井外爆炸点源激发井孔声波场

利用井外爆炸点源激发的声波场与井孔的相互作用模拟井间地震的物理过程,推导了全频城井孔内外声波场的理论计算公式,并针对不同震源主频、不同源距(震源到井轴的径向距离)和软硬地层进行了井内声场的全波模拟与频率-相速度分析.结果表明:井外爆炸点源激发井孔内外的声场等效于无穷多级声场迭加的结果;震源靠近井壁时的频率-相速度图与震源在井内时相似;震源的主频越高、源距和接收器离井轴的径向距离越大、地层越硬,则顾及的多级声场的项数就要越多;震源主频越低、源距越小,井中激发的斯通利波则越强.     

加强学籍管理制度建设保障研究生培养质量

近几年来，我国的研究生教育蓬勃发展，招生规模逐年增加，人才培养模式呈现多样化趋势。保证培养质量已成为当前研究生教育管理工作的重要任务。以《普通高等学校学生管理规定》为政策依托，建立健全各项规章制度，做到制度规范化、标准化，是我们做好研究生教育管理工作的基础；严格过程管理对于提高研究生培养质量能够起到积极的保证作用；坚持中期考核，建立淘汰制。进一步完善研究生信息管理网络系统等这些过程管理的措施都能促进研究生教育的良性发展。     

硅钢中合金元素的几种仪器分析方法

概述了硅钢中常见合金元素的种类,介绍了电感耦合等离子体原子发射光谱、电感耦合等离子体质谱、辉光放电发射光谱和X-射线荧光光谱几种仪器测定硅钢中合金元素的方法及分析原理,通过应用实例分析,总结了各种仪器分析方法的优缺点,并对硅钢中合金元素的仪器分析方法的手段与方向进行了展望。     

弹性耦合激励振动筛有限元结构模态分析

利用SAP5P程序计算了弹性耦合激励振动筛前10阶固有特性，计算结果表明：从降噪观点看，前10阶模态应采取抑制措施；从提高寿命观点看，应注意第2阶和第4～10阶模态．同时提出了为降噪增寿而采取的较为合理的结构修改措施．计算结果与理论分析相吻合．     

赤泥矿中的稀土元素测定方法的研究

对目前较常用的稀土元素的测定方法进行了综述,分别探讨了各方法的优缺点.并着重研究了采用ICP-AES（电感耦合等离子体发射光谱仪）来测定赤泥矿中的15种稀土元素的方法,进行了一系列实验,结果表明,该方法用来检测稀土元素可行有效、方便快捷、精密度高.     

Acoustic Measurements of the Anisotropy of Dynamic Elastic and Poromechanics Moduli under Three Stress/Strain Pathways

A series of triaxial compression experiments have been conducted to investigate the effects of induced stress on the anisotropy developed in dynamic elastic and poroelastic parameters in rocks. The measurements were accomplished by utilizing an array of piezoelectric compressional and shear wave sensors mounted around a cylindrical sample of porous Berea sandstone. Three different types of applied states of stress were investigated using hydrostatic, triaxial, and uniaxial strain experiments. During the hydrostatic experiment, where an isotropic state of stress was applied to an isotropic porous rock, the vertical and horizontal acoustic velocities and dynamic elastic moduli increased as pressure was applied and no evidence of stress induced anisotropy was visible. The poroelastic moduli (Biot’s effective stress parameter, α) decreased during the test but also with no evidence of anisotropy. The triaxial compression test involved an axisymmetric application of stress with an axial stress greater than the two constant equal lateral stresses. During this test a marked anisotropy developed in the acoustic velocities, and in the dynamic elastic and poroelastic moduli. As axial stress increased the magnitude of the anisotropy increased as well. The uniaxial strain test involved axisymmetric application of stresses with increasing axial and lateral stresses but while maintaining a zero lateral strain condition. The uniaxial strain test exhibited a quite different behavior from either the triaxial or hydrostatic tests. As both the axial and lateral stresses were increased, an anisotropy developed early in the loading phase but then was effectively “locked in” with little or no change in the magnitude of the values of the acoustic velocities, or the dynamic elastic and poroelastic parameters as stresses were increased. These experimental results show that the application of triaxial states of stress induced significant anisotropy in the elastic and poroelastic parameters in porous rock, while under the uniaxial strain condition the poromechanics, Biot’s effective stress parameter, exhibited the largest variation among the three test conditions.     

建筑物可靠性鉴定方法的发展概况

阐述了建筑物可靠性鉴定几种方法，并提出了数字信号处理技术在建筑物可靠性鉴定中应用的可行性。     

微波消解-电感耦合等离子体发射光谱法测定铁矿石中次、痕量元素

采用先进的微波消解技术进行样品的前处理,建立了用电感耦合等离子发射光谱仪同时测定铁矿石中十余种元素的分析方法.通过对实际样品的分析试验,测定的灵敏度、准确度、精密度和回收率均取得了满意的结果.     

