Research on Airborne Blue-Green Laser Anti-Submarine Technology

2011 ◽  
Vol 480-481 ◽  
pp. 590-594 ◽  
Author(s):  
Hai Yan Li
Keyword(s):  
Basic Principle ◽  
Green Laser ◽  
Maximum Depth ◽  
New Method ◽  
Detection Accuracy ◽  
Shallow Sea ◽  
Work Process ◽  
Marine Technology ◽  
Laser Transmitter ◽  
Depth Detection

Submarine is applied widely in naval war and this urges navy in every country develop anti-submarine equipments and weapons. The airborne blue-green laser anti-submarine becomes a new method. In this paper, the basic principle of airborne blue-green laser anti-marine technology and work process are introduced firstly, and then the system constituents are analyzed. The performance demand of laser transmitter, receiver and maximum depth and depth detection accuracy are discussed. The results proved that detecting submarine by laser is efficient, especially in the shallow sea which is only several decameters deep.

scholarly journals A Research on Landslides Automatic Extraction Model Based on the Improved Mask R-CNN

2021 ◽  
Vol 10 (3) ◽  
pp. 168
Author(s):  
Peng Liu ◽  
Yongming Wei ◽  
Qinjun Wang ◽  
Jingjing Xie ◽  
Yu Chen ◽  
...  
Keyword(s):  
Remote Sensing Data ◽  
Extraction Methods ◽  
New Method ◽  
Detection Accuracy ◽  
Sufficient Information ◽  
Automatic Extraction ◽  
Emergency Rescue ◽  
Feature Pyramid ◽  
High Level ◽  
Extraction Model

Landslides are the most common and destructive secondary geological hazards caused by earthquakes. It is difficult to extract landslides automatically based on remote sensing data, which is import for the scenario of disaster emergency rescue. The literature review showed that the current landslides extraction methods mostly depend on expert interpretation which was low automation and thus was unable to provide sufficient information for earthquake rescue in time. To solve the above problem, an end-to-end improved Mask R-CNN model was proposed. The main innovations of this paper were (1) replacing the feature extraction layer with an effective ResNeXt module to extract the landslides. (2) Increasing the bottom-up channel in the feature pyramid network to make full use of low-level positioning and high-level semantic information. (3) Adding edge losses to the loss function to improve the accuracy of the landslide boundary detection accuracy. At the end of this paper, Jiuzhaigou County, Sichuan Province, was used as the study area to evaluate the new model. Results showed that the new method had a precision of 95.8%, a recall of 93.1%, and an overall accuracy (OA) of 94.7%. Compared with the traditional Mask R-CNN model, they have been significantly improved by 13.9%, 13.4%, and 9.9%, respectively. It was proved that the new method was effective in the landslides automatic extraction.

scholarly journals Detection of Breaking Waves in Single Wave Gauge Records of Surface Elevation Fluctuations

2019 ◽  
Vol 36 (9) ◽  
pp. 1863-1879 ◽  
Author(s):  
Dan Liberzon ◽  
Alexandru Vreme ◽  
Sagi Knobler ◽  
Itamar Bentwich
Keyword(s):  
Water Waves ◽  
Cost Effective ◽  
Breaking Waves ◽  
Recognition Algorithm ◽  
New Method ◽  
Surface Elevation ◽  
Detection Accuracy ◽  
Single Wave ◽  
Accurate Detection ◽  
Forced Waves

We report the development of a new method for accurate detection of breaking water waves that addresses the need for an accurate and cost-effective method that is independent of human decisions. The new detection method, which enables the detection of breakers using only surface elevation fluctuation measurements from a single wave gauge, supports the development of a new method for research relating to water waves and wind–wave interactions. According to the proposed method, detection is based on the use of the phase-time method to identify breaking-associated patterns in the instantaneous frequency variations of surface elevation fluctuations. A wavelet-based pattern recognition algorithm is devised to detect such patterns and provide accurate detection of breakers in the examined records. Validation and performance tests, conducted using both laboratory and open-sea data, including mechanically generated and wind-forced waves, are reported as well. These tests allow us to derive a set of parameters that assure high detection accuracy rates. The method is shown to be capable to achieve a positive detection rate exceeding 90%.

Research on Screw Thread Form Based on Non-Contact Measurement

2011 ◽  
Vol 101-102 ◽  
pp. 593-596
Author(s):  
Shao Feng Shen ◽  
Xian Cheng Wang ◽  
Jun Hua Chen
Keyword(s):  
Measurement Accuracy ◽  
Optical Axis ◽  
Optical Field ◽  
New Method ◽  
Detection Accuracy ◽  
Screw Thread ◽  
Characteristic Parameters ◽  
The Real ◽  
Contact Measurement ◽  
High Skill

There is a problem with non-contact measurement and detection, which reduces its measurement accuracy. Methods developed for measuring and inspecting screw thread characteristic parameters usually using a camera, which is controlled to scan the projection of thread in the parallel optical field to obtain thread images. However, with the block of screw line on the projection of the real thread form, it is impossible to acquire the real thread form from images. The traditional way is adjusting the optical axis to a suitable angle with the thread axis to acquire the real thread form projection, which has some problems, such as time consuming, high skill of operator, high-precision equipment for adjustment, inaccuracy, and so on. Hence, a new method through digital image calibration is presented. The results of relevant simulation indicated the feasibility of this new method, which improves thread measurement and detection accuracy.

