宝鼎矿区深部水文地质条件研究及涌水量计算

宝鼎矿区浅部资源行将枯竭,深部开采已迫在眉睫,而预测深部涌水量成为其首要解决的问题。通过对矿区深部水文地质条件研究与矿井充水因素的分析,认为矿区各含水间水力联系差,同一含水层组的不同地段间的含水裂隙的连通性亦差;断层多为高角度压性逆断层,导水性差,富水性弱;矿区上部水平及下部水平的浅埋区的充水水源主要为大气降水和老窑水,而下部水平主要的充水水源为上覆水平的采空区积水和地下水。运用比拟法和地下水动力学对延深的第一接替水平四个区段的较大涌水量和一般涌水量进行了计算,经过比较,采用了比拟法的计算结果:矿井的一般涌水量为2860.88m3/d,据此提出了切实可行防治水措施,从而为矿井深部建设提供了水文地质依据。

国外水质色度测定标准方法

1 日本 1971年北海道分析化学协会出版的《水的分析》一书,包括了日本《工业标准用水排水试验方法》和美国《水和废水标准试验方法》。1975年中译本对水质色度规定了目测铂钴标准法,也介绍了分光光度计法,测量波长为370～400nm,绘出了用5cm比色杯,在370nm波长处的标准曲线,斜率较大,测定范围可达100度,要求用离心法除去浊度后再测定色度。

Inverse displacement analysis of the general six degree-of-freedom serial robot based on optimization method

The paper presents a new solution of inverse displacement analysis of the general six degree-of-freedom serial robot.The inverse displacement analysis of the general serial robot is transformed into a minimization problem and then the optimization method is adopted to solve the nonlinear least squares problem with the analytic form of new Jacobian matrix.In this way,joint variables of the general serial robot can be searched out quickly under the desired precision when positions of the three non-collinear end effector points are given.Compared with the general Newton iterative method,the proposed algorithm can search out the solution when the robot is at the singular configuration and the initial configuration used in the optimization method may also be the singular configuration.So the convergence domain is bigger than that of the general Newton iterative method.Another advantage of the proposed algorithm is that positions of the three non-collinear end effector points are usually much easier to be measured than the orientation of the end effector.The inverse displacement analysis of the general 6R(six-revolute-joint) serial robot is illustrated as an example and the simulation results verify the efficiency of the proposed algorithm.Because the three non-collinear points can be selected at random,the method can be applied to any other types of serial robots.

Numerical Simulation for Accuracy of Velocity Analysis in Small-Scale High-Resolution Marine Multichannel Seismic Technology

When used with large energy sparkers, marine multichannel small-scale high-resolution seismic detection technology has a high resolution, high-detection precision, a wide applicable range, and is very flexible. Positive results have been achieved in submarine geological research, particularly in the investigation of marine gas hydrates. However, the amount of traveltime difference information is reduced for the velocity analysis under conditions of a shorter spread length, thus leading to poorer focusing of the velocity spectrum energy group and a lower accuracy of the velocity analysis. It is thus currently debatable whether the velocity analysis accuracy of short-arrangement multichannel seismic detection technology is able to meet the requirements of practical application in natural gas hydrate exploration. Therefore, in this study the bottom boundary of gas hydrates(Bottom Simulating Reflector, BSR) is used to conduct numerical simulation to discuss the accuracy of the velocity analysis related to such technology. Results show that a higher dominant frequency and smaller sampling interval are not only able to improve the seismic resolution, but they also compensate for the defects of the short-arrangement, thereby improving the accuracy of the velocity analysis. In conclusion, the accuracy of the velocity analysis in this small-scale, high-resolution, multi-channel seismic detection technology meets the requirements of natural gas hydrate exploration.

Forward displacement analysis of a redundant parallel manipulator by approximation algorithms

This paper presents the forward displacement analysis of an 8-PSS(prismatic-spherical-spherical)redundant parallel manipulator whose moving platform is linked to the base platform by eight kinemtic chains consisting of a PSS joint and a strut with fixed length.A general approximation algorithm is used to solve the problem.To avoid the extraction of root in the approximation process,the forward displacement analysis of the 8-PSS redundant parallel manipulator is transformed into another equivalent problem on the assumption that the strut is extensible while the slider is fixed.The problem is solved by a modified approximation algorithm which predicates that the manipulator will move along a pose vector to reduce the difference between the desired configuration and an instantaneous one,and the best movement should be with minimum norm and least quadratic sum.The characteristic of this modified algorithm is that its convergence domain is larger than that of the general approximation algorithm.Simulation results show that the modelified algorithm is general and can be used for the forward displacement analysis of the redundant parallel manipulator actuated by a revolute joint.

我们怎样在红专学校中教化学课

国光制药厂、水利模型厂、第三铅丝网厂、三厂联合举办的红专学校，是1958年10月14日正式成立的。我们组担任了这个学校的高、初中化学课，在这两个多月的办学过程中，我们学到两点：一、教学内容必须与生产相结合；二、教学方法要根据学员的特点。

Applications of different criteria in structural damage identification based on natural frequency and static displacement

This paper presents a damage identification method that consists of a fusion sensitivity matrix that contains information on dynamic and static responses. Based on natural frequency and static displacement, the study defines and considers damage criteria such as 1D and 2D single and fusion load cases. To overcome the lack of sufficient information on damage identification in large-scale structures, the authors consider multiple responses to and objective descriptions of uncertainties and various criteria.According to the finite element model and the structural responses described and measured, the fusion methods and damage criteria treat uncertainty as non-probability intervals. As long as we know the bounds of uncertain parameters, the intervals of the elemental stiffness parameters in undamaged and damaged models can be obtained by interval technology. Two numerical examples—a damage-criteria numerical example and a 5-span with 25-bar truss structure in a space solar power station—are proposed. Both examples indicate the veracity of the interval method.

Excavation-induced microseismicity: microseismic monitoring and numerical simulation

The volume of influence of excavation at the right bank slope of Dagangshan Hydropower Station, southwest China, is essentially determined from microseismic monitoring, numerical modeling and conventional measurements as well as in situ observations. Microseismic monitoring is a new application technique for investigating microcrackings in rock slopes. A micro- seismic monitoring network has been systematically used to monitor rock masses unloading relaxation due to continuous exca- vation of rock slope and stress redistribution caused by dam impoundment later on, and to identify and delineate the potential slippage regions since May, 2010. An important database of seismic source locations is available. The analysis of microseismic events showed a particular tempo-spatial distribution. Seismic events predominantly occurred around the upstream slope of 1180 m elevation, especially focusing on the hanging wall of fault XL316-1. Such phenomenon was interpreted by numerical modeling using RFPA-SRM code （realistic failure process analysis-strength reduction method）. By comparing microseismic activity and results of numerical simulation with in site observation and conventional measurements results, a strong correlation can he obtained between seismic source locations and excavation-induced stress distribution in the working areas. The volume of influence of the rock slope is thus determined. Engineering practices show microseismic monitoring can accurately diagnose magnitude, intensity and associated tempo-spatial characteristics of tectonic activities such as faults and unloading zones. The integrated technique combining seismic monitoring with numerical modeling, as well as in site observation and conventional surveying, leads to a better understanding of the internal effect and relationship between microseismic activity and stress field in the right bank slope from different perspectives.