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1

Comparative study on the classification methods for breast cancer diagnosis

Qiu Y., Zhou G., Zhao Q., Cichocki A.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2018

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Vol. 66, nr 6

841--848

EN

Digital mammography is one of the most widely used approaches for breast cancer diagnosis. Many researchers have demonstrated the superiority of machine learning methods in breast cancer diagnosis using different mammography databases. Since these methods often have different pros and cons, which may confuse doctors and researchers, an elaborate comparison and examination among them is urgently needed for practical breast cancer diagnosis. In this study, we conducted a comprehensive comparative study of the state-of-the-art machine learning methods that are promising in breast cancer diagnosis. For this purpose we analyze the largest mammography diagnosis database: Digital Database for Screening Mammography (DDSM). We considered various approaches for feature extraction including principal component analysis (PCA), nonnegative matrix factorization (NMF), spatial-temporal discriminant analysis (STDA) and those for classification including linear discriminant analysis (LDA), random forests (RaF), k-nearest neighbors (kNN), as well as deep learning methods including convolutional neural networks (CNN) and stacked sparse autoencoder (SSAE). This paper can serve as a guideline and useful clues for doctors who are going to select machine learning methods for their breast cancer computer-aided diagnosis (CAD) systems as well for researchers interested in developing more reliable and efficient methods for breast cancer diagnosis.

2

Investigation of Microstructures and Mechanical Properties of T92 Martensitic Steel/Super304 Austenitic Steel Weld Joints Made with Three Welding Consumables

Liang Z., Gui Y., Zhao Q.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 3

1249--1256

EN

The microstructures and mechanical properties of T92 martensitic steel/Super304 austenitic steel weld joints with three welding consumables were investigated. Three types of welding materials ERNiCr-3, ERNiCrCoMo-1and T-304H were utilized to obtain dissimilar welds by using gas tungsten arc weld (GTAW). The results show that heat affect zone (HAZ) of T92 steel consists of coarse-grained and fine-grained tempered martensites. The microstructures of joints produced from ERNiCrCoMo-1 consist of equiaxed dendrite and columnar dendrite grains, which are more complicated than that of ERNiCr-3. In the tensile tests, joints constructed from ERNiCrCoMo-1 and T-304H met the ASME standard. The highest fracture energy was observed in specimens with the welding material ERNiCrCoMo-1. Ni content in weld seam of ERNiCrCoMo-1 was highest, which was above 40%. In conclusion, the nickel alloy ERNiCrCoMo-1 was the most suitable welding material for joints produced from T92 martensitic steel/Super304 austenitic steel.

3

Fatigue Behavior and Mechanism of FV520B-I Owing to the Effect of Loading Frequency on the Fatigue Property in HCF and VHCF Regime

Wang J., Zhang Y., Shi B., Zhao Q., Sun Q., Zhang Z., Lu H.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 1

347--357

EN

Fatigue property of FV520B-I is affected by the ultrahigh loading frequency significantly, and the ultrasonic fatigue experimental data can’t be employed directly to analyze the fatigue failure in the actual remanufacturing engineering. However few theories about the effect of loading frequency on the fatigue property of FV520B-I has ever been proposed. In this paper, both ultrasonic experiment and conventional experiment are conducted out to obtain the fatigue data. The effect of loading frequency on the fatigue data distribution is discussed firstly, its fatigue limit declines with the increase of the loading frequency. Then the fracture surface observations are captured, the fatigue property and fatigue behavior mechanism of FV520B-I is examined by analyzing the fracture surface features, crack initiation and failure observations. A new material frequency correction factor is proposed and introduced to eliminate the influence of the loading frequency on the FV520B-I fatigue property. FV520B-I empirical fatigue life conversion model and fatigue strength conversion model are established with comprehensive use of a fitting algorithm based on the combination of experimental data and classic formula. A clear understand of the effect of loading frequency on the fatigue property of FV520B-I is novel and has an important significance in guaranteeing the accuracy of the actual fatigue analysis of FV520B-I in the remanufacturing engineering.

4

Design of wireless power supply optimized structure for capsule endoscopes

Cui Ch., Zhao Q., Li Z.

