吉林二道甸金矿成矿控制条件分析及靶区评价

二道甸子金矿具有独特的成因机制及成矿控制条件。通过对该矿主矿带金矿化作用与古生代含碳变质岩系、弧形构造带以及与海西期黑云母花岗岩侵入作用之间的关系分析，指出后者是金矿成矿的主要控制条件；并据此总结出金矿富集规律和矿体预测准则，指出在矿区外国及深部存在进一步工作的找矿靶区。     

Predictive control of seismic structures with semi‐active friction dampers

In this paper a predictive control method especially suitable for the control of semi‐active friction dampers is proposed. By keeping the adjustable slip force of a semi‐active friction damper slightly lower than the critical friction force, the method allows the damper to remain in its slip state throughout an earthquake of arbitrary intensity, so the energy dissipation capacity of the damper can be improved. The proposed method is formulated in a discrete‐time domain and cast in the form of direct output feedback for easy control implementation. The control algorithm is able to produce a continuous and smooth slip force for a friction damper and thus avoid exerting the high‐frequency structural response that usually exists in structures with conventional friction dampers. Using a numerical study, the control performance of a multiple degrees of freedom (DOF) structural system equipped with passive friction dampers and semi‐active dampers controlled by the proposed method are compared. The numerical case shows that by merely using a single semi‐active friction damper and a few sensors, the proposed method is able to achieve better acceleration reduction than the case using multiple passive dampers. Copyright © 2004 John Wiley & Sons, Ltd.     

Development of rational models for tunnel blast prediction based on a parametric study

The empirical models available for prediction of the tunnel blast results like pull ratio, specific charge, specific drilling and overbreak have some inherent shortcoming in absence of any parametric study at the backdrop. Hence, the models use different constituting parameters and provide values which differ widely. After a thorough review of literature and field investigations in the drivages of mines and tunnels some parameters were identified. Those parameters were subjected to Multiple Linear Regression analyses to filter out the most influencing ones which represent the rockmass properties, the tunnel configurations and the blast designs. A parameter called Tunnel Blasting Index (TBI) was conceptualized and was expressed in terms of those most influencing parameters. All the blast results observed during the filed investigations could be well related to a single index TBI. Some adjustments on account of shape of the tunnel and joint orientations, which were not addressed in the available models, are suggested in the developed models.     

影响上海市及邻近区域台风的灰色预测

本文利用台风年鉴１９８１￣１９９６年的资料,根据灰色灾变预测方法,建立了对上海市及其邻近区域产生严重影响的强台风出现时间的ＧＭ（１,１）预测模型,经过检验,精度达到优级,据此预测,下次人侵袭本地区的强台风出现时间为２００１年,同时,用灰色拓扑方法对未来几年上海市江苏、浙江沿海区域产生８级以上大风天气的台风个 数进行了逐年预测。     

地震震级预测的相关向量机模型

为了借助容易获取的地震相关因素间接预测地震震级,提出基于相关向量机（Relevance Vector Machine,RVM）方法的地震震级预测模型。通过样本学习建立地震震级与地震累积频度、累积释放能量、平均震级、b值、η值和相关区震级等6个主要影响因素之间的非线性映射关系,利用已知影响因素预测地震震级。结果表明:RVM模型预测结果均优于BP神经网络及SOM-BP神经网络预测结果;通过敏感因子分析比较各因素的敏感程度,b值和η值最为突出,在震级研究中应重点分析。综合分析,RVM模型具有精度高和离散性小等优点,对地震震级预测有较好的推广价值。     

Predictive stability indicator: a novel approach to configuring a real‐time hybrid simulation

Real‐time hybrid simulation (RTHS) is an effective and versatile tool for the examination of complex structural systems with rate dependent behaviors. To meet the objectives of such a test, appropriate consideration must be given to the partitioning of the system into physical and computational portions (i.e., the configuration of the RTHS). Predictive stability and performance indicators (PSI and PPI) were initially established for use with only single degree‐of‐freedom systems. These indicators allow researchers to plan a RTHS, to quantitatively examine the impact of partitioning choices on stability and performance, and to assess the sensitivity of an RTHS configuration to de‐synchronization at the interface. In this study, PSI is extended to any linear multi‐degree‐of‐freedom (MDOF) system. The PSI is obtained analytically and it is independent of the transfer system and controller dynamics, providing a relatively easy and extremely useful method to examine many partitioning choices. A novel matrix method is adopted to convert a delay differential equation to a generalized eigenvalue problem using a set of vectorization mappings, and then to analytically solve the delay differential equations in a computationally efficient way. Through two illustrative examples, the PSI is demonstrated and validated. Validation of the MDOF PSI also includes comparisons to a MDOF dynamic model that includes realistic models of the hydraulic actuators and the control‐structure interaction effects. Results demonstrate that the proposed PSI can be used as an effective design tool for conducting successful RTHS. Copyright © 2016 John Wiley & Sons, Ltd     

