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1

A hierarchical inferential method for indoor scene classification

Jiang J., Liu P., Ye Z., Zhao W., Tang X.

International Journal of Applied Mathematics and Computer Science

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2017

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Vol. 27, no. 4

839--852

EN

Indoor scene classification forms a basis for scene interaction for service robots. The task is challenging because the layout and decoration of a scene vary considerably. Previous studies on knowledge-based methods commonly ignore the importance of visual attributes when constructing the knowledge base. These shortcomings restrict the performance of classification. The structure of a semantic hierarchy was proposed to describe similarities of different parts of scenes in a fine-grained way. Besides the commonly used semantic features, visual attributes were also introduced to construct the knowledge base. Inspired by the processes of human cognition and the characteristics of indoor scenes, we proposed an inferential framework based on the Markov logic network. The framework is evaluated on a popular indoor scene dataset, and the experimental results demonstrate its effectiveness.

2

Adaptive robust simultaneous stabilization controller with tuning parameters design for two dissipative Hamiltonian systems

Cao Z., Hou X., Zhao W.

Archives of Control Sciences

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2017

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Vol. 27, no. 4

505--525

EN

This paper investigates the problem of adaptive robust simultaneous stabilization (ARSS) of two dissipative Hamiltonian systems (DHSs), and proposes a number of results on the controller parameterization design. Firstly, an adaptive H∞ control design approach is presented by using the dissipative Hamiltonian structural for the case that there are both external disturbances and parametric uncertainties in two DHSs. Secondly, an algorithm for solving tuning parameters of the controller is proposed using symbolic computation. The proposed controller parameterization method avoids solving Hamilton-Jacobi-Issacs (HJI) equations and the obtained controller is easier as compared to some existing ones. Finally, an illustrative example is presented to show that the ARSS controller obtained in this paper works very well.

3

2D Structural Acoustic Analysis Using the FEM/FMBEM with Different Coupled Element Types

Chen L., Zhao W., Liu C., Chen H.

Archives of Acoustics

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2017

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Vol. 42, No. 1

37--48

EN

A FEM-BEM coupling approach is used for acoustic fluid-structure interaction analysis. The FEM is used to model the structure and the BEM is used to model the exterior acoustic domain. The aim of this work is to improve the computational efficiency and accuracy of the conventional FEM-BEM coupling approach. The fast multipole method (FMM) is applied to accelerating the matrix-vector products in BEM. The Burton-Miller formulation is used to overcome the fictitious eigen-frequency problem when using a single Helmholtz boundary integral equation for exterior acoustic problems. The continuous higher order boundary elements and discontinuous higher order boundary elements for 2D problem are developed in this work to achieve higher accuracy in the coupling analysis. The performance for coupled element types is compared via a simple example with analytical solution, and the optimal element type is obtained. Numerical examples are presented to show the relative errors of different coupled element types.

4

Numerical test on polystyrene tunnel seismic-isolation material

He J., Chen W., Zhao W., Huang S., Yao Y.

Polish Journal of Chemical Technology

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2016

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Vol. 18, nr 3

122--127

EN

Stress-strain mechanical properties of polystyrene foam plastic material were tested under different loading conditions. An empirical constitutive model for describing metal materials was proposed for the polystyrene plastic foam. The static and dynamic tests results show that the ductility and watertightness of the polystyrene plastic foam are significantly improved. At the same time, in order to check its seismic-isolation property, the high-performance foam concrete as filling materials of Galongla tunnel in Tibet was simulated by FEM. The simulated results show that the polystyrene plastic foam can remarkably decrease the stress and the plastic zone in final lining, so it can effectively reduce the seismic damage of the tunnel. Considering the seismic-isolation property and low price of polystyrene plastic foam, it is a good reference for the anti-seismic design of tunnels in high intensity zones.

5

Effect of pH on surface characteristics and flotation of sulfidized cerussite

Feng Q., Wen S., Zhao W., Liu J., Liu D.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 2

676--689

EN

The effect of pH on surface characteristic and flotation of sulfidized cerussite was studied by micro-flotation tests, dissolution experiments, scanning electron microscopy (SEM) energy dispersive spectrometer (EDS), and X-ray photoelectron spectroscopy (XPS). The micro-flotation tests demonstrated that higher recovery of cerussite was achieved in acidic solutions than that in alkaline solutions. Despite the addition of high collector concentrations, cerussite flotation did not improved in alkaline solutions. The dissolution performance of sulfide-treated cerussite at different pH values indicated that the lead sulfide layer on the surface of sulfide-treated cerussite could exist in acidic solutions and it was more stable at acidic pH than in alkaline solutions. This finding was proved by the SEM-EDS and XPS analyses.

6

Surface-based Internal Multiple Elimination in the CMP Domain − Theory and Application Strategies on Land Seismic Data

Deng S., Zhao W., Liu Z.

