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91.
一、工程概况
济南市天成新居廉租房工程项目地处济南市天桥区天成路东侧,北侧紧邻胶济铁路,东侧为多层居民住房,南侧为天茂路。 相似文献
92.
Verifying Fossil-Fuel Carbon Dioxide Emissions Forecasted by an Artificial Neural Network with the GEOS-Chem Model
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In this study, the authors developed an en- semble of Elman neural networks to forecast the spatial and temporal distribution of fossil-fuel emissions (ff) in 2009. The authors built and trained 29 Elman neural net- works based on the monthly average grid emission data (1979-2008) from different geographical regions. A three-dimensional global chemical transport model, God- dard Earth Observing System (GEOS)-Chem, was applied to verify the effectiveness of the networks. The results showed that the networks captured the annual increasing trend and interannual variation of ff well. The difference between the simulations with the original and predicted ff ranged from -1 ppmv to 1 ppmv globally. Meanwhile, the authors evaluated the observed and simulated north-south gradient of the atmospheric CO2 concentrations near the surface. The two simulated gradients appeared to have a similar changing pattern to the observations, with a slightly higher background CO2 concentration, - 1 ppmv. The results indicate that the Elman neural network is a useful tool for better understanding the spatial and tem- poral distribution of the atmospheric C02 concentration and ft. 相似文献
93.
一个两时间层分裂显格式海洋环流模式(MASNUM)及其检验 总被引:1,自引:0,他引:1
HAN Lei 《海洋学报(英文版)》2014,33(11):11-35
A two-time-level, three-dimensional numerical ocean circulation model(named MASNUM) was established with a two-level, single-step Eulerian forward-backward time-differencing scheme. A mathematical model of large-scale oceanic motions was based on the terrain-following coordinated, Boussinesq, Reynolds-averaged primitive equations of ocean dynamics. A simple but very practical Eulerian forward-backward method was adopted to replace the most preferred leapfrog scheme as the time-differencing method for both barotropic and baroclinic modes. The forward-backward method is of second-order of accuracy, computationally efficient by requiring only one function evaluation per time step, and free of the computational mode inherent in the three-level schemes. This method is superior to the leapfrog scheme in that the maximum time step of stability is twice as large as that of the leapfrog scheme in staggered meshes thus the computational efficiency could be doubled. A spatial smoothing method was introduced to control the nonlinear instability in the numerical integration. An ideal numerical experiment simulating the propagation of the equatorial Rossby soliton was performed to test the amplitude and phase error of this new model. The performance of this circulation model was further verified with a regional(northwest Pacific) and a quasi-global(global ocean simulation with the Arctic Ocean excluded) simulation experiments. These two numerical experiments show fairly good agreement with the observations. The maximum time step of stability in these two experiments were also investigated and compared between this model and that model which adopts the leapfrog scheme. 相似文献
94.
利用时序InSAR技术的优势,以新疆WLL水库大坝为研究对象,使用31幅Sentinel-1A影像,采用StaMPS
方法对其进行形变监测,得到大坝及周边区域的形变结果,并从内、外符合精度两个方面进行精度验证。结果表明,
研究区域PS点平均形变速率标准差区间为0.3~3.1mm/a;StaMPS与SBAS形变速率中误差为±5.7mm;与大
坝二等水准监测成果比较,垂直形变速率中误差为±5.0mm,垂直累积形变量中误差为±10.2mm。从而证明
StaMPS方法在大坝形变监测应用中的可行性。 相似文献
95.
LIU Bin LIU Jianzhong ZHANG Guangliang LING Zongcheng ZHANG Jiang HE Zhiping YANG Benyong ZOU Yongliao 《中国地球化学学报》2014,33(1):86-94
In 2013, Chang'E-3 program will develop lunar mineral resources in-situ detection. A Visible and Near-infrared Imaging Spectrometer (VNIS) has been selected as one payload of CE-3 lunar rover to achieve this goal. It is critical and urgent to evaluate VNIS' spectrum data quality and validate quantification methods for mineral composition before its launch. Ground validation experiment of VNIS was carried out to complete the two goals, by simulating CE-3 lunar rover's detection environment on lunar surface in the laboratory. Based on the hyperspectral reflectance data derived, Correlation Analysis and Partial Least Square (CA-PLS) algorithm is applied to predict abundance of four lunar typical minerals (pyroxene, plagioclase, ilmenite and olivine) in their mixture. We firstly selected a set of VNIS' spectral parameters which highly correlated with minerals' abundance by correlation analysis (CA), and then stepwise regression method was used to find out spectral parameters which make the largest contri- butions to the mineral contents. At last, functions were derived to link minerals' abundance and spectral parameters by partial least square (PLS) algorithm. Not considering the effect of maturity, agglutinate and Fe~, we found that there are wonderful correlations between these four minerals and VNIS' spectral parameters, e.g. the abundance of pyroxene correlates positively with the mixture's absorption depth, the value of absorption depth added as the in- creasing of pyroxene's abundance. But the abundance of plagioclase correlates negatively with the spectral parame- ters of band ratio, the value of band ratio would decrease when the abundance of plagioclase increased. Similar to plagioclase, the abundance of ilmenite and olivine has a negative correlation with the mixture's reflectance data, if the abundance of ilmenite or olivine increase, the reflectance values of the mixture will decrease. Through model validation, better estimates of pyroxene, plagioclase and ilmenite's abundances are given. It is concluded that VNIS has the capability to be applied on lunar minerals' identification, and CA-PLS algorithm has the potential to be used on lunar surface's in-situ detection for minerals' abundance prediction. 相似文献
96.
97.
98.
水下溢油数值模拟研究 总被引:1,自引:0,他引:1
基于Lagrange积分法和Lagrange粒子追踪法建立了一个水下溢油数值模型。该溢油模型由两个子模型组成:羽流动力模型和对流扩散模型,其中羽流动力模型用以模拟溢油的喷发阶段和浮力羽流阶段;对流扩散模型用以模拟溢油的对流扩散阶段。通过数值实验,结合实验室水槽实验和水下溢油现场实验的观测资料进行模型验证。实验结果表明,模拟结果与观测资料一致性较好,从而验证了本文溢油模型的合理性和准确性;羽流动力模型为对流扩散模型提供源,海流、海水的垂向密度结构和油滴的直径分布是影响溢油在对流扩散阶段运动和分布的主要因素。 相似文献
99.
100.
文章主要介绍了ZHDN-SDR 150A 型高频声波钻机设计及其验证测试,为该钻机应用于污染场地调查和治理提供理论依据和技术指导。论文阐述了钻机总体设计思路及主要性能参数指标,系统分析了高频声波动力头、钻机主体、配套钻具结构设计及其技术创新。该钻机在两种不同地层进行了验证测试,各项测试指标均达到设计要求。将验证测试结果与国内外同类钻机对比表明,ZHDN-SDR 150A型钻机主要性能参数与关键装置已处于国内先进和国外并跑水平。该型钻机在振动频率、地层适用性、钻具使用寿命等方面优势显著,但是存在过高温度运行条件下钻进效率降低、智能自动化水平不足的问题,需进一步研发耐高温强硬度新材料和改进远程无线操控系统。 相似文献