Journal of Wuhan University of Technology

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Synthesis and Hydrogen Storage Properties of Metal Doped Mesoporous MCM-48

ZHANG Guangxu, FANG Yuan, CHEN Bo, GAO Weifang, ZHAO Xiaoshuang

. 2011, (11): 1-105.

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With cetyltrimethylammonium bromide as mouldboarding agent, tetraethyl orthosilicate as silica source, by adding metal salts solution directly into the process of synthesis which is the first step, we can get metal doped mesoporous molecular sieve MCM48 through hydrothermal synthesis in alkaline conditions. XRD, N2 adsorptiondesorption can characterize the structure of some product, and the results show that the metal doped mesoporous molecular sieve maintained the threedimensional cubic mesoporous structure, but the consistency was slightly lower and the specific surface decreased. Research on the hydrogen storage capability of this mesoporous molecular sieve suggests that the amount of hydrogen adsorption of pure MCM48 increases with temperature decreasing. At 0.2 MPa, -25 ℃, the amount of hydrogen adsorption can reach 0.678 8%; In metaldoped mesoporous molecular sieve, Ni, Fe, Pd can help improve the hydrogen storage capacity, Zr, Mg negatively will reduce the amount of hydrogen adsorption, of which NiMCM48 gets the highest amout of hydrogen adsorption at 0.2 MPa, -10 ℃, reaching 0.772 0%.

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Investigation on the Hydrothermal Synthesis of (K_1-xNa_x)(Ta_1-yNb_y)O₃Nanopowders

GU Qibin¹, WANG Zhao², LIU Shali²

. 2011, (11): 6-9.

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(K_1-xNa_x)(Ta_1-yNb_y)O₃(KNTN) nanopowders with different compositions were synthesized by hydrothermal method. The results showed that KNTN nanopowders with atomic molar ratio of K/Na = 1 could be obtained at high medium alkalinity condition. The phase structure gradually changed from monoclinic to the tetragonal phase as the increasing of K element of KNTN. The molar ratio of Ta/Nb in KNTN shows a linear relationship with that of the Ta2O5/Nb2O5 in the starting materials. With the increase of Ta content in KNTN, the phase structure changed from orthorhombic to tetragonal phase and finally stabilized at a cubic phase of perovskite structure, at the same time the morphology of the nanoparticles changed slowly from rectangular to cubic shape.

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Study on Image Detection Method of the First Bubble on Magnesium Melt under Complex Background

XU Sixiang， GAO Peiqing, MA Aiping

. 2011, (11): 10-13.

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The precision of hydrogen content detection instrument in magnesium melt based on the first bubble method intensively relies on precise recognition of the first bubble precipitated on the surface in magnesium melt. This paper had recognized the bubble automatically by image processing technology. The character of the image represents lower SNR (signaltonoise ratio) and contrast when the background varied gradually because of the influence of vibration and gradient temperature, and the pixels of the target are low. The detection algorithm of the first bubble was presented that depended on wavelet transform and adaptive graylevel threshold splitrun combining with the open algorithm of mathematical morphology, at last the bubble was detected. Based on this algorithm, the verification was constructed for the image sequences of the fore and after of the first bubble precipitated. The result of experiment showed that satisfactory results could be achieved through the detection method mentioned above, the detection probability of the target is 97.3%.

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Analysis of Structure and Properties of Korla's Andalusite in Xinjiang

WU Jianfeng， LENG Guanghui， HUA Quan，NI Yang，XU Xiaohong，ZHAO Zhao

. 2011, (11): 14-19.

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The physical and chemical properties and high temperature performance of Korla andalusite were systematically studied in this article. The chemical composition, phase composition, microstructure, and physical and chemical changes in firing process of raw materials were analyzed by testing technology such as XRF, XRD, SEM, TGDTA and so on. The samples made by semidry pressing method with adding a little hightemperature flux. High temperature performances of samples were studied. The research shows that the content of Al₂O₃ is about 50.87%, SiO₂ is about 43.25%, and the main phase are andalusite and quartz in raw materials. Range of the fire temperature of samples is wide (1 300~1 540 ℃), and bending strength is about 75 MPa, high temperature volume stability is good (firing shrinkage is about 1%), water absorption is between 7.80% and 17.25%, porosity is between 17.89% and 33.42%. Thermal conductivity is 1.21 W/（m·K）, heat capacity is 0.65 J/(g·K) ,thermal diffusivity. of samples at 600 ℃ is 0.84×10^-2 cm²/s. The results indicated that Korla andalusite is a good ceramic raw materials, it is fit for making the ceramic which have good high temperature performance and thermal shock resistance.

