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1

Identification of sonar detection signal based on fractional Fourier transform

Wang B., Tang J., Yu F., Zhu Z.

Polish Maritime Research

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2018

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S 2

125--131

EN

Aiming at the source of underwater acoustic emission, in order to identify the enemy emission sonar source accurately. Using the digital watermarking technology and combining with the good time-frequency characteristics of fractional Fourier transform (FRFT),this paper proposes a sonar watermarking method based on fractional Fourier transform. The digital watermark embedding in the fractional Fourier transform domain and combined with the coefficient properties of the sonar signal in the fractional Fourier transform to select the appropriate watermark position. Using the different characteristics of the signals before and after embedding, an adaptive threshold was set for the watermark detection to realize the discrimination of sonar signals. The simulation results show the feasibility and has better resolution and large watermark capacity of this method, while the robustness of the watermark is better, and the detection precision is further improved.

2

Synthesis, characterization of Hollandite Ag2Mn8O16 on TiO2 nanotubes and their photocatalytic properties for Rhodamine B degradation

Thabit M., Liu H., Zhang J., Wang B.

Polish Journal of Chemical Technology

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2018

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Vol. 20, nr 2

85--91

EN

In this research Ag2 Mn8 O16 nanocrysls/TiO2 nanotubes, photoelectrodes were successfully prepared through anodization and annihilation steps, followed by electrodeposition of MnO2 and Ag in a three electrodes cell. The obtained photoelectrodes were dried, then annealed for crystallization, the morphology and structure of the fabricated electrodes were characterized via scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The light absorption and harvesting properties were investigated through UV–visible diffuse refl ectance spectrum (DRS), photocatalytic performances were evaluated by degradation of 50 mL of Rhodamine B (5 mg L–1 ) under Xenon light irradiation for 2 h. Results illustrated that the fabricated photoelectrodes show remarkable photo-degradation properties of organic pollutants in aqueous mediums.

3

Preparation and Up-conversion Luminescence of Yb3+/Er3+/GZO Ceramics

Li G., Wang B., Wang R., Liu H.

Polish Journal of Chemical Technology

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2018

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Vol. 20, nr 3

15--19

EN

Yb3+/Er3+/GZO ceramics have been synthesized with high temperature solid-state method. The phase and structure of the Yb3+/Er3+/GZO ceramics were characterized by X-ray diffraction (XRD). The XRD pattern that following ions Yb3+ , Er3+ and Ga3+ were well doped into the ZnO lattice. Efficient visible up-conversion (UC) red and green emission were observed under 980 nm excitation. The mechanism of the UC luminescence is investigated on the basis of the UC luminescence emission spectra, the power curve and energy level diagram. The infl uence of doping ions to the intensity ratio of red to green is analyzed and high purity of red light (red/green = 29.9) is finally obtained.

4

The effect of hollow glass microspheres on the properties of high silica glass fiber fabric/liquid silicone rubber composite sheet

Chen S., Qin Y., Song Y., Wang B.

Polimery

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2018

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T. 63, nr 3

178--184

EN

In this study, high silica glass fiber fabric/liquid silicone rubber (HSGFF/LSR) composite sheet filled with hollow glass microspheres (HGM) was prepared. The effects of HGM content on the mechanical, thermal insulation and dynamic mechanical properties of the composite sheet were investigated. The results showed that the compatibility and interfacial properties between HGM and the matrix were improved after the HGM was treated with a silane coupling agent, KH550. Composite, in which the HGM content was 7 % by weight, shows the most advantageous mechanical, insulating and damping properties.

PL

Na bazie tkaniny z włókien kwarcowych (HSGFF) nasyconej ciekłym kauczukiem silikonowym (LSR) otrzymywano kompozyty napełniane mikrosferami szklanymi (HGM). Badano wpływ dodatku mikrosfer na właściwości mechaniczne, izolacyjność cieplną i właściwości dynamiczno-mechaniczne kompozytowych arkuszy. Stwierdzono, że modyfikacja mikrosfer szklanych za pomocą silanowego czynnika sprzęgającego KH550 poprawiła kompatybilność i oddziaływania międzyfazowe cząsteczek HGM i nasyconej ciekłym kauczukiem tkaniny z włókien szklanych. Najkorzystniejsze właściwości mechaniczne, izolacyjne i tłumiące wykazywał kompozyt, w którym zawartość HGM wynosiła 7 % mas.

