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1

Ship recognition and tracking system for intelligent ship based on deep learning framework

Liu B., Wang S. Z., Xie Z. X., Zhao J. S., Li M. F.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2019

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Vol. 13. no. 4

699--705

EN

Automatically recognizing and tracking dynamic targets on the sea is an important task for intelligent navigation, which is the prerequisite and foundation of the realization of autonomous ships. Nowadays, the radar is a typical perception system which is used to detect targets, but the radar echo cannot depict the target’s shape and appearance, which affects the decision-making ability of the ship collision avoidance. Therefore, visual perception system based on camera video is very useful for further supporting the autonomous ship navigational system. However, ship’s recognition and tracking has been a challenge task in the navigational application field due to the long distance detection and the ship itself motion. An effective and stable approach is required to resolve this problem. In this paper, a novel ship recognition and tracking system is proposed by using the deep learning framework. In this framework, the deep residual network and cross-layer jump connection policy are employed to extract the advanced ship features which help enhance the classification accuracy, thus improves the performance of the object recognition. Experimentally, the superiority of the proposed ship recognition and tracking system was confirmed by comparing it with state of-the-art algorithms on a large number of ship video datasets.

2

Simultaneous extraction of vanadium and chromium from vanadium slag using low-pressure liquid phase oxidation method

Xia J.-P., Zheng S.-L., Wang S.-N., Liu B., Zou X.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 2

609--619

EN

A low-pressure liquid oxidation method was proposed and proven to be effective to extract vanadium and chromium simultaneously from the vanadium slag in concentrated NaOH aqueous solutions. The effect of temperature, NaOH mass concentration, liquid-to-solid mass ratio, stirring speed and pressure on the extraction of vanadium and chromium in NaOH aqueous solutions were systematically investigated. Under the optimal reaction conditions (temperature of 473 K, liquid-to-solid mass ratio of 6:1, stirring speed of 700 rpm, NaOH mass concentration of 50%, pressure of 1 MPa and reaction time of 180 min), the vanadium and chromium recovery reached 95% and 90%, respectively. It was found that the reaction temperature and NaOH concentration were important factors for the extraction of vanadium and chromium. The kinetics of the decomposition of vanadium slag in concentrated NaOH aqueous under low pressure was analyzed using the shrinking core model, and the results indicated that the extraction of vanadium and chromium were both governed by the internal diffusion step, with apparent activation energies calculated to be 26.22 and 32.79 kJ/mol, respectively.

3

A novel method to extract vanadium from high-grade vanadium slag: non-salt roasting and alkaline leaching

Liu B., Meng L., Zheng S., Li M., Wang S.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 3

657--667

EN

A new method using non-salt roasting-alkaline leaching to treat vanadium slag was proposed in this study. The V(III) in vanadium slag is oxidized to V(V) by roasting and the latter can be effectively leached out as vanadate by alkaline leaching. This method possesses distinct advantage of being able to treat high-grade vanadium slag. For the South Africa high-grade vanadium slag, the maximum vanadium recovery of 98% was achieved when the reaction conditions were roasting temperature of 850 °C, roasting time of 2 h, alkali concentration of 30 wt.%, leaching temperature of 210 °C, and leaching time of 2 h. The roasting and leaching mechanisms have been well elucidated based on the XRD and SEM analysis results. The phases transitions of vanadium slag were clearly presented. This work has laid the foundation for the industrial application of non-salt roasting-alkaline leaching and provided new insights into effective extraction of high-grade vanadium slag.

4

Optimising extended warranty policies following the two-dimensional warranty with repair time threshold

Wang L., Pei Z., Zhu H., Liu B.

