Source Location of Cracks in a Working Roll of the Temper Mill with Acoustic Emission Technology

2012 ◽  
Vol 572 ◽  
pp. 343-347
Author(s):  
Qiao Qiao Lu ◽  
Min Li ◽  
Xiao Jing Wang
Keyword(s):  
High Efficiency ◽  
Static Pressure ◽  
Detection Method ◽  
Time Of Arrival ◽  
Strip Steel ◽  
Localization Method ◽  
Roll Body ◽  
Crack Location ◽  
External Loads ◽  
Acoustic Emission Technology

The application of the temper mill is mainly to improve the mechanical property of strip and to rectify the shape of strip. The working roll of a temper mill is often running with alternating load that prone to lead to faults such as wear, crack and spalling, which cause severe quality problems in the production of strip steel. In order to gain the information of crack's location and depth, the proposed method employs two circles of AE sensors along the direction of the roll body and use static pressure as external loads together with time-of-arrival localization method to detect the exact location of the roll cracks. The positioning results confirmed the validity of the proposed method with the post-repair grinding data. The advantage of this detection method is not requiring the full roll body scan point by point. With only one layout of the sensors, the method can detect the crack location with high efficiency and good real-time property.

A Simple Guidance Template-Based Defect Detection Method for Strip Steel Surfaces

2019 ◽  
Vol 15 (5) ◽  
pp. 2798-2809 ◽  
Author(s):  
Heying Wang ◽  
Jiawei Zhang ◽  
Ying Tian ◽  
Haiyong Chen ◽  
Hexu Sun ◽  
...  
Keyword(s):  
Defect Detection ◽  
Detection Method ◽  
Strip Steel ◽  
Steel Surfaces

scholarly journals Using Improved Edge Detection Method to Detect Mining-Induced Ground Fissures Identified by Unmanned Aerial Vehicle Remote Sensing

2021 ◽  
Vol 13 (18) ◽  
pp. 3652
Author(s):  
Duo Xu ◽  
Yixin Zhao ◽  
Yaodong Jiang ◽  
Cun Zhang ◽  
Bo Sun ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Edge Detection ◽  
Unmanned Aerial Vehicle ◽  
Field Experiments ◽  
High Efficiency ◽  
Detection Method ◽  
Laplacian Operator ◽  
Ground Fissures ◽  
Aerial Vehicle ◽  
Edge Detection Method

Information on the ground fissures induced by coal mining is important to the safety of coal mine production and the management of environment in the mining area. In order to identify these fissures timely and accurately, a new method was proposed in the present paper, which is based on an unmanned aerial vehicle (UAV) equipped with a visible light camera and an infrared camera. According to such equipment, edge detection technology was used to detect mining-induced ground fissures. Field experiments show high efficiency of the UAV in monitoring the mining-induced ground fissures. Furthermore, a reasonable time period between 3:00 a.m. and 5:00 a.m. under the studied conditions helps UAV infrared remote sensing identify fissures preferably. The Roberts operator, Sobel operator, Prewitt operator, Canny operator and Laplacian operator were tested to detect the fissures in the visible image, infrared image and fused image. An improved edge detection method was proposed which based on the Laplacian of Gaussian, Canny and mathematical morphology operators. The peak signal-to-noise rate, effective edge rate, Pratt’s figure of merit and F-measure indicated that the proposed method was superior to the other methods. In addition, the fissures in infrared images at different times can be accurately detected by the proposed method except at 7:00 a.m., 1:00 p.m. and 3:00 p.m.

scholarly journals A Hierarchical Voting Based Mixed Filter Localization Method for Wireless Sensor Network in Mixed LOS/NLOS Environments

Sensors ◽  
2018 ◽  
Vol 18 (7) ◽  
pp. 2348 ◽  
Author(s):  
Yan Wang ◽  
Jinquan Hang ◽  
Long Cheng ◽  
Chen Li ◽  
Xin Song
Keyword(s):  
Kalman Filter ◽  
Wireless Sensor Network ◽  
Sensor Network ◽  
Unscented Kalman Filter ◽  
Rapid Development ◽  
Mobile Node ◽  
Wireless Sensor ◽  
Line Of Sight ◽  
Time Of Arrival ◽  
Localization Method