5

An Improved Secure Cloud Storage Auditing Protocol Based on Distributed String Equality Checking

Zhang J., Wang B.

Fundamenta Informaticae

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2018

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Vol. 157, nr 1/2

185--199

EN

Recently how to audit cloud storage correctly and securely is a very hot research topic for cloud storage. At Infocom 2015, Chen et al. proposed a novel secure cloud storage audit protocol based on distributed string equality checking, which is a very interesting result. In this paper, we give some improvements to their protocol to strengthen its security. In particular, we show that if the data owners reuse pseudorandom function on the same order number of file block when uploading file block's tag to the cloud, the protocol maybe not secure any more. We also show that there can exist P many (mi, ci) pairs which will result in the same inner product sum n ∑ni=1 mi . ci while mi denotes the file block, ci denotes the challenge value, and n denotes the number of blocks. We emphasis here that the flaw maybe does not lie in the traditional security model of cloud storage auditing protocol, but we think it is actually a serious drawback for current secure cloud storage audit protocols. We emphasis these two flaws can also exist in some famous cloud auditing protocols such as PDP and POR. Finally, we give an improvement to their protocol, and thus also give a way to strengthen the famous PDP and POR protocols.

6

Pre-formulation Compatibility Studies of 5-Amino-1H-tetrazole Nitrate with Several Typical Materials by Thermal and Non-thermal Techniques

Guo W., Han Z., Lin Q., Wang B.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 1

100--114

EN

The aim of the present study was to assess the physicochemical compatibility of a promising energetic salt, 5-amino-1H-tetrazole nitrate (5-ATN), with some typical materials. Thermal techniques (differential scanning calorimetry (DSC) and vacuum stability test (VST)) and non-thermal techniques (X-ray diffractometry (XRD) and Fourier Transform Infrared Spectroscopy (FTIR)) were applied. Five energetic materials (TNT, RDX, HMX, CL-20 and AP) and three common additives (Al, DOS and F2604-2) were tested to evaluate their compatibility with 5-ATN. Based on the DSC results, except for AP that was only partially compatible with 5-ATN, all of the selected materials exhibited good compatible with 5-ATN. The VST test further confirmed the compatibility of the 5-ATN/AP mixtures. Combined with the thermal methods, the FTIR results agreed with the DSC findings. The XRD results showed some differences.

7

Comparative Theoretical Investigation on Energetic Substituted Furazanyl Ethers

Liu N., Wang K., Shu Y., Zeman S., Wang B., Wang W.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 1

47--71

EN

Furazanyl ether has great potential to be an important candidate as a casting explosive and energetic plasticizer. The density functional theory (DFT) method was used to investigate the heats of formation (HOFs), molecular stability, detonation performance and melting point of a series of substituted furazanyl ethers at B3LYP/6-311G(d,p) level. The results show that the introduction of –N3 or –N(O)=N– groups significantly improves the HOFs values of the derivatives. The bond dissociation energies (BDEs) were analyzed, showing that the N–O bond in the furazan ring is the weakest for most compounds and the ring is vulnerable to cleavage in thermal decomposition. The calculation of density, detonation velocities and detonation pressures suggests that the substitution of –NF2, –CF(NO2)2, furoxan or –N(O)=N– group is an effective method for enhancing their detonation performance. The melting points were determined according to the variation of specific heat capacity, and good estimates were obtained in comparison with the available experimental data. Taking into account the detonation performance and melting point, four compounds are favoured for application in melt cast explosive or energetic plasticizers.

8

A study of interfacial heat transfer and its effect on quenching when hot stamping AA7075

Xiao W., Wang B, Zheng K., Zhou J., Lin J.

Archives of Civil and Mechanical Engineering

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2018

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Vol. 18, no. 3

723--730

EN

The aim of this research was to investigate the effects of contact pressure and lubrication on the interfacial heat transfer coefficient (IHTC) between AA7075 sheet and H13 tool steel and the in-die quenching performance in hot stamping. Firstly, a series of designed in-die quenching experiments were performed using different contact pressures, 0.05–30 MPa and lubrication conditions to determine the IHTC values using an efficient methodology. Secondly, temperature evolution of the tools and blank during the in-die quenching was investigated. Mechanical properties of material in-die quenched under different process conditions, were measured to determine their relation to quench conditions. The results have shown that IHTC values increased with increasing contact pressure and use of lubricant. A strength level of T6 condition could be obtained using a contact pressure greater than 5 MPa in the lubricated condition.