Eksploatacja i Niezawodność

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2018

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Vol. 20, no. 4

523--530

EN

This paper considers an optimal extended warranty policies after the expiration of base two-dimensional warranty with repair time threshold. During the base two-dimensional warranty period, each failure of the equipment can be either replaced or minimally repaired depending on a pre-specified repair time threshold. After the base warranty expires, the length of an extended warranty policy is available for selection. The equipment is minimally repaired on each failure during the extended warranty. In this study, the length of the extended warranty period is optimized by minimizing the expected cost rate incurred over the whole warranty coverage, from the views of customs and manufacturers respectively. For the purpose of illustration, we present and discuss some numerical examples. The effect of repair time threshold on the optimal strategy is also investigated numerically.

PL

W niniejszej pracy rozważano optymalną politykę przedłużania gwarancji po wygaśnięciu podstawowej gwarancji dwuwymiarowej z ustaloną górną granicą czasu naprawy. W podstawowym okresie obowiązywania gwarancji dwuwymiarowej, po każdej awarii urządzenie zostaje poddane minimalnej naprawie, lub – jeśli naprawa nie może być wykonana we wcześniej ustalonym czasie naprawy – wymienione. Po wygaśnięciu gwarancji podstawowej, konieczne jest wybranie długości okresu obowiązywania gwarancji rozszerzonej. Podczas trwania okresu gwarancji przedłużonej, sprzęt naprawia się w sposób minimalny (naprawa minimalna) po każdorazowym uszkodzeniu. W niniejszej pracy, optymalizowano długość przedłużonego okresu gwarancyjnego poprzez minimalizację oczekiwanych kosztów poniesionych podczas całego okresu trwania gwarancji; optymalizację przeprowadzono z perspektywy klienta jak i producenta . Dla ilustracji, przedstawiono i omówiono wybrane przykłady numeryczne. Przeprowadzono także analizę numeryczną wpływu górnej granicy czasu naprawy na optymalną strategię gwarancyjną.

5

Thermoelectric properties of Ni0.15Co3.85Sb12 and Fe0.2Ni0.15Co3.65Sb12 skutterudites prepared by HPHT method

Kong L., Ma H., Zhang Y., Guo X., Sun B., Liu B., Liu H., Liu B., Chen J., Jia X.

Materials Science Poland

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2017

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Vol. 35, No. 3

496--500

EN

N-type polycrystalline skutterudite compounds Ni0.15Co3.85Sb12 and Fe0.2Ni0.15Co3.65Sb12 with the bcc crystal structure were synthesized by high pressure and high temperature (HPHT) method. The synthesis time was sharply reduced to approximately half an hour. Typical microstructures connected with lattice deformations and dislocations were incorporated in the samples of Ni0.15Co3.85Sb12 and Fe0.2Ni0.15Co3.65Sb12 after HPHT. Electrical and thermal transport properties were meticulously researched in the temperature range of 300 K to 700 K. The Fe0.2Ni0.15Co3.65Sb12 sample shows a lower thermal conductivity than that of Ni0.15Co3.85Sb12. The dimensionless thermoelectric figure-of-merit (zT) reaches the maximal values of 0.52 and 0.35 at 600 K and 700 K respectively, for Ni0.15Co3.85Sb12 and Fe0.2Ni0.15Co3.65Sb12 samples synthesized at 1 GPa.

6

Double-layer microwave absorber based on nanocrystalline CoFe2O4 and CoFe2O4/PANI multi-core/shell composites

Xu Y., Shen G., Wu H., Liu B., Fang X., Zhang D., Zhu J.