Potential of Acoustic Methods in Monitoring the Structure and Physicomechanical Properties of Porous Materials

The task of monitoring porous materials is formulated. Principles for developing and using nondestructive acoustic methods for monitoring the structure and physicomechanical properties of porous materials are suggested and discussed. It is noted that the solution of each monitoring problem for porous materials requires an individual, often nontraditional, approach and its success is determined by the possibility of developing theoretical or experimental correlation dependences between the acoustic and material properties sought. It is shown that it is possible from the results of measuring propagation velocity and elastic wave damping factors to determine parameters such as elasticity, inelasticity, porosity, defectiveness, the size of structural elements, anisotropy, and property inhomogeneity.     

Vibration Testing at Meazza Stadium: Reliability of Operational Modal Analysis to Health Monitoring Purposes

In the last years an increasing interest has been devoted to all the topics related to the security and safety of people. Particular attention has been paid to health monitoring of large civil structures hosting many people, such as high-rise buildings and stadiums. Some extraordinary events, such as the Millennium Bridge oscillations in London, excited by pedestrians, or the Bruce Springsteen concert at the Ullevi Stadium in which coordinated jumps from the crowd caused serious damage to the structure, and drew attention toward a deeper and more careful study of all those problems related to the dynamic behavior of civil structures and their interaction with crowds. Research on these topics is also aimed, among others, at developing techniques allowing for a continuous monitoring of the structure, starting from a set of measurements that can be performed continuously, 24?h a day, without the need to stop the structure's functionality. The vast scientific literature confirms the possibility of relating structural health to the evolution of modal parameters, often reaching the aim of localizing any eventual damage, a task otherwise impossible with different techniques. This paper shows part of a long lasting project involving Politecnico di Milano in the setting up of a permanent health monitoring system at the G. Meazza Stadium in Milan. The aim of this project was the evaluation of the actual health state of the structures constituting the stands of the stadium and the deployment of a permanent monitoring system to record the vibration levels reached in all substructures during each event. Evaluation of the actual structure condition was performed by the use of ambient vibration, which was also checked against traditional experimental modal analysis, performed by using an inertial force given by a hydraulic actuator and a detailed measurement mesh. This offered the chance to exploit all possible information concerning natural frequencies, modal shapes, and damping factors. This task is extremely time consuming and expensive, therefore, it cannot be repeated very often. The possibility of using the data coming from the permanent monitoring system, which is about to be installed, is then an attractive perspective to improve structural diagnosis. It is expected that using operational modal analysis techniques will mean knowledge of the excitation applied to the structure will not be required. The parameter estimation obtained by this technique is usually affected by a spread, given both by the uncertainty of the adopted identification techniques and the influence of external parameters, such as crowd loading or temperature. As damage identification is related to changes of the modal parameters, the evaluation of their normal spread is fundamental to fix a threshold in order to identify possible worrysome situations. This paper deals with the identification of the spread in the modal parameter estimation of one of the grandstands of the so-called 3° ring of the G. Meazza Stadium in Milan, performed analyzing data collected over more than one year. Vibration data have been recorded during different events, such as soccer matches and concerts. The considered data came from a set of sensors similar to that which is to be installed for the permanent monitoring system, to check about the possibility to use the monitoring system as a diagnostic tool for the structure. A study was also carried out to identify critical aspects in the sensors’ choice and their placement, in order to provide useful information about the design of the permanent monitoring system. The presented results can be used to determine confidence intervals out of which changes in the modal properties can be considered anomalous, and so, worthy of being deeply investigated to assess structural integrity.     

Progress of Separation and Determination Methods for Rare Earth Elements

~~Progress of Separation and Determination Methods for Rare Earth Elements     

Ensuring the future of professional psychology.

The future of professional psychology will be ensured if the profession collectively addresses several key issues critical to its success. This address focuses on ways to guarantee patients' rights, expand our visions for professional psychology, remain a doctoral profession, and make science an ally of practice. It urges us to use the resources of APA and our state and provincial psychological associations to accomplish the goal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

利用道口预警设备保证行车安全

提出一种在无人看守道口设置自动报警装置的方案．利用6502电气集中电路条件，实现道口自动预警为企业的安全保产提供保障．     

企业科技档案管理和利用的要素与方法

文章在回顾企业科技档案的含义与类型的基础上,论述了企业科技档案管理健全机构、提高人员素质、完善制度、强化考核、严格归档质量以及科学有效收集档案等管理要素,提出了利用信息反馈和跟踪调查的方法来最大限度地发挥科技档案的价值。