Acta Geophysica

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2016

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Vol. 64, no. 6

2114--2135

EN

The data-driven internal multiple elimination (IME) method based on feedback model, which includes CFP-based, surface-based and inversion-based methods, are successfully applied to marine datasets. However, these methods are computationally expensive and not always straightforward on land datasets. In this paper, we first proved that the surface-based IME method, which is the most computationally efficient method among the three methods, can be derived from the CFP theory. Then we extend it to CMP domain under the assumption of locally lateral invariance of the earth, which makes it more computationally efficient. In addition, we proposed applying a time-variant taper based on the first Fresnel zone to predict the multiples more percisely. Besides, the improved S/N ratio and dense offset distribution can be obtained by using the CMP supergather, which makes the CMP-oriented method more suitable for land data. Some practical processing strategies are proposed via case study. The effectiveness of the proposed method is demonstrated with the application to synthetic and field data.

7

Investigation of leaching kinetics of cerussite in sodium hydroxide solutions

Feng Q., Wen S., Wang Y., Zhao W., Deng J.

Physicochemical Problems of Mineral Processing

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2015

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Vol. 51, iss. 2

491--500

EN

The leaching kinetics of cerussite in alkaline medium was investigated with respect to experimental variables such as sodium hydroxide concentration, temperature, particle size and stirring speed. The results showed that leaching reagent concentration and reaction temperature exerted significant effects on the extraction of lead, whereas particle size and stirring speed exhibited a relatively moderate effect on the leaching rate. The leaching process followed the kinetic law of the shrinking core model, and the dissolution rates were controlled by the surface chemical reaction with an apparent activation energy value of 43.79 kJ/mol. A corresponding dissolution kinetic equation was also proposed to describe the dissolution reaction. The results indicated that sodium hydroxide could be used as an effective leaching reagent for extracting lead from cerussite.

8

Effects Of Anodic Protection On SCC Behavior Of X80 Pipeline Steel In High-pH Carbonate-Bicarbonate Solution

Zhao W., Zou Y., Xia D. X., Zou Z. D.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 2A

1009--1013

EN

The potentiodynamic polarization test and slow strain rate tensile tests of X80 pipeline steel were performed in 0.5M Na2CO3-1M NaHCO3 solution to study the electrochemical and stress corrosion cracking properties. The results of potentiodynamic polarization test show that there is an obvious stable passive region, about from 0v to 0.8V (SCE), indicating that anodic protection is feasible. The results of slow strain rate tensile tests show that the stress corrosion cracking sensibility is high and cathodic protection effect is restricted due to the hydrogen permeation. However, the elongation, yielding strength and tensile strength all increase with anodic protection. The higher anodic protection potential in the stable passive region is benefit to improve tensile strength and yielding strength. However, the higher elongation is obtained at 0.5V (SCE) anodic protection potential.

PL

Badania polaryzacji potencjodyniamicznej oraz próby powolnego rozciągania (SSRT) przeprowadzono na stali typu X80 w roztworze 0,5M Na2CO3-1M NaHCO3. Określono odporność na korozję elektrochemiczną oraz zbadano zjawisko naprężeniowego pękania korozyjnego. Rezultaty badań polaryzacji potencjodynamicznej wykazały istnienie stabilnego obszaru pasywacji w zakresie potencjału od 0V do 0,8V (SCE: półogniwo odniesienia – elektroda kalomelowa). Próby powolnego rozciągania pokazały wysoką wrażliwość materiału na naprężeniowe pękanie korozyjne i ograniczenia ochrony katodowej w związku z przenikaniem wodoru. Ochrona anodowa natomiast, zwiększa znacząco wydłużenie próbki, granicę plastyczności oraz wytrzymałość na rozciąganie. Ponadto zwiększanie wartości potencjału w stabilnym obszarze pasywacji dodatkowo poprawia te właściwości.

9

Realtime motion assessment for rehabilitation exercises: integration of kinematic modeling with fuzzy inference

Zhao W., Lun R., Espy D. D., Reinthal M. A.

Journal of Artificial Intelligence and Soft Computing Research

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2014

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Vol. 4, No. 4

267--285

EN

This article describes a novel approach to realtime motion assessment for rehabilitation exercises based on the integration of comprehensive kinematic modeling with fuzzy inference. To facilitate the assessment of all important aspects of a rehabilitation exercise, a kinematic model is developed to capture the essential requirements for static poses, dynamic movements, as well as the invariance that must be observed during an exercise. The kinematic model is expressed in terms of a set of kinematic rules. During the actual execution of a rehabilitation exercise, the similarity between the measured motion data and the model is computed in terms of their distances, which are then used as inputs to a fuzzy interference system to derive the overall quality of the execution. The integrated approach provides both a detailed categorical assessment of the overall execution of the exercise and the degree of adherence to individual kinematic rules.

10

Flotation kinetics and separation selectivity of coal size fractions

Li Y., Zhao W., Gui X., Zhang X.