Materials Science Poland

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2017

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Vol. 35, No. 1

94--104

EN

Organic-inorganic nano-CoFe2O4/PANI (polyaniline) multi-core/shell composites have been successfully synthesized by chemical oxidative polymerization of aniline. The characterization results showed that the ferrite nanocrystals were efficiently embedded in PANI. The electromagnetic parameters of the composites were measured by a vector network analyser in the frequency range of 2 GHz to 18 GHz. Double-layer absorbers based on the CoFe2O4/PANI composite (matching layer) and calcined CoFe2O4 ferrite (absorbing layer) have been designed. The reflection loss of the microwave absorbers of both single layer and double-layer with a total thickness of 2.0 mm and 2.5 mm was calculated according to transmission-line theory. The results indicated that the minimum reflection loss of the CoFe2O4/PANI composite was −19.0 dB at 16.2 GHz at the thickness of 2.0 mm and −23.6 dB at 13.1 GHz at the thickness of 2.5 mm, respectively. The minimum reflection loss for double-layer absorbers reached −28.8 dB at 16.2 GHz at the total thickness of 2.0 mm, and −31.1 dB at 12.8 GHz at the total thickness of 2.5 mm. The absorption bandwidth under −10 dB was 4.2 GHz (13.8 GHz to 18.0 GHz) and 5.5 GHz (10.3 GHz to 15.8 GHz), respectively. The results show that the reflection loss and absorption bandwidth of the double-layer absorbers are obviously enhanced compared to corresponding single layer absorbers.

7

Texture Analysis Method Based on Fractional Fourier Entropy and Fitness-scaling Adaptive Genetic Algorithm for Detecting Left-sided and Right-sided Sensorineural Hearing Loss

Wang S., Yang M., Li J., Wu X., Wang H., Liu B., Dong Z., Zhang Y.

Fundamenta Informaticae

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2017

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Vol. 151, nr 1/4

505--521

EN

To detect the sensorineural hearing loss (SNHL) from healthy people accurately, we used magnetic resonance imaging (MRI) to obtain the imaging data, and then proposed a new computer-aided diagnosis (CAD) system, on the basis of texture analysis method. In the first, we extracted 12-element feature from each brain image via fractional Fourier entropy (FRFE). Afterwards, multilayer perceptron (MLP) was employed as the classifier, which was trained by a novel fitness-scaling adaptive genetic algorithm (FSAGA). The statistical analysis over 49 subjects showed the overall accuracy of our method yielded 95.51%. Experimental results performed better than four state-of-the-art weight optimization methods, and this CAD system give significantly better performance than manual interpretation.

8

Analysing effective thermal conductivity of 2D closed-cell foam based on shrunk Voronoi tessellations

Wang H., Liu B., Kang Y.-X., Qin Q.-H.

Archives of Mechanics

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2017

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Vol. 69, nr 6

451--470

EN

Two-dimensional foam is a type of cellular solid materials containing a high volume fraction of pores. The thermal behavior of foam depends strongly on its microscopic structure. In this study, a two-dimensional closed-cell foam model containing randomly distributed air voids and solid walls is designed via a Voronoi diagram enhanced by the shrinking technique to approximately represent the real foam structure. The porosity, pore size and solid wall thickness of the established random foam structure is examined by introducing the so-called shrinking ratio. Subsequently, the effective thermal conductivity of the rebuilt foam model is numerically presented through the finite element analysis. The numerical results obtained are verified by comparison with the available theoretical and experimental results. In the analysis, the effects of porosity, number of pores and thermal conductivity of solid phase in foam structures are investigated respectively to reveal the relationship of geometric parameters and thermal properties of solid phase with effective thermal conductivity of the foam.

9

Effects of Litter Accumulation on Plant Communities in Fenced Desert Steppe

Li X., Liu B., Chen L., Song N.

Polish Journal of Ecology

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2015

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Vol. 63, nr 3

333--340

EN

The litter decomposition plays an important role in nutrient circle of grassland ecosystem, the water holding ability of litter and physical and chemical characteristics have been studied exclusively over the past century. However, the effect of litter accumulation on plant community in desert steppe under fenced condition was little known. In this study, four typical plant communities were employed to identify the effects of litter accumulation on plant communities. The results showed the trend of litter accumulation amount in the four different types of plant communities was best represented by Birk model. The accumulation of litter had different effects on the number of seedlings. When litter accumulation reached 300–400 g cm-2, green-up dates advance 7 days. The amount of seedling germination and the number of plant species reached a peak. Meanwhile, plant density, coverage, average height, richness, and evenness reached maximum values. It was concluded that when opposite fencing time was about 6 years, and the optimum amount of litter accumulation was about 300–400 g cm-2, which could advance the green-up dates and increase the number of plant seedlings, and also improve or maintain community stability. Such a notion has to be taken into account for the development of an improved policy for environmental management in desert steppe.

