Editor in chief：朱立光
International standard number：ISSN 1008-1542
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2011, 32(4):303-307. DOI: 10.7535/hbkd.2011yx04001
Abstract:As 1≤k≤n-1, by using the fixed-point theorem of cone expansion and compress, the existence of positive solutions to a system of singular (k, n-k) conjugate multi-point boundary value problems is studied.
2011, 32(4):308-312,325. DOI: 10.7535/hbkd.2011yx04002
Abstract:Adding a extended Hubbard term to the SSH model for polyacetylene, we carried a self-consistent variation calculation on biexciton and two single-excitons in polyacetylene. The configuration,energy level, charge density wave, spin density wave and absorbance in the two systems are compared. Results show that the two single-excitons can not exist stablely without electronic correlation; radiuses of biexitons and single-excitons decrease as the electronic correlation increases；two single-excitons system has four energy levels in the energy gap, while biexciton system has only two；charge density wave, spin density wave and absorbance of the two systems all change according to the electronic correlation and with marked differences. The facts offer a criterion to distinguish the two kinds of exciton, and show that the electronic correlation must be considered in excitons behavior.
2011, 32(4):313-315,402. DOI: 10.7535/hbkd.2011yx04003
Abstract:In this paper, a new simple-calculating estimation method based on two new matrices are obtained by using the Frobenius inequality. Therefore a convergence sequence of lower bounds and upper bounds of the perron root can be constructed.Some examples are given to show the effectiveness of the new method is effective.
2011, 32(4):316-320,396. DOI: 10.7535/hbkd.2011yx04004
Abstract:The cross-linked copolymerization reactions of acrylamide, crylic acid and polyethyleneglycol macromonomer were carried out in the reverse emulsion system. Influencing factors as emulsifier, initiator and temperature were investigated. The morphology of the cross-link polymers were determined by TEM. The results showed diameter of cross-linked polymer particles are several hundred nanometers and the solid content can reach 25%.
2011, 32(4):321-325. DOI: 10.7535/hbkd.2011yx04005
Abstract:Due to the uncertainty of the steel wall intrinsic pressure vessel initial static intensity and the loads, based on the application of information entropy theory, the relationship of the safety factor, the test pressure coefficient and the reliable index were analyzed. The research indicates that:1) For cylinder vessel, the yield safety factor should be no less than 1.50and the burst safety factor no less than 1.90; for spherical vessel or spherical head, the yield safety factor should be no less than 1.40and the burst safety factor no less than 2.15; for flat ribbon-wound pressure vessel, the yield safe factor should be no less than 1.45and the burst safety factor no less than 2.40; for super-high pressure thick wall cylinder, the burst safety factor should be no less than 2.55. 2) The test pressure coefficient of steel wall intrinsic pressure vessel should be no less than 1.07under barometrical and hydraulic pressure tests. 3) The test pressure coefficient of cylinder should not be greater than 1.20for barometrical pressure tests, and not greater than 1.35for hydraulic pressure tests; the test pressure coefficient of spherical vessel should not be greater than 1.18for barometrical pressure tests, and not greater than 1.32for hydraulic pressure tests; the test pressure coefficient of flat ribbon-wound pressure vessel should be not greater than 1.24for barometrical pressure tests, 收稿日期:2011-01-01；修回日期:2011-03-29；责任编辑:冯 民 基金项目:武汉市教育局重点科研项目(2008K027)；武汉市创新人才开发资金重大创新专项资助项目 作者简介:刘小宁(1963-),男,湖北武汉人,教授,教授级高级工程师,主要从事机械结构、压力容器可靠性等方面的教学和研究。and not greater than 1.41for hydraulic pressure tests; the test pressure coefficient of super-high pressure thick wall cylinder should not be greater than 1.66for hydraulic pressure tests.
2011, 32(4):326-329. DOI: 10.7535/hbkd.2011yx04006
Abstract:In view of the working effect expectation and the dynamic performance of the feeler mechanism, optimization design of the qualities and forms of members in mechanisms is implemented to reduce inertial force. Optimal computational model is designed and optimization design goal function is determined.
2011, 32(4):330-332,350. DOI: 10.7535/hbkd.2011yx04007
Abstract:Cylindrical involute helical gear has complex tooth profile, so it is difficult to conduct parameterized design. 3D software UG-NX6is introduced to conduct 3D modeling for cylindrical involute helical gear. By this modeling method,the figure of corresponding cylindrical involute helical gear can be obtained immediately after changing the parameters. The method provides a reference for parameterized design of other bodies with complex surface profile.