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Effect of HCPEB on Frictional Wear Resistance of 3Cr2W8V Mold Steel

CHEN Yuanfang, XU Hongbin, HU Jianjun YANG Changhui，HAN Chao

. 2011, (11): 19-23.

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〗The sample of 3Cr2W8V mold steel on heat treatment, HCPEB treatment and HCPEB surface alloying Al were made and the frictional wear resistance was investigated by micro hardness tester, roughness tester and friction testing method. The results indicate that the initial surface roughness has important influence on after HCPEB treatment surface roughness; Moreover, it is found that this seems to be all sample after electron beam treatment exhibited higher section hardness compared to original sample, electron beam surface alloying Al sample section hardness is increased by 10%, directly electron beam treatment sample section hardness is increased by 24%～33%；Furthermore, the friction coefficient appeared suddenly enlarge phenomenon, the value of enlarge friction coefficient is the same as the original sample’s. The weight loss of HCPEB treatment and HCPEB surface alloying Al of 3Cr2W8V decreased 22.7%、 72.7% compared to original sample.

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Curing Characteristics of Epoxy Asphalt Studied by Differential Scanning Calorimetry

QIAN Yuchun，CHEN Shuanfa，CONG Peiliang

. 2011, (11): 24-27.

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The curing characteristics of epoxy asphalt and the relevant epoxy resin were studied by nonisothermal differential scanning calorimetry (DSC) technique. According to the DSC graphs at different heating rates, the curing characteristics of epoxy asphalt were studied which lay a foundation for the optimization of the curing and construction technology of epoxy asphalt. The results showed that, after the curing of the epoxy resin, the gelation temperature, curing temperature and the posttreating temperature of the asphalt were all increased. So, the thermal stability, especially the high temperature resistance of the epoxy asphalt was improved rapidly. Further study found that the effect of diffusion should be considered during the curing study of the epoxy asphalt and the curing characteristic of epoxy asphalt with part of the diffusioncontrolled was put forward.

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Effect of Temperature on Aggregate States of Hydration Products C-S-H Gel of Cement with High Content of Fly Ash

YU Wenjin, LUO Yongchuan, GONG Zicheng, DING Qingjun

. 2011, (11): 28-32.

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Effect of curing temperature and temperature variation on siliconoxy tetrahedron aggregate states of hydration products CSH gel of cement with high content of fly ash materials by highresolution solid 29Si NMR、XRD and FTIR testing techniques. The results show that siliconoxy tetrahedron aggregate states CSH gel and contents of aluminumoxy tetrahedron increased and then stabilized with the increase of curing temperature. Curing at normal temperature was good for increasing siliconoxy tetrahedron aggregate states of CSH gels and contents of aluminumoxy tetrahedron at the periods from 7 d to 28 d.

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Synthesis on Oxidizedacidifiedetherified Starch as Superplasticizer

ZHAO Ping,YAN Yun, HU Zhihua, WANG Tiantang

. 2011, (11): 33-38.

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The oxidizedacidifiedetherified starch was prepared by corn starch by via sequebtial process of sodium hypochlorite oxidation ,acidolysis treatment and oxirane etherification., and the influence of process parameter to waterreducing characteristic on the cement paste were investigated.The optimum control value of the critic parametertime ,temperature,pH and raw material amount of every stage were got. The optimal amount of oxidizedacidifiedetherified starch is 0.3%,the main active mechanism of which is steric hindrance.

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A Quick Rehabilitation Technique for the Accidental Damage of the Epoxy Asphalt Concrete Pavement

QIAN Zhendong, CHEN Leilei, WANG Hui

. 2011, (11): 39-43.

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In order to quickly rehabilitate the accidental damage of the asphalt concrete wearing course of steel bridge deck, to prevent it become the start point of the pavement damage, a quick rehabilitation material was presented and evaluated. The repair material and technique of the accidental damage on the steel deck pavement was firstly introduced. Secondly, the accident damages were simulated and repaired in the laboratory. After that, a three point bending beam test and the wheel tracking test were employed to assess the strength and the deformation resistance of the repaired specimens. The test results showed that the strength of the repaired beams is not less than that of the original beams, and the deformation of the 8 hcured specimen after the wheel load for 1 h was only 0.813 mm, and the dynamic stability of the specimen was 8 300 cycle/mm, indicating a good deformation resistance. At last, the rehabilitation technique was successfully applied to the accidental damage on the wearing course of a long span steel bridge deck.