10

Design and experiments using a spiral-liquid-solid fluidized bed system

Sha J., Liang L., Liu B., Xie G., Peng Y.

Physicochemical Problems of Mineral Processing

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2015

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Vol. 51, iss. 2

427--434

EN

Liquid-solid fluidized bed (LSFB) has been widely known and used for separation of coarse coal particles (normally larger than 0.25 mm). The process of separation by LSFB needs fluidization water from the bottom to the top of LSFB. The fluidization water is formed by the water addition at the bottom of the LSFB. Normally the quantity of water addition is very large, which increases the burden of water treatment in coal preparation processes. In this investigation, a spiral unit was introduced into the conventional LSFB and the new separation equipment was named S-LSFB. The spiral unit could provide an upward force for the upward movement of coarse low density coals into the concentrate, and hence the quantity of water addition for fluidization water may be reduced. Samples of 0.5-0.25 mm size fraction coal were used to investigate the difference in separation performance between S-LSFB and LSFB. It was found that the separation performance of S-LSFB was nearly equal to that of LSFB. S-LSFB may be beneficial to coarse coal separation in coal preparation plant since the burden of water treatment can be reduced by the application of S-LSFB.

11

Numerical study of stall inception in a transonic axial compressor rotor based on the throttle model

Zhu X., Liu B., Hu J., Shen X.

Journal of Theoretical and Applied Mechanics

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2015

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Vol. 53 nr 2

307--316

EN

The goal of the current paper is to investigate inner flow behavior on stall inception in a transonic compressor rotor. The stall inception process is numerically carried out by unsteady 3-D simulations based on the throttle model. The current study shows that stall starts from the tip of the blade, and stall cell extends to the axial, circumferential and radial directions. Through the comparison of flow transition characteristics at different flow rate conditions, the interface between the incoming flow and tip clearance flow shifts forward to the upstream as the mass flow decreases. Eventually, the shock detaches from the blade leading edge, and tip clearance flow spills into the adjacent blade passage, thus stall happens in the affected blade passages.

12

Sensorless Vector Control for Permanent Magnet Synchronous Motor based on Estimation of Model Error

Liu Z., Liu B.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 3b

15--17

EN

A method, which estimates the position of the rotor based on arithmetic model of the motor, is presented in this paper. In this method, mathematical mode of PMSM is regarded as reference model. By detecting the phase current of PMSM, the real position of the rotor of PMSM is calculated. And this method eliminates the parameters variation of the PMSM. Simulation and experimental results proved that the proposed method was capable of precisely estimating the rotor position and speed. It also achieved good static and dynamic speed. Also, the parameters are fixed according to this method, so the simulation model of the whole PMSM speed servo is more precise.

PL

W artykule przedstawiono metodę estymacji pozycji wirnika w maszynie PMSM. Algorytm opiera się na pomiarach prądów fazowych, na podstawie których dokonywana jest estymacja, eliminując w ten sposób parametry maszyny. Przedstawiono wyniki symulacyjne i eksperymentalne, potwierdzające skuteczność działania.

13

Research on Interval Concept Lattice and its Construction Algorithm

Liu B., Zhang C., Yang Y.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

1--6

EN

In classic concept lattice and rough concept lattice, the concept extents have all the attributes or only one attribute sometimes. So the support and confidence degree of the extracted association rules would be reduced greatly. To solve this problem, authors have put forward a new concept lattice structure: interval concept lattice Lαβ (Mα, Mβ,Y) based on the parameter interval [ α,β ] (0 ≤ α ≤ β ≤ 1). The concept extent is an object sets which meet the properties in the intent in the interval [ α,β ] 0 ≤ α ≤ β ≤ 1. It has been proved that interval concept lattice degenerate into classic concept lattice when ( α = β = 1), and when ( α > 0, β = 1), interval concept lattice degenerate into rough concept lattice. Then some unique properties of interval concept lattice have been proved. The construction algorithm of interval concept lattice was designed. Finally, the necessity and practicability were verified through a case study.

