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In order to study the effect of adding substrates on soil seed banks (SSBs) germination characteristics, vermiculite (inorganic substrates), rice husk char (organic substrates) and their mixed substrates were selected to be added to SSBs by different ratios. After the germination test, the results show that SSBs in different treatments present different germination characteristics. In this test, the nutrition of organic substrates is more important for promoting the rate of seeding emergence, while the inorganic substrates is better for greater density and seeding community diversity. T1(rice husk char: soil=1:9), T5(rice husk char: vermiculite: soil=2:1:7) and T4(vermiculite: soil=3:7) correspond the best promoting effect on these three aspects. Thus the substrates selection should be determined according to specific objectives during vegetation restoration. Mixed substrates combine the advantages of organic and inorganic substrates, which leads to comparative advantages in all aspects.

The theoretical calculation of PHC pipe pile negative friction resistance is difficult to obtain valuable results due to many complex factors involved, such as soil properties, consolidation conditions and actual working environment, so the field monitoring is the only feasible method. The pile negative friction resistance can be got by pre-buried sensors inside the pile to monitor the changes of stress and strain of shaft. However, for PHC pipe pile, the sensors can not be embedded and protected effectively in the process of pile manufacturing, which makes the negative friction resistance of PHC pipe pile become a very thorny problem. Based on the improved field monitoring method and data analysis of sliding micrometer technology, a new method was introduced into the PHC pipe pile negative skin friction resistance testing in this paper. We can got not only the PHC pipe pile negative friction resistance, distribution range and neutral point position with different load or time, but also the strain distribution, axial force distribution, skin friction resistance and toe resistance distribution of pile, etc. The practical engineering application shows that the new method is very effective to monitor PHC pipe pile negative friction resistance and very beneficial to further research on formation mechanism and theoretical calculation of negative friction resistance of PHC pipe pile.

The concrete used in transmission lines are basically for foundations. The foundation concrete of transmission lines in corrosive environments has shown serious deterioration, which usually caused by concrete deterioration, rebar corrosion, degradation of bond strength between rebar and concrete due to various corrosive effects. Field tests are carried out in Wuhu area to research the durability of foundation concrete of transmission lines. And test results show that the concrete strength in the air is a litter higher than underground and the carbonization depth at the windward side is the largest of each foundation and the leeward side is the smallest, while those underground are close to zero.

According to the rock high-cut slope excavation engineering practice of a substation in Jiangxi, with the goals of stable and economic rational slope design, numerical simulation research of the slope ratio and unloading platform and design optimization work was carried out. The slope safety factor, displacement and plastic zone distribution changes of different slope ratio and platform setting programs were obtained. The results show that:(1) the adjustment of the slope ratio and platform can significantly affect the slope displacement and plastic zone distribution, reasonable slope ratio and platform can reduce the horizontal displacement and plastic zone of slope, increase the safety factor and stability;(2) the slope monitoring results show that numerical simulation optimization design is feasible, and the excavation slope maintain security and stability during the construction period, and economic benefit has been obtained. The research conclusions can provide technical support for the engineering design, and reference for design and research of high-cut slope excavation engineering with similar conditions in that region.

A process that combines a vacuum expandable pattern casting V-EPC with self-propagation high-temperature synthesis SHS of TiB2/TiC particles for the fabrication of the TiB2+TiC duplex particulates reinforced carbon steel matrix surface composite are introduced in this paper. The effect of ferrotitanium addition in the SHS reactants on the macro and micro structures as well as hardness is investigated. It has been found that with the increase of ferrotitanium addition, the concentration of synthesized particles in the layer gradually increases to maximum, then decreases. The hardness gradually decreases from the surface compound layer to core and the maximum hardness of 1682HV is obtained on the composite surface.

The fatigue analysis of the mental bellows had been analyzed. The fatigue tests were designed based on orientation displacement Compared the result of analysis on ANSYS with the result of experiment, the method of fatigue analysis is reliable. Furthermore, an important suggestion should be made that the orientation displacement should be reduced when the mental bellows was usedKeyword: fatigue analysis; mental bellows; ANSYS

This paper analyzes the defects of a scraper stem humidifying machine, reforms the equipment structural and solves the problem of leaking steam and water, which effectively improved the reliability and increased the temperature and humidity of tobacco stem at the discharge end. It has a good reference value for analyzing and improving tobacco humidifying equipments.

