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21.
Zhang Qing-hua Li Jian ke Qu Yuan yuan First Institute of Oceanography State Oceanic Administration Qingdao China Key Laboratory of Marine Science Numerical Modeling State Oceanic Administration Qingdao China 《水动力学研究与进展(B辑)》2001,(3)
1 . INTRODUCTIONForthelarge scaleoceanicflow ,peopleusuallyseekthesolutionsfromthequasi geostrophicvortici tyequationderivedfromtheperturbationbyusingRossbynumberεasalittleparameter.Animportantapproximationwhendeductingvorticityequationinthelayeredseawat… 相似文献
22.
Marie-Axelle Granié Thierry Brenac Marie-Claude Montel Marine Millot Cécile Coquelet 《Accident; analysis and prevention》2014
The objective of this experimental study is to identify the differentiation made by pedestrians, in their crossing decision, between various urban environments, notably in terms of perception of walking pleasantness and safety. This experiment further aims to identify the environmental features that pedestrians take into account and the inferences they develop and use to explain their road crossing decision. Sets of photographs presenting five different environments (city center, inner suburbs, public housing in the outskirts, commercial zone in the outskirts and countryside) were presented to 77 participants divided up into three age groups (pre-adolescents, young and middle adults). Their decision to cross or not, their perception of pleasantness and safety, and the elements they take into account to make a decision were collected for each environment presented. The quantitative results show the pedestrians’ perceptions of the pleasantness and safety of public spaces, in terms of walking, largely vary with urban environments. Moreover, the crossing decision significantly varies according to the environment. Pedestrians were significantly more inclined to take the decision to cross in city center than in the other sites presented. The qualitative analysis of the interviews shows that the presence and function of the buildings, the quality of the sidewalks and the marked parking spaces are key factors to explain their crossing decision, by enabling them to infer the density of pedestrians and traffic and the vehicle speed. 相似文献
23.
采用等离子喷涂工艺在高锰铝青铜基体上制备了 Al2O3-13%TiO2和Cr2O3·5SiO2·3TiO2两种耐冲蚀复合涂层,利用扫描电子显微镜(SEM)、激光扫描显微镜(LSM)等手段观察分析了两种涂层的组织形貌,测试了两种涂层的显微硬度和结合强度,用电化学测量和失重测量分别研究了两种涂层在3.5%NaCl溶液中的电... 相似文献
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25.
本文基于克希霍夫成像理论,对共反射面元(CRS)叠加方法进行了深入分析,阐述了等旅行时面共反射面元叠加方法(CRS-OIS)原理及其测试效果。指出CRS-OIS是对于传统共反射面元叠加方法的重要改进,它简化了传统CRS叠加方法,可以同时得到信噪比大幅度提高的叠前道集与零炮检距成像剖面。该方法首次被用于南海深水二维地震数据处理,处理结果表明基底与莫霍面的成像品质得到明显改善,提高了剖面的可解释性。 相似文献
26.
XIAChang-shui QIAOFang-li ZHANGQing-hua YUANYe-li 《水动力学研究与进展(B辑)》2004,16(5):537-543
A free surface quasi-global ocean circulation model, Princeton Ocean Model (POM), was adopted to simulate the climatological circulation. The horizontal resolution of the model was 1/2~X 1/2~ with 16 vertical sigma layers. The initial temperature and salinity fields of the model were interpolated from the Levitus data, and the COADS(Comprehensive Ocean-Atmosphere Data Set ) monthly mean SST and wind fields were used as the surface forcing. The integral time length is 6a. The main general circulation components such as the equatorial current, the equatorial undercurrent, the south and north equatorial currents, the Antarctic Circumpolar Current (ACC), the Kuroshio and the Gulf Stream were well reconstructed. The volume transports of PN section and ACC agree well with the estimations on field survey. Up to now there is no global or quasi-global circulation model results using POM in literature. Our results demonstrate that POM has sound ability to simulate the coastal circulation as well as the general ocean circulation. And this result can provide open boundary conditions for fine resolution regional ocean circulation models. 相似文献
27.
Yu Wei-dong Key Laboratory of Marine Science Numerical Modeling State Oceanic Administration First Institute of Oceanography Qingdao China 《水动力学研究与进展(B辑)》2001,(3)
1 . INTRODUCTIONItisknownthatthetropicalocean atmospheresystemissensitivetosmallfluctuationsintheseasurfacetemperature (PalmerandMansfield ,1 986) .Thissensitivitystemsformthesimilarityinscalesofmotionbetweenatmosphereandoceannearthee quator.Inthelasttwodecad… 相似文献
28.
Cui Mao chang Institute of Oceanology Chinese Academy of Sciences Qingdao China Key Laboratory of Marine Science Numerical Modeling State Oceanic Administration Qingdao China Qiao Fang li Key Laboratory of Marine Science a 《水动力学研究与进展(B辑)》2001,(3)
1 . INTRODUCTIONJustaslightcanbedecomposedinto 7colorsandmusicinto 7notes,thecomplexverticalprofilesofoceandynamicalfactorsandsoundspeedcanalsobedecomposedintoaseriesofnormalmodes[1~ 5] .Basedonthisfact,intheearly 1 980sAmericaactu alizedtheOceanicAcousticTomog… 相似文献
29.
Qiao Fang li Xu Xiao biao Tang Yu xiang Zhao Wei Labortary of Marine Science Numerical Modeling State Oceanic Administration Qingdao China 《水动力学研究与进展(B辑)》2001,(3)
1 . INTRODUCTIONTheYellowSea (Fig .1 ) ,locatedinthemiddlelatitude,isoneofthemosttypicalsemi enclosedseasintheworld ,withthemaximumdepthof 80mFig .1 TopographyoftheYellowSeaandtheEastChinaSeaintheYellowSeatrough .ItisconnectedwiththePacificOceanthroughtheECS .The… 相似文献
30.
Competition of urea with oilseed proteins in ruminant feeding depends primarily on economic relationships between these ingredients,
cost of energy sources and proper feed formulation. A general summary of the more important factors to consider in replacing
protein with nonprotein nitrogen in ruminant feeds is presented. Estimated urea utilization in the U.S. grew at a 15.5% compound
annual rate from 1962 to 1966. From 1966–1969, usage increased at a 5% compound annual rate. Approximately 650,000 tons of
urea were used by the U.S. Feed industry in 1969. Urea usage is expected to continue to grow in the United States. The high
cost of energy sources in Western Europe will tend to slow its use by the feed industry of that area. In general, competition
of urea with oilseed proteins will be greatest with heavy grain feeding of cattle, low cost grains and high priced oilseed
meals.
One of 16 papers being published from the Symposium, “Oilseed Processors Challenged by World Protein Needs,” presented at
the ISF-AOCS World Congress, Chicago, September 1970. 相似文献