2011, 32(4):333-337. DOI: 10.7535/hbkd.2011yx04008
Abstract:By using LED light source, super capacitor, infrared detector and photodetector and with commercial power as standby power supply, a solar corridor lighting system is put forward. Taking a 6-storey building for example, the paper puts forward the design of the illumination light source, detector, optimum tilted angle of solar panel, capacity of solar cells, capacity of super capacitor and system controller. Meanwhile, the number and parameters of selected devices is listed. At last, the paper analyzes the economic benefit of the system.
2011, 32(4):338-341. DOI: 10.7535/hbkd.2011yx04009
Abstract:Based on the analysis of the mechanism of exploring coil detecting turn-to-turn short circuit of rotor winding, fault diagnosis system is designed. Based on WTMM, the signal is analyzed and the Lipschitz index of wave characteristics is calculated. With MATLAB as the background to simulate the signals and the variance of Lipschitz index as calibration, the fault location and degree of the turn-to-turn short circuit can be determined. The experiment shows that determining the fault and the fault degree by means of Lipschitz index is reliable and easy.
2011, 32(4):342-346. DOI: 10.7535/hbkd.2011yx04010
Abstract:This paper proposed a source number estimation algorithm based on support vector machine (SVM) for improving estimation performance in low ratio of signal to noise, small snapshots and color noise environment. This algorithm decomposes the received signal data covariance matrix to get the signal vector and the noise vector at first, and then abstracts the property sort of signal and noise with Gerschgorin circle algorithm by the orthotropic property of the antenna array manifold and the noise vectors. At last, the algorithm constructs and trains the SVM to get the number of the incidence signals. The paper compares the algorithm with some classic algorithms by simulation experiment in low ratio of signal to noise, small snapshots and color noise environment, and results show that the algorithm has higher precision than that of classic algorithms.
2011, 32(4):347-350. DOI: 10.7535/hbkd.2011yx04011
Abstract:This paper presents a target spatialization algorithm based on a two-dimensional image, without knowing the parameters of the camera. It is on the basis of four coplanar lines on the object matching with their perspective image. The basic steps include image preprocessing, edge detection by using Prewitt operator, determination of the image region based on contour feature and the topological relations, demarcation of the parameters of the camera and realization of the two-dimensional spatial location. Experimental results show that the method is faster and has higher precision.
2011, 32(4):351-354,372. DOI: 10.7535/hbkd.2011yx04012
Abstract:This paper proposes an algorithm based on hash table for dynamic vector dimension-reduction. The proposed algorithm uses hash table as data structure of characteristic vector so as to reduce the step of constructing vector template. This can realize dynamic vector reduced-order of high dimensional times sparse vector, and effectively reduce the computation of data classification algorithm so as to improve the capability of classifier.
2011, 32(4):355-358,390. DOI: 10.7535/hbkd.2011yx04013
Abstract:In order to improve the precision of meta search engine, an improved results merging algorithm based on PageRank is proposed. With meta search engine technology analyzed and the disadvantages of PageRank algorithm considered, rtf algorithm is proposed. The improved merging algorithm could realize query based on synonym or near-synonym. It use in the professional search engine of coal geology, proves to be effective.
2011, 32(4):359-363. DOI: 10.7535/hbkd.2011yx04014
Abstract:Crystallization is an important method to purify substances and is widely applied in pharmacy and chemical industries. Penicillin crystallization is a complicated process with variable time, uncertainy and multi-variables. The requirement of control in different stages is variable and there is some coupling between temperature and liquid level control in the tank. Traditional PID control is difficult in attaining better control effect. In response to this complex project, this paper proposed fuzzy robust control methods. First the coupling in penicillin crystallization process is eliminated by series decoupling compensator. Then T-S fuzzy model of the system is constructed. H∞ robust control method is used in T-S fuzzy model. Simulation results show that state feedback H∞ controller can control the system effectively, showing that the whole system has better robustness. It offers reference for practical penicillin crystallization.
2011, 32(4):364-367. DOI: 10.7535/hbkd.2011yx04015
Abstract:Common similarity computing methods are analyzed and the shortcomings are pointed out. In order to meet the needs of practical applications, a similarity computing method of higher accuracy is designed based on the semantics of statements and the important level of words in the sentence. The effectiveness of this approach is proved by the experiment.
