Local and global Gabor features for raised character recognition

Conventional Gabor representation and its extracted features often yield a fairly poor performance in extracting the invariance features of objects.To address this issue,a global Gabor representation method for raised characters pressed on label is proposed in this paper,where the representation only requires few summations on the conventional Gabor filter responses.Features are then extracted from these new representations to construct the invariant features.Experimental results clearly show that the obtained global Gabor features provide good performance in rotation,translation,and scale invariance.Also,they are insensitive to illumination conditions and noise changes.It is proved that Gabor filters can be reliably used in low-level feature extraction in image processing and the global Gabor features can be used to construct robust invariant recognition system.     

Finger crease pattern recognition using Legendre moments and principal component analysis

The finger joint lines defined as finger creases and its distribution can identify a person. In this paper, we propose a new finger crease pattern recognition method based on Legendre moments and principal component analysis (PCA). After obtaining the region of interest (ROI) for each finger image in the preprocessing stage, Legendre moments under Radon transform are applied to construct a moment feature matrix from the ROI, which greatly decreases the dimensionality of ROI and can represent principal components of the finger creases quite well. Then, an approach to finger crease pattern recognition is designed based on Karhunen-Loeve (K-L) transform. The method applies PCA to a moment feature matrix rather than the original image matrix to achieve the feature vector. The proposed method has been tested on a database of 824 images from 103 individuals using the nearest neighbor classifier. The accuracy up to 98.584% has been obtained when using 4 samples per class for training. The experimental results demonstrate that our proposed approach is feasible and effective in biometrics.     

A study of fringe pattern trace and analysis

In this paper,the gometric center and centroid method are suggested to tracecenter location of a close fringe pattern.The fringe pattern of the interferogram is analysed byusing the general Fourier method.The analytic accuracy is controlled by using P-test methodof statistics.The analytic accuracy and sampling speed of the fringe pattern depend on thequality of the interferogram and the numbers of the sampling points.     

Application of wavelet transform in feature extraction and pattern recognition of wideband echoes

1IntroductionThefeatureextractionofunderwaterobjectsfromactiveechoisadifficultproblem.Thereceivedsignalisaconvolutionofthetransmittedsignalwiththeimpulseresponseoftheob-jects,plusvariousadditivedisturbances,includingnoiseandresonance.Inordertorecognizetheobjectswehavetoextractimportantfeaturesfromtheechoes.Inrecentyearsmanymeth-odshavebeenproposed,andoneoftheapproachesistodeconvolvetheechotogettheimpuIseresponsesequenceoftheobject.Thisisoftenfollowedbyaparametermodelapproximationwhiletheestim…     

The methods for combining the information of various kinds of features in speech recognition

I.IntroductionUptonow,thefeaturesbasedonvariouskindsofspeechmodelshavebeenproposedoneafteranother,andtheirperformanceswereinvestigatedinmanyliteratureofspeechstudies[1ai3l.Mostoftheseinvestigationshavecomparedtheoverallperformanceofspeechrecognitionsys-temsthatapplydifferentfeatures,andthenchoseonefeaturetomakeuparecognitionsys-tem.Atfirst,usingfourfeatures-Iinearpredictivecoefficiellts(LPC),generalrefiectivecoefficients(GRC),LPCcepstralcoefficients(CEP)andLPCspectrums(LPCC),theperform…     

A multi-resolution wavelet algorithm for hand vein pattern recognition

A novel hand vein recognition algorithm is developed based on multi-resolution wavelet analysis.The texture feature of hand vein can be extracted by three-level wavelet decomposition.Furthermore,K- nearest neighbor(KNN)with support vector machines(SVM)and minimum distance classifier(MDC)are employed for feature matching.Finally,the experiments are respectively performed in identification and verification modes using Tianjin University(TJU)hand vein image database constructed by our group. The results show the feasibility and effectiveness of the proposed method.     

Fusion of visible and infrared imagery for face recognition

In recent years face recognition has received substantial attention, but still remained very challenging in real applications. Despite the variety of approaches and tools studied, face recognition is not accurate or robust enough to be used in uncontrolled environments. Infrared (IR) imagery of human faces offers a promising alternative to visible imagery, however, IR has its own limitations. In this paper, a scheme to fuse information from the two modalities is proposed. The scheme is based on eigenfaces and probabilistic neural network (PNN), using fuzzy integral to fuse the objective evidence supplied by each modality. Recognition rate is used to evaluate the fusion scheme. Experimental results show that the scheme improves recognition performance substantially.     

