Hu S.,Maoming College |
Fu G.,Guangzhou University |
Chen H.,Maoming College
Yadian Yu Shengguang/Piezoelectrics and Acoustooptics | Year: 2010
The microstructure and humidity-sensitive characteristics of SnO2-LiZnVO4 system humidity-sensitive ceramics were studied by comparing the method of urea co-precipitation with the method of ammonia co-precipitation. The influence of the amount of liquid-doped LiZnVO4 on the humidity-sensitive characteristics was researched. The experimental results showed that the SnO2-LiZnVO4 system humidity-sensitive material prepared by the co-precipitation with urea and ammonia were characterized by the rod and ball shaped grains respectively. Humidity-sensitive characteristics indicated that humidity-sensitive characteristics of the material is best with 10% liquid-doped LiZnVO4 in the both co-precipitation SnO2 powders. But the material with rod shaped grains characterized lower resistance at lower humidity and with proper humidity sensitivity than that with ball grain. The characteristics of frequencies showed that the material with rod and ball grain both have better respond to frequencies. The characteristics of stabilizations showed that the sample with rod shaped grains was more stationary than that with ball shaped grains.
Hu S.,Maoming College |
Fu G.,Guangzhou University
Sensors and Actuators, A: Physical | Year: 2010
Ceramic humidity sensitive samples composed of the SnO2- LiZnVO4 system were synthesized in liquid state and characterized by SEM. Compared with the sample synthesized in conventional solid-state reaction, the sample synthesized in liquid state has the advantages of lower impedance in the low relatively humidity (RH) range and better impedance-RH linearity. The effect of different levels of liquid-state doping of LiZnVO4 on the humidity-sensitive characteristics was studied. It was found that humidity-sensitive characteristics and microstructure can be improved by controlling the level of liquid-doped LiZnVO4. The best results were obtained with the 10 mol% LiZnVO4-doped sample, which exhibited excellent linearity in the humidity range of 11-93% RH. An impedance variation of more than four orders of magnitude, better impedance-RH linearity, high BET surface area, a narrow hysteresis loop, and rapid response were obtained. SEM micrographs of the grain structures and complex impedance analysis confirm that high performance of the sensitive layer is associated with a fine microstructure morphology, which is characterized by suitable rod shaped grains forming mesopores and by well-distributed LiZnVO4 additives, forming a thin glassy surface covering. © 2010 Elsevier B.V. All rights reserved.
Chen H.-B.,Maoming College |
Hu S.-M.,Maoming College |
Gao Y.-J.,Guangxi University
Faguang Xuebao/Chinese Journal of Luminescence | Year: 2010
By using the method of optical transfer maxtrix, the optical transmission properties of compound photonic crystal with two symmetrical defect layer at the two ports were studied. The investigation results showed that two resonance transmittance peaks exist in the band gap in dual-period photonic crystal [D(AB)mD]2 structure. The resonance transmittance peaks will shift with the small changes of the dielectric constants of photonic crystal induced by a control light. The more the dielectric constants change, the more resonance transmittance peaks shift, leading to high-efficiency dual channeled optical switches being realized. Each resonance transmission peak can split into N - 1 different transmission peaks in the [ D( AB)m D]N structure photonic crystal. We can gain appropriate multiple channel filters and optical switches by adjusting N.
Chen H.,Maoming College |
Hu S.,Maoming College |
Gao Y.,Guangxi University
Bandaoti Guangdian/Semiconductor Optoelectronics | Year: 2010
Resonance transmission spectra in dual-periodical photonic quantum-well structure is studied by using the transfer matrix method, and its regularity is analyzed. It is found that the band gap is widen and several resonance transmission spectra appear in the band gap. The number of resonance transmission spectra in the barrier band frequency is related to the period of the barrier region, and that in the well band frequency is related to the period of the well region. It is also indicated that each transimission spectrum will split into N-1 different frequencies when the periods of barrier and well regions are tuned, where N is the period of the dual-periodical photonic quantum-well structure. These split spectra are un-folded mutually. In this way, photonic confined states can be increased multiplicatively within the forbidden band gap region and the density of signal channel can be increased, optimizing the effective bandwidth. It may be applied widely in the fields of superdense wavelength division multiplexing for optical communication and precise optical measurements.
