Advanced Materials Research Vol. 586

Abstract: According to the holographic optical theory, based on the method of rotating reference light polarization plane, through the simultaneous solution of light intensity equations transformed by the hologram, the digital holographic nondestructive testing of two-dimensional stress field is introduced. This technology does not require additional experimental means and numerical method for separate fringes, determining fringe order and solving stress. It is a convenient, accurate and non-destructive measurement of two-dimensional stress field. The paper first introduces the basic theory of digital holographic photo-elastic method, and then verifies it by experiments and simulation. Light intensity images are obtained through the comparative experiments and theoretical solutions. The results prove the strong feasibility of the method in experiments, and lay the foundation for further experimental study.

Abstract: The exhaust gas temperature correction for the change of air inlet temperature is the most significant correction for boiler performance test. However, in ASME and China GB standard, the regulations of the correction formulas are different, which brings about some misunderstanding in actual use. In this paper, the correction formulas are derived and analyzed. What’s more, the application conditions are summed up and described as follows. Firstly, the top and side of the air heater must be in good sealing ability, for which the air leakage can be ignored. Secondly, the air inlet temperature must be taken from the entrance of the air heater, but not from that of the forced draft fan. Finally, the air leakage of the air heater must stay the same before and after the correction. On this basis, a correction method is conducted, which takes the cold air temperature at the entrance of the forced draft fan as the air inlet temperature and can be applied under different air leakage ratios conditions. With the same form as the traditional one, the method mentioned above is easy to understand and has a positive meaning in handling such problems.

Abstract: A new method for measuring perpendicularity is developed in this paper, in which the non-diffracting beam that illuminates a pentagonal prism to produce the vertical reference is used as the straight-line reference and CCD is used as the sensor to gauge the position error to the references. Three evaluation algorithms of the perpendicularity error are also given in the paper. And furthermore, perpendicularity of a Coordinate Measuring Machine was measured by this method, which is easy to be operated. The results and analysis indicate that its working distance can be more than 15m while the precision can be less than±5μm/m.

Abstract: Focusing properties of a new kind of plasmonic lenses are investigated in the visible wavelength range through a subwavelength metallic chirped slit arrays which have the same depth but chirped widths. The chirped widths of slits are like a piece-wise-linear distribution which will be approximated by linearly increasing the width of a subwavelength feature and can build up a required phase front for focusing. We analyzed the focusing characteristics of different metallic lenses (silver and gold, respectively) with chirped widths that are obtained by generalizing the relevant phase delay for TE- and TM-polarized incident waves, for different f-numbers of lenses and for different material thickness, respectively. Meanwhile, the comparison of the metallic and dielectric lenses is also presented. The results of calculations show that, the metallic lenses are more sensitive to the polarization of incidence wave than that of dielectric lenses, and can get narrower full-width half-maximum (FWHM) beam width than that of dielectric lenses for TM-polarized incident waves, respectively. No matter which f-number we choose, the FWHM of dielectric lenses are higher than the plasmonic lenses, and the plasmonic lenses can get a higher focal resolution than dielectric lenses do. This kind of plasmonic lenses should have a good potential for applications in photonic and plasmonic integrated devices, sensing, and nano-optical manipulations, etc.

Abstract: In this paper, a novel image blind separation using adaptive multi-resolution independent component analysis is presented.This method separates mixed images based on quadratic function. The quadratic function can be interpreted as the time-frequency function or time-scale function, or other. According to the signal characteristics, we can choose the frequency resolution or scale resolution. The argorithm extends the separate technology from one dimensional domain to two dimensional domain,and it’s implement by adaptive procedure. The experimental result showed the method can be effective separation of mixed images. And it shows that the method is feasible.

Abstract: Through used Fuzzy Petri Net to set up the knowledge representation and reasoning rules, a Fuzzy Neural Petri Network (FNPN) method whose parameters can be trained by Neural Network was proposed in this paper. The experimental result indicated that, the Neural Network and the Petri net combination can make the fuzzy production rule systems more effective, and also can be applied to most practical Petri net models and fuzzy systems.

Abstract: In this paper a new strategy for real-time three-dimensional object capturing and mapping is proposed by using optical correlators. A spatial light modulator is applied in the new strategy. Owing to the properties of quickly parallel processing of optical correlation algorithm the technique can also implement real time object capturing and track, and, as for human body recognition the gesture of body parts can also be portrayed.

Abstract: ßIn this paper we propose a new kind of nonlinear and geometry driven subdivision scheme for curve interpolation. We introduce serval parameters in the new scheme.When the parameter ß is taken as 0, the new scheme presented in this paper regresses to the initial four point subdivision scheme, and when ß→∞ , the new scheme is convexity preserving. With proper choices of the subdßivision parameters,it can overcome the shortcoming of the initial four point subdivision scheme proposed.

Abstract: This paper describes a stroke-based handwriting analysis method in classifying handwritten Numeric characters by using a template-based approach. Writing strokes are variable from time to time, even when the writing character is same and comes from the same user. Writing strokes include the properties such as the number of the strokes, the shapes and sizes of them and the writing order and the writing speed. We describe here a template-based system using the properties of writing strokes for the recognition of online handwritten numeric characters. Experimental results show that within the 1500 numeric characters taken from 30 writers, the system got 97.84% recognition accuracy which is better than other systems shown by other literatures.

Abstract: The paper deals with numerical analysis of the process of roller leveling of long products. The problem of multiple elastic plastic bending is solved by a program in Matlab, which is based on the Finite Element Method. The aim is to provide a simple, user friendly tool, capable of quick and reliable analysis of the process without the necessity to work with large multipurpose FEM packages. Direct solution of the problem is formulated, starting from the roll intermeshing and product geometry. Roller loading, product deflection, curvature and plastification are the output parameters of the program. With fast and reliable solution of the direct problem, optimal setting of the leveling process will be sought in an iterative process.