基于多元整体最小二乘优化的多点灰色动态变形分析模型

提出一种多元整体最小二乘优化的多点灰色动态模型,并结合实例验证优化的MGM(1,n)模型的优越性。将优化的MGM(1,n)模型与一般的MGM(1,n)模型进行对比,分析两种模型的建模值和预测值。结果表明,优化的MGM(1,n)模型在建模数据多于4期的情况下建模精度更高,预测精度更准确,更符合实际情况。     

大气重力信号的理论计算及其检测

基于标准大气定律和大气圆柱体分布模型,本文引进了大气重力格林函数,用离散格积方法求得了大气对重力场观测的影响,对台站高程、周围地形和地表温度变化等因素的影响问题进行了讨论．结果说明台站近区气压变化是大气重力信号的主要贡献者,考虑大气质量负荷引起的弹性地球形变效应后,对距台站0．5°的区域积分获得的大气重力导纳值为-0．3603μGal／hPa,占全球大气变化引起的总信号的90％以上,这一理论模型结果与超导重力仪实测结果相吻合,并能较有效地用于消除重力观测中的气压干扰成分．     

Optimum design and application of non‐traditional tuned mass damper toward seismic response control with experimental test verification

A variant type of tuned mass damper (TMD) termed as ‘non‐traditional TMD (NTTMD)’ is recently proposed. Mainly focusing on the employment of TMD for seismic response control, especially for base‐isolated or high‐rise structures, this paper aims to derive design formulae of NTTMDs based on two methodologies with different targets. One is the fixed points theory with the performance index set as the maximum magnitude of the frequency response function of the relative displacement of the primary structure with respect to the ground acceleration, and the other is the stability maximization criterion (SMC) to make the free vibration of the primary structure decay in the minimum duration. Such optimally designed NTTMDs are compared with traditional TMDs by conducting both numerical simulations and experiments. The optimum‐designed NTTMDs are demonstrated to be more effective than the optimum‐designed traditional TMDs, with smaller stroke length required. In particular, the effectiveness of the TMDs combined with a base‐isolated structure is investigated by small‐scale model experimental tests subjected to a time scaled long period impulsive excitation, and it is demonstrated that the SMC‐based NTTMD can suppress structural free vibration responses in the minimum duration and requires much smaller accommodation space. Additionally, a small‐scale shaking table experiment on a high‐rise bending model attached with a SMC‐based NTTMD is conducted. This study indicates that NTTMD has a high potential to apply to seismic response control or retrofit of structures such as base‐isolated or central column‐integrated high‐rise structures even if only a limited space is available for accommodating TMDs. Copyright © 2015 John Wiley & Sons, Ltd.     

确定先期固结压力的数学模型法

地基土的先期固结压力是判断土体应力历史的一个指标。在不同应力历史状况的土体变形分析中它也是一个重要的计算参数。因此,方便、准确地确定先期固结压力就显得尤为重要。依据理论研究和试验分析,提出了一种新的确定方法：数学模型法。润扬大桥土样试验的结果证明了此法的可行性。     

邻近算法在微地震震源位置和一维速度模型同时反演中的应用

微地震事件的空间分布可以用来监测水力压裂过程中裂缝的发育情况.因此,震源定位是微震监测中重要的环节.震源定位依赖准确的速度模型,而震源位置和速度模型的耦合易导致线性迭代的同时反演方法陷入局部极小值.邻近算法作为一种非线性全局优化算法,能够最大程度地避免陷入局部最优解.本文将邻近算法应用于单井监测的微震定位和一维速度模型...     

Comparison of cell- and vertex-centered discretization methods for flow in a two-dimensional discrete-fracture–matrix system

Simulations of flow for a discrete-fracture model in fractured porous rocks have gradually become more practical, as a consequence of increased computer power and improved simulation and characterization techniques. Discrete-fracture models can be formulated in a lower-dimensional framework, where the fractures are modeled in a lower dimension than the matrix, or in an equi-dimensional form, where the fractures and the matrix have the same dimension.     