Liu J.,Zhejiang University |
Liu J.,Maoming College |
Ren Y.,Zhejiang University |
Yao S.,Zhejiang University
Chinese Journal of Chemical Engineering | Year: 2010
In general, productions of natural pigment in submerged microorganism culture were much less than that in solid-state fermentation, because the solid-state culture can provide a support carrier for the mycelium. To~improve~natural~pigment~production, the cultivation of Monascus purpureus in submerged encapsulated cell was investigated. Monascus purpureus immobilized in polyelectrolyte complex (PEC) microcapsules, which were prepared by sodium cellulose sulphate (NaCS) and poly-dimethyl-diallyl-ammonium chloride (PDMDAAC), was a good substitute for submerged cell culture because it mimicked the solid-state environment. The repeated-batch process with encapsulated cells was studied in flasks and a bubble column. The results indicated that the bubble column was more suitable for the encapsulation culture than the shaking flasks because of its good mass transfer performance and minor shear stress on cells. Owing to the protection of the microcapsule's membrane, Monascus purpureus in microcapsules increased approximately three times over that in free cell culture with negligible cell leakage to the medium. The pigment production in the bubble column finally reached 3.82 (OD 500), which was two times higher than in free cell culture. In addition, the duration of each batch was shortened to 15 of that in free cell culture. © 2010 Chemical Industry and Engineering Society of China (CIESC) and Chemical Industry Press (CIP).
Zhang J.,Maoming College
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2010
A multi-line with redundant term location-driven algorithm and scheme of implementation circuit applied to LCD driver chips is presented in this paper. The multi-line location-driven algorithm reduces the number of column driver voltage level by the method of increasing the redundant column in modulation matrix and redundant data in display data matrix. In addition, implementation circuit of the algorithm is proposed. The experimental results show that the algorithm can reduce 30% power consumption and achieve higher integrity in LCD display driver chip.
Xie S.-L.,South China University of Technology |
Sun G.-X.,South China University of Technology |
Xiao M.,South China University of Technology |
Xiao M.,Maoming College |
And 2 more authors.
Tien Tzu Hsueh Pao/Acta Electronica Sinica | Year: 2010
Two-step strategy has become a fundamental method for underdetermined blind signal separation and the estimation of mixing matrix is a prerequisite for the source's recovery. This paper proposes a two-step blind source extraction method for incompletely sparse case. The approach firstly estimates the basis vectors (columns of matrix) of partial sources using single-source intervals and then extracts the corresponding sources with minimum interference;it doesn't depend on other basis vector except the corresponding basis vector, so it avoids the essential condition the matrix is recoverable. Several simulation experimental results demonstrate its performance and practices.
Lin P.,Maoming College |
Jie Y.,Maoming College |
Mo G.,Maoming College
Natural Gas Industry | Year: 2010
The storage stability of the diesel No. 0 mixed with the biodiesel prepared using different raw materials, i.e., hogwash, lard, palm, and peanut oils, was studied by different proportions. The acid value, kinematic viscosity, and storage invariability of this mixed diesel after different time of storage were determined. The stability of biodiesel was lower than the diesel No. 0, and the prepared biodiesel with hogwash oil had the lowest stability among the prepared biodiesel with different raw materials. When the prepared biodiesel was mixed with the diesel No. 0, the proportion of the prepared biodiesel was larger, and the stability of the mixed fuel oil was lower, especially with the hogwash oil as raw materials. The proportion of biodiesel should be ≯ 50%, and the storage time should be < 80 days.
Chen K.,Maoming College |
Ke W.-D.,Maoming College |
Peng Z.-P.,Maoming College
Journal of Harbin Institute of Technology (New Series) | Year: 2010
A cooperative shooting method based on robot soccer by colliding to improve velocity is studied. The collision between two robots in an angle produced the momentum to improve the velocity of ball and an appropriate angle was set to shoot, which made the success rate be improved greatly. Finally the validity and feasibility of this method had been proved through the simulating experiments.
Li Q.-X.,Maoming College
3CA 2010 - 2010 International Symposium on Computer, Communication, Control and Automation | Year: 2010
Accuracy of single filter used in most of vehicle navigation decreases when system state is both linear and nonlinear. According to the output state of the receiver to choose linear or nonlinear filter, a kind of combined filtering structure is proposed. Furthermore, a derivative- free filter is adopted as nonlinear filter, especially, formulas of state and random noise covariance matrix's Cholesky decomposition update are improved, which guarantees positive definiteness of covariance matrix and its square root; Due to high precision and robust performance of linear Kalman filter on linear filtering, it's filtering equations are improved to eliminate positioning error caused by velocity error; The advantages of two filters are verified in static and dynamic process respectively by simulation experiment. Finally, vehicle simulation results show that the combined linear- nonlinear filter has low error and computation cost, is better than single filter. © 2010 IEEE.