PL

W klasycznej i przybliżonej kracie pojęć ich obszar obejmuje każdy lub czasami tylko jeden atrybut. A więc podstawa i stopień poufności wydobywanych relacji mogą zostać poważnie zredukowane. Aby rozwiązać ten problem autorzy proponują nową strukturę kraty pojęć: przedziałową kratę pojęć Lαβ (Mα, Mβ,Y) zdefiniowaną w przedziale [ α,β ] (0 ≤ α ≤ β ≤ 1). Udowodniono, że przedziałowa krata pojęć przekształca się w klasyczną jeśli ( α = β = 1) i w przybliżoną gdy ( α > 0, β = 1). Zbadano unikalne własności kraty przedziałowej i zaprojektowano algorytm jej budowy. W końcu zweryfikowano , w przypadku studialnym, potrzebę jej wprowadzenia i możliwość wykonania.

14

Multiple Support Vector-based approach to Breast tumor recognition

Jiang H., Chen X., Liu B.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 5b

105-107

EN

Based on Multi-Support Vector Machine (MSVM),this paper provides a method of MSVM for breast tumor recognition to solve unfixed size and individual difference with the breast tumor. Support Vector Machine (SVM) on the eight direction of bump area is taken to generate vector classifier and to select Gauss kernel function as kernel function. The system application and test shows that the MSVM in breast tumor recognition achieved good result, and provide the reliable basis for further medical diagnosis. The breast tumor recognition accuracy achieved 97.3%.

PL

Opisano wykorzystanie metody MSVM (multi-support vector machine) do wykrywania guza piersi. Metoda generuje klasyfikator wektorowy w ośmiu kierunkach a selekcję cech przeprowadza się wykorzystując funkcje Gaussa jako kernel.

15

Modeling, Control and Implementation of a Lithium-ion Battery Charger in Electric Vehicle Application

Hu G., Duan S., Cai T., Liu B.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 1b

255-258

EN

The rapid development of Electric Vehicle powered by lithium-ion battery has resulted in significant interesting to charging device. However, the nonlinear characteristics of lithium-ion battery increase the complexity of charger designing. In this paper, to overcome the disadvantages, battery model is established and its parameters are evaluated adopted an exponential fitting method. Then an appropriate control strategy is proposed based on small signal model to realize the proposed charging strategy. Finally, experimental results from a laboratory prototype are shown to verify the feasibility of the proposed strategies.

PL

W pracy przedstawiono układ ładowania baterii litowych stosowanych w pojazdach elektrycznych. Problemem jest nieliniowa charakterystyka baterii dlatego układ musi mieć odpowiedni system sterowania zapewniający właściwą strategię ładowania.

16

An Improved Double Closed Loop Control Strategy for Air Plasma Cutting Converter

Liu B., Duan S., Li X.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 2

278-282

EN

A double closed loop control strategy composed of inner voltage-loop and external current-loop with a current-reference feedforward link was proposed based on the output characteristic of an air plasma cutting converter(APCC) with non-contact arc ignition. An equivalent mathematical model of the APCC was presented and a controller was designed via frequency domain analysis. Experiments verified that the proposed control strategy showed excellent dynamic and static performance, which significantly improved the arc ignition and the robustness against load disturbance.

PL

Przedstawiono strategię sterowania konwertera do cięcia plazmowego z podwójną pętlą złożoną z wewnętrznej pętli napięcia i zewnętrznej prądowej. Przedstawiono model matematyczny i projekt z analizą w domenie częstotliwości. Obiekt sprawdzono eksperymentalnie.