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Coarse Aggregate Gradation Design of Asphalt Mixture by Gradually Filling Test

ZHANG Yemao,CHEN Shuanfa,HU Guangwei

. 2011, (11): 44-48.

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The gradation of asphalt mixture is the main factor on the asphalt pavement performance, and coarse aggregate skeleton is the primany factor that effects the distribution. The article analyses the interaction among the particle sizes of coarse aggregat through the aggregate gradually filling test and VCA and CBR double controlling index, and identifies the key sizes of coarse aggregate by uniform design and grey system theory, and recommend each particle size range content of coarse aggregate. The results show that coarse aggregate skeleton gradation of asphalt mixture by filling test have good correlation with VCA and CBR.

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Anylisis of Effects of Gradation and Compaction Number on Mixture Performance

HE Changxuan

. 2011, (11): 49-54.

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This study investigates the effects of different aggregate gradations and compaction number on road performance of asphalt mixtures. The dynamic stability, low temperature bending failures strain, soaking marshall stability,AASHTO T283, split strengthen and freezethaw split strengthen are used to evaluate the road performance. Three gradations (Sup13, Sup20 coarse and Sup20 fine) and two compaction (100,125) number were selected. Means comparison using Tukey test is used to analyze. Increasing compaction number would bring on higher dynamic stability, low temperature bending failures strain, split strengthen and freezethaw split strengthen.Compared with fine gradation, coarse gradation gives higher dynamic stability, low temperature bending failures strain, split strengthens and freezethaw split strengthen under the same compaction number. There are no significant differences between water stability with coarse and fine gradation or different compaction number. Coarse gradation is toppriority compared with increasing compaction number.

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Prediction Model of Air Void Content for Porous Asphalt Concrete

JIANG Wei，SHA Aimin，XIAO Jingjing，LI Rong

. 2011, (11): 55-59.

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The influence of the key sieve passing rate and key aggregate content to air void content was analyzed based on the laboratory test results of porous asphalt concrete. According to the results, 4.75 mm, 2.36 mm, 0.075 mm sieve passing rate and 1.18~2.36 mm aggregate content were selected as model parameters to establishing a prediction model of PAC13 with multiple linear regression method. The results of the study show that sieve passing rate of 2.36 mm & 4.75 mm and aggregate content of 1.18~2.36 mm have linear negative correlation with air void content; Prediction model of air void content with the four parameters has good fitting results; Air void content would influenced by Asphalt content or bitumenaggregate ratio, air void content will decrease by 1.1% while the bitumenaggregate ratio increased by 0.5% in general.

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Berth and Quay Crane Collaborative Optimization Research at Continuous Terminals

ZHAO Kunqiang,HAN Xiaolong,LIANG Chengji

. 2011, (11): 60-65.

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Container port is extremely important as the hub of container transport ,it’s operational efficiency related to port business operating costs and customer satisfaction.As the berth and crane resources are scarce resource, its scheduling optimization is directly related to the efficiency of port operations. In this paper a mixed integer programming model is built. First we assign berth and crane to the ships, and then set up a quay crane scheduling model to assign specific quay to the ship. The result shows that using the two model can get satisfied solution.

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Integrated Berth Allocation and Quay Crane Scheduling by Memetic Algorithms

LE Meilong, LIU Fei

. 2011, (11): 66-71.

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To improve operation efficiency of container terminals, optimization of berth allocation and quay crane scheduling is discussed in this paper and berth allocation problem is abstracted as package problem, then a mixedinteger programming model is presented. The proposed Memetic algorithm is applied to solve it. Experiments results show that Memetic algorithm is superior in running time.

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Study on Feature Extraction of Concrete Structure Cracks

WEI Jun, CAO Longfei, ZENG Yanxia,DONG Rongzhen, CHEN Shaolei

. 2011, (11): 76-81.

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Based on images of concrete surface cracks which was a longdistance shot, some special image processing algorithm, such as image graying, image enhancement, image segmentation, dilation, erosion and boundary tracking, were used to obtain the cracks length and width, and one software was developed. The results show that this method of cracks length and width measurement has some features of feasibility and accuracy, and the development presented may provide a new technique for the determination and analysis of structural cracks.