9

Analysis and Modelling on Radiated Noise of a Typical Fishing Boat Measured in Shallow Water Inspired by AQUO Project’s Model

Peng Z., Fan J., Wang B.

Archives of Acoustics

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2018

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Vol. 43, No. 2

263--273

EN

The shipping noise near channels and ports is an important contribution to the ambient noise level, and the depth of these sites is often less than 100 m. However less attention has been paid to the measurement in shallow water environments (Brooker, Humphrey, 2016). This paper presents extensive measurements made on the URN (underwater radiated noise) of a small fishing boat in the South China Sea with 87 m depth. The URN data showed that the noise below 30 Hz was dominated by the background noise. The transmission loss (TL) was modelled with FEM (finite element method) and ray tracing according to the realistic environmental parameters in situ. The discrepancy between the modelled results and the results using simple law demonstrates both sea surface and bottom have significant effect on TL for the shallow water, especially at low frequencies. Inspired by the modelling methodology in AQUO (Achieve QUieter Oceans) project (Audoly et al., 2015), a predicted model applied to a typical fishing boat was built, which showed that the URN at frequencies below and above 100 Hz was dominated by non-cavitation propeller noise and mechanical noise, respectively. The agreement between predicted results and measured results also demonstrates that this modelling methodology is effective to some extent.

10

Hexahydroquinoline derivatives : synthesis and anti-hepatoma cancer activity

Wang B., Jin W.-X., Zhang Y.-L., Huang L.

Przemysł Chemiczny

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2017

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T. 96, nr 4

897--900

EN

Arom. aldehydes were condensed in EtOH under boiling, pptd. by cooling to the room temp., sepd. by filtration, dried under vacuum and studied for anticancer activity against 3 human hepatoma tumor cell lines (SMMC-7721, BEL-740 and HCCLM3). Normal fibroblast cells WI 38 were also used. Fluorouracil was used as a ref. anticancer agent. One of the synthesized comps. showed a high inhibitory effect against 3 tumor cell lines (higher than the ref. agent). The compd. was non-cytotoxic to normal cells (IC50 values higher than 100 μg/mL).

PL

Przedstawiono syntezę i charakterystykę 4 pochodnych heksahydrochinoliny. Związki te zsyntetyzowano w reakcji kondensacji różnych aldehydów aromatycznych i oceniono pod kątem właściwości antyrakowych na podstawie badania 3 ludzkich linii komórkowych raka wątrobowokomórkowego (SMMC-7721, BEL-740 i HCCLM3). W badaniu wykorzystano także komórki WI 38 jako normalne fibroblasty. Najlepsze wyniki uzyskano dla związku 4, który wykazał najskuteczniejsze działanie hamujące rozwój 3 linii komórek rakowych. Działanie to okazało się skuteczniejsze niż w przypadku referencyjnego fluorouracylu. Ponadto związek ten nie działał cytotoksycznie na normalne komórki (IC₅₀ > 100 μg/mL).

11

Underwater target direction of arrival estimation by small acoustic sensor array based on sparse bayesian learning

Wang B., He C.

Polish Maritime Research

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2017

|

S 2

95--102

EN

Assuming independently but identically distributed sources, the traditional DOA (direction of arrival) estimation method of underwater acoustic target normally has poor estimation performance and provides inaccurate estimation results. To solve this problem, a new high-accuracy DOA algorithm based on sparse Bayesian learning algorithm is proposed in terms of temporally correlated source vectors. In novel method, we regarded underwater acoustic source as a first-order auto-regressive process. And then we used the new algorithm of multi-vector SBL to reconstruct the signal spatial spectrum. Then we used the CS-MMV model to estimate the DOA. The experiment results have shown the novel algorithm has a higher spatial resolution and estimation accuracy than other DOA algorithms in the cases of less array element space and less snapshots.

12

Fabrication of Titanium dioxide nanotube photo-electrodes in different electrolyte mixtures and the impacts on their characteristics and photo-catalytic abilities under visible light

Liu M-T., Zhang J., Wang B.

