Wyniki wyszukiwania - BazTech

1

Effect of reinforcement ratio and vertical load level on lateral capacity of bridge pile foundations

Fan Q., Gao Y.

Polish Maritime Research

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2018

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S 3

120--126

EN

The bearing response of pile foundations for cross-sea bridge subjected to lateral loading is investigated through threedimensional finite element numerical analyses. In the analyses, non-linear behavior of concrete is simulated using smeared cracking model, and the strain-stress relationship of rebar is modeled through perfectly elasto-plastic model obeying Mises yield criterion. The finite element model is validated against published lateral static loading test in situ. The effect of reinforcement ratio of reinforced concrete and vertical load level is explored on the displacement of pile head and lateral capacity of pile. The results show that for the pile with low reinforcement ratio, the allowable lateral capacity is controlled by concrete cracking, however the allowable lateral capacity is controlled by the displacement of pile head with high reinforcement ratio. The vertical load applied on the pile head may reduce its displacement but increase simultaneously the maximum moment in the pile body. Therefore, the optimum vertical load level is 0.4~0.6 times of the vertical ultimate load of a single pile.

2

Effect of Sulfur and Acid Soluble Aluminum Content on Precipitate and Microstructure of Grain-Oriented Silicon Steel

Zhou B., Zhu C., Li G., Luo Z., Gao Y., Bao S., Schneider J.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 4

1701--1708

EN

The combined effect of sulfur (S) and acid soluble aluminum (Als ) content on precipitates and microstructures in grain-oriented silicon steel were investigated. The results show that there are dominant AlN and a little amount of MnS-AlN composite in annealed hot-rolled band, and the amount of precipitates increases distinctly with increasing Als content, while S content plays a negligible role. The inhibitors that precipitate during hot band annealing can restrain the grain growth during hot band annealing and primary annealing, and the smaller grains of annealed hot-rolled band can contribute to the formation of {111} <112> texture during primary annealing. Lower S content is conducive to the formation of {111} <112> texture during primary annealing by promoting the formation of Goss texture during hot rolling.

3

A Visual Detection Method of Longitudinal Crack Based on Computer Image Processing During Slab Continuous Casting

Liu Y., Wang X., Sun Y., Du F., Gao Y., Wang F., Wang J.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 2

673--680

EN

Based on the mould temperature measured by thermocouples during slab continuous casting, a difference of temperature thermograph is developed to detect slab cracks. In order to detect abnormal temperature region caused by longitudinal crack, the suspicious regions are extracted and divided by virtue of computer image processing algorithms, such as threshold segmentation, connected region judgement and boundary tracing. The abnormal regions are then determined and labeled with the eight connected component labeling algorithm. The boundary of abnormal region is also extracted to depict characteristics of longitudinal crack. Based on above researches, longitudinal crack with abnormal temperature region can be detected and is different from other abnormalities. Four samples of temperature drop are picked up to compare with longitudinal crack on the abnormal region formation, length, width, shape, et al. The results show that the abnormal region caused by longitudinal crack has a linear and vertical shape. The height of abnormal region is more than the width obviously. The ratio of height to width is usually larger than that of other temperature drop regions. This method provides a visual and easy way to detect longitudinal crack and other abnormities. Meanwhile it has a positive meaning to the intelligent and visual mould monitoring system of continuous casting.

4

Research on the statistical characteristics of crosstalk in naval ships wiring harness based on Polynomial Chaos Expansion method

Chi Y., Li B., Yang X., Wang T., Yang K., Gao Y.

