Wyniki wyszukiwania - Biblioteka Nauki

1

Chinese Syllable and Phoneme Identification in Noise and Reverberation

100%

Peng J.

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2014

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tom Vol. 39, No. 4

483--488

EN

Chinese is a tonal language, which differentiates it from non-tonal languages in the Western countries. A Chinese character consists of an initial, a final, and a tone. In the present study, the effects of noise and reverberation on the Chinese syllable, initial, final, and tone identification in rooms were investigated by using simulated binaural impulse responses through auralization method. The results show that the syllable identification score is the lowest, the tone identification score is the highest, and the initial iden- tification scores are lower than those of the final identification under the same reverberation time and signal-to-noise ratio condition. The Chinese syllable, initial, and final identification scores increase with the increase of signal-to-noise ratio and decrease of the reverberation time. The noise and reverberation have insignificant effects on the Chinese tone identification scores under most room acoustical environ- ments. The statistical relationship between the Chinese syllable articulation and phoneme articulation had been experimentally proved under different noise and reverberation conditions in simulated rooms.

2

Chinese Word Identification and Sentence Intelligibility in Primary School Classrooms

89%

Peng J. , Peng J.

Archives of Acoustics

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2016

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tom Vol. 41, No. 2

213--219

EN

The Chinese word identification and sentence intelligibility are evaluated by grades 3 and 5 students in the classrooms with different reverberation times (RTs) from three primary school under different signal-to-noise ratios (SNRs). The relationships between subjective word identification and sentence intelligibility scores and speech transmission index (STI) are analyzed. The results show that both Chinese word identification and sentence intelligibility scores for grades 3 and 5 students in the classroom increased with the increase of SNR (and STI), increased with the increase of the age of students, and decreased with the increase of RT. To achieve a 99% sentence intelligibility score, the STIs required for grades 3, grade 5 students, and adults are 0.71, 0.61, and 0.51, respectively. The required objective acoustical index determined by a certain threshold of the word identification test might be underestimated for younger children (grade 3 students) in classroom but overestimated for adults. A method based on the sentence test is more useful for speech intelligibility evaluation in classrooms than that based on the word test for different age groups. Younger children need more favorable classroom acoustical environment with a higher STI than older children and adults to achieve the optimum speech communication in the classroom.

3

The Effects of the Noise and Reverberation on the Working Memory Span of Children

63%

Jianxin P. , Peng J.

Archives of Acoustics

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2018

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tom Vol. 43, No. 1

123--128

EN

Three different reverberation time (RT) conditions were obtained by room acoustical simulation. The working memory span of grades 3 (8 to 9 years old) and 6 children (11 to 12 years old) was tested under these reverberation conditions with different signal-to-noise ratio (SNR) by headphone reproduction in a quiet classroom. The working memory span scores (WMSSs) were obtained under the different RTs and SNRs conditions. The results demonstrated that children’s age, RT and SNR had significant effect on children’s WMSSs. With the increase of SNR and the decrease of RT, the WMSSs increased gradually. Under the same SNR and RT condition, the children’s WMSSs were increased with the increase of their age. Multiple linear regression analysis shows that children’s WMSSs are related to age, RT and SNR, and the correlation coefficient is 0.99.

4

Improvement and invariance analysis of Zernike moments using as a region-based shape descriptor

63%

Ye B. , Peng J.

Image Processing & Communications

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2002

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tom Vol. 8, no 3

11-20

EN

In order to retrieve an image from a large image database, the descriptor should be invariant to scale and rotation. It must, also have enough discriminating power and immunity to noise for retrieval from a large image database. The Zernike moment descriptor has manv desirable properties such as rotation invariance, robustness to noise, expression efficiency, fast computation and multi-level representation for describing the shapes of patterns, but it does not possess scale invariance. In this paper, we present an improved Zernike moment descriptor that not only has rotation invariance, but also has scale invariance. We apply the improved Zernike moments to image recognition using as an elective descriptor of global shape of an image in a large image database. The experimemtal results show that the improved Zernike moment has better invariant properties than unimproved Zernike moment using as region-based shape descriptor.

5

A Digital Image Encryption Algorithm Based on Hyper-chaotic Cellular Neural Network

51%

Peng J. , Zhang D. , Liao X.