Journal of Power Technologies

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2016

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Vol. 96, nr 2

101--109

EN

Wireless power transmission is an important method for powering wireless capsule endoscopes, but its efficiency is low, especially when the devices move freely in random positions and orientations. To improve the stability and efficiency of the endoscope in vivo, this study designed an optimization method for planar spiral coils utilized in wireless power transfer for capsule endoscopes. An optimized structure using six planar spiral coils was first proposed as the transmitting coil, and the efficiency of a series-parallel wireless power transmission model was analyzed. A theoretical model was then examined for the magnetic field vector distributions of the spiral-type transmitting coil by using an elliptic coordinate system. The relationship between the position of the receiving coil and the coupling coefficient was determined when the position and attitude changed. Finally, the experimental device of the wireless power supply system of the endoscope was designed with a class-E amplifier and Liz coil. The simulation and experimental results showed that the proposed method can generate high intensity magnetic field uniform, which can improve the efficiency of the wireless power transmission in the case of axial deviation and angular misalignment. The experimental results also indicated that the proposed scheme can meet the needs of the power supply of wireless endoscopes.

5

Composite Barycentric Rational Interpolation with High-Accuracy

Zhao Q., Liu X.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

214--216

EN

Rational interpolation gives much better approximations than polynomial interpolation, but it is difficult to avoid poles, unattainable points and control the occurrence of poles. In [1], a family of barycentric rational interpolants that have no poles and high approximation orders is given based on composite algorithm for the barycentric rational interpolation. In this paper, we propose a new composite barycentric rational interpolants with high-accuracy. The error estimation is discussed and a numerical example is given to show the effectiveness of our new method.

PL

W artykule przedstawiono nowy, złożony i wymierny interpolator barycentryczny o wysokiej dokładności. W klasycznej formie interpolacja wymierna ma znacznie lepsze własności aproksymacji niż interpolacji wielomianowa, lecz trudno w niej jest uniknąć biegunów, punktów nieosiągalnych i sterować ich występowaniem.

6

A New Routing Algorithm for Multi-path Transmission

Zhao A., Zhao Q.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

211--213

EN

A new multi-path routing algorithm called MA* algorithm is proposed which combines the path similarity objective with the heuristic method. A new evaluation function construction method is devised for the MA* algorithm, which is proved feasible through theoretical analysis. The simulation experiments are carried out to compare the MA* algorithm with other multi-path routing algorithms applying the network topology generation tool. The results show that the MA* algorithm can find multiple paths with reasonable path cost and path similarity at quite low search times.

PL

W artykule zaproponowano algorytm MA*, do routowania wielościeżkowego, uwzględniający założenie podobieństwa ścieżek i metodykę heurystyczną. Opracowano nową metodę oceny budowy dla algorytmu MA*, której wykonalność została udowodniona teoretycznie. Badania dowodzą, że algorytm MA* w krótkim czasie potrafi wyszukać ścieżki mnogie o uzasadnionych kosztach ścieżek i podobieństwie.

7

Experimental study on electrokinetic of kaolinite particles in aqueous suspensions

Min F., Zhao Q., Liu L.

Physicochemical Problems of Mineral Processing

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2013

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Vol. 49, iss. 2

659--672

EN

Influence of aqueous phase properties and process parameters on kaolinite particle zeta potential was quantified by electrophoresis experiments. The results indicated that pH strongly altered the zeta potential of kaolinite and it decreases at the beginning and then increases in the range of pH = 2–13. The activity of different cations changes the zeta potential and has the following tendency of Al3+ > Ca2+ > Mg2+ > Na+ and the zeta potential increases due to heterocoagulation of different mineral particles in suspension. It was found that the zeta potential of kaolinite particles increases after the suspension was stirred and decreases at the beginning, and then increases with soaking time. The FTIR results showed that the zeta potential takes into account ion adsorption and the change of Si–O, Al–O and Al–OH groups on the surface of the kaolinite particles.

8

Spectral degrees of cross-polarization of stochastic anisotropic electromagnetic beams in modified non-Kolmogorov atmospheric turbulence

Chen F., Chen J., Zhao Q., Chen Y, Xin Y., Li J., Pan H.

Optica Applicata

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2013

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Vol. 43, nr 4

773--783

EN

Based on the extended Huygens–Fresnel principle, variations in generalized Stokes parameters of stochastic anisotropic electromagnetic beams propagating through modified non-Kolmogorov atmospheric turbulence have been analyzed. The changes in generalized Stokes parameters with different turbulence parameters and source parameters were analyzed first. After that, the distributions of the spectral degrees of cross-polarization (SDCP) of isotropic beams and anisotropic beams were simulated. The results show that the profiles of distribution of SDCP of these two kinds of beams are very different in the near field, and will fluctuate through the propagation in atmospheric turbulence, but at last, when the propagation distance is long enough, the difference in the source makes a slight difference in the final profiles of SDCP in the output plane. They mainly depended on the turbulence perturbation, and in the weak turbulence, the profiles of final distribution show more flatter features.

