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141.
142.
YONGDONG WANG ODD S.BORGEN BRUCE R.KOWALSKI Laboratory for Chemometrics Center for Process Analytical Chemistry Department of Chemistry BG- University of Washington Seattle WA U.S.A. Present address:Perkin-Elmer Corporation Main Avenue Norwalk CT - U.S.A. 《地理学报(英文版)》1993,(5)
Through theoretical analysis and computer simulation,this short communication comments on theresidual bilinearization(RBL)method and compares it with non-bilinear rank annihilation(NBRA)forthe treatment of second-order calibration with non-bilinear data.It is found that these two methods aremathematically equivalent but have different noise propagation properties.The second-order advantage,namely quantitation in the presence of unknown interferences,can be carried over to non-bilinear dataonly if there exists a net analyte rank(NAR)for the analyte of interest. 相似文献
143.
G.YUN CHANG 《地理学报》1935,(1)
(1) A General Statement.— The west part of Tao-ho which has become ourdominion since the Han Dynasty is still obscure for its geography. It containsnine districts of Kansu Province and two districts of Kokonor Province, andholds an important position in the development of the north-west China. 相似文献
144.
FOREST C.GARNER MARTIN A.STAPANIAN KIRK E.FITZGERALD Lockheed Engineering Sciences Co. E.Flamingo R Las Vegas NV U.S.A. 《地理学报(英文版)》1991,(3)
Multivariate outliers in environmental data sets are often caused by atypical measurement error in a singlevariable.From a quality assurance perspective it is important to identify these variables efficiently so thatcorrective actions may be performed.We demonstrate a procedure for using two multivariate tests toidentify which variable‘caused’each outlier.The procedure is tested with simulated data sets that havethe same correlation structure as selected water chemistry variables from a survey of lakes in the WesternUnited States.The success rates are evaluated for three of the variables for sample sizes of 50 and 100,significance levels of 0.01 and 0.05 and various amounts of mean shift.The procedure works best forhighly correlated variables. 相似文献
145.
苏联气候学的现状及其发展的途径,早就引起了与生产部门的要求和询问直接有关系的气象学者们的注意,因此就在三十年代开始时,对於这个问题就已引起了最广泛的争论。这与第二个斯大林五年计划中在全国范围内所扩大的社会主 相似文献
146.
苏联地理学会(旧称俄国地理学会)是世界上最老的地理学会之一,1845年8月6日在海军上将中Ф.П.李特契的倡议下成立于彼得堡。在俄国地理学会的建立过程中起领导作用的是科学院和海军部。有许多当时的著名学者参加了俄国地理学会,如:教授К.И.阿尔森湼夫,院士К.М.伯尔,海军上将兼旅行家 相似文献
147.
HONG You-chong 《地质通报》2012,31(05):647-652
The fossil specimens discussed in this paper were collected from the grayish green mudstone and shale in the upper part of Lower Member of Middle Triassic Tongchuan Formation (T2t) in Shaanxi Province, China. Venationary feature correlation with old families and taxonomic discussion show that, among them, one specimen can be assigned to a new family - Sunopteridae fam. nov., which includes a new genus and species and can be referred to Order Protorthoptera Handlirsch, 1906 in taxonomic position, thus belonging to a new member of the Tongchuan Entomoassemblage of Shaanxi Entomofauna (belonging to Shaanxi Biota). The discovery of the new family and its new genus and species has certain reference values as follows: ① The discovery of the new family and its new genus and species fills firstly the vacancy in the protorthopterous field of China; ② In the meantime, it fills also the gaps of the valuable Middle Triassic protorthopterous fossil specimens between Late Carboniferous and Late Triassic Epochs in the world; ③ Judging from venationary features and taxonomic position, especially in the course of the formation of the merged vein of M and Cu, it formed a new unique and particular style of merged vein M+Cu. It not only is unique and simple, but also can be distinguished from the above mentioned 10 old families, thus providing important taxonomic evidence. 相似文献
148.
Hemant K. Badola Jitendra S. Butola 《山地科学学报》2005,2(2):173-180
This paper examines the effect of ploughing depths (A -- 60 cm, B -- 45 cm and C -- 30 cm) on the growth and yield of Heracleum candicans Wall (Apiaceae), a threatened medicinal herb of the Himalayan region. This less-explored plant is being suggested as a potential crop for the mountain agriculture. The study was carried out in an orchard in Himachal Pradesh, India at 2500 m altitude, for two successive growth years. During the first year, all plants remained in juvenile state; in the second year, nearly 65 % plants produced flowers only under 60cm ploughing depth. Among its morphological traits, plant height, collar diameter and aboveground flesh weight were found to be strongly correlated (P 〈 0.01) with the belowground biomass during the first year (r =0.968, 0.925 and 0.973, respectively) and during the second year (r=0.945, 0.928 and 0.775, respectively). Increase in the ploughing depth was significantly correlated (P〈0.01) with all growth parameters, including the belowground dry weight, marketable portion of the produce. The belowground biomass (commercial yield; 16.28 Qt/hec) at depth A was about 2.6 and 4.7 times higher than those recorded at depths B and C, respectively. The results clearly justify the importance of deep ploughing and this paper strongly recommends it for economically sustainable cropping. 相似文献
149.
HU Xiaoke JIANG Xiaolu* GUAN Huashi Fishery College Ocean University of China Qingdao P..R.China 《中国海洋大学学报(英文版)》2003,2(1)
1 Introduction Protoplastsserveasabasicandversatiletoolforge neticengineeringandbiochemicalresearchforseveralreasons :theymayregeneratetheirwallsandprovideamodelsystemforstudyingwallbiogenesis ,theirlysisprovidesagentlemeansofpreparingsubcellularor ganelles ,andthemembraneexpositionallowsgeneticmanipulationsinvolvingfusionoruptakeofnucleicacidstobepossible .Theseadvantagesarelessachiev ablewhenusingintactcells (Liciaetal.,1999) .Incomparisonwithlandplantsandunicellularalgae ,on lylimitedrepo… 相似文献
150.
Now GIS is turning into a good tool in handling geographical, economical, and population data, so we can obtain more and more information from these data. On the other hand, in some cases, for a calamity, such as hurricane, earthquake, flood, drought etc., or a decision-making, such as setting up a broadcasting transmitter, building a chemical plant etc., we have to evaluate the total population in the region influenced by a calamity or a project. In this paper, a method is put forward to evaluate the population in such special region. Through exploring the correlation of geographical parameters and the distribution of people in the same region by means of quantitative analysis and qualitative analysis, unit population database (1km× 1km) is established. In this way, estimating the number of people in a special region is capable by adding up the population in every grid involved in this region boundary. The geographical parameters are obtained from topographic database and DEM database on the scale of 相似文献