Polish Journal of Chemical Technology

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2017

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Vol. 19, nr 1

34--40

EN

TiO2 nanotube arrays were fabricated using electrochemical anodization of titanium foils, where different types of electrolytes were tested to determine conceptual choice for nanotubes fabrication. These electrolytes are 1M (NH4)2SO4 containing 0.5% wt NH4F, 1M Na2SO4 containing 0.5% wt NH4F, 1M NaF containing 0.5% wt (NH4)2SO4 and a mixture of water: ethylene glycol 1:9 containing 0.5% wt NH4F. The foils were marked as EG type (Ethylene Glycol), AS type (Ammonium sulfate), SS type (sodium sulfate) and SF type (sodium fluoride). The photocatalytic capabilities and characterization of the fabricated NTAs were analyzed using SEM, XRD, and DRS. The degradation ratio of designated organic pollutants (Rhodamine B) was analyzed. The obtained results have proven that foils fabricated using Ethylene glycol have significant photocatalytic abilities, with a degradation ratio of EG-SS-SF-AS types being 80% to 85%, 70% to 80%, 70% to 75% and 52% to 55%, respectively.

13

Effects of vinasse and silica mud on the performance of thermophilic fermentation of brewery sludge from brewery waste substrates

Xin Y., Shen J., Wang B., Zhu X., Wang Y., Wang G., Chen Q.

Environment Protection Engineering

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2017

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Vol. 43, nr 2

119--127

EN

The anaerobic digestion of mixing brewery sludge with vinasse and silica mud at various ratios under thermophilic conditions was explored. Vinasse, silica mud and beer sludge (the sludge from the treatment of beer wastewater) are the main solid wastes of the beer production. Uncontrolled decom-position of these wastes could cause large-scale contamination of soil, water, and air. The results of the investigation showed that the optimal ratio of beer sludge and vinasse was 1:1 under total solids of 10%, producing the highest amount of gas of 1.34 cm3/g within 24 h and 4.06 cm3/g in 10 days. The silica mud weakened the fermentation process and reduced the gas production, and the concentration of total organic carbon, total nitrogen and volatile solids decreased during the digestion. For the mixture of brewery sludge and vinasse, the content of the total organic matter in the biogas manure was more than 60% and the value of pH was 6.5 after the anaerobic digestion, indicating that the manure can be used as an organic fertilizer.

14

Thermal effect on the dynamic error of a high-precision worktable

Zou H., Wang B.

Archives of Civil and Mechanical Engineering

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2017

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Vol. 17, no. 2

336--343

EN

This paper investigates the thermal effect on the dynamic error of a high-precision machine worktable during operation. The thermo-mechanical model was established to obtain the motion errors of the worktable by considering the combined effects of varying internal heat sources and external thermal drifts. The temperature tests were performed to obtain the initial conditions of the model and provide a verification for the analytical convection coefficients and heat flux, which were obtained by inverse analysis. The predicted yawing errors of the worktable were confirmed by interferometer tests. Numerical and experimental results suggest that the environmental temperature fluctuation is the largest contributor to the motion errors of the worktable, and they increase with the increasing of environmental temperature. This study allows deeper insights into the underlying mechanisms that result in the motion accuracy variations of the worktable due to the thermal effects, which can provide a strategy for manufacture to further compensate the thermal error and realize ultra precision.

15

Highly-efficient three-port output by metal-mirror-based grating

Li H., Wang B., Shu W., Chen L., Lei L., Zhou J.

Optica Applicata

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2016

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Vol. 46, nr 1

87--92

EN

A highly-efficient three-port output of metal-mirror-based grating is proposed in this paper. The metal-mirror-based grating can function as a beam splitter which can diffract the normal incident wave into the 0th and the +/- 1st orders for both TE and TM polarizations with the usual duty cycle of 0.5. The analysis of the grating parameters can be optimized by rigorous coupled-wave analysis. The high efficiency for TE and TM polarizations shall be realized. By means of the numerical simulation, the depth and connecting layer thickness of grating can be accurately calculated. The efficiency of per port is near 33.3%, so the novel three-port output grating with a connecting layer would be an excellent optical element.

16

Logic Programming with Graded Introspection

Zhang Z., Wang B., Zhang S.

Fundamenta Informaticae

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2016

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Vol. 147, nr 1

133--158

EN

This paper develops a logic programming language, GI-log, that extends answer set programming language with a new graded modality Kω where ω is an interval satisfying ω ⊆ [0; 1]. The modality is used to precede a literal in rules bodies, and thus allows for the representation of graded introspections in the presence of multiple belief sets: KωF intuitively means: it is known that the proportion of the belief sets where F is true is in the interval ω. We define the semantics of GI-log, study the relation to the languages of strong introspections, give an algorithm for computing solutions of GI-log programs, and investigate the use of GI-log for formalizing contextual reasoning, conformant planning with threshold, and modeling a graph problem.