Overview of Micro-Force Sensing Methods

2013 ◽  
Vol 462-463 ◽  
pp. 25-31 ◽  
Author(s):  
Chao Zhe Ma ◽  
Jin Song Du ◽  
Yi Yang Liu ◽  
Yun Kai Chu
Keyword(s):  
Basic Principle ◽  
Automatic Processing ◽  
Paper Analysis ◽  
Force Sensing ◽  
Detection Accuracy ◽  
Important Research ◽  
High Quality ◽  
Micro Assembly ◽  
Processing Level

At present, reliable micro-force sensing is one of the most important research for micromanipulation and micro-assembly. Six kinds of methods to detect micro-force are described in this paper. Analysis of the basic principle and detection accuracy of each sensing method, and applications in micro-assembly and micromanipulation are briefly introduced. The purpose of this paper is to be useful to provide some references for scholars engaging in the micro-force sensing, which in turn promotes automatic processing level of micro-assembly and micromanipulation to reliably manufacture micro devices of high quality.

Kinematics Simulation and Design of Work Elements of Demolition Robot Based on Virtual Prototype

2012 ◽  
Vol 479-481 ◽  
pp. 1565-1569 ◽  
Author(s):  
Gui Mao Si ◽  
Jun Wei Liu ◽  
Jun Zhang ◽  
Xiao Jing Meng
Keyword(s):  
3D Model ◽  
Simulation Experiment ◽  
Virtual Prototype ◽  
Maximum Depth ◽  
New Method ◽  
Interference Detection ◽  
Maximum Height ◽  
Maximum Radius ◽  
Kinematics Simulation ◽  
Work Envelope

Work Scope is key performance to the Demolition robot and is also a major factor consider to the users. CATIA and ADAMS were employed to design the 3D model and do the kinematics simulation to complete the design of work element of Demolition Robot. Parameters of assembly and interference detection of the 3D model was checked in the CATIA before taking the kinematics simulation experiment. The simulated result indicated that maximum radius, maximum depth and maximum height of Demolition Robot could be obtained, variance of forces at key articulated points and scope of work envelope diagram were presented, which provides a new method to analyze and design Demolition Robot.

scholarly journals A New Method for Detecting Compensation Hole Parameters of Automobile Brake Master Cylinder Based on Machine Vision

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Changfu Zhao ◽  
Hongchang Ding ◽  
Guohua Cao ◽  
Ying Zhang
Keyword(s):  
Hough Transform ◽  
New Method ◽  
Zernike Moment ◽  
Machining Accuracy ◽  
Detection Accuracy ◽  
Master Cylinder ◽  
Fast Detection ◽  
Detection Technology ◽  
Center Position ◽  
Detection Speed

The machining accuracy of the compensation hole of the automobile brake master cylinder directly determines the safety of the automobile and the reliability of parking. How to detect the parameters of the compensation hole with high precision becomes a crucial issue. In this paper, by analyzing the principle of Hough transform detection technology and several optimization algorithms, a new method combining Zernike moment and improved gradient Hough transform is proposed to detect the circular hole parameters. The simulation experiment shows that the proposed algorithm satisfies 0.1 pixels in the coordinate detection of the center position, and the radius detection accuracy is 0.05 pixels, with fast detection speed and good robustness. Compared with the random Hough transform algorithm and the gradient Hough transform algorithm, the algorithm proposed in this paper has higher detection accuracy, faster detection speed, and better robustness, which meets the online detection accuracy requirements of the brake master cylinder compensation hole.

A New Method for Full Shaking Force Balancing of Planar Linkages by a Few Finite Positions

1996 ◽  
Author(s):  
Ting-Li Yang ◽  
Ming Zhang ◽  
Qiong Jin
Keyword(s):  
Basic Principle ◽  
Linear Equations ◽  
New Method ◽  
System Of Linear Equations ◽  
Position Data ◽  
Minimum Number ◽  
Spatial Linkages ◽  
Planar Linkages

Abstract A new method called “Finite Position Method” is presented in this paper. By means if this method, it is easy to obtain the condition for full shaking force balancing of planar linkages (FSFBPL), to derive the counter theorem and the minimum number of counterweights. The balancing condition could be generated easily via establishing and solving a system of linear equations using a few finite position data of the linkage. The basic principle of this method could be expanded to the study for balancing theory of the spatial linkages.

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