucurbita pepo(pumpkin, squash, gourd). Striping occursas ten pairs of alternating dark and lightstripes that are regularly situated inaccordance with the ten sub-epidermalcarpellary vein tracts. Usually, the darkstripes occur in the central areas betweenthe vein tracts, with the light stripesoccupying the remainder of the fruitsurface. A new phenotype is described inwhich dark spots or streaks occur in thecentral areas between the vein tracts;these are usually accompanied by darkstreaks or stripes that occur adjacent toand over part or all of the length of someor all of the ten carpellary vein tracts. The inheritance of this irregular stripingpattern was studied by crossing anaccession that bred true for this phenotypewith a near-isogenic line havinglight-colored fruits. The resultsindicated that irregular striping isdominant to light coloration and isconferred by a single gene. Testcrossesfor allelism with regular striping wereprepared by crossing the irregularlystriped accession with near-isogenic lineshaving broad stripes, l-1 BSt/l-1 BSt, and narrowstripes, l-1 St/l-1 St. The testcross results revealed thatirregular striping is conferred by anallele at the l-1 locus, designatedl-1 iSt. The l-1 iStallele is dominant to light-colored (l-1), recessive to dark-colored (L-1), and can be co-dominant or recessiveto broad-striped (l-1 BSt) andnarrow-striped (l-1 St),depending on whether or not it is fullyexpressed. Dominance relationships at thel-1 locus can, therefore, berepresented as L-1 > (l-1 BSt > l-1 St) l-1 iSt > l-1.  相似文献   
223.
采用微波消解法处理样品,建立了电感耦合等离子体光谱法同时测定有机肥、复混肥和尿素中铅(Pb)、砷(As)、汞(Hg)、铬(Cr)、镉(Cd)、铜(Cu)、锰(Mn)、钴(Co)、锌(Zn)、镍(Ni)和锑(Sb)11种元素的分析方法。优化了微波消解条件、仪器条件,进行了方法的检出限、精密度、准确性试验。方法检出限为0.003~0.015 mg/L,相对标准偏差均8.1%,回收率为82.4%~103%,通过水系沉积物标准参考样(GBW-07311)及国家标准方法的验证表明,该方法具有简便、快速、准确、灵敏度高等特点,适合有机肥、复混肥和尿素中11种元素的同时测定。  相似文献   
224.
通过对天保工程实施后林区职工的社会保障和就业等问题的深入分析,提出了解决工程区林业职工安置问题的对策。  相似文献   
225.
In the Nordic countries, sets of Indicator (Signal) species, predominantly cryptogams, have been used as one measure to find forest stands which may harbour Red List species. Such data could potentially also be used to prioritise among stands for protection as nature reserves. We studied if the number of Signal species indicates the number of Red List species in oak-rich mixed forest in south Sweden. We also explored if species richness of the investigated groups is correlated with the number of Red List or Signal species. In 25 stands, we surveyed epiphytic and epixylic bryophytes and lichens, ground-floor bryophytes, and wood-living fungi. We studied correlations for two datasets; (1) all forest species and (2) deciduous forest specialists. When relating the number of Signal species to the number of Red List species for each taxon and in total, a significant correlation was found for temperate deciduous forest lichens. The number of Signal species was further significantly correlated to total species richness for lichens (all forest species) and for wood-living fungi (both datasets). The number of Red List lichens was correlated to total lichen richness (deciduous forest species). Signal species seem not to be unequivocal in prioritising potential reserves among valuable oak-rich woodlands and surveys by Red List species experts may be needed. Signal species may be more useful for finding relatively valuable sites in a matrix of production forest. Moreover, Signal species seem to be useful surrogates for total cryptogam species richness.  相似文献   
226.
 通过对黄土丘陵沟壑区几条典型小流域和现有治理模式的分析评价,初步确定了该区不同侵蚀类型区水上保持综合治理的关键措施及其组合方案。各区的组合比例如下。第1副区和第2副区:水平梯田18%~25%,人工造林45%~55%,人工种草20%~25%,坝地5.5%~7.5%,水地0.5%~2.7%;第3副区:水平梯田42%~48%,人工造林32%~38%,人工种草18%~22%;第4副区和第5副区:水平梯田28%~35%,人工造林40%~46%,人工种草13%~17%,坝地小于5%,水地小于6%。  相似文献   
227.
深化水土保持改革加快治理开发步伐汪上和(水利部黄委会农村水利水土保持局,郑州456003)全国八片水土保持重点地区第十次工作会议在甘肃省定西县召开,是对黄河流域四片二期重点治理工作的极大促进,也是全面宣传推广定西重点治理经验的好机会。定西人民发扬“三...  相似文献   
228.
《中国水土保持》1993,(6):13-16,40
全国水土保持重点治理区之一的三川河流域,十年治理水土流失面积1129km~2,累计治理度达到57.6%,平均治理速度4.1%,其中第一期71条重点小流域治理度达73.4%,年均治理速度5.6%。通过重点治理,全流域人均基本农田达到0.11hm~2,人均经济林0.055hm~2,生态环境初步改善,多种经营迅速发展,国民生产总值每年以7.8%的速率递增,98.7%的贫困户脱贫,年均输入黄河的泥沙量较治理前减少50%以上,治理成效显著。并在实施治理中创造和摸索出一套行之有效的组织领导经验。  相似文献   
229.
精心组织领导放手拍卖“四荒”继续加快小流域治理开发的步伐王文学(山西省人民政府,太原030072)山西省第五次小流域治理工作会议,是在党的十四大提出建立社会主义市场经济体制,各项重大改革措施相继出台的形势下召开的。会议的中心议题,就是按照中央领导同志...  相似文献   
230.
Based on the analysis of chloride ion-induced erosion mechanism of reinforced concrete and the Fick’s second law, a multi-factor model of the chloride ion erosion is established. In this model, the influences of water-cement ratio, humidity, time, temperature, and chloride ion binding capacity of concrete are taken into consideration, and the mathematic solution to the new model is provided by considering the boundary conditions. The new model is verified by analyzing the long-term exposed experiment data. Compared with the traditional model of Fick's second law, the model can indicate the development trend of the structure eroded by chloride and the chloride ion concentration in different depth, and at the same time, it can predicate the chlorine ion concentration on rebar surface in different corrosion periods and the initiation corrosion time of reinforcement.  相似文献   
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