Polish Maritime Research

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2017

|

S 2

205--214

EN

Crosstalk in wiring harness has been studied extensively for its importance in the naval ships electromagnetic compatibility field. An effective and high-efficiency method is proposed in this paper for analyzing Statistical Characteristics of crosstalk in wiring harness with random variation of position based on Polynomial Chaos Expansion (PCE). A typical 14-cable wiring harness was simulated as the object of research. Distance among interfering cable, affected cable and GND is synthesized and analyzed in both frequency domain and time domain. The model of naval ships wiring harness distribution parameter was established by utilizing Legendre orthogonal polynomials as basis functions along with prediction model of statistical characters. Detailed mean value, mean square error, probability density function and reasonable varying range of crosstalk in naval ships wiring harness are described in both time domain and frequency domain. Numerical experiment proves that the method proposed in this paper, not only has good consistency with the MC method can be applied in the naval ships EMC research field to provide theoretical support for guaranteeing safety, but also has better time-efficiency than the MC method. Therefore, the Polynomial Chaos Expansion method.

5

Synergic Effect of sodium oleate (NaOL) and benzohydroxamic acid (BHA) on flotation of wolframite

Bu H., Cao M., Gao Y., Huang H.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 1

82--93

EN

In this work, two collectors sodium oleate (NaOL) and benzohydroxamic acid (BHA) were used to study the synergic effect in wolframite flotation. The flotation behaviour of these collectors was investigated at various NaOL:BHA ratios. Results show that the mixtures of NaOL with BHA of different ratios result in large improvements in the recovery of wolframite and the 9:1 NaOL:BHA ratio of collector mixture produced the highest wolframite recovery. The amount of NaOL and BHA adsorbed on wolframite was measured for these various reagent mixtures. Compared with pure NaOL, the addition of a certain proportion of BHA is beneficial for NaOL adsorption. Molecular dynamics simulations indicate the formation of HOL–HA (oleic acid–benzohydroxamic acid) complex can take place spontaneously in NaOL–BHA system. Additionally, HOL–HA complex interact with the huebnerite (MnWO4) surface more easily than NaOL–HOL (the highest surface active composition in sodium oleate) and the addition of BHA enable the H of carboxyl group in HOL to generate hydrogen bonds with O atoms of huebnerite surface, resulting in a stronger affinity of mixed surfactants. These results reveal that in a binary NaOL–BHA system, the BHA can encourage greater adsorption of the NaOL.

6

Effects of Abietinella abietina Extracts on the Germination and Seedling Emergence of Picea crassifolia: Results of Greenhouse Experiments

Wang Q., Zhao C., Gao Y., Gao C., Qiao Y., Xie H., Wang W., Yuan L., Liu J., Ma W., Li W.

Polish Journal of Ecology

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2016

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Vol. 64, nr 3

357--368

EN

Moss cushion plays an important role in recruitment of vascular plants. In this study, we examined the effects of water soluble extracts (WSE) of Abietinella abietina on germination of Qinghai spruce (Picea crassifolia) and the effects of moss substrates (A. abietina) on seedling emergence of P. crassifolia in two greenhouse experiments. We found that the WSE of moss affected germination of P. crassifolia in two ways: (1) the WSE reducing the risk of fungal infection to the seeds, improve the germination rate; and (2) the WSE affects germination by its concentration, that is, low concentrations of WSE (i.e., 0.5 mg ml-1 and 5 mg ml-1) stimulate, while high concentrations (i.e., 50 mg ml-1) inhibit it. In seedling emergence experiments, we detected that the moss substrates (both thick and thin mosses) facilitate the emergence of P. crassifolia in dry and intermediate moisture conditions, but inhibit it in moist conditions. In bare soil, the P. crassifolia emergence was also controlled by moisture conditions; the highest (60%) and the lowest (35%) emergence occurred in the moist conditions and dry conditions, respectively. We also found that P. crassifolia seedlings were thinner and taller, but their number higher in moss cushion than in bare soil. Thus we conclude that there is nurse effect of A. abietina cushion on recruitment of P. crassifolia in both dry and intermediate moisture conditions.

