基于神经网络的图像来源识别方法比较研究

随着手机等便携式智能电子设备的普及,图像已成为最重要的信息载体之一,在新闻、社交及司法等领域发挥着重要作用.在享用电子图像带来便捷性的同时,图像处理工具给不法分子通过篡改电子图像实施诈骗等犯罪活动提供了可能,识别图像来源、辨别图像真伪已成为遏制和惩罚此类犯罪活动的重要技术手段.该文讨论了神经网络在图像源识别中的应用方法...     

模数式桥梁伸缩装置疲劳试样尺度研究

为了研究模数式桥梁伸缩装置采用单跨试样代替三跨试样进行疲劳试验的可行性,首先采用力学简化模型对伸缩装置主要构件两种受力情况进行分析,再利用Ansys分析软件分别建立了整体加强320伸缩装置单跨试样与三跨试样的有限元模型,对伸缩装置进行强度对比分析.结果表明:在同种加载情况下,单跨模型中梁最大应力较多跨模型大,而多跨模型...     

高校学生主体性养成研究

主体性是个体在认识改造对象世界过程中呈现出的主观自觉、自主独立并富于创造的行为表现。教师通过转变育人思路,实现师生主体性同塑;通过丰富育人实践,将高校主体性教育与外在世界紧密融合,推进高校思政育人工作取得新进展。     

高海拔地区500kV变电站设备相间操作冲击放电特性

相间操作冲击放电特性是决定变电站设计尺寸的一个重要方面。为获得我国高海拔地区500kV变电站的设计依据,结合云南电网公司500kV建塘输变电工程,分别在3个不同海拔高度地区武汉(23m)、西宁(2 254m)、大武(3 742m),开展了模拟真型500kV变电站典型电极—软母线和均压环的相间操作冲击试验研究。利用升降法获得5～8m间隙距离内的相间操作冲击放电特性曲线,分析电压分配系数对相间间隙空气绝缘的影响,并按不同的海拔校正方法对试验结果进行校正分析和比较。试验表明:受海拔高度的影响,高海拔变电站设备相间操作冲击平均击穿场强较低海拔有明显的下降,相间操作冲击放电电压U50随着电压分配系数增大而增大。通过对比国内外不同海拔校正方法,建议高海拔地区500kV变电站均压环相间操作冲击海拔校正采用IEC 60071-2—1996标准的方法进行海拔校正;软母线相间操作冲击海拔校正采用带m因子的修正方法进行海拔校正。     

Breakability analysis of the elastic rock beam based on the winkler model

Based on the Winkler model, a mechanic model was established with formulas derived concerned with the deformations before and after a roof breakage at places in front of and at the back of the working face. In accordance with the theory for rock beam breakage, the beam breaking position in front of the working face is specified. In addition, the formulas were developed for the velocity of the subsidence at observatory point A in front of the working face when the coal wall serves as the coordinate center and the advance distance at time t as the dynamic coordinate. In the application of the above-mentioned achievements to the practice of Xieqiao Mine and the mines of the Eastern Panji Company of Huainan Mining（Group） Co. Ltd., the results concerned with the velocity with which the roof stratum tends to subside before and after breakage as derived from the mechanic model are well compatible to the results based on in-situ observations and measurements.     

软件延迟符合法分辨氡同位素的仿真研究

本工作以MATLAB软件仿真的方式,探索用软件方法实现延迟符合法分辨氡同位素;并改变延迟时间和开门时间寻找较好的分辨效果。结果显示,该方法可降低测量成本,延迟时间调整方便,并可用于低水平活度氡同位素测量。     

化学法处理混合电镀废水及药剂选择

通过热动力学分析、理论计算和实验,确定在碱性条件下用NaClO作氧化剂,Na₂S和FeSO₄作还原剂处理混合电镀废水的工艺流程,并通过计算和实验确定了Na₂S与FeSO₄的最佳药剂比:Na₂S为80%~90%,FeSO₄为10%~20%.Na₂S+FeSO₄比单独使用FeSO₄少产生60%~70%的污泥.该工艺在实际工程运行过程中效果良好.     

A new method for mining deformation monitoring with GPS-RTK

Based on ranging intersection theory, a new method which is simple and easy to operate was proposed for data collection in the mine surface deformation monitoring with GPS-RTK centering rod measurements. It can fully eliminate the inevitable shaking error and the vertical deflection, and to some extent weaken the multipath effect on the estimates of coordinates in a relatively short period of time, using high-frequency observations. The results show that three-dimensional coordinates with a height accuracy better than 1 cm, horizontal accuracy better than 2-4 cm can be achieved through only 15-30 s continuous observation by 20 Hz high-frequency and effectively improve the measurement accuracy and efficiency of RTK, fully satisfying the high-speed and high-precision data acquisition in mine surface subsidence deformation monitoring.     

Aeroservoelastic model based active control for large civil aircraft

A modeling and control approach for an advanced configured large civil aircraft with aeroservoelasticity via the LQG method and control allocation is presented.Mathematical models and implementation issues for the multi-input/multi-output(MIMO) aeroservoelastic system simulation developed for a flexible wing with multi control surfaces are described.A fuzzy logic based optimization approach is employed to solve the constrained control allocation problem via intelligently adjusting the components of output v...     

Study on the hydrothermal drying technology of sewage sludge

Drying of sewage sludge is an effective way for treatment and utilization of sewage sludge,where reduction of energy consumption is one of the major technical challenges.So we experimentally investigated the possibility of the hydrothermal treatment.We have found that treatment of sewage sludge by saturated steam with the temperature of 190°C and pressure of 20 bar can dramatically improve the dehydration performance of the slurry like product.And the water content can be reduced down to about 55% by a mech...