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Finite Element Analysis on CA Mortar of CRTS Ⅱ Ballastless Track Slab

ZHU Xiaobin, YAO Ting, LIU Jiaping,HONG Jinxian, ZHAO Guotang, WANG Tao

. 2011, (11): 76-81.

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Engineering practice indicates that CA mortar of CRTS Ⅱ ballastless track slab has high cracking risk in the early stages after construction. To find the rules of cracking of CA mortar, finite element analysis is used to compute the early stage cracking risk factor of CA mortar of CRTS Ⅱ ballastless track slab. The results show that the CA mortar of the two sides of CRTS Ⅱ ballastless track slab tend to crack more easily than the inside part. The early shrinkage stress of side part CA mortar increases with the development of age and its cracking risk factor exceeds the critical point for the first time. Calcium oxide type expanding agent can effectively delay the cracking time of CA mortar. The cracking risk factor is below the critical point during the whole observation period when the drying shrinkage of CA mortar is less than 120×10-6. The research results provide references for the prevention and control of crack in CA mortar in China.

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Numerical Analysis on the Aseismic Performance of Prestressed Concrete Voided Slab Simple Beam Bridge

XUE Anshun, GUO Hongbing

. 2011, (11): 82-87.

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Aiming at the aseismic problem of urban bridge structures in the earthquake area, based on Finite Element Method (FEM), the largescale nonlinear finite element program MIDAS/Civil and the 3D FEM are used to establish the dynamic finite element model for urban prestressed concrete voided slab simple beam bridge in the earthquake area. Under the earthquake action of E1 and E2, the aseismic performance such as antibending, antishear capacity of key sections, and thickness and antisliding stability of the bearing have been analysed. According to the theoretical calculation analysis results, practical aseismic measures have been proposed, and the necessary theoretical guidance and technical support will be provided for construction quality control of urban bridge structures in the earthquake area.

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Research of a 3D Flow Mathematical Model with 〖JZ〗Hydropower Plant Closure

XIAO Taoli,LI Xinping,WEI Wenjun

. 2011, (11): 88-92.

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The 3D flow mathematical model is set up by using σ coordinate transformation technique. The model is confirmated by the use of water level and flow velocity in survey region,the results indicate that it has a good mass conservation properties.The model is employed to carry out a numercial simulation of the water level changes between upstream and downstream, the velocity distribution of axis section and its nearby when the closure gap width changes from 50 m to 35 m,the results show that the calculation results of 3D flow mathematical model than the physical model obserbation of around 10% are too big,the causes were analyzed in this paper, and the conclusion is that the 3D model is suitable for the river clouser construction of the pubugou hydropower station when the calculation multiplied by 0.95.The results provide a new research method for the hydropower plant closure.

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Design & Realization of the System of Threedimensional Conflict Analysis for Integrated Pipe Network of Metro Station

WANG Shuqiang, WANG Qiankun, ZHANG Yong

. 2011, (11): 93-96.

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Guided by the ideology of collaborative aided design, by means of computer and visualization technology to build a metro station integrated pipe network threedimensional conflict analysis system. This system has realized the function of automatic modeling from 2D to 3D, which including integrated pipe network, architecture, mechanical and electrical equipment and cable tray. This system has also realized property management of 3D models and conflict analysis among models. Application of the system has effectively reduced the difference, leak, fault, collision and other issues among professional, improved design quality and shorten the design cycle and, indirectly, saved installation costs.

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Performance Study on the Decontamination of NO_xfrom Vehicle Based on NanoTiO₂ Penetrated on the Surface of Asphalt Road

CHEN Meng, CHU Jiangwei, LIU Yanhua

. 2011, (11): 97-101.

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In order to purify NOxof vehicle emissions, we had utilized permeability technology to make asphalt road have purification NOx function that based on nanometer titanium dioxide of photocatalysis characteristic and asphalt road material porous characteristic.At the same time,some simulation experiments and mechanism analysises had in order to ensure practical applying effect in the real environment outside.It included surface friction, humidity and light. The experiments showed that the environmental protection materials of asphalt nanoTiO2made by permeability technology had good decontamination effect in 2 mm wear and tear of scope. Simultaneously, adequacy humidity environment, shorter and stronger of light was advantageous in the NOx purification effect.

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Experimental Study on Adsorption Performance of Malachite Green by Spent Cottonseed Hull Residue

YUAN Xiao，GONG Wenqi, XIE Chuanxin, ZHOU Qi

. 2011, (11): 102-106.