2015年5月大气环流和天气分析

对2015年3—5月T639、ECMWF（文中简称EC）及日本数值模式中期预报产品进行了检验和对比。结果表明：三个模式对亚洲中高纬地区大尺度环流和850 hPa温度的演变和调整均具有较好的预报性能,EC模式对西风指数、850 hPa温度转折过程和变化幅度的预报略优于其他两个模式。对2015年3月31日至4月1日北方地区强沙尘暴天气过程的主要影响天气系统,三个模式预报能力相当,121 h时效都较好地预报出了地面冷高压,但强度和范围与实况有一定偏差。     

Geobiological interpretation of the oxygen-deficient deposits of the Middle Permian marine source rocks in South China:A working hypothesis

To decipher the origin of oxygen-deficient shelfal deposits is significant for tracing the distribution of marine source rocks and interpreting the evolution of depositional environment. The origin of the Middle Permian Chihsia Formation in South China remains a puzzle for long with its evident oxygen-deficient features but diverse benthos. This paper shows a typical Chihsian depositional rhythm composed of the massive and the laminated limestones with ecological and geochemical features. Massive bioclastic limestone from the rhythm was aerobic in paleoxygenation condition indicated by both the ecological and geochemical features. However, a contradictory oxygenation was inferred for the “laminated” counterpart from the rhythm, with the ecological signal being aerobic and the geochemical one being anoxic. The difference in ecological and geochemical indications was interpreted as the instability of paleoxygenation condition in shelf environments, caused by an enhanced paleoproductivity. Rhythmic occurrence of the oxygen-deficient condition might have been stemmed from paleo-Tethyan paleocurrents flowing across South China. __________ Translated from Earth Science—Journal of China University of Geosciences, 2007, 32(6): 789–796 [译自: 地球科学—中国地质大学学报]     

Blazar天体中光学射电大爆发的频谱演化

本文讨论Ｂｌａｚａｒ天体中光学射电大爆发频谱演化的理论模型．考虑沿喷流传播的相对论性激波所注入或加速的相对论性电子，受到康普顿、同步辐射和绝热膨胀三种损耗，并计及相对论电子能谱的高能截断．假定喷流轴线与观测者方向构成很小角度．文中给出了大爆发频谱三阶段连续演化的特性，即康普顿阶段，同步辐射阶段和绝热膨胀阶段的爆发特性．频谱演化用（Ｓｍ－ｖｍ）关系表达（见图２，图中Ｓｍ为频谱反转流量，ｖｍ为反转频率），它与一些Ｂｌａｚａｒ天体中观测到的典型形式相符合．     

Parameter and rating curve uncertainty propagation analysis of the SWAT model for two small Mediterranean catchments

Abstract

The SWAT model was tested to simulate the streamflow of two small Mediterranean catchments (the Vène and the Pallas) in southern France. Model calibration and prediction uncertainty were assessed simultaneously by using three different techniques (SUFI-2, GLUE and ParaSol). Initially, a sensitivity analysis was conducted using the LH-OAT method. Subsequent sensitive parameter calibration and SWAT prediction uncertainty were analysed by considering, firstly, deterministic discharge data (assuming no uncertainty in discharge data) and secondly, uncertainty in discharge data through the development of a methodology that accounts explicitly for error in the rating curve (the stage?discharge relationship). To efficiently compare the different uncertainty methods and the effect of the uncertainty of the rating curve on model prediction uncertainty, common criteria were set for the likelihood function, the threshold value and the number of simulations. The results show that model prediction uncertainty is not only case-study specific, but also depends on the selected uncertainty analysis technique. It was also found that the 95% model prediction uncertainty interval is wider and more successful at encompassing the observations when uncertainty in the discharge data is considered explicitly. The latter source of uncertainty adds additional uncertainty to the total model prediction uncertainty.

Editor D. Koutsoyiannis; Associate editor D. Gerten

Citation Sellami, H., La Jeunesse, I., Benabdallah, S., and Vanclooster, M., 2013. Parameter and rating curve uncertainty propagation analysis of the SWAT model for two small Mediterranean watersheds. Hydrological Sciences Journal, 58 (8), 1635?1657.