泥沙输移方程在地貌预测模型研究应用中的局限性

Sources of uncertainty or error that arise in attempting to scale up the results of laboratory-scale sediment transport studies for predictive modeling of geomorphic systems include: (i) model imperfection, (ii) omission of important processes, (iii) lack of knowledge of initial conditions, (iv) sensitivity to initial conditions, (v) unresolved heterogeneity, (vi) occurrence of external forcing, and (vii) inapplicability of the factor of safety concept. Sources of uncertainty that are unimportant or that can be controlled at small scales and over short time scales become important in large-scale applications and over long time scales. Control and repeatability, hallmarks of laboratory-scale experiments, are usually lacking at the large scales characteristic of geomorphology. Heterogeneity is an important concomitant of size, and tends to make large systems unique. Uniqueness implies that prediction cannot be based upon first-principles quantitative modeling alone, but must be a function of system history as well. Periodic data collection, feedback, and model updating are essential where site-specific prediction is required.     

Time variant analysis of geomagnetic signals describes the volcanic activity of Mt. Etna between early 2000 and late 2002

Volcanomagnetic anomalies have been mostly observed during strong eruptions. Our aim is to improve the geomagnetic data analysis to evidence the anomalies occurring in a larger time span, especially in the phases preceding the eruptive events. We developed a time variant statistical approach and applied it to the 2000–2002 Etna geomagnetic temporal series. It is based on an algorithm that statistically predicts the geomagnetic field at the station on the volcanic edifice by that recorded at the remote one. In such a way a number of significant changes in the time series (called statistical innovations), marking the local magnetic field change, were detected. The distribution of such statistical innovations accurately describes the Etna volcanic evolution: we note a progressive increase of the innovation occurrence as the eruptive cycles were approaching and only few and weak innovations at times between the various eruptive cycles. The significance of this analysis is further confirmed by the close agreement among the mean square prediction error, strain release and the volcanic activity behavior. On the contrary, the geomagnetic field at a single station or its difference at two stations do not have any clear correlation with other measured physical quantities. The complex pattern of the prediction error was also investigated by a multifractal analysis. We found that the Holder regularity increases with the intensification of the volcanic activity, implying that innovations tend to be less sporadic and correlated during the major volcanic phases.     

Semi‐active multi‐step predictive control of structures using MR dampers

A semi‐active multi‐step predictive control (SAMPC) system with magnetorheological (MR) dampers is developed to reduce the seismic responses of structures. This system can predict the next multi‐step responses of structure according to the current state and has a function of self‐compensation for time delay that occurred in real application. To study the performance of the proposed control algorithm for addressing time delay and reducing the seismic responses, a numerical example of an 11‐story structure with MR dampers is presented. Comparison with the uncontrolled structure indicates that both the peak and the norm values of structural responses are all clearly reduced when the predictive length l?10 and the delayed time step d?20 are selected, and the SAMPC strategy can guarantee the stability of the controlled structure and reduce the effects of time delay on controlled responses to a certain extent. A performance comparison is also made between the SAMPC strategy and the passive‐off and passive‐on methods; results indicate that this SAMPC system is more effective than the two passive methods in reducing structural responses subjected to earthquakes. Copyright © 2008 John Wiley & Sons, Ltd.     

绕射波信息提取与成像技术研究——以某盆地海相碳酸盐岩为例

绕射波是提高地震分辨率或超分辨率的重要信息载体,绕射波的提取与成像技术是地震勘探提取小尺度异常体的有效途径.基于传统的反射成像的处理过程没有充分地利用到绕射信息,特别是一些常规处理方法通常对绕射信息有着压制作用.为了进一步提高地震资料中绕射波的使用效率,重点研究了在成像道集上采用预测反演算法对绕射波进行提取与成像,并以...