Mesozoic-Cenozoic thermal history of Turpan-Hami Basin: apatite fission track constraints

Apatite fission track dating is carried out on nine samples collected from the central part (Lianmuqin section) and from both northern and southern margins of Turpan-Hami Basin. The fission-track ages of seven Jurassic samples are distinctly younger than depositional ages. In contrast, the fission-track ages of two Cretaceous samples are older than, or as old as depositional ages. These observations indicate that the Jurassic samples have been annealed or partially annealed, whereas the Cretaceous samples have not been annealed.The further thermal modelling results show that Turpan-Hami Basin experienced a Late Cretaceous period (120-100 Ma) of tectonic uplift with rapid cooling and exhumation of sediments. The samples underwent a Cenozoic period of reburial and re-heating and were exhumed again at 10-8 Ma.     

The evidence of fission-track data for the study of tectonic thermal history in Qinshui Basin

The thermal history of the Qinshui Basin has been studied by using the fission-track analysis of apatite and zircon, integrated analysis of tectonic evolution, magmatic activity and other palaeogeothermal analysis data. Results indicate that the palaeogeothermal gradient between the late-Paleozoic era and the medium-Mesozoic era is relatively low and the palaeogeothermal gradient in the late-Mesozoic is up to 5.56癈/100 m in the middle, and the values are relatively higher in the north and south margins of the basin, reaching over 8.00℃/100 m, which indicates that there was an anomalous tectonic thermal event in the thermal history of Qinshui Basin. This event happened in 110-140 Ma, and the main peak value was between 120 and 140 Ma. This anomalous tectonic thermal event is controlled by the strengthening thermal mobility of the lithosphere and magmatic intrusion. The maturity of the Permo-Carboniferous coal series mainly was controlled by this anomalous thermal field. The apatite fission track date of samples across the basin shows that a rapid tectonic uplifting with cooling existed 26.2-11.5 Ma ago and the upliftings in the north and south of the basin happened earlier than that in the middle. The Permo-Carboniferous strata had been completely annealed in the early 50 Ma, palaeotemperature over 125℃. Since then, especially from Oligocene-Miocene epoch, the strata which experienced large-scale tectonic upliftings with rapid cooling have been kept out of the annealing belt (70-125℃) in a relative low temperature environment. The late Mesozoic tectonic thermal event control hydrocarbon production peak (late Jurassic to early Cretaceous period) of Permo-Carboniferous strata in Qinshui Basin. When the strata experienced upliftings with rapid cooling since Oligocene-Miocene epoch, the hydrocarbon generation of coal series had stopped.     

对任务型语言教学模式的探讨与体会

借助教学实验探讨在本科院校英语专业学生的精读教学课堂里实施基于任务的教学模式的必要性和可行性。实验结果和统计分析表明:两组学生对语言知识的掌握和语言能力方面没有显著意义上的差别,但实验组学生在语言行为方面要优于对照组。他们不仅获得了语言知识,同时还表现出较好的跨文化交际能力。     

变位四履带足机器人行走机构的越障性能研究

对自行研制的变位四履带足机器人行走机构的越障性能进行分析，并与普通双履带行走机构的越障性能进行比较，证实了此行走机构在越障性能上的优越性。     

Zhang-Xuan thermal uplift and its genesis

Variousformsofcrustdeformationaccompany ingthelithospherethinninginNorthChinasincethe Mesozoichavedrawnattentionfrommanygeologists.Therecordsofdeformationandthermalevolutionary historyindifferentperiodsarequitecompletefortwo upliftbelts,whichlocatedrespectivelyatthenearE WstrikingYanshanMt.intersectingwiththeNNE strikingTaihangMt.andDaHigganMt.risingin theMesozoic,nowtheZhangjiakou Xuanhuaand Chifeng Harqinareas.Theformerareahasbeenafo cusofattentionforitsgoldfield[1],anditstectonic se…     

电子轨道角动量公式的一种简单推导方法

以氢原子为例，根据电子运动的波函数Ψ的径向部分R(r)所遵循的微分方程，与电子饶核转动无关这一特点，经过简单的初等计算，就可以求出电子轨道角动量公式。     

基于贝叶斯方法的多Agent强化学习

在多agentss强化学习（MARL）的研究中，很多都是强调MARL算法收敛于期望平衡解。然而，对于标准的强化学习，该过程需要对策略空间的充分探测，而且探测还经常受到惩罚或错失了良机。在多agents系统中，由于agents之间的协作使该问题更加复杂。为此，提出了在MARL用贝叶斯模型来进行最优探测，该模型与标准的RL模型不同，它将对agent的动作是如何影响其它agents的行为进行推理。同时，还给出了如何对最优贝叶斯探测进行处理以获得理想的结果，并通过与其它算法的比较来说明用贝叶斯方法的可行性.     

多传感器跟踪的航迹关联

多传感器目标跟踪是信息融合技术在目标跟踪领域的应用范例,航迹关联是其中的关键技术之一.提出先用模糊C-均值算法对点迹聚类,然后根据聚类的结果定义航迹关联质量,选择航迹关联质量大的为关联对.这样使关联同时能考虑当前和历史航迹,提高了关联正确率.最后把多传感器航迹融合,得到了很好的跟踪效果.仿真结果表明,该算法是确实有效的.     

捷联惯性导航系统飞行轨迹数据生成与惯性器件建模

由于很难获得全面真实的导航飞行轨迹数据，而各类导航系统软硬件性能测试验证又必须要有飞行轨迹数据和惯性器件的输出参数。为此，作者提出了一种生成测试用飞行轨迹，并能为惯性器件建模的解析式思想。用这种思想产生的飞行轨迹数据和惯性器件的模型，在硬件平台软硬件系统测试验证中得到了成功地应用，取得了很好的效果。     

双波段红外传感器目标跟踪集中式航迹起始方法

航迹起始做为多目标跟踪技术中的关键问题，得到了广泛的重视和研究。雷达跟踪系统的航迹起始技术已经非常成熟、完善了。然而对于双波段红外传感器跟踪系统，由于各个波段的红外传感器对特定的目标表现出不同的检测特性。在研究雷达跟踪系统时采用的目标探测概率趋近1的假设是不成立的。所以，将分布式航迹起始，然后进行航迹互联的方法原封不动的应用到双红外系统中是否可行需要进一步讨论。提出了一种适合于双波段红外传感器的集中式航迹起始方法，理论推导和仿真试验都表明与分布式航迹起始方法相比，在稀疏噪声、传感器探测概率不高的情况下，这种集中式航迹起始方法具有更好的性能。