Geometric analysis of φ4 fields and Ising models. Parts I and II

We provide here the details of the proof, announced in [1], that ind>4 dimensions the (even) ⁴ Euclidean field theory, with a lattice cut-off, is inevitably free in the continuum limit (in the single phase regime). The analysis is nonperturbative, and is based on a representation of the field variables (or spins in Ising systems) as source/sink creation operators in a system of random currents — which may be viewed as the mediators of correlations. In this dual representation, the onset of long-range-order is attributed to percolation in an ensemble of sourceless currents, and the physical interaction in the ⁴ field — and other aspects of the critical behavior in Ising models — are directly related to the intersection properties of long current clusters. An insight into the criticality of the dimensiond=4 is derived from an analogy (foreseen by K. Symanzik) with the intersection properties of paths of Brownian motion. Other results include the proof that in certain respect, the critical behavior in Ising models is in exact agreement with the mean-field approximation in high dimensionsd>4, but not in the low dimensiond=2 — for which we establish the universality of hyperscaling.A. P. Sloan Foundation Research Fellow. Supported in part by the National Science Foundation Grant PHY-78-25390-A02     

Automated image processing algorithm for Young's fringe pattern analysis

An automatic of image processing for the analysis of Young's fringe pattern is proposed. A Young's fringe patttern is first FFT treated to get two patterns of 0 degree and 90 degree phase shifted. Regular two pattern shift algorithm is used to calculate the phase of the Young's pattern. One or two times of phase shift iteration are carried out to improve the phase. Then the phase is least square fitted to get a phase plane. The displacement magnitude and direction are eaasily induced from the phase plane. Because every step is full field treatment, very precise result is achieved. The algorithm is simple and easy to implement. Theory and experiment are presented to prove the proposal. A program is designed to execute the algorithm and the processing is automated by a Personal Computer with an image board.     

Comparative analysis of lasing performance of oxide-confined and proton-implanted vertical-cavity surface-emitting diode lasers

The comprehensive optical-electrical-thermal-recombination self-consistent VCSEL model is used to compare the performance of oxide-confined (OC) and proton-implanted (PI) VCSELs and to optimise their structures. Generally index-guided (IG) OC VCSELs demonstrate lower lasing thresholds whereas both gain-guided (GG) OC and PI ones manifest much better mode selectivity. Therefore, their either low-threshold IG or mode-selective GG versions may be intentionally used for different VCSEL applications. Lasing thresholds of OC IG VCSELs have been found to be very sensitive to the exact localisation of their thin oxide apertures, which should be shifted as close as possible towards the anti-node position. PI VCSELs, on the other hand, are simpler and cheaper in their manufacturing than OC ones. Although lower threshold currents are manifested by PI VCSELs with very thick implanted regions, lower threshold powers are achieved in these devices with much thicker upper unaffected layer used for the radial current flow from the ring contact towards the laser axis. Paradoxically poor thermal properties of PI VCSELs enable lower lasing thresholds of slightly detuned devices. To conclude, cheaper and mode-selective PI VCSELs may be used instead of OC ones in many of their applications provided ambient temperatures and laser outputs are not too high.     

Edge enhancement by using two-wave mixing and its application to pattern recognition

Coupling theory is employed to analyze coupling gain and a new optical system is proposed for image edge enhancement, in which the ordinarily discarded background light is recycled as a pump source to amplify the signal light. We demonstrate the principle of optical correlation and compare the discrimination capability of two kinds of correlators by computer simulation. The results show that edge enhancement preprocessing can improve discrimination capability effectively.     

Comparative Mössbauer analysis of iron compounds in soils of earth and certain soils of mars

The need for the comparative analysis of terrestrial soil-mineral systems and Martian rocks is shown for the first time by examples from concrete research results using Mössbauer spectroscopy. The proposed technique is effective in considering and studying the processes that occur in multicomponent natural objects. A method for dividing magnetic particles into cosmic and technogenic is advanced as a hypothesis.     