7

Multi-direction digital moving mask method for fabricating continuous microstructures

Zhang Z, Gao Y, Luo N, Zhong K, Liu Z

Optica Applicata

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2015

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Vol. 45, nr 1

79--88

EN

The multi-direction digital moving mask method, employing the superposition of the exposure along various moving directions, is developed for fabricating continuous microstructures. The mask pattern corresponding to each moving direction is determined by projecting the target dose profile in the corresponding moving direction. All the mask patterns are dynamically exposed on the same substrate layer by layer so as to form a 3D profile of the exposure dose. The selection criterion of a quantization number and moving-direction number is discussed. For verification of the multi-direction moving method, experiments are performed to fabricate a square pyramid array and square-based microlens array by moving along two orthogonal directions, and round-based microlens array by moving along six directions.

8

Simulation of the thermo-optic coupling effect in mid-infrared second harmonic generation of ZnGeP2 crystal

Zhang W., Gao Y., Huang J., Zhang G., Andreev Y. M., Grechin S. G., Lanskii G. V.

Materials Science Poland

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2015

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Vol. 33, No. 2

391--396

EN

The thermo-optic coupling process of second harmonic generation was numerically simulated in ZnGeP2 crystals pumped by a pulsed CO2 laser at the wavelength of 9.6 mu m, under the strong and weak cooling conditions. The conversion efficiencies, temperature distributions were calculated during the evolution of the thermo-optic coupling. The results showed that the thermo-optic coupling was weak in the strong cooling condition, which nearly did not disturb the conversion processes and temperature distribution, while in the weak cooling case, the temperature distribution showed a great influence on the conversion efficiency and light intensity. Finally, it was found that compensation of the phase mismatch induced by the thermal effect can well recover the conversion efficiency.

9

Certificate-based Fair Exchange Protocol of Schnorr Signatures in Chosen-key Model

Shao Z., Gao Y.

Fundamenta Informaticae

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2015

|

Vol. 141, nr 1

95--114

EN

This paper proposes the first optimistic protocol to accomplish the fair exchange of standard Schnorr signatures in the chosen-key model, in which each participant is allowed to choose his Schnorr key pair freely without showing his knowledge of the private key. Besides solving the authentication problem of public keys, the protocol relaxes excessive trust on the adjudicator since the adjudicator needs to be trusted only by the signer. The protocol is secure against three types of inside adversaries under the DL assumption in the random oracle model. It suits much more the actual circumstances of the Internet.

10

Relationship between flotation and Fe/Mn ratio of wolframite with benzohydroxamic acid and sodium oleate as collectors

Yang S., Feng Q., Qiu X., Gao Y., Xie Z.

Physicochemical Problems of Mineral Processing

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2014

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Vol. 50, iss. 2

747--758

EN

Several studies revealed that flotation of wolframite changes with different Fe/Mn ratios, but they did not reach a consensus. This relationship in the presence of benzohydroxamic acid (BHA) and sodium oleate (NaOl) as collectors was studied in this paper through comparison of probability distribution curve of wolframite with different Fe/Mn ratios between the raw ore and the flotation concentrate, the pure mineral flotation and solution chemistry of flotation. The results showed that wolframite with high Fe/Mn ratio showed higher flotation with BHA as a collector while the flotation behavior of wolframite was completely opposite with NaOl as a collector. Besides, the calculations of chemical equilibrium in the solution were plotted as ΔG°-pH graphs. The results revealed that the flotation of wolframite may be determined by the interaction between BHA and ferric(II) ion or between NaOl and manganous ion. From the perspective of collector mixture, the results also explain the high collecting capability of the BHA/NaOl collector mixture, which can be defined as “functional complementation”.

11

Influence of alpha and gamma radiolysis on Pu retention in the solvent TBP/kerosene

Gao Y, Zheng W., Cao X., Chen S.