17

Effect of grain size on the fatigue crack growth behavior of 2524-T3 aluminum alloy

Shou W. B., Yi D. Q., Liu H. Q., Tang C., Shen F. H., Wang B.

Archives of Civil and Mechanical Engineering

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2016

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Vol. 16, no. 3

304--312

EN

2524-T3 aluminum alloy sheets with different grain sizes (13 μm, 59 μm, 178 μm, 355 μm, 126 μm, and 87 μm) were prepared using methods such as rolling and annealing. The microstructures and mechanical properties of the 2524-T3 aluminum alloy sheets were studied using optical microscopy (OM), scanning electron microscopy (SEM), and tensile and fatigue crack growth (FCG) rate tests. The grain size had a significant effect on the fatigue crack growth (FCG) rate. Alloys with grain sizes between 50 and 100 μm exhibited high fatigue crack propagation resistances and the lowest FCG rates (da/dN = 1.05–1.45 × 10−3 mm/cycle at ΔK = 30 MPa m1/2). Microstructural observations revealed that fatigue cracks propagated more tortuously in the alloy with grain sizes within the range of 50–100 μm. This result is attributed to the combined effects of grain boundaries, crack deflection, fracture surface roughness-induced crack closure, and plasticity-induced crack closure.

18

Three-port beam splitter based on a sandwiched grating with an improved aspect ratio

Shu W, Wang B, Li H, Li W, Chen L., Lei L., Zhou J.

Optica Applicata

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2015

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Vol. 45, nr 3

279--284

EN

In this paper, a fused-silica transmission grating used as a three-port beam splitter is designed by using the rigorous coupled-wave analysis, which is based on the sandwiched grating structure at the wavelength of 800 nm under normal incidence. Firstly, it is feasible to realize such a grating with the prescribed grating duty cycle and grating period. Next, high efficiency can be also achieved for both TE and TM polarizations. Moreover, the aspect ratio of the grating depth to the ridge width can be improved, which is significant for practical applications. At last, the three-port beam splitter is designed with a covering layer on the surface, which can extend its life service.

19

Polarization-independent metal-dielectric grating with improved bandwidth

Wang B, Li H, Shu W, Li W, Li C, Lei L, Zhou J

Optica Applicata

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2015

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Vol. 45, nr 1

71--77

EN

A polarization-independent reflective grating with improved bandwidth is presented based on the mixed metal-dielectric grating. The novel grating is composed of the substrate, the metal slab, two dielectric layers, and the covering layer. The grating parameters are optimized for the special duty cycle of 0.6 at an incident wavelength of 1550 nm used in dense wavelength division multiplexing (DWDM). With the designed grating, high efficiency can be diffracted into the reflective –1st order for both TE and TM polarizations, where the polarization-independence is exhibited. Most importantly, the efficiency of more than 90% can be achieved within the incident wavelength bandwidth of 1262–1686 nm, where the bandwidth is improved greatly compared with the reported surface-relief single-layer grating. The reflective grating can have advantages of high efficiency, polarization-independence, and wide bandwidth, which should be useful for DWDM applications.

20

Preorder Information Based Attributes’ Weights Learning in Multi-attribute Decision Making

Wang B., Liang J., Qian Y.

Fundamenta Informaticae

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2014

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Vol. 132, nr 3

331--347

EN

Choquet integral, as an adequate aggregation operator, extends the weighted mean operator by considering interactions among attributes. Choquet integral has been widely used in many real multi-attribute decision making. Weights (fuzzy measures) of attribute sets directly affect the decision results in multi-attribute decision making. In this paper, we aim to propose an objective method based on granular computing for determining the weights of the attribute sets. To address this issue, we first analyze the implied preorder relations under four evaluation forms and construct the corresponding preorder granular structures. Then, we define fuzzy measure of an attribute set by the similarity degree between a special preorder pairs. Finally, we employ two numerical examples for illustrating the feasibility and effectiveness of the proposed method. It is deserved to point out that the weight of each attribute subset can be learned from a given data set by the proposed method, not but be given subjectively by the decision maker. This idea provides a new perspective for multi-attribute decision making.