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Spent cottonseed hull residue(SCHR)，which has been used as pleurotus ostreatus cultivation, was used for the adsorption of malachite green. The effects of some factors, such as SCHR dosage, reaction time, salinity, initial concentration of malachite green and temperature, on the removal of malachite green were investigated. The results showed that: with the augment of SCHR dosage and reaction time, the adsorption removal rate increased, and the rate declined with the increased initial concentration of malachite green and salinity. The isothermal test data of biosorption fit the Langmuir model and the Freundich model well, and the malachite green adsorption onto the biosorbent was spontaneous and endothermic. Higher temperature benefited the adsorption, and the maximum capacity of adsorption was calculated as high as 122.87 mg/g.

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Experimental Study on Purification of a Lowcarbon Graphite Ore by Flotation

ZHANG Lingyan，HUANG Wen，QIU Yangshuai，PAN Li, TU Wenmao

. 2011, (11): 107-111.

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China is a big country of natural graphite resources. The reserves, production and export volume of graphite is first in the world, but with the development of production , the grade of the rest graphite is very low, and the optional drop result in the recovery rates decline. Through the experiment , we need to recovery the low grade graphite by flotation ,make sure the grade of concentrate up to the national highcarbon standards, make full use of graphite resources to expand the scope of application of graphite.Based on the Heilongjiang Hegang thin flake graphite whose grade is 12.74%, the emphasis of the study was placed on the floatation flow, such as once rough grinding, once sweep election, then five times regrinds six selections to the crude concentrate, one more election to the merges of the middling(1~3),and the the middling (4, 5, 6, 7) returns to the regrind I. Taking the coal as cellector, the 2# oil as foaming agent and the lime as regulator, the result with improvement in the grade of concentrate to 93.6% through the routine floatation method was achieved. The flotation recovery rate reaches to 91.42%.

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Rapid Determination of Chlorophylla in Lake Water by Direct Fluorophotometry

XIANG Qingqing, TANG Heqing, ZHU Lihua, YUAN Songdong, ZHANG Aiqing

. 2011, (11): 112-115.

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According to the intrinsic fluorescence of chlorophylla, a fluorophotometric determination of chlorophylla in lake water was developed for the online monitoring of the growth of algea. The fluorophotometric measurement was carried out with excitation at 418 nm and emission at 680 nm. The fluorescnece intensity responded with the concentration of chlorophylla linearly in the range of 0.28 ~88 μg/L with a correlative coefficient of 0.999. By using green algae as an example, the relationship between concentration of chlorophylla and fluorescence intensity of green algae in water was established. Thus, the algea biovolume can be determinated rapidly by fluorophotometric to provide the scientific basis for the early warning of water bloom. Comparison was made between this method and the traditional extraction way, and no significant difference was found. The proposed method was successfully applied to the determination of real water.

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Research and Application on Stormwater Biofiltration Treatment Technology in Australia

ZHANG Xiangling, ANA Deletic

. 2011, (11): 116-119.

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A new kind of stormwater biofiltration treatment technology in Australia was introduced. The major research and progress on the stormwater biofiltration system’s configuration, filler media selection, plant selection and other aspects of the purifying effect which were researched by Facility for Advancing Water BioFiltration (abbr FAWB) were summarized. Aimed at the stormwater biofiltration system’s advantages in suspended solids, heavy metals and nutrient pollutants removal, and system configuration’s characteristics for effectively store reuserainwater, the technical improvements were suggested for the stormwater biofiltration treatment system’s research and reference design in China.

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Optimization Analysis of Threelayer Blown Film Dies Based on Orthogonal Experiment

LIU Mingyao,DANG Wanjun,XIE Guoxiang,TAN Yuegang

. 2011, (11): 120-125.

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In order to obtain the film with uniform layer thickness,no weld lines and no crystal points,aiming at producing composite film of LLDPE/LDPE by the structure of threelayer spiral mandrel dies, the effects of structural parameters on the flow uniformity of the outlet, the stagnation zone of the melts and the maximum pressure in the die have been analyzed by applying FLUENT simulation. And better parameters are selected using orthogonal design.The results indicate:the compression ratio of compression width matters the most to flow uniformity,outer initial clearance matters the most to stagnation zones,middle intial clearance and spiral decreasing angle matters the most to the maximum pressure drop in the die. This will provide a new method for the structure optimization of threelayer spiral mandrel dies.

