山东省唐王寨上寒武统崮山组沉积环境及竹叶状灰岩的多成因分析

华北地台上寒武统崮山组出现了大量的竹叶状灰岩。通过对山东唐王寨剖面崮山组的系统研究,识别出页岩、疙瘩状泥晶灰岩、泥质条带泥晶灰岩、薄层状泥晶灰岩、生物扰动泥晶灰岩、颗粒质（生物碎屑）泥岩-泥质颗粒岩、含交错层理鲕粒灰岩及竹叶状灰岩8种岩石类型,这些岩石类型组成了页岩盆地、深潮下带及浅潮下带岩石组合。竹叶状灰岩中砾屑和基质的特征及其沉积序列,表明砾屑和基质的来源多样并且在不同的沉积环境中其成因具有多样性。据此总结出崮山组竹叶状灰岩具有4种可能的成因类型：1）竹叶状灰岩中砾屑和基质可能均为原地形成或者仅有短距离的搬运过程;2）竹叶状灰岩中砾屑和基质可能均为近岸形成并经历了长距离的搬运过程,或者竹叶状灰岩的沉积环境经历了海平面的突然升高;3）竹叶状灰岩中基质可能来源于近岸未固结的鲕粒和生物碎屑及原地的灰泥,与原地破碎生成的砾屑和灰泥等混合沉积;4）竹叶状灰岩中砾屑可能来源于远岸的固结的泥晶灰岩,并经搬运作用与原地未固结的灰泥及骨架颗粒等基质混合沉积。     

A comparative approach to modelling multiple urban land use changes using tree-based methods and cellular automata: the case of Greater Tokyo Area

Urban multiple land use change (LUC) modelling enables the realistic simulation of LUC processes in complex urban systems; however, such modelling suffers from technical challenges posed by complicated transition rules and high spatial heterogeneity when predicting the LUC of a highly developed area. Tree-based methods are powerful tools for addressing this task, but their predictive capabilities need further examination. This study integrates tree-based methods and cellular automata to simulate multiple LUC processes in the Greater Tokyo Area. We examine the predictive capability of 4 tree-based models – bagged trees, random forests, extremely randomised trees (ERT) and bagged gradient boosting decision trees (bagged GBDT) – on transition probability prediction for 18 land use transitions derived from 8 land use types. We compare the predictive power of a tree-based model with multi-layer perceptron (MLP) and among themselves. The results show that tree-based models generally perform better than MLP, and ERT significantly outperforms the three other tree-based models. The outstanding predictive performance of ERT demonstrates the advantages of introducing bagging ensemble and a high degree of randomisation into transition probability modelling. In addition, through variable importance evaluation, we found the strongest explanatory powers of neighbourhood characteristics for all land use transitions; however, the size of the impacts depends on the neighbourhood land use type and the neighbourhood size. Furthermore, socio-economic and policy factors play important roles in transitions ending with high-rise buildings and transitions related to industrial areas.     

Knowledge-guided consistent correlation analysis of multimode landslide monitoring data

A novel method called knowledge-guided spatio-temporal consistent correlation analysis (KSTCCA) was developed to discover reliable deformation features induced by multiple factors based on multimode landslide monitoring data. Compared to conventional approaches, KSTCCA integrates both temporal and spatial correlation analysis to improve the consistency of deformation patterns and capture the spatio-temporal heterogeneities in multimode monitoring data. KSTCCA considers both the landslide deformation mechanisms and the relationships between different influential factors as knowledge. Moreover, the method extracts the morphological structures of monitoring curves based on a seven-point approach and identifies knowledge rules using the k-means clustering method. Under the guidance of prior knowledge, a spatial correlation analysis is conducted based on support vector regression, and a temporal correlation analysis of the time lag is carried out based on the morphological structure features. Finally, three kinds of typical monitoring data, including deformation, rainfall, and reservoir water level data collected in the Baishuihe landslide area, China, are used for experimental analysis to verify the validity of the proposed method.     

An analysis on location factors affecting the spatial distribution of Shanghai land values

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城市测量控制网的设计

本文以优化设计的实施性为目的,采用模拟法进行二类及三类城控网的设计。二类设计在算法上采用矩阵反演公式来提高计算速度及保证结果的优良性;三类设计（加测元素最佳位置的确定）使用敏感测度,并顾及周围边长精度的改变状况,构成多目标函数的最优数学模型,最后对大型网进行了详细的分析和说明。     

Rock-mass characterization using intrinsic and scattering attenuation estimates at frequencies from 400 to 1600 Hz

Intrinsic and scatteringS-wave quality factors (Q ) were estimated using the Multiple Lapse Time Window Analysis (MLTWA) for microseismic events (M<–1) with source-sensor distances of 45 to 120 m, associated with an excavation at 630 m depth in Strathcona Mine, Sudbury, Canada. Additional information on the rock mass was provided by underground structural mapping data. IntrinsicQ values, at 800 Hz, were on the order of 140, similar to quality factor values obtained in previous studies using Spectral Decay and Coda-Q methods (120 to 170). The scattering quality factor at this frequency was about 520. An observed frequency dependence of the scattering attenuation suggested that a decrease in the density of scatterers, with scale lengths on the order of 2 m, exists at the site. Characteristic fracture scale lengths were considered to range from 4 to 6 m as identified in the mapping data. These observations were supported by the increase in scattering found for seismic waves with frequencies less than 1000 Hz. By assuming that the identified scatters are characteristic faults, these scatterers can then be considered to increase nonsimilar behavior in source scaling. Overall, our results suggest that MLTWA provides a practical method for remotely characterizing the quality of a rock mass when visual observations are not attainable.     

水声通信网及其多址接入技术

随着世界各国海洋开发步伐的加快,对水下传感器网络、水下监视系统、水声预警网络的需求愈来愈迫切,海洋水声通信网络的研究成了世界范围内的研究热点.水声通信网研究面临的主要困难是:海洋声信道的长延时、可用频带有限、严重的时变多途影响、功耗限制、网络安全性等.在分析水下无线通信的特殊环境后,针对水声通信网的多址接入技术进行了研究,选择适合的传输方式及相关协议构建基于OFDM与CDMA技术结合的水下通信网多载波CDMA系统;在matlab上实现多载波CDMA技术的水声通信网络节点对节点的数据传送,并得出了该系统的仿真结果:在帧长一定的情况下,随着信噪比的增大,系统的误码率会减小.在信噪比一定的情况下,子载波数目的进一步增大不会带来系统误码率的改善反而会使系统复杂性增加,降低系统的平均吞吐量,因此子载波数的选择应该在系统复杂性和效率之间折衷考虑.当水声信道上的信噪比一定时,可以通过控制数据帧的长度和子载波的个数来实现较高的网络平均吞吐量.     

X波段导航雷达浪高实时测量研究

针对舰船对浪高实时测量的需要,提出了基于X波段导航雷达浪高实时测量的方案。介绍X波段导航雷达浪高测量原理,建立基于X波段导航雷达浪高实时测量的数学模型。通过某海域实测采集的雷达图像,经过数学模型反演得出浪高实时数据,并与采用浮标传感器实时测量的浪高数据进行对比,发现X波段导航雷达与浮标传感器测得的浪高数据有近一致的线性关系,标准差也较小。从一定程度上为舰船浪高测量提供一种可行性方法。     

重力式海洋平台的运动响应

本文在分析重力式海洋平台的力学模型基础上，建立了平台运动的拉格朗日方程，并用多尺度法求解平台的运动响应。