2011, 32(4):368-372. DOI: 10.7535/hbkd.2011yx04016
Abstract:In this paper, a multi-region contour tracking algorithm is presented for yarn hairiness feature extraction. Based on chain code contour tracking, the algorithm adjusts track direction and fills the tracked yarn region. The experiment shows that the algorithm has nothing to do with the number of yarns, and its continuous closed boundary curve is only one pixel wide, which improves the extraction efficiency and accuracy.
2011, 32(4):373-379. DOI: 10.7535/hbkd.2011yx04017
Abstract:Based on minimized Gibbs energy, a simulation model for biomass combustion is developed which focuses on K, Na migration, while experiment under condition of high temperature and high pressure is predicted. The result shows that temperature is the mostly important influencing factor in the operation conditions. Along with the increasing temperature, gaseous alkali concentration increases. When temperature increases to 1000℃, 8.98% K and 6.05% Na release from the raw meteral into gas. When temperature increases to 1400℃, 96.6% K and 92.2% Na release from the raw meteral into gas. In the gas, mostly are alkali metal chlorides and seldom is alkali metal sulfate. When pressure is increased, the concentration of gaseous K and Na begin to decrease, the amount of solid-state K and Na increases.
2011, 32(4):380-383. DOI: 10.7535/hbkd.2011yx04018
Abstract:In this article, the mechanism model of Cu-CMP is studied. A kind of slurry is excogitated, which uses colloidal silica with diameter of 40nm as abrasives, hydrogen peroxide as oxidant, organic alkali as pH modulator and chelating agent, FA/O as surfactant. The influences of process conditions, including pressure, flow rate, rotary speed and temperature, etc., and polish slurry(H2O2, organic alkali, abrasive particle) on copper polishing rate are investigated. Based on these resuls, the appropriate process conditions and the polish slurry are determined to resolve the dishing that exists in Cu-CMP, and the influence of surfactant on surface roughness is analyzed.
2011, 32(4):384-390. DOI: 10.7535/hbkd.2011yx04019
Abstract:With pure water as solvent, essential oil is extracted from chestnut flower by using the method of Accelerated Solvent Extraction, and is directly analyzed by purge and trap technique. Essential oil of chestnut flower is extracted by steam distillation method and the distillation liquid is analyzed by GC-MS. The results show that essential oil of chestnut flower contains twenty eight components including ten kinds of esters, four kinds of alcohols and nine kinds of aldehydes. The main volatile components of chestnut flower essential oil, as well as the main components of the chestnut floral aroma, are alcohols, aldehydes and esters. The experiments show that the best condition for producing Freshener is as follows:the late chestnut flower as raw materials, pressure of 0.04MPa,distillation time of 2.5h and liquid to solid ratio of 6.
2011, 32(4):391-396. DOI: 10.7535/hbkd.2011yx04020
Abstract:Polysulfone and meta-aramid fibers were blended to spin yarns on domestic equipment. The results show that blending ratio has some effect on yarn evenness. Polysulfone and meta-aramid blended yarn evenness gets better with the increasing polysulfone blending ratio. It results from the decrease of additional unevenness caused by the difference of the fibers friction property. Fiber linear density unevenness and the number of fibers have little effect on yarn evenness. When polysulfone and Meta-aramid blended yarn breaks, slippage occurs considerably, while yarn breaking strength and breaking elongation change slightly. The number of fibers in the section of the blended yarn varies with blending ratio. Yarn hairiness decreases when polysulfone blending ratio increases. Borda method was used to analyze the blended yarn quality. It shows that when the polysulfone ratio is 80percent, the blended yarn quality is the best.
2011, 32(4):397-402. DOI: 10.7535/hbkd.2011yx04021
Abstract:In this paper, the feasibility of UASB-SBBR treatment of amino acid production wastewater pretreated by electrolytic treatment was studied. The experiments show that during the UASB start-up phase, if highly activated granular sludge is inoculated and the influent COD is controll properly, and after a period of domesticating, anaerobic granular sludge can be used to treat amino acid production wastewater. UASB′s COD removal rate can reach 60.8%; as anaerobic effluent is treated by SBBR, effluent COD can be reduced to 150mg/L, the average COD removal rate is 96.1% and effluent ammonia is less than 25mg/L.