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Experimental Investigations on Threedimensional Flow Field Around the Tail of Gasliquid Slug Flow in Microchannels

WANG Ling, LUO Rui, WANG Buxuan

. 2011, (11): 126-130.

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A Threedimensional MicroPIV experimental and measuring system was used for studying threedimensional flow field properties of slug flow in microchannels. Through processing images, threedimensional velocity flow field of the liquid around the tail of slug bubble was obtained. There was a liquid flow circulation but with an opposite turning direction near the tail of the bubble. In the flow field far away from bubble, a more uniform distribution of liquid velocity in the microchannel cross section was established in comparison with a singlephase pressure driven flow. The fluid near the bubble tail had a larger velocity to the stagnant point along the bubble surface. The fluid between the bubble surface and the microchannel walls had a complex motion that they might be pushed to the bubble tip if closer to the bubble surface or might be passed if closer to the walls.

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Analyze the Structural Strength of Cutter Suction Dredger Based on ANSYS

YANG Zhenyi, ZHU Hanhua, FAN Shidong, ZHU Junchao

. 2011, (11): 131-134.

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Cutter suction dredger is commonly used dredging equipment, underwater mining cutter is its core component. In this paper，twodimensional watersaturated sand flat cutter cutting process theory is applied to the force analysis; From threedimensional shape cutter start the ball cone cutter, for example, create the cutter model, finite element software pair tool to calculate the stress strain analysis, design and manufacture of cutter and strength check of reference.

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Simulation of Nonlinear Torsional Vibration of Universal Joint Based on MATLAB

XU Xiang，ZHOU Ruiping，WANG Mengsheng，QI Liang

. 2011, (11): 135-138.

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The nonlinear torsional vibration equations of universal joint is derived by the first kind of Lagrange’s equations, and the simulation model of this system is obtained, which was proved to be correct through calculation and simulation results in a special case, then the relationship that the natural frequency decreased with the angle increasing is gotten through the modification parameter, and the conclusion that the angle can be omitted in torsional vibration calculation when it is less than 20 ° is drawn, which provide theoretical support for universal joint design and application in ship propulsion shaft.

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Research on Crossplatform Video Codec Based on FFMPEG

HU Cong, ZHOU Tian, TANG Ludan

. 2011, (11): 139-142.

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A software implementation of video codec for video monitoring is presented. Monitor client used S3C2440 as embedded hardware platform, acquired video with OV9650 of CMOS camera, transmitted to the monitoring server with FFMPEG coding. Monitor server received video stream, decoded and playing realtime by FFMPEG, realized remote monitoring. The experimental results show that the system achieves the monitor client video acquisition, encoding, and monitor server decoding and playing.

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Adaptive Synchronization of a New Complex Chaotic System

ZHANG Xuebing,YAO Hongxing

. 2011, (11): 143-146.

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In this paper a new complex chaotic system is presented .Some of its basic dynamical properties are sdudied. The synchronization is achieved with fully unknown parameters through designing controller and parameters updating rule. It is proved that the validity of this synchronous method theoretically is feasible by Lyapunov method. Finally, a simulation is conducted with Matlab to prove the synchronization of the complex chaotic system. Simulation results show that this method is feasible and efficient.

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An Adaptive Filter Algorithm of Exponentiallyweighted Multiple Attenuated Memory

TIAN Chong，WANG Xingliang，LU Yane

. 2011, (11): 147-152.

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This thesis firstly research the phenomenon of valuation instability in which Kalman filtering process in GPS positioning. The method of orthogonal matrix decomposition is used to solve the failure of noise covariance matrix variance in meeting diagonal matrix, which is led by the correlation between various measurement noises. Then by the UD matrix decomposition of the one step forecast mean square error in which adaptive algorithm of multiple exponential weighting fading factors matrix, the decomposition matrix is applied in updating processing of the Kalman filtering, as well, the solving process of multiple fading factors matrix is provided. The simulation result demonstrates that the algorithm enhances valuation stability, improves positioning accuracy and has the function of preventing filter divergence thus verifies the effectiveness of this algorithm.

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Study of Edge Fitting Model of Point Spread Function Based on Gauss

TIAN Yuanyuan, TAN Qingchang

. 2011, (11): 153-156.

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The paper adapts edge model of convolution between point spread function based on Gauss fitting and ideal edge. The gray distribution of edge pixel is fitted based on the model. Compared point spread function of Gauss with Bessel, the research shows that the effects using Gauss is better than the latter and the value of parameters obtained by Gauss is closer to the given value than the latter.

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