Time filter

Source Type

Tang Y.,Chengdu University of Technology | Zhang F.,Henan economics and Trade Vocational College | Guo Y.,Chengdu University of Technology
Chinese Journal of Sensors and Actuators | Year: 2010

Aiming at mobile robots, the ultrasonic distance-measuring sensor is researched based on microcomputer AT89C51 as control system, and achieve the development of hardware/software. The system formation, experiment result and system error is analyzed. The system can measure certain distance on the premise that the speed of reflected wave in the air. Results show that the design is able to improve obstacle avoidance capabilities and the precision and reliability at mobile robot navigation. Source

Zhang C.-T.,Henan economics and Trade Vocational College | Zhao A.-X.,Xian University of Science and Technology
IEEE Region 10 Annual International Conference, Proceedings/TENCON | Year: 2013

The BP network uses the rule of local decline to slow convergence speed and easy to fall into local optimum. With the increase of BP input parameters lead to the dimension disaster. Taking into consideration the above problems, Using adaptive ant colony optimization algorithm optimized the training process of BP network referred to as AACOABP. The BP network and the BP network optimized by adaptive ant colony algorithm to (AACOABP) were used to identify the faulty type of the collecting samples about DGA fault test data, AACOABP can make the fault identification accuracy is greatly increased, the recognition accuracy from 50% ∼ 75% to 87.5% ∼ 100%. © 2013 IEEE. Source

Yang D.,North China University of Water Conservancy and Electric Power | Li X.,Henan economics and Trade Vocational College | Liu Y.,Henan Normal University
Journal of Cluster Science | Year: 2013

The time-dependent density functional theory (TDDFT) method has been carried out to study the influences of hydrogen bonding and solvent polarity on the spectral properties of 4-aminophthalimide (4AP) clusters formed with hydrogen-accepting solvents triethylamine (TEA) and dimethyl sulfoxide (DMSO). The ground- and S1-state geometry structure optimizations, hydrogen bond energies, absorption and emission spectra for both the 4AP monomer and its two triply hydrogen-bonded clusters 4AP + (TEA)3 and 4AP + (DMSO)3 have been calculated using DFT and TDDFT methods respectively with the hybrid exchange correlation functional PBE1PBE and split-valence basis set 6-311++G(d,p). It has been demonstrated that the two hydrogen bonds I and II formed with the amine group of 4AP are significantly strengthened while the hydrogen bond III formed with the imide group is slightly weakened due to the intramolecular charge transfer from the amine group to the two carbonyl groups of the 4AP molecule upon photoexcitation. In addition, the hydrogen bonds formed by 4AP with DMSO are stronger than those formed with TEA, which together with its strong polarity, should be the main reasons for the more redshifts of both the absorption and the fluorescence spectra of 4AP in solvent DMSO than those in TEA. © 2013 Springer Science+Business Media New York. Source

Qin Z.,North China University of Water Conservancy and Electric Power | Li X.,Henan economics and Trade Vocational College | Zhou M.,Henan economics and Trade Vocational College
Journal of the Chinese Chemical Society | Year: 2014

The intermolecular hydrogen-bonds between proflavine cation (PC) and water molecules are investigated by density functional theory (DFT) and time-dependent density functional theory (TDDFT) methods. The ground-state geometry optimizations, electronic excitation energies and corresponding oscillation strengths of the low-lying electronically excited states for the isolated proflavine cation, the hydrogen-bonded PC-H2O dimer and PC-(H2O)2 trimer are calculated. Intermolecular hydrogen bonds at the central site of proflavine molecule are found to be stronger than the peripheral site. The hydrogen bond N-H×××O for the hydrogen-bonded dimer are indicated to be weakened in the excited states, since the excitation energy is increased slightly comparing to the monomer. Hydrogen bonds of PC-(H2O)2 trimer with the same type as the dimer are strengthened in the excited state, which is demonstrated by the decrease of the excited energies. Thus, hydrogen bond strengthening and weakening are observed to reveal site dependent feature in proflavine molecule. Furthermore, the hydrogen bond at central site induces the blue-shift of the absorption spectrum, while the ones at peripheral site induce red-shift. Hydrogen bonds with the same type at peripheral and central sites of proflavine molecule provide different effects on the photochemical and photophysical properties of proflavine. © 2014 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, Germany. Source

Li Y.-Q.,Henan economics and Trade Vocational College | Zhang C.-T.,Henan economics and Trade Vocational College
Applied Mechanics and Materials | Year: 2013

In order to improve the performance of the query optimization for the distribute database, an improved query optimization algorithm was proposed based on the genetic algorithm. The query execution cost model based on the genetic algorithm was proposed in this paper. The distributed database was emerged in the 70's of the last century and developed with the progress of the computer technology and network technology, the distributed database was the database system which is distributed storage dispersedly in physics and with centralized processing in mathematic logic. Because the storage points were not uniform, the structure of the distributed database is much more complicated than the centralized database. Both the genetic algorithm and the dynamic exhaustive planning algorithm were taken in the query simulation for the performance comparison. The result shows that the genetic query optimization method in this paper has better performance in the distributed database query application. The case study and the simulation result show that the algorithm can get a satisfactory optimization result in a few iterations and the query optimization algorithm based on the genetic method has nice performance of the query optimization property, and the consumption and costs of the query is reduced to the minimum. The method which this paper proposed has good application performance and is valuable to put into practice. © (2013) Trans Tech Publications, Switzerland. Source

Discover hidden collaborations