Estimation of solar illumination on the Moon: A theoretical model

The solar illumination conditions on the lunar surface represent a key resource with respect to returning to the Moon. As a supplement to mapping the solar illumination by exploring data, lighting simulations using high-resolution topography could produce quantitative illumination maps. In this study, a theoretical model is proposed for estimating the solar illumination conditions. It depends only on the solar altitude and topographical factors. Besides the selenographic longitude and latitude, the former is determined by the selenographic longitude and latitude at the subsolar site, the geocentric ecliptical latitude, and the dimensionless distance of the Sun–Moon relative to 1 AU, which are function of time. The latter is determined by comparing the elevations in solar irradiance direction within 210 km in which the topography might shadow the behind sites to the critical elevations determining whether the behind sites are shadowed or not. Compared to Zuber's model, the model proposed in this study is simpler and easier for computing. It is parameterized with selenographic coordinates, elevations, and time. With high-resolution topography data, the solar illumination conditions at any selenographic coordination could be estimated by this model at any date and time. The lunar surface is illuminated when the solar altitude is non-zero and all the elevations within 210 km in solar irradiance direction are lower than the critical elevations. Otherwise it would be shadowed.     

中国大陆及周边地区的水平应变场

推导并建立了块体的两种弹性运动方程：块体的整体旋转与均匀应变方程和块体的整体旋转与线性应变方程. 应用统计学原理,使用西域、青藏和华北块体上的GPS站速度数据,对这两种弹性运动方程与刚体运动方程模拟块体站速度的无偏性和有效性进行了统计检验. 检验结果表明,块体的整体旋转与线性应变方程是描述块体运动的最优模型. 将中国大陆划分为10个块体,应用块体的整体旋转与线性应变方程和块体上的GPS站速度估计了各个块体上的旋转与应变参数,按照1°×1°的间距计算了中国大陆及周边地区上1005个点的应变参数,分析了中国大陆及周边地区应变场的基本特征. 用本文方法得到的主压应变方向与地质学方法和测震学方法得到的主压应力轴方向具有很好的一致性(华南块体除外).     

基于格网划分的海量数据Delaunay三角剖分

提出基于格网划分、面向海量数据的Delaunay三角剖分方法,它首先把数据集划分为若干格网块,按照格网划分的逆序对每个格网块采用基于自适应格网划分的分割-合并算法进行Delaunav三角剖分,把格网块Delaunay三角网中不受边界影响的三角形进行存储并释放内存,然后顺序合并相邻格网块Delaunav三角网,形成全局或类全局Delaunay三角网.该方法对计算机硬件配置要求较低,适合于并行处理,可以实现面向海量数据的Delaunay三角剖分.     

西藏多龙超大型铜(金)矿集区成矿模式与找矿方向

本文通过对比研究,认为多龙矿集区内斑岩型、隐爆角砾岩筒型、浅成低温热液型矿床等三种共生矿床类型属同一岩浆-热液成矿系统的产物,空间上分别位于这一成矿系统低位域、低位域顶部及高位域,其空间相对位置可作为成矿系统内相关类型矿床的勘查找矿标志。基于深部岩体的识别和矿田构造格架的建立,完善了多龙矿集区深部岩浆在地壳浅部就位和成矿的过程,构建起多龙矿集区区域成矿模式。根据该成矿模式,多龙矿集区尕尔勤、地堡那木岗及矿集区南东部等地区是下一步开展矿产勘查的有利区块;矿体形成后可能被成矿后构造错断,这一认识可以作为寻找深部隐伏矿体的勘查依据。最后指出这一成矿模式对区域找矿方向的指示意义,认为区域找矿预测中应加强班公湖-怒江成矿带中生代古陆边缘岩浆弧型斑岩-浅成低温热液成矿系统剥蚀与保存机制的研究;用于识别深部岩体的非常规找矿新方法可应用于斑岩相关矿床的评价。     