Nukleonika

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2014

|

Vol. 59, No. 4

123--128

EN

In light of the issue of radiolysis of the solvent system in PUREX process, alpha and gamma radiation stability of tributyl phosphate (TBP)/kerosene (OK) have been studied in this paper, in which 238Pu dissolved in the organic phase and 60Co are selected as alpha and gamma irradiation sources, respectively. The amount of the degradation products not easily removed after the washing process has been measured by the plutonium retention. The effects of the absorbed dose, the TBP volume fraction, the cumulative absorbed dose and the presence of UO2 2+ and Zr4+ on the radiolysis of the solvents have been investigated. The results have indicated that the Pu retention increases with the increase of the absorbed dose after alpha or gamma irradiation, and is larger for the solvent containing less TBP. There is competition between UO2 2+ and Pu4+ to complex with the degradation products, and Zr4+ accelerates the radiolysis of the system.

12

Preparation of ITO films using a spray pyrolysis solution containing an acetylacetone chelating agent

Gao Y., Zhao G., Duan Z., Ren Y.

Materials Science Poland

|

2014

|

Vol. 32, No. 1

66--70

EN

Indium tin oxide (ITO) films were deposited on soda-lime glass substrates by the spray pyrolysis method using a spray solution of InCl33H2O as a precursor, SnCl45H2O as a dopant and acetylacetone (AcAcH) as a chelating agent. The effect of the addition of AcAcH to the spray solution on the surface morphology of the ITO film was investigated. The surface quality of the film prepared from the spray solution with AcAcH was better than that without AcAcH. The ITO film with the thickness of 230 nm, using the spray solution with AcAcH, exhibited the lowest resistivity of 4.75 × 10􀀀4 Wcm and higher optical transmittance of 85 %, respectively.

13

Research on Improved LEACH Protocol of Wireless Sensor Networks

Shan J., Dong L., Liao X., Shao L., Gao Z., Gao Y.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

75--77

EN

This investigation was performed to see if the improved LEACH protocol operates more effectively than the traditional LEACH protocol. The improved protocol adds energy factor and distance factor to the threshold T(n). The multi-hop routing algorithm of cluster head is introduced too, it based on the hop count and the remaining energy. MATLAB was used to simulate. The simulation data suggests that the death rate of nodes of the improved protocol was lower than the traditional one. It is concluded that the improved LEACH protocol can balance network load and extend the life-cycle of network.

PL

Zbadano efektywność pracy udoskonalonego, w stosunku do tradycyjnego, protokołu hierarchicznego klastrowania LEACH. Udoskonalenie protokołu polega na wprowadzeniu współczynników energii i odległości węzłów oraz wykorzystaniu ich przy obliczaniu wartości progowej T(n). Zastosowano również wielo-przeskokowy algorytm klastrowania węzła głównego. Algorytm działa na zasadzie liczenia przeskoków i zachowania energii. Do symulacji wykorzystano program MATLAB. Wyniki symulacji wykazują, że tempo uszkodzeń węzłów przy zastosowaniu udoskonalonego protokołu jest mniejsze niż w przypadku tradycyjnego. Podsumowując, udoskonalony protokół LEACH może zrównoważyć obciążenie i wydłużyć okres życia sieci.

14

Adaptive Improved RLS Algorithm for Blind Source Separation

Ou S., Wang X., Gao Y.

Przegląd Elektrotechniczny

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2013

|

R. 89, nr 3b

81--83

EN

Based on an adaptive combination of two RLS-type algorithms with different forgetting factor, an effective scheme is proposed to improve the performance of the RLS-type algorithm for blind source separation. A mixing parameter for adjusting the proportion of the two RLS algorithms is introduced in an attempt to put together the best properties of them, and its adaptive rule is obtained by means of a natural gradient criterion. Experimental results demonstrate the good performance of the proposed approach in different kinds of environments.

PL

W artykule przedstawiono nową, efektywniejszą strukturę algorytmu RLS do ślepej separacji sygnałów, bazującą na adaptacyjnej kombinacji dwóch takich algorytmów z różnymi współczynnikami ważenia. W celu uzyskania jak najlepszego wykorzystania ich własności, zastosowano parametr, który pozwala na ich dostrojenie. Wyniki eksperymentalne potwierdzają skuteczność działania.

15

Short-Term Wind Power Forecasting with Combined Prediction Based on Chaotic Analysis

Dong L., Gao S., Liao X., Gao Y.