9

Generalized Stokes parameters of random electromagnetic quasi-homogeneous beams on propagation

Chen J, Xin Y, Chen Y, Chen F, Zhao Q

Optica Applicata

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2013

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Vol. 43, nr 2

s. 205--216

EN

The expressions for the elements of the on-axis and transverse generalized Stokes parameters of random electromagnetic quasi-homogeneous beams on propagation are presented and are used to study the polarization properties of the beams. Some typical numerical calculations of the on-axis and transverse Stokes parameters, polarization properties of the beams on propagation are illustrated. The results show that for different sources all the on-axis parameters are identical in the near field and keep fixed values in the far field. But the transverse parameters are affected greatly by the properties of the source even in the near field. We have also found that the spatial profiles of the transverse parameters remain unchanged upon propagation.

10

Fixed final time optimal adaptive control of linear discrete-time systems in input-output form

Zhao Q., Xu H., Jagannathan S.

Journal of Artificial Intelligence and Soft Computing Research

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2013

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Vol. 3, No. 3

175--187

EN

In this paper, the fixed final time adaptive optimal regulation of discrete-time linear systems with unknown system dynamics is addressed. First, by transforming the linear systems into the input/output form, the adaptive optimal control design depends only on the measured outputs and past inputs instead of state measurements. Next, due to the time-varying nature of finite-horizon, a novel online adaptive estimator is proposed by utilizing an online approximator to relax the requirement on the system dynamics. An additional error term corresponding to the terminal constraint is defined and minimized overtime. No policy/value iteration is performed by the novel parameter update law which is updated once a sampling interval. The proposed control design yields an online and forward-in-time solution which enjoys great practical advantages. Stability of the system is demonstrated by Lyapunov analysis while simulation results verify the effectiveness of the propose approach.

11

Degrees of cross-polarization of a partially coherent electromagnetic beam in uniaxial crystals

Li J., Chen Y., Zhao Q., Zhou M.

Optica Applicata

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2010

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Vol. 40, nr 1

93--100

EN

Propagation of degrees of cross-polarization of a partially coherent electromagnetic beam in uniaxial crystals orthogonal to the optical axis is investigated. Based on the paraxial theory of beams, analytical propagation formulas for degrees of cross-polarization are derived and analyses are illustrated by numerical examples. It is found that values of the degree of cross-polarization in uniaxial crystals fluctuate more rapidly with larger deviation of correlation length parameters (?ij - ?ii), but show slight variation with larger ratio of refractive index (ne/n0) or incident beam wavelength. Results also show that sources with sufficient correlation length parameters generate invariable degree of cross-polarization in uniaxial crystals.

12

Converter end-point prediction model using spectrum image analysis and improved neural network algorithm

Wen H. Y., Zhao Q., Chen Y. R., Zhou M. C., Zhang M., Xu L. F.

Optica Applicata

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2008

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Vol. 38, nr 4

693-704

EN

Aiming at the present situation of the steelmaking end-point control at home and abroad, a neural network model was established to judge the end-point. Based on the colour space conversion and the fiber spectrum division multiplexing technology, a converter radiation multi-frequency information acquisition system was designed to analyze the spectrum light and image characteristic information, and the results indicate that they are similar at early-middle stage but dissimilar when approach the steelmaking blowing end. The model was trained and forecasted by using an improved neural network correction coefficient algorithm and some appropriate variables as the model parameters. The experimental results show the proposed algorithm improves the prediction accuracy by 15.4% over the conventional algorithm in 5s errors and the respond time is about 1.688s, which meets the requirements of end-point judgment online.

13

Synthesis and Characterization of a Novel Complex [Cd(2,2'-Py2S)Cl2] with 2,2'-Py2S = 2,2'-Thiobispyridine

Zhao Q., Mu X., Fang R.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 7

1369-1373

14

Reliability modeling of fault tolerant control systems

Li H., Zhao Q., Yang Z.

International Journal of Applied Mathematics and Computer Science

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2007

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Vol. 17, no 4

491-504

EN

This paper proposes a novel approach to reliability evaluation for active Fault Tolerant Control Systems (FTCSs). By introducing a reliability index based on the control performance and hard deadline, a semi-Markov process model is proposed to describe system operation for reliability evaluation. The degraded performance of FTCSs in the presence of imperfect Fault Detection and Isolation (FDI) is reflected by semi-Markov states. The semi-Markov kernel, the key parameter of the process, is determined by four probabilistic parameters based on the Markovian model of FTCSs. Computed from the transition probabilities of the semi-Markov process, the reliability index incorporates control objectives, hard deadline, and the effects of imperfect FDI, a suitable quantitative measure of the overall performance.