Fundamenta Informaticae

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2009

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tom Vol. 90, nr 3

269-282

EN

Using Chaotic characteristics of dynamic system is a promising direction to design cryptosystems that play a pivotal role in a very important engineering application of cognitive informatics, i.e., information assurance and security. However, encryption algorithms based on the lowdimensional chaotic maps face a potential risk of the keystream being reconstructed via return map technique or neural network method. In this paper, we propose a new digital image encryption algorithm that employs a hyper-chaotic cellular neural network. To substantiate its security characteristics, we conduct the following security analyses of the proposed algorithm: key space analysis, sensitivity analysis, information entropy analysis and correlation coefficients analysis of adjacent pixels. The results demonstrate that the proposed encryption algorithm has desirable security properties and can be deployed as a cornerstone in a sound security cryptosystem. The comparison of the proposed algorithm with five other chaos-based image encryption algorithms indicates that our algorithm has a better security performance.

6

Investigation of the Acoustical Environment of the Elderly’s Living Place

51%

Zeng Y. , Peng J. , Zhao L.

Archives of Acoustics

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2018

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tom Vol. 43, No. 3

531--536

EN

A questionnaire survey was conducted in the residential quarters of Guangzhou, for which 582 elderly people over 60 years old were randomly recruited. The hearing impairment of the participants was evaluated using the Hearing Handicap Inventory for the Elderly (HHIE). The participants’ subjective responses to the acoustical environment of their living place and the impact of the living acoustical environment (LAE) on the participants were investigated. The results show that the participants with a low HHIE score and no hearing impairment evaluated their LAE more favourably, and they considered that the effect of the LAE on their daily life was weak. However, those with a high HHIE score and severe hearing impairment evaluated their LAE poorly, and considered its effect on their daily lives to be significant. For the elderly, the worse the hearing is, the higher their demand for a better LAE. Traffic noise, construction noise, noise from residential quarters, and noise from next door or upstairs neighbours were the main noise sources in the elderly’s living places, and traffic noise, construction noise, and noise from next door and upstairs were the most influential sources. 28.9% of the respondents had trouble hearing what their family said in their living place. The elderly without hearing impairment considered that continuous noise was the main reason that they could not hear what their family said in their living place, while those with hearing impairment believed that their own hearing problem was a contributing factor.

7

Identification of Ship Maneuvering Model Using Extended Kalman Filters

51%

Shi C. , Zhao D. , Peng J. , Shen C.

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

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2009

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tom Vol. 3, no. 1

105--110

EN

Ship maneuvering models are the keys to the research of ship maneuverability, design of ship motion control system and development of ship handling simulators. For various frames of ship maneuvering models, determining the parameters of the models is always a tedious task. System identification theory can be used to establish system mathematical models by the system’s input data and output data. In this paper, based on the analysis of ship hydrodynamics, a nonlinear model frame of ship maneuvering is established. System identification theory is employed to estimate the parameters of the model. An algorithm based on the extended Kalman filter theory is proposed to calculate the parameters. In order to gain the system’s input and output data, which is necessary for the parameters identification experiment, turning circle tests and Zig-zag tests are performed on shiphandling simulator and the initial data is collected. Based on the Fixed Interval Kalman Smoothing algorithm, a pre-processing algorithm is proposed to process the raw data of the tests. With this algorithm, the errors introduced during the measurement process are eliminated. Parameters identification experiments are designed to estimate the model parameters, and the ship maneuvering model parameters estimation algorithm is extended to modify the parameters being estimated. Then the model parameters and the ship maneuvering model are determined. Simulation validation was carried out to simulate the ship maneuverability. Comparisons have been made to the simulated data and measured data. The results show that the ship maneuvering model determined by our approach can seasonably reflect the actual motion of ship, and the parameter estimation procedure and algorithms are effective.

8

Reverse circulation DTH hammer drilling technology

51%

Yin K. , Bo K. , Peng J. , Fan L.

Zeszyty Naukowe. Górnictwo / Politechnika Śląska

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2009

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tom z. 287

289-297

EN

The technical characteristics and operational principal of the reverse circulation DTH hammer drilling technology is introduced in this paper. It is that with the computerized emulation and the simulation technique to assist the drilling tool design, so the optimum designed DTH hammer gets stable performance, and the drilling bit is with good reverse-circulation ability, and further more, it has already developed serialization products. The reverse circulation DTH hammer drilling technology has been fully applied in areas such as the geological exploration core in complex formation, hydrological drilling wells, and large diameter rock embedding piles drilling in hard rock, and obviously, it is achieved favourable economic and social benefits.