In recent years, the rapid development of microelectronics, wireless communications, and electro-mechanical systems has occurred. The wireless sensor network (WSN) has been widely used in many applications. The localization of a mobile node is one of the key technologies for WSN. Among the factors that would affect the accuracy of mobile localization, non-line of sight (NLOS) propagation caused by a complicated environment plays a vital role. In this paper, we present a hierarchical voting based mixed filter (HVMF) localization method for a mobile node in a mixed line of sight (LOS) and NLOS environment. We firstly propose a condition detection and distance correction algorithm based on hierarchical voting. Then, a mixed square root unscented Kalman filter (SRUKF) and a particle filter (PF) are used to filter the larger measurement error. Finally, the filtered results are subjected to convex optimization and the maximum likelihood estimation to estimate the position of the mobile node. The proposed method does not require prior information about the statistical properties of the NLOS errors and operates in a 2D scenario. It can be applied to time of arrival (TOA), time difference of arrival (TDOA), received signal (RSS), and other measurement methods. The simulation results show that the HVMF algorithm can efficiently reduce the effect of NLOS errors and can achieve higher localization accuracy than the Kalman filter and PF. The proposed algorithm is robust to the NLOS errors.

Calibration Based on a Simplified D-ToA Localization Method for the Video Sensor Nodes on the Metro Vehicle

2012 ◽  
Vol 263-266 ◽  
pp. 963-968
Author(s):  
Xiao Yang Yao ◽  
Si Yuan Li ◽  
Jun Tang ◽  
Wei Feng Yang ◽  
Jian Xiao Chen
Keyword(s):  
Video Surveillance ◽  
Good Accuracy ◽  
Sensor Nodes ◽  
Time Of Arrival ◽  
Localization Method ◽  
Video Sensor ◽  
Video Sensor Nodes

The onboard video surveillance/CCTV system and the concept of calibration have been analyzed. The simplified Differential Time of Arrival localization method (D-ToA) has been proposed and applies to the calibration of the video sensor nodes. The experiment results show that the D-ToA has a good accuracy and satisfies the requirements of the calibration of the video sensor nodes.

scholarly journals Characteristics and Construction Technology Analysis of Static Pressure Prestressed Pipe Piles in Construction Engineering

2018 ◽  
Vol 2 (3) ◽  
Author(s):  
Cuipeng Wu
Keyword(s):  
Pile Foundation ◽  
High Efficiency ◽  
Static Pressure ◽  
Rapid Development ◽  
Low Noise ◽  
Building Construction ◽  
Construction Technology ◽  
Construction Work ◽  
Construction Engineering ◽  
Pipe Pile

The development of urbanization has led to an increase in the number and scale of construction projects and the types of building construction engineering are getting advance and diverse due to the rapid development of technology. One of them is the static pressure prestressed pipe pile which is the most common used technology in modern building construction work.  It is mainly used for pile foundation in construction work and it has the advantages in less pollution, low noise and high efficiency compared to the traditional pile foundation. Study on the characteristics of static pressure prestressed pipe pile must be carried out and strengthened the research in order to increase the effectiveness and quality of static pressure prestressed pipe pile on construction works. This paper is mainly to analyzed the characteristic and construction technology of static pressure prestressed pipe piles on building construction work.

Applying Constant Pressure Unit to Ductile Mode Cutting of Hard and Brittle Materials

2013 ◽  
Vol 7 (3) ◽  
pp. 278-284 ◽  
Author(s):  
Kunitaka Kuriyama ◽  
◽  
Masahiko Fukuta ◽  
Katsuhiko Sekiya ◽  
Keiji Yamada ◽  
...  
Keyword(s):  
Cutting Forces ◽  
High Efficiency ◽  
Static Pressure ◽  
Constant Pressure ◽  
Brittle Materials ◽  
Ductile Mode ◽  
Hard And Brittle Materials ◽  
Ductile Mode Cutting ◽  
Pressure Unit ◽  
Increasing Demand