北京山区单沟洪水模型预警系统研究 ——以孙胡沟为例

山洪是山区中影响范围广,人员伤亡较大的一类地质灾害。针对山洪预警模型,国内外学者从多个角度对其进行过研究,研究区域多为大流域,方法多为雨量临界值预警。为了建立一套适用于北京山区小流域的山洪预警模型,本文研究了小流域单沟洪水模型预警在系统,此系统是基于充分的野外地质调查,在获得详细的沟域地质及土地利用数据后,利用合理的数学模型对流域内的降雨所产生的洪水产汇流过程进行全过程模拟,并对汇流过程中可能产生的灾害进行预警预报的一个系统。此单沟洪水模型具有精度高,计算结果准确的特点,其相应的预警系统能够对小范围居民区等重要建构筑物进行灾害预报,并预估人员撤离的安全时间,对实际的防灾减灾工作具有重要意义。     

Comparison of hydrological models for use in climate change studies: A test on 241 catchments in West and Central Africa

The present work reports on the study and the comparison of the performance of three “Génie rural” (GR) and two Water Balance (WB) models. The calibration and robustness performances are analysed in the light of the hydro-climatic conditions. The study shows that the GR models are much more efficient and robust than the WB models. The behaviour of calibration performance as a function of hydroclimatic variables varies according to the model and goodness-of-fit criteria (GOFC). The GR models are more robust in terms of NSE(Q) and NSE(√Q) and the WB models in terms of KGE. For more robustness of the models, it is better to transfer the parameters to wetter periods or periods with a lower Potential EvapoTranspiration (PET) than the calibration period. For a loss of robustness of less than 20% for GR and 30% for WB, the variation between calibration and rain validation/PET periods must be around ±15%/±1.5%.     

开鲁盆地陆西凹陷热埋藏史研究

本文通过对有机质干酪根类型的分析，重新确定了陆面凹陷时间温度指数（ＴＴＩ）值计算的基准温度及古地温梯度，对凹陷内沉积厚度大的地方进行了沉积构造史的恢复，并建立了凹陷热埋藏史模式．据此计算了凹陷内部分ＴＴＩ值．通过研究，指出了目前对凹陷进行石油勘探的有利生油岩层位．     

Separating wheat from chaff: Diatom taxon selection usingan artificial neural network pruning algorithm

This study addresses the question of what diatom taxa to includein a modern calibration set based on their relative contribution in apalaeolimnological calibration model. Using a pruning algorithm for ArtificialNeural Networks (ANNs) which determines the functionality of individual taxa interms of model performance, we pruned the Surface Water Acidification Project(SWAP) pH-diatom data-set until the predictive performance of thepruned set (as assessed by a jackknifing procedure) was statistically differentfrom the initial full-set. Our results, based on the validation at each5% data-set reduction, show that (i) 85% of the taxa canbe removed without any effect on the pH model calibration performance, and (ii)that the complexity and the dimensionality reduction of the model by theremoval of these non-essential or redundant taxa greatly improve therobustness of the calibration. A comparison between the commonly usedmarginal criteria for inclusion (species tolerance andHill's N2) and our functionality criterion shows that the importance ofeach taxon in an ANN palaeolimnological model calibration does not appear todepend on these marginal characteristics.     

沙漠边缘地区苹果“两高一优”栽培管理技术规范

通过对沙漠边缘地区影响苹果高产高效和优质的生态因子的综合评估，在多项生产试验的基础上，提出了该区苹果幼树期、结果期两个阶段“两高一优”栽培管理技术规范。     

绿洲型城市生态经济系统持续发展仿真研究

本文从限制绿洲型城市发展的水、土因素出发，分析了自然资源、环境条件与社会经济发展之间的相互关系，运用系统动力学方法建立了绿洲型城市生态经济系统持续发展的动态仿真模型，并以新疆自治区奎屯市为例，对该模型作了模拟调试及多方案的仿真实验，有关结果对绿洲型城市发展提供了科学依据。