15

Dihydroisocoumarins from the Fungus Cephalosporium sp. AL031

Bi Y., Bi X., Zhao Q., Fang A, Chen Y.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 3

397-401

EN

Three novel dihydroisocoumarins, (2E)-3-[(3S)-5-acetyl-3,4-dihydro-6-methoxy-1- oxo-1H-2-benzopyran-3-yl]-2-propenoic acid (1), (3S)-5-hydroxymellein (3) and (3S)-7-hydroxymellein (4) were isolated from the ethyl acetate extract of a culture broth of a strain of the fungus Cephalosporium sp. AL031, together with one known compound (3S)-mellein (2). Their structures were characterized by spectroscopic analysis and comparison of their spectral data with reported values.

16

Speeding-up normalized neural networks for face/object detection

El-Bakry H. M., Zhao Q.

Machine Graphics and Vision

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2005

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Vol. 14, No. 1

29-59

EN

Finding an object or a face in an input image is a search problem in the spatial domain. Neural networks have shown good results in detecting a certain face/object in a given image. In this paper, faster neural networks for face/object detection are presented. Such networks are designed based on cross correlation in the frequency domain between the input image and the input weights of neural networks. This approach is developed to reduce the computation steps required by these faster neural networks for the search process. The principles of divide and conquer strategy is applied through image decomposition. Each images is divided into small-size sub- images, and then each of them is tested separately using a single faster neural network. Furthermore, the fasted face/object detection is achieved using parallel processing techniques to test the resulting sub-images simultaneously using the same number of faster neural networks. In contrast to using faster neural networks only, the speed-up ratio is increased with the size of the input image when using faster neural networks and image decomposition. Moreover, the problem of local subimage normalization in the frequency domains is solved. The effect of image normalization on the speed-up ratio for face/object detections discussed. Simulation results show that local subimage normalization through weight normalization is faster than subimage normalization in the spatial domain. The overall speed- up ratio of the detection process is increased as the normalization of weights is carried out off line.

17

Synthesis, Crystal Structure and Magnetic Properties of [Mn(L)2(N(CN)2)2], a One-Dimensional Systems with End to End Single Dicyanamide Bridges (L=4-Cyanopyridine N-Oxide)

Zhao Q., Liu Y. Q., Fang R.

Polish Journal of Chemistry

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2004

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Vol. 78 / nr 3

343-348

EN

Anew 1-D polymeric coordination compound [Mn(L)2(N(CN)2)2] (L = 4-cyanopyridine N-oxide) has been synthesized and characterized. The crystal structure of this compound was determined by X-ray diffraction analysis. In the crystal structure, the [Mn(L)2]2+ units are linked by [N(CN)2]- _-bridging ligands to form one dimensional structure. The manganese ions display four coordination, with two terminal N atoms of different [N(CN)2]- ligands and twoOatoms of different 4-cyanopyridine N-oxide ligands. Analysis of variable temperature magnetic susceptibility (2-300 K) indicates that the polymer shows weak antiferromagnetic interaction.

18

Synthesis, Crystal Structure and Magnetic Properties of a Zinc(II) Complex with Nitronyl Nitroxide Radical

Zhao Q., Wang X. -F., Tang D. -Y., Fang R. -B.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 10

1229-1234

EN

Anew mononuclear diamagnetic metal zinc compound [Zn(NITpPy)4(N3)2] (NITpPy = 2-(p-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been synthesized and characterized. The crystal structure of this compound was determined by X-ray diffraction analysis. It crystallizes in the triclinic space group PI with the ZnII ion octahedrally coordinated and bound to four radical ligands through the nitrogen atoms of the pyridine rings, and the azido groups occupy the apical positions. The compound exhibits weak intermolecular antiferromagnetic interaction between the radicals, in which the diamagnetic zinc(II) plays the role of bridge.

19

Syntheses and Crystal Structures of Zinc(II) Complexes with Two Kinds of Benzoate Derivatives

Zhao Q., Li H.-F., Ma Y. -P., Fang R. -B.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 4

497-502

EN

Two novel zinc(II) complexes of [Zn(L1)2(phen)]_5H2O 1 (L1 = 4-aminobenzoic acid, phen = 1,10-phenanthroline) and [Zn(L2)2(en)] 2 (L2 = 4-methoxybenzoic acid, en = ethylenediamine) have been prepared and characterized by X-ray single crystal structural analysis. Complex 1 crystallizes in the tetragonal system, space group I41/a. The zinc atom of the central ZnO3N2 system is pentahedral coordinated by two N atoms of phen and three O atoms of 4-aminobenzoic acid. Complex 2 belongs to orthorhombic system, space group Pbcn. The zinc atom of the central ZnO2N2 system lies on a twofold symmetry axis and is tetrahedrally coordinated by two N atoms of en and two O atoms of 4-methoxybenzoic acid.