Correlation recognition for range image of laser radar

The target recognition of laser radar becomes hot research in recent years, because laser radar can produce high space resolution and collect rich target information, such as range image, intensity image and Doppler image. In the vertical detection of laser radar, the problem of in-plane target rotation invariance is firstly solved. In the paper, a new support vector machine (SVM) correlation filter is presented, which simultaneously has the attractive attributes of SVM and common correlation filter. Exploiting the idea of margin of separation maximization, the design criterion is produced. The filter is synthetic by the multiple training images which are generated by rotating one image. The real range images of laser radar are used to finish the correlation experiments. The results show that the filter is not sensitive to the noise, the correlation peak is changed slightly for the different testing images, and the precision of location is high. This design way can be used in other recognition fields.     

Beam pattern of sparse array for passive sonar

This work aims at sparse array without grating lobe for passive sonar, in order to increase frequency band of the passive sonar and reduce the cost. According to traditional method, the distance between two contiguous sensors in sonar array should be less than the wavelength of highest frequency of the signal; otherwise the grating lobe appears on beam pattern. The paper realizes that the conclusion of the grating lobe emergence it is not fit to the passive sonar due to the sine wave signal model in traditional method, in fact the input of passive sonar is random signal. Prom three aspect of the computer simulation, real passive sonar signal and theory analysis, it is revealed that the grating lobe does not appear on beam pattern when the distance between two contiguous sensors in passive sonar array is longer than wavelength of highest frequency. Whitening of the radiated noise can widen the frequency band, to ensure the beam pattern without the grating lobe. The conclusion of the paper is: if the band of radiated noise is wide enough (broader than 1 octave), that the wavelength of signal can be shorter than the distance between two contiguous sensors in passive sonar without grating lobe.     

Exact combinatorics of Bern-Kosower-type amplitudes for two-loop φ3 theory

Counting the contribution rate of a world-line formula to Feynman diagrams in (φ³ theory, we explain the idea of how to determine precise combinatorics of Bern-Kosower-like amplitudes derived from a bosonic string theory for N-point two-loop Feynman amplitudes. In this connection we also present a method to derive simple and compact world-line forms for the effective action.     

A Mach–Zehnder joint transform correlator with the simulated annealing algorithm for pattern recognition

A non-zero order joint transform correlator based on a Mach–Zehnder system is presented for optical pattern recognition. The reference function is yielded by simulated annealing algorithm. Additionally, in order to achieve global convergence, the cost function should be set appropriately. The reference function is successful for pattern recognition.     

Comparative theoretical analysis of continuous wave laser cutting of metals at 1 and 10 μm wavelength

We present a derivation and, based on it, an extension of a model originally proposed by V.G. Niziev to describe continuous wave laser cutting of metals. Starting from a local energy balance and by incorporating heat removal through heat conduction to the bulk material, we find a differential equation for the cutting profile. This equation is solved numerically and yields, besides the cutting profiles, the maximum cutting speed, the absorptivity profiles, and other relevant quantities. Our main goal is to demonstrate the model’s capability to explain some of the experimentally observed differences between laser cutting at around 1 and 10 μm wavelengths. To compare our numerical results to experimental observations, we perform simulations for exactly the same material and laser beam parameters as those used in a recent comparative experimental study. Generally, we find good agreement between theoretical and experimental results and show that the main differences between laser cutting with 1- and 10-μm beams arise from the different absorptivity profiles and absorbed intensities. Especially the latter suggests that the energy transfer, and thus the laser cutting process, is more efficient in the case of laser cutting with 1-μm beams.     

Comparative first-principle analysis of un-doped and V3+-doped α-ZnAl2S4 spinel

The experimental and theoretical studies of the optical properties of pure α-ZnAl₂S₄ and α-ZnAl₂S₄:V³⁺ crystals were carried out. The ab initio and crystal field calculations of the structural and optical properties of α-ZnAl₂S₄:V³⁺ were compared with the corresponding experimental data. It was shown that the lowest vanadium 3d states are located at about 1.36 eV above the valence band's top. The complete energy level scheme of the α-ZnAl₂S₄:V³⁺ system, which includes the host's electronic band structure and impurity ion's energy levels, was suggested on the basis of the performed calculations.     

Design and analysis of the optical transceiver for mobile atmospheric laser communication

The concept of mobile atmospheric laser communication (MALC) is introduced in this paper. Atmospheric attenuation, turbulence-induced scintillation and beam wander cause deep fades in the beam power and degrade the optical channel. The optical transceiver presented in this paper is designed for a MALC test system. Currently achievable hardware performance capabilities for the MALC terminals are used as input parameters to the analysis. A novel optical transceiver structure is designed. Link margin is analyzed using the MALC analysis software, our optical link analysis program. Data rate, bit-error rate, prime transmit