PL

W artykule scharakteryzowano technologię wiercenia z cyrkulacją zwrotną. Urządzenie DTH zapewnia dobrą wydajność, co decyduje o jego znaczeniu ekonomicznym. Wiercenia ze zwrotną cyrkulacją są stosowane w poszukiwaniach geologicznych (z rdzeniowaniem) w formacjach o złożonej budowie, w przypadku studni, odwiertów wielkośrednicowych, a także dla skał o dużej twardości.

9

A PSBM model for environmental efficiency evaluation and its application

51%

Song M. , Peng J. , Liu W. , An Q.

Polish Journal of Environmental Studies

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2014

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tom 23

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nr 3

EN

The traditional efficiency evaluation model considering undesirable outputs is only able to calculate the efficiency of the overall value of the decision-making units. This paper puts forward a new environmental efficiency evaluation based on the proper slack-based measurement (PSBM) model, which can give the efficiency values of the inputs, desirable outputs, and undesirable outputs. The results from the new model are not only highly correlated with SBM-based evaluation results, but also coincide with reality, which can be used to test the effectiveness of the new model. Our model provides more information for environmental efficiency evaluation analysis.

10

Electrochemical Behavior of Ascorbic Acid and Uric Acid in the Presence of Micelles and Their Selective Determination Application

51%

Gao Z. , Peng J. , Han X.

Polish Journal of Chemistry

|

2007

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tom Vol. 81, nr 3

441-454

EN

The electrochemical behavior of ascorbic acid (AA) and uric acid (UA) in both aqueous cetylpyridinium bromide (CPB) and sodium dodecyl benzene sulfonate (SDBS) micellar solutions have been studied by cyclic voltammetry. The oxidation peak potentials shift more negatively, and the peak currents increase in aqueous CPB micellar solutions for AA and UA. However, the oxidation peak potentials shift more positively, and the peak currents decrease in aqueous SDBS micellar solutions for AA and UA. Therefore, CPB can enhance the electrochemical oxidation reaction for AA and UA, and SDBS hinders the electrochemical oxidation reaction. The electrochemical kinetic parameters for AA and UA in both aqueous CPB and SDBS micellar solutions are determined by chronocoulometry (CC) and chronoamperometry (CA). The charge transfer coefficients _ and the electrode reaction rate constants kf for AA and UA are enhanced in aqueous CPB micellar solutions, but reduced in aqueous SDBS micellar solutions. The pulse differential voltammetric behavior for AAand UAare also investigated in this work. The experimental results show that the oxidation peak potentials forAAandUAare separated by 270mVin the presence ofCPB in aqueous PBS (phosphate buffer solution, pH 6.8) solutions. Thus, AA and UA can be selectively determined in aqueous CPB micellar solutions, especially selectively determination of UA in the presence of excess of AA is possible. According to our work, the practical application of the results can be used to determineUAin human urine and serum samples, the determination results are satisfied.

11

An Empirical Model for the Ionospheric Global Electron Content Storm-Time Response

51%

Li S. , Galas R. , Ewert D. , Peng J.

Acta Geophysica

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2016

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tom Vol. 64, no. 1

253--269

EN

By analyzing the variations of global electron content (GEC) during geomagnetic storm events, the ratio “GEC/GECQT” is found to be closely correlated with geomagnetic Kp index and time weighted Dst index, where GECQT is the quiet time reference value. Moreover, the GEC/GECQT will decrease with the increase of the solar flux F10.7 index. Furthermore, we construct a linear model for storm-time response of GEC. Eighty-two storm events during 1999-2011 were utilized to calculate the model coefficients, and the performance of the model was tested using data of 8 storm events in 2012 by comparing the outputs of the model with the observed GEC values. Results suggest that the model can capture the characteristics of the GEC variation in response to magnetic storms. The component describing the solar activity influence shows a counteracting effect with the geomagnetic activity component; and the influence of Kp index causes an increase of GEC, while the time weighted Dst index causes a decrease of GEC.

12

Effects of modified atmosphere package on preservation of strawberries

51%

Zhang M. , Xiao G. , Peng J. , Salokhe V. M.

International Agrophysics

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2003

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tom 17

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nr 3

13

Effect of pre-freezing treatment methods on the quality retention of thawed areca fruit

51%

Zhang M. , Duan Z. , Zhang J. , Peng J.

International Agrophysics

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2003

|

tom 17

|

nr 4

14

Estimating the number of components in an OSL decay curve using the Bayesian Information Criterion

45%

Peng J. , Dong Z. , Han F. , Han Y. , Dai X.