Physicochemical Problems of Mineral Processing

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2013

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Vol. 49, iss. 2

387--395

EN

Flotation recovery and kinetics for three size fractions of coal were investigated. Flotation of combustible matter recovery was approximated with the first order kinetic equation while flotation of the ash forming minerals with the second order equation. Next, the equations for each size fraction were combined and a formula was obtained which was used for approximation of the experimental results using the so-called Fuerstenau upgrading curve, which relates the recovery of combustible matter recovery and recovery of ash forming minerals, both in concentrate. The Fuerstenau upgrading plot showed that the best selectivity was obtained for the middle size fraction of 0.25–0.075 mm, while the flotation selectivity of larger 0.5–0.25 mm and smaller –0.075 mm particles was diminished. This finding agrees with many other investigations.

11

Preparation, characterization and photocatalytic performances of materials based on CS2-modified titanate nanotubes

An H., Hu X., Zhu B., Song J., Zhao W., Zhang S., Huan W.

Materials Science Poland

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2013

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Vol. 31, No. 4

531--542

EN

CS2-modified titanate nanotubes (CS2/TiO2–NTs) are fabricated by reaction of CS2 and Ti–O2Na+ species on titanate nanotubes. Pb2+ ions are coated on the modified nanotubes by ion exchange (Pb/CS2/TiO2–NTs). The products are characterized by means of nitrogen adsorption-desorption isotherms at 77 K (BET method), transmission electron microscopy (TEM), X-ray photoelectron spectrometry (XPS), X-ray diffraction (XRD), atomic absorption spectrometry (AAS), and diffuse reflectance spectroscopy (DRS). The photocatalytic performances of the products are evaluated by monitoring their catalytic activities for degradation of methyl orange under UV light irradiation. The effects of calcination temperature and atmosphere on the photocatalytic performance are investigated. The results reveal that the photocatalytic activities of CS2/TiO2–NTs and Pb/CS2/TiO2–NTs are far higher than that of primary nanotubes, and the optimum calcination temperature is 500 °C under N2 atmosphere. It is also discovered that physically adsorbed Pb2+ ions affect the photocatalytic activity of Pb/CS2/TiO2–NTs obviously. The photocatalytic activity of washed Pb/CS2/TiO2–NTs is higher than that of the unwashed one under the same thermal treatment and reaction conditions.

12

Energy conserving based k-coverage algorithm for dense wireless sensor networks

Liu Z., Zhao W., Wang J., Zhang M.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 1b

74-77

EN

As the energy supply of wireless sensor is limited, it is important to dynamically configure wireless sensor networks by correctly setting the on/off status of each sensor to let every target be k covered. In this paper, we propose an energy-efficient distributed target k-coverage algorithm for dense heterogeneous wireless sensor networks with multiple sensing units. To save the energy of sensors more efficiently, the sensing ability and the remaining energy of a given sensor is integrated to calculate sensor priority. The proposed approach is locally and simultaneously running at each sensor in a rounding mode. Each sensor should decide the on/off status of its sensing units at the beginning of each round, and then transmits this decision to its one-hop neighbours. The higher the priority of a sensor is, the shorter the decision time it needs. Experimental results show that compared with Energy First scheme and Integer Linear Programming solution, our approach has longer network lifetime than Energy First scheme, and the performance of our approach is second only to Integer Linear Programming solution.

PL

W artykule zaproponowano energooszczędny algorytm dla gęstej, niejednorodnej sieci bezprzewodowej czujników. Każdy czujnik decyduje o stanie włączenia lub wyłączenia na początku każdej rundy testowania a następnie przeprowadzana jest transmisja danych do sąsiada. W zależności od priorytetu czujnika czas decyzji jest krótszy.

13

Load-bearing evaluation of spinal posterior column by measuring surface strain from lumbar pedicles. An in vitro study

Sun P., Zhao W., Bi Z., Wu Ch., Ouyang J.

Acta of Bioengineering and Biomechanics

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2012

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Vol. 14, no. 1

45-49

EN

An understanding of the load transfer within spinal posterior column of lumbar spine is necessary to determine the influence of mechanical factors on potential mechanisms of the motion-sparing implant such as artificial intervertebral disc and the dynamic spine stabilization systems. In this study, a new method has been developed for evaluating the load bearing of spinal posterior column by the surface strain of spinal pedicle response to the loading of spinal segment. Six cadaveric lumbar spine segments were biomechanically evaluated between levels L1 and L5 in intact condition and the strain gauges were pasted to an inferior surface of L2 pedicles. Multidirectional flexibility testing used the Panjabi testing protocol; pure moments for the intact condition with overall spinal motion and unconstrained intact moments of +-8 Nm were used for flexion-extension and lateral bending testing. High correlation coefficient (0.967-0.998) indicated a good agreement between the load of spinal segment and the surface strain of pedicle in all loading directions. Principal compressive strain could be observed in flexion direction and tensile strain in extension direction, respectively. In conclusion, the new method seems to be effective for evaluating posterior spinal column loads using pedicles' surface strain data collected during biomechanical testing of spine segments.