It is strongly wished that hard and brittle materials could be used in a wide variety of fields because of their great material characteristics. For now, however, minute profiling or high-efficiency cutting of these materials has not yet been put into practice due to their hardness. At the same time, there have been numerous reports available on ductile mode cutting for hard and brittle materials in response to the increasing demand. Very smoothly finished surfaces can reportedly be generated through the work of a material removal mechanism similar to plastic deformation, done by microminiaturizing cutting units with the sharp cutting edges of tools. Because of the extremely narrow ductile mode regions, however, forced cutting processing, which includes cutting work, demands extremely high motion performance or rigidity of machine tools, and this makes it difficult to realize stable ductile mode cutting. On the other hand, pressure cutting processing similar to polishing is known to be capable of producing extremely smooth finished surfaces on hard and brittle materials; this suggests that we could realize stable ductile mode cutting that will always create the same depths of cut by controlling the insertion forces on the tools. In this paper, in order to realize stable ductile mode cutting, we have devised and prototyped a constant pressure cutting device which can regulate cutting forces by regulating supply pressure with air static pressure bearings. We have investigated the relationships between the pressure supplied in the cutting direction and the cutting forces in order to get static pressure characteristics of the prototype device. We have also carried out experiments to cut hard and brittle materials with the prototype constant pressure cutting device mounted on the tool post of an ultraprecision machine tool to prove the effectiveness of the constant pressure cutting device for the ductile mode cutting of hard and brittle materials.

scholarly journals Design of High Efficiency Blowers for Future Aerosol Applications

2009 ◽  
Author(s):  
Raman Chadha ◽  
Gerald L. Morrison ◽  
Andrew R. McFarland
Keyword(s):  
Flow Rate ◽  
High Efficiency ◽  
Static Pressure ◽  
Pressure Rise ◽  
Electrical Energy ◽  
Design Flow ◽  
Preliminary Design ◽  
Aerosol Sampling ◽  
Wall Functions ◽  
Low Efficiency

High efficiency air blowers to meet future portable aerosol sampling applications were designed, fabricated, and their performance evaluated. A preliminary blower design based on specific speed was selected, modeled in CFD, and the flow field simulated. This preliminary blower size was scaled in planar and axial directions, at different rpm values, to set the Best Efficiency Point (BEP) at a flow rate of 100 L/min (1.67×10−3 m3/s @ room conditions) and a pressure rise of 1000 Pa (4″ WC). Characteristic curves for static pressure rise versus air flow rate through the impeller were generated. Experimentally measured motor/blower combination efficiency (ηEXP) for the preliminary design was around 10%. The low value was attributed to the low efficiency of the D.C. motor used (Chadha, 2005). CFD simulations using the κ–ε turbulent model and standard wall function (non-equilibrium wall functions) approach overpredicted the head values. Enhanced wall treatment under-predicted the head rise but provided better agreement with experimental results. The static pressure rise across the final blower is 1021 Pa at the design flow rate of 100 L/min. Efficiency value based on measured static pressure rise value and the electrical energy input to the motor (ηEXP) is 26.5%, a 160% improvement over the preliminary design.

Numerical Simulation and Flow Field Measurement of High Efficiency Axial-Flow Pump

2009 ◽  
Author(s):  
De-sheng Zhang ◽  
Wei-dong Shi ◽  
Bin Chen ◽  
Xing-fan Guan
Keyword(s):  
Rotor Blade ◽  
Radial Direction ◽  
High Efficiency ◽  
Static Pressure ◽  
Axial Flow ◽  
Rotor Blades ◽  
Experimental Results ◽  
Meridional Velocity ◽  
Axial Flow Pump ◽  
Flow Pump

In order to analyze the flow characteristics of a high efficiency axial-flow pump, the behavior of the flow in an adjustable axial-flow pump bas been analyzed by numerical simulations of the entire stage based on Fluent software. The prediction data shows agreement with the experimental results. Numerical results show that the static pressure on pressure side of rotor blades increases slightly at radial direction, and remains almost constant in circumferential direction at design conditions, while it increases gradually from inlet to exit on suction side along the flow direction. The static pressure, total pressure and velocity at inlet, rotor blade exit and stator outlet were measured by five-hole probe. The experimental results show, inlet flow is almost axial and the prerotation is very small at design conditions. The meridional velocity and circulation distributions are almost uniform at rotor blades exit at design condition. The residual circulation still exists at downstream of stator, and the absolute flow angle at radial direction is almost consistent at design conditions, but Cu increases linearly from hub to tip at small flow rate conditions. To determine the influence of the hub leakage, a contrast experiment was accomplished. The measurement results show that hub leakage results in the decrease of efficiency, and the meridional velocity and circulation at rotor blade exit, especially near hub leakage region are influenced by the leakage.

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