Geochronometria

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2014

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tom Vol. 41, no. 4

334--341

EN

The optically stimulated luminescence (OSL) decay curve is assumed to consist of a number of first-order exponential components. Improper estimation of the number of components leads to under-or over-fitting of the curve under consideration. Hence, correct estimation of the number of components is important to accurately analyze an OSL decay curve. In this study, we investigated the possibility of using the Bayesian Information Criterion to estimate the optimal number of components in an OSL decay curve. We tested the reliability of this method using several hundred measured decay curves and three simulation scenarios. Our results demonstrate that the quality of the identification can be influenced by several factors: the measurement time and the number of channels; the variability of the decay constants; and the signal-to-noise ratios of a decaying component. The results also suggest that the Bayesian Information Criterion has great potential to estimate the number of components in an OSL decay curve with a moderate to high signal-to-noise ratio.

15

Effect of coating treatments on the extension of the shelf-life of minimally processed cucumber

45%

Zhang M. , Xiao G. , Luo G. , Peng J. , Salokhe V. M.

International Agrophysics

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2004

|

tom 18

|

nr 1

16

Antifungal activity and physicochemical properties of a novel antimicrobial protein AMP-17 from Musca domestica

38%

Yang L.-B. , Guo G. , Su P.-P. , Fu P. , Peng J. , Xiu J.-F. , Li B.-Y.

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tom 68

|

nr 3

17

Contrasting patterns of sun-red and shade-green leaves of Buxus microphylla in response to gradients of excess light during winter acclimation

38%

Peng J. , Jiang X. , Jia M. , Guo L. , Gao R. , Liu Y.

Acta Physiologiae Plantarum

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2016

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tom 38

|

nr 10

18

Comparative analysis of three ionospheric broadcast models for global navigation satellite systems

38%

Li S. , Li L. , Wang S. , Peng J. , Xu Y. , Zhao Y.

Acta Geophysica

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2017

|

tom Vol. 65, no. 2

395--410

EN

An ionospheric model and corresponding coefficients broadcasted via GNSS navigation message are generally used to estimate the time delay for single-frequency GNSS users. In this article, the capabilities of three ionospheric models, namely, Klobuchar model, NeQuick Galileo version (NeQuick G), and Neustrelitz TEC broadcast model (NTCM-BC), were assessed. The models were examined in two aspects: total electron content (TEC) prediction and ionospheric delay correction effects in single-point positioning. Results show that both NeQuick G and NTCM-BC models outperformed Klobuchar model for predicting global TEC values during all the test days. Compared with Slant TEC (STEC) along the receiver-to-satellite ray path derived from IGS global ionosphere map (GIMs), STEC from NeQuick G and NTCM-BC models tend to have less bias than those from Klobuchar model in most situations. The point positioning results were improved by applying ionospheric broadcast models especially at the mid- and low-latitude stations.

19

Repeated isoflurane exposures of neonatal rats contribute to cognitive dysfunction in juvenile animals: the role of miR-497 in isoflurane-induced neurotoxicity

38%

Que Y. , Zhang F. , Peng J. , Zhang Z. , Zhang D. , He M.

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nr 2

20

Using an Interdigital Micromixer for Separation of In3+ from Zinc Hydrometallurgical Process with D2EHPA as an Extractant

38%

Li C. , Jiang F. , Ju S. , Peng J. , Wei Y. , Zhang L.

Archives of Metallurgy and Materials

|

2017

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tom Vol. 62, iss. 2A

873--878

EN

Experiments were performed in an interdigital micromixer with 30 microchannels (40 μm width of each channel) to separate In3+, Fe3+ and Zn2+ from sulfate solutions using Di-(2-ethylhexyl)phosphoric acid (D2EHPA) as the extractant. The effects of pH, extractant concentration and flow rate on the extraction efficiency and flow rate on mass transfer coefficient of In3+, Fe3+ and Zn2+ were investigated. At a phase flow rate of 7.0 mL/min and initial solution pH of 0.423, the extraction efficiency of In3+, Fe3+ and Zn2+ was 99.29%, 3.43% and 2.54%, respectively and mass transfer coefficient of In3+, Fe3+ and Zn2+ was 144.307 s-1,1.018 s-1 and 0.750 s-1. Then, the loaded organic phase was stripped in an interdigital micromixer. At a phase flow rate of 9.0 mL/min and HCl concentration of 160 g/L, stripping efficiency of In3+ was 98.92% and mass transfer coefficient of In3+ was 169.808 s-1, while concentration of Fe3+ and Zn2+ was lower than 0.005 g/L with good separation of In3+ from Fe3+ and Zn2+.