Charge coupled device based on optical tomography system in detecting air bubbles in crystal clear water

Optical tomography is one of the tomography methods which are non-invasive and non-intrusive system, consisting of emitter with detectors. Most of the available detectors systems are intrusive where sensors or probes need to be placed within the analyzed processes and this will create disturbances in the current processes. This research are conducted in order to analyze and proved the capability of laser with Charge Coupled Device in an optical tomography system for detecting air bubbles exist in crystal clear water. Experiments in detecting moving air bubbles are conducted. The images of captured data are reconstructed based on filtered image of Linear Back Projection with Hybrid algorithms. As a conclusion, this research have successfully developed an optical tomography system that capable to capture the image and measure the diameter and velocity of rising air bubbles in a non-flowing crystal clear water.     

Correction of GPR wave velocity at different oblique angles between traverses and alignment of line objects in a common offset antenna setting

Estimation of ground penetrating radar's wave velocity in materials is a critical step to accurately estimate depth of embedded line objects in concrete structures, and wetness of material. Errors of velocity are defined as the deviations between the velocities obtained in various oblique angles and those obtained in the traverse normal to the object orientation in a common offset antenna setting. In this paper, we quantified and corrected the errors of such estimation. GPR traverses were designed to travel in various oblique angles θ (90°, 75°, 60° and 45°) relative to the steel bars at 5 cover depths (55 mm, 85 mm, 115 mm, 145 mm and 175 mm). GPR wave velocity at any position within the lateral detection range of steel bars was measured with simple trigonometry in a semi-automated in-house program. It was found that reduction of oblique angles (i.e. θ<90°) causes flatter hyperbolic reflections and the associated errors of velocity can be as much as 30% in the case of an oblique angle 45° before correction. Such errors were corrected after re-scaling the horizontal travel distance with a multiplication factor of sin θ.     

Beam shaping to enhance zero group velocity Lamb mode generation in a composite plate and nondestructive testing application

Zero group velocity (ZGV) Lamb modes have already shown their potential in nondestructive testing applications as they are sensitive to the sample structural characteristics. In this paper, we first consider an aluminum sample to validate a method based on the beam shaping of the generation laser. This method is proven to enhance ZGV Lamb modes in aluminum, and then advantageously applied to a composite material plate. Finally, based on the proposed method, scanning the sample over healthy and flawed zones demonstrates the ability to detect subsurface flaws.     

气垫闭锁机构的设计与计算

针对客户对应用于大型覆盖件零件拉深工艺的多连杆压力机提出的气垫具有闭锁及下拉功能的要求,即使滑块到达下死点时气垫被锁住不能上升,同时还能继续下行一段距离确保气垫顶杆与制件脱离以保证安全。通过对原有气垫结构的改进,设计闭锁机构,满足客户要求,完善产品功能。     

薛村矿2号煤最短自然发火期的研究

在前人研究的基础上，对薛村矿2号煤取样进行了升温氧化实验，测定了升温过程中各种气体的生成量。并根据生成这些气体的键能值计算了氧化升温过程中的放热量，再由DSC实验测定的不同温度下煤的比热容，分段计算了达到临界温度需要的时间，进而确定了煤层的最短自然发火期，测定结果与实际统计的自然发火期比较符合。     

固液离心泵的理论、设计及性能

介绍了固液离心泵的两相流速度比设计理论、结构特性及性能参数。     

Online Wavelet Complementary velocity Estimator

In this paper, we have proposed a new online Wavelet Complementary velocity Estimator (WCE) over position and acceleration data gathered from an electro hydraulic servo shaking table. This is a batch estimator type that is based on the wavelet filter banks which extract the high and low resolution of data. The proposed complementary estimator combines these two resolutions of velocities which acquired from numerical differentiation and integration of the position and acceleration sensors by considering a fixed moving horizon window as input to wavelet filter. Because of using wavelet filters, it can be implemented in a parallel procedure. By this method the numerical velocity is estimated without having high noise of differentiators, integration drifting bias and with less delay which is suitable for active vibration control in high precision Mechatronics systems by Direct Velocity Feedback (DVF) methods. This method allows us to make velocity sensors with less mechanically moving parts which makes it suitable for fast miniature structures. We have compared this method with Kalman and Butterworth filters over stability, delay and benchmarked them by their long time velocity integration for getting back the initial position data.     

液体射流泵内流场的数值模拟

借助CFDesign 9.0软件平台,基于有限体积法计算连续相控制方程,结合多相流模型中的流体体积模型以及可实现κ-ε湍流模型,对液体射流泵全流场进行了三维数值模拟。     

HLA在火炮速度参数测试仿真中的应用

该文针对常规靶场武器测试的现状,提出了应用HLA技术进行仿真试验,为建立最优的测试方案提供帮助。文章提出了基于HLA的火炮速度参数测试仿真系统的框架。对仿真执行过程进行了阐述;详细论述了仿真系统中火炮炮弹盟员的建模、两种测速雷达盟员的建模;对联盟的开发过程进行了论述,举例说明丁如何进行对象类和交互类设计,如何编写盟员程序;最后,阐述了根据测试方案建立分布交互仿真系统,进行虚拟试验来检验测试方案的优劣,依据系统的仿真结果,给出了对制定的测试方案的评价方法。     

铜浮选专家控制系统设计与应用

针对国内某选矿厂铜浮选工艺泡沫速率不稳定,精矿品位波动大,回收率不理想等特点,设计了一套浮选专家控制系统,该系统结合泡沫影像分析技术,在线品位分析技术,PID控制与模糊逻辑控制技术。系统架构简明合理,逻辑层次清晰有效,投入运行一段时间后,在不同原矿品位前提下,都能实现稳定泡沫速率,减少精矿品位波动,提高回收率等指标优化,同时药剂添加量也有明显减少。这表明该系统运行效果良好,值得应用推广。