Przegląd Elektrotechniczny

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2012

|

R. 88, nr 5b

35-39

EN

With the integration of wind energy into electricity grids, it is becoming increasingly important to obtain accurate wind power forecasts. In this paper, models for short-term wind power prediction in large wind farms are discussed. The analysis of modeling with low dimensions nonlinear dynamics indicates that wind power time series have chaotic characteristics and wind power can be predicted in the short-term. The wind power prediction models are built with phase space reconstruction method and the combination model with different embedding dimensions is tested.

PL

Opisano metodę krótkoterminowego prognozowania mocy elektrowni wiatrowych bazującą na chaotycznym charakterze wiatru w krótkich odstępach czasu.

16

Game-based Decentralized Charging Control for Large Populations of Electric Vehicles

Xie K., Dong L., Liao X., Gao Z., Gao Y.

Przegląd Elektrotechniczny

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2012

|

R. 88, nr 7b

252--255

EN

This paper proposes a game-based decentralized charging control strategy for large populations of electric vehicles (EVs). Assuming all EV owners make their own charging strategy according to the electricity price and the total electricity demand of the day before, the owners can be guided to actively participate in the game by a set of electricity pricing mechanism. The existence of Nash equilibrium and the global optimum (or ‘Valley-filling’) of the charging strategy are verified. Simulation results demonstrate the convergence to the Nash equilibrium within a few iterations.

PL

W artykule zaproponowano strategię ładowania dla dużej populacji pojazdów elektrycznych bazująca na teorii gier. Strategia wykorzystuje informacje o cenie energii i prognozowanym zapotrzebowaniu. Zweryfikowano metody optymalizacji.

17

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

Gao Y., Liu B.

Przegląd Elektrotechniczny

|

2012

|

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

Accurate Performance Analysis of DS/SS Systems in Single-tone Interference over Flat Fading Channels

Zang G., Gao Y.

Przegląd Elektrotechniczny

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2012

|

R. 88, nr 10a

197-200

EN

The performance analysis of DS/SS system in single-tone interference is usually presented for AWGN channel. While, there usually exists fading over the actual wireless channels. Using the well-known MGF-based analysis approach, the exact symbol error rate of DS/SS system in single-tone interference over flat fading channel is derived in this paper, and the application conditions of two familiar performance analysis methods — standard Gaussian approximation and improved Gaussian approximation for DS/SS system in single-tone interference are discussed.

PL

W artykule analizuje się wskaźnik błędu systemu telekomunikacyjnego DS/SS w kanale z zanikami przy jednotonowej interferencji. Do analizy wykorzystuje się metodę MGF. (Analiza dokładności systemu telekomunikacyjnego DS./SS z interferencją jednotonową w kanale z zanikami)

19

Three-dimensional microstructures of photoresist formed by gradual gray-scale lithography approach

Luo N, Gao Y, Zhimin Z, Mengchao X, Huaming W

Optica Applicata

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2012

|

Vol. 42, nr 4

853--864

EN

We describe a simple and reliable approach, by employing a gradual gray-scale lithography process, which is developed for the fabrication of continuous 3D microstructure. A matrix equation has been built to quantitatively calculate the pattern gray and exposure time by combining the digital micromirror device (DMD) modulation characteristics. To avoid DMD pixel error induced by sampling, we also propose a new quantifying method in accordance with DMD pixel dimension to further improve the fabrication precision of the 3D photoresist profile. Finally, different photoresist microstructures with continuous profile, including axicon array and microlens array, have been successfully fabricated.

20

State Complexity of Combined Operations with Union, Intersection, Star and Reversal

Gao Y., Yu S

Fundamenta Informaticae

|

2012

|

Vol. 116, nr 1-4

79-92

EN

In this paper, we study the state complexities of four combined operations: [formula]. The tight bounds for all these combined operations on regular languages are obtained and proved. We show that, as usual, they are different from the mathematical compositions of the state complexities of their individual participating operations.