SIMULATED THERMAL ALTERATION OF STEROLS AND KETO-ALCOHOLS IN MARINE SEDIMENTS OF THE OKINAWA TROUGH

Compositional data on the sterol and alcohol fractions isolated from deep-sea marine sediments from the Okinawa Trough were obtained to determine the relative contribution from. marine and terrestrial inputs. Following extraction, the sterol plus alcohol fraction was isolated by layer chromatography, derivatized with BSTFA and then analysed by capillary GC and GC-MS. A suite of C26-C29 stenols and stanols and C30-C32 keto - alcohols were identified in the sediments. The thermal stability of the compounds in these sediments was studied by heating portions of the surface sediment in glass tubes fpr 16 hours at temperatures from 50℃ to 200℃.The C27 stanol/stenol ratio increased when temperatures went up to 175℃ , but the distribution of C30-C32 Keto - alcohols remained unaffected. At 200℃ most of the sterols and Keto - alcohols were destroyed.     

山东省侏罗－白垩纪岩石地层清理意见

运用多重地层划分进行山东省地层清理研究中，对中生代侏罗－白垩纪岩石地层划分得出一些新认识。提出蒙阴盆地及其周围的汶南组与淄博地区的三台组属同物异名，故泣南组名应废弃。山东省侏罗系只有坊子组、三台组一个地层序列，将二者合建淄博群。并按岩石地层划分原则，以岩石组合特征为依据，对白垩系进行了划分、对比，建立了区域地层格架，理顺了莱阳群、青山群、大盛群、王氏群各单位间相互关系，避免了同名异物和同物异名等现象，４个群共划分组级单位２２个。     

Corner points localization in electronic topographic maps with deep neural networks

Digitized topographic maps normally have to go through the geometric calibration before practical utilization. Nowadays, the reference points for the calibration are still manually assigned. Corner points (graticule intersections) in a map are usually good candidates in favor of the reference points. This paper proposes an algorithm for automatically locating the corner points in the electronic topographic maps by detecting the specific rectangle objects in the map corners. It assigns the probabilities to each row and column in the region of interests (RoIs) to provide information regarding the location of the objects. In order to facilitate the object detection with high level visual features, the deep neural networks (DNNs) are employed in the proposed algorithm. For the object proposal, the sliding window scheme is adopted. The experimental results indicate that the proposed approach outperforms the conventional bounding-box regression method in both detection and localization accuracy. For the proposed algorithm, the average F1 score in the object detection is 0.91, which is 12% higher than the conventional model. The mean Euclidean distance between the predicted corner points and the ground-truth by the proposed algorithm is 2.22 pixels, 35.8% lower compared with the regression based model.     

高美古空气湿度的初步分析

给出丽江高美古天文候选点两年的湿度观测结果与宾川３００２ｍ山峰的比较,初步分析了湿度对天文可用时间及视宁度的影响。     

金阳底苏会东大梁子铅锌矿床内闪锌矿微量元素标型特征及其研究意义

探讨了底苏和大梁子铅锌矿床闪锌矿的微量元素标型特征及其意义。研究结果认为底苏、大梁子铅锌矿床属沉积改造层控矿床，其成矿温度为中低温。     

北京城市舒适性、差异性与创新能力的关系

城市舒适性对城市创新发展有重要影响,但对大都市区内部舒适性及差异性对城市创新能力的影响研究较少。以北京市为研究区域,利用耦合协调度模型和多元线性回归模型分析城市舒适性与创新能力的关系。研究发现：① 北京市总体舒适性分布特点是以中心城区为核心,随着距中心城区距离增加,城区的舒适性水平逐渐降低。② 北京生态环境舒适性呈现从西北地区向东南地区逐渐递减的特点,而人工环境和社会氛围的舒适性由中心向四周地区递减,各区的舒适性水平在空间分布上呈集聚状态,高-高型聚类集中在东城区、西城区、朝阳区、海淀区及丰台区,形成北京市“高舒适性”区域。③ 结合耦合协调度模型发现北京市除平谷区、密云区和延庆区,其他城区目前均处于高水平耦合阶段,海淀区、东城区、西城区、朝阳区、丰台区的创新能力和舒适性发展耦合协调度较高,但北京市各区也存在舒适性与城市创新之间发展相对滞后问题。④ 北京城市舒适性与创新能力存在正相关关系,但不同舒适性要素对创新能力的作用不同,文化教育条件对城市创新能力的影响强度最大,交通便利性和社会氛围对创新能力的作用次之。政策建议是要推进文化教育、交通条件等人工舒适性水平的相对均衡发展,提高各区的城市舒适性,以城市舒适性推动创新能力的提升。     

龙岗金龙顶子火山空降碎屑物数值模拟及概率性灾害评估

空降碎屑物为爆炸式火山喷发产生的一种重要的灾害类型,数值模拟已成为一个快速有效地确定火山灰扩散和沉积范围的方法。本文根据改进的Suzuki(1983)二维扩散模型,编写了基于Windows环境下的火山灰扩散程序。通过对前人资料的分析,模拟了龙岗火山群中最新火山喷发——金龙顶子火山喷发产生的空降碎屑物扩散范围,与实测结果具有很好的一致性,证实了模型的可靠性和参数的合理性。根据该区10年的风参数,模拟了7021次不同风参数时金龙顶子火山灰的扩散范围,以此制作了火山灰沉积厚度超过1cm和0.5cm时的概率性空降碎屑灾害区划图。本文的研究可为龙岗火山区火山危险性分析和灾害预警与对策提供重要的科学依据。     

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Exploration Opportunity Search of Near-earth Objects Based on Analytical Gradients

The problem of search of opportunity for the exploration of near-earth minor objects is investigated. For rendezvous missions, the analytical gradients of the performance index with respect to the free parameters are derived using the variational calculus and the theory of state-transition matrix. After generating randomly some initial guesses in the search space, the performance index is optimized, guided by the analytical gradients, leading to the local minimum points representing the potential launch opportunities. This method not only keeps the global-search property of the traditional method, but also avoids the blindness in the latter, thereby increasing greatly the computing speed. Furthermore, with this method, the searching precision could be controlled effectively.