This paper describes a simple and sensitive method for determining estrogen (E1), ß-estradiol (E2), estriol (E3), 17¿-ethynylestradiol (EE2), diethylstilbestrol (DES), 4-tert-octyphenol (OP), 4-n-nonylphenol...
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This paper describes a simple and sensitive method for determining estrogen (E1), ß-estradiol (E2), estriol (E3), 17¿-ethynylestradiol (EE2), diethylstilbestrol (DES), 4-tert-octyphenol (OP), 4-n-nonylphenol (NP), nonylphenol mono- to di-ethoxylates (NP1EO, NP2EO), bisphenol A (BPA) in water samples of Songhua River in China. The survey was preceded by selecting extraction methods, clean-up procedures for the simultaneous GC-MS determination of all examined EDCs in water samples. The limits of detection (LOD) of all the target compounds were 0.052~1.5ng/L. The concentration levels of five steroidal estrogens, E1, E2, E3, EE2, DES in water samples of Songhua River were ND.~15.78ng/L, ND.~6.63ng/L, ND., ND.~34.70ng/L and ND.~6.75ng/L, respectively and the concentration levels of five phenolic endocrine disrupting chemicals, OP, 4-n-NP, NP1EO, BPA and NP2EO, in water samples were 1.84~15.28 ng/L, 0.18~6.82 ng/L, 6.06~126.09 ng/L, 8.84~329.47 ng/L and 4.68~123.30 ng/L, respectively.
The paper puts forward a new concept of the Satellite On-Orbit Self-Servicing using vision. In order to verify this concept, a prototype vision system has been presented by integrating vision techniques. Cooperative o...
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Traditional methods of residual stress measurement are generally destructive or semi-destructive, as well as expensive, time-consuming and complex to implement. With the new development of welded structure, traditiona...
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Traditional methods of residual stress measurement are generally destructive or semi-destructive, as well as expensive, time-consuming and complex to implement. With the new development of welded structure, traditional methods can not satisfy the need of full life task management. So the acoustical theory is introduced, since the ultrasonic technique provides a useful nondestructive tool in the evaluation of stresses. In this study an ultrasonic stress measurement experimental installation is established, which consists of a special transducer, a signal emission unit and a signal recipient processing unit. Longitudinal critically refracted wave is selected as the measurement wave mode. The supporting software is programmed by Labview software. The longitudinal residual stress and transverse residual stress of twin wire welded plate are measured by this installment, in which the measuring process is real-time, quick and nondestructive. The experiment results indicate that the system can satisfy the need of life evaluation for welded structure. The system is light and portable.
In order to analyze the performance of lunar rover, drawbar pull and motion resistance are analyzed in this paper based on terramechanics. The relationships between configuration parameters (like wheel width, wheel ba...
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The variation of joint groove size during tungsten inert gas （TIG） welding will result in the non-uniform fill of deposited metal. To solve this problem, an adaptive fill control system was developed based on laser ...
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The variation of joint groove size during tungsten inert gas （TIG） welding will result in the non-uniform fill of deposited metal. To solve this problem, an adaptive fill control system was developed based on laser vision sensing. The system hardware consists of a modular development kit （MDK） as the real-time image capturing system, a computer as the controller, a D/A conversion card as the interface of controlled variable output, and a DC TIG welding system as the controlled device. The system software is developed and the developed feature extraction algorithm and control strategy are of good accuracy and robustness. Experimental results show that the system can implement adaptive fill of melting metal with high stability, reliability and accuracy. The groove is filled well and the quality of the weld formation satisfies the relevant industry criteria.
The characteristics of micro electro mechanical system (MEMS) assembling and packaging process are analyzed, and the development status of machining devices is given. According to the characteristics of MEMS industry ...
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The characteristics of micro electro mechanical system (MEMS) assembling and packaging process are analyzed, and the development status of machining devices is given. According to the characteristics of MEMS industry development, the key techniques of MEMS assembling and packaging devices are described, including database of technological parameters, fast precision positioning, modular working tools, fast micro-vision, flexible clamping and automatic material handling techniques. The composition structure and working principle of an anodized bonding device for MEMS pressure sensor and a wire bonding device are introduced, and some experimental results are given. At last, the development trend of MEMS assembling and packaging techniques and devices are discussed.
A set of three-dimensional profile detection system based on machine vision is designed for profile detection of parts on product line. This system mainly consists of a data acquisition module based on CCD (charge cou...
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A set of three-dimensional profile detection system based on machine vision is designed for profile detection of parts on product line. This system mainly consists of a data acquisition module based on CCD (charge coupled device), an embedded data processing module based on FPGA (field programmable gate array), a data transmitting module based on USB (universal serial bus), and an image display module based on OpenGL. The structure of this system is very compact, and it can reach higher resolution for parts moving in high speed on product line. Data processing module can run many arithmetics in it, therefore we can choose better. USB data transmitting interface offers faster data transmitting speed, and allows plugging and pulling device when the computer is powered on, so it avoids disadvantages of PCI (peripheral component interconnection) interface which is based on slot, and needs opening of the chassis. Display module based on VC shows detection result in graphic mode, it is more direct and conveniently realizes intercommunication between people and computer.
Considering that the trajectory and the stance of frog jumping movement are the basis of the research on the biological jumping mechanism of biomimetic robot design, a new method of trajectory extraction from animal&#...
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Considering that the trajectory and the stance of frog jumping movement are the basis of the research on the biological jumping mechanism of biomimetic robot design, a new method of trajectory extraction from animal's movement is presented. With the help of the proposal, views from both sides or from the top of the frog moving can be captured simultaneously. And the 3D information was obtained after the correction for the perspective effect and the reduction of error produced by coefficient. To overcome the shortcoming of large amount of calculation, a program is designed to deal with the video images. And finally the curve of the position, the velocity and the acceleration of each point and the angle of each joint of frog are exported. The results of experiment and analysis show that the new method could be employed to develop and control a jumping robot.
A new method which can segment gesture from general and complex backgrounds is introduced. First, this method deals the gesture picture which is get in the general background by convolute filter, and verifies clusteri...
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A new method which can segment gesture from general and complex backgrounds is introduced. First, this method deals the gesture picture which is get in the general background by convolute filter, and verifies clustering character of complexion, then by the complexion and geometry characters of the gestures, this method segments gestures from the backgrounds successfully. At last, by experiments of different backgrounds and eight different gestures, the validity of the method is verified, static state identify rate is 99%.
A method of feature extraction which is composed of invariable moment functions and Principal Component Analysis (PCA) is presented in order to recognize and classify the surface defects of strips. First, a 22-dimensi...
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A method of feature extraction which is composed of invariable moment functions and Principal Component Analysis (PCA) is presented in order to recognize and classify the surface defects of strips. First, a 22-dimensional eigenvector which was invariable was extracted from images when the image was translated, scaled and rotated. And then, in order to improve the efficiency of classification, PCA was applied to reduce the dimension of the eigenvector. As a result, the 4-dimensional eigenvector was obtained. Finally, using these eigenvectors as input, weights and thresholds of the BP neural network were trained for the purpose of defect classification. Experimental results show that the average efficiency of the correct identification can reach 85%, and it's fit for the application for detection of surface defects of strips.
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