17

Active-Disturbance Rejection Control for a Direct-Drive Valve based on a linear motor

Gao Y., Liu B.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 5b

40-43

EN

A novel control scheme for a linear motor drive is proposed in this paper. Voice coil motor VCM, as one of the linear motors, which is widely used in the field of direct drive servo valve (DDV) with superior performance, has high accuracy and fast transient response. However, there are such uncertainties as unpredictable hydraulic resistance and estimated errors of the VCM model in this system, which may influence the accuracy and the rapid response of the control. In this paper, ADRC is applied to the system, which has strong robustness. Simultaneously, a novel hardware structure of motor control system based on field programmable gate array (FPGA) and digital signal processor (DSP) is implemented to realize the proposed algorithm. Both simulation and experimental results verify that the scheme proposed can attenuate the influences by the uncertainties of the model sharply. Also, the static and dynamic performances of the control system have been improved greatly with strong robustness to disturbances. Furthermore, the rapidness of the system has been improved greatly.

PL

W artykule przedstawiono system sterowania silnikiem liniowym ADRC bazujący na układach FPGA i wykorzystujący procesor sygnałowy. Silnik typu VCM (voice coil motor) jest używany do servo zaworu.

18

Acoustic frequency dependence of transmission characteristics in fiber acoustic gratings

Zhang H., Liu B., Tao J., Dong H., Guo T., Zhang M.

Optica Applicata

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2011

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Vol. 41, nr 4

817--823

EN

The dependence of transmission characteristics on acoustic frequency for an SMF-based acousto-optic tunable filter has been investigated in this paper. Experimental results indicate that multi-resonance peaks may turn up in the transmission spectrum when applied acoustic frequency is sufficiently high, and resonance wavelengths increase in proportion to the applied acoustic frequency for short resonance wavelength region, while they have opposite acoustic frequency responses for longer resonance wavelength region. Our numerical simulation proves that this phenomenon could be attributed to the non-monotonic phase matching curves of acoustic gratings, which would be helpful for the understanding of mode coupling mechanism in fiber acoustic gratings and design of fiber-based acousto-optic devices.

19

Temperature-insensitive displacement sensor based on high-birefringence photonic crystal fiber loop mirror

Zhang H., Liu B., Wang Z., Luo J., Wang S., Jia C., Ma X.

Optica Applicata

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2010

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Vol. 40, nr 1

209--217

EN

A temperature-insensitive displacement sensor based on high-birefringence photonic crystal fiber loop mirror (Hi-Bi PCFLM) is proposed. Through the measurement of transmission peak wavelength of the Hi-Bi PCFLM, this displacement sensor quantifies the free end displacement of a uniform-strength cantilever beam, on which part of Hi-Bi PCF is pasted. We have theoretically analyzed its operation principle, which is validated by our experimental results. This displacement sensor has the sensitivity of 0.28286 nm/mm and 0.27024 nm/mm over a range from -21 mm to 21 mm for two adjacent peak wavelengths, respectively. Experimental observation indicates that this sensor has good stability through a temperature range from 40 °C to 109.5 °C.

20

Nonlinearity-controllable all-optical logic gates based on broadband defect mode

Liu B., Tian H., Lu H., Ji Y.

Optica Applicata

|

2010

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Vol. 40, nr 3

657--668

EN

To avoid the adverse effect of unstable nonlinear progress on the design of all-optical logic gates, the broadband defect mode of one-dimensional photonic crystal with dual-defects has been studied. By using transfer matrix method, influences of period number and refractive indices on crystal’s transmission spectrum are analyzed. It is pointed out that with proper parameters, broadband defect mode, which could be used to reduce the influence between the nonlinear refractive index and field distribution, can be gained. Due to this fact, the designed XOR, AND and NOT logic gates can be steadily controlled with low-threshold and high-contrast.