The full-wave band CCD system is widely used for military,civil or photography of criminal image and extraction analysis,its wavelength is range between 200 nm and 1200 nm,including ultraviolet,visible light and infrared.Through translating blanck visibleimage into optical image,and realizing collecting of weak signal under low illumination case and collecting and processing of high quality image,it makes Full-wavelength CCD system the powerful features such as the topography and landform scaning,traces exploration,file inspection,holographic photography and image processing.The whole band CCD system structure,characteristic and the application of the image interpretation technology were briefly introduced in this paper,and experiment band CCD selected was validated.

Fine particulate matter PM2.5 is the main factor of "Haze” weather. The paper chose the content of various indicators in the sets of air quality index AQI detected by a monitoring station in Wuhan city as samples. Based on the methods of Spearman's rank correlation coefficient and Kendall rank correlation coefficient to establish mathematical model, the paper analyzed the correlation between the content of PM2.5 and other five basic detection indicators and corresponding pollutants, with providing theoretical and experimental evidence for air management work. Two methods of the experiment results showed that PM2.5 (content) has a strong correlation with sulfur dioxide, nitrogen dioxide, particulate matter, carbon monoxide (content), and had a negative correlation with ozone (content).

In this paper, BP neural network model is used to establish the occurrence and evolution model of PM2.5 in an area in Xi'an city. In the model, wind, humidity, season, SO2,NO2,PM10, CO,O3 (in one hour ) and O3 (in eight hours ) and other influence factors are all considered. The model has good reliability, it can accurately forecast the value of PM2.5 and its variation in the near future, which can provide the basis for the PM2.5 control.

Fuzzy c-means (FCM) algorithm is an unsupervised clustering algorithm for image segmentation, and has been widely applied because the segmentation results are consistent with human visual characteristics. Enhanced fuzzy c-means clustering (EnFCM) algorithm is the improved FCM algorithm, which reduces the computational complexity. But, both FCM algorithm and EnFCM algorithm, clustering number still need to be manually determined. This paper, in order to realize the automation degree of algorithm, presents an improved algorithm. It first analyzes the histogram, then automatically determines the clustering number and peak value of each class through use of the peak point detection technology, finally segments image by using EnFCM algorithm. Experiments show that this method is a kind of faster fuzzy clustering algorithm with automatic classification ability for image segmentation.

For mutual occlusion problem in multi-object tracking process, a novel tracking algorithm based on bilateral structure tensor corner detection is proposed, which can separate the objects correctly when they experience mutual occlusion. Firstly, it gains the information of each object corners. Secondly, when occlusion occurs, it makes use of K nearest neighbor algorithm combining with the nearest algorithm to classify the corners in occlusion region. Finally, the multi-object tracking algorithm is proposed. The experimental results show that the proposed method can separate the objects correctly and track the objects effectively, when they experience mutual occlusion, even the object changes its motion direction after occlusion.

In order to increase the output power of the photovoltaic system, the maximum power point tracking is needed. As the starting point of research in the output nonlinear characteristics, analysis of the advantages and disadvantages of the conventional algorithm and have the poor dynamic and steady-state performance of the maximum power point tracking(MPPT), the improvement method of golden section(IGSS) is applied to the photovoltaic power generation system. The results indicate that the method can quickly track the maximum power point of photovoltaic cells.

Buckling restrained braces (brb), as a new kind of component for shock absorption, improved the ordinary support shortcoming of easy bearing flexure,when the earthquake take place, it has very good consumeing energy ability and ductility. In recent years, it has been used widely in the USA、Japan and Taiwan ,This article introduces classification of brb briefly as well as the influence of mechanics property and arranging position and so on to resist earthquake.

The principle and mechanism of triphenylarsine (TPA) accumulation of arsenic hyper-accumulator-Pteris vittata L was investigated to remediate soil contaminated by abandoned arsenical chemical weapons in somewhere in Jilin Province, by means of soil and water culture in the greenhouse. Through analysis of changes in concentrations of total arsenic and TPA in Pteris vittata L. and in inorganic arsenic concentration of water culture solution, observation of apparent characteristics and determination of organic arsenic forms in Pteris vittata L., results show that Pteris vittata L. could accumulate TPA in soil when the concentration of TPA in soil is less than 150 mg/kg, and the concentration of arsenic in Pteris vittata L. increase initially and then decrease with TPA concentration increasing. When Pteris vittata L. had grown 3 months, the TPA concentration reaches its maximum, i.e. 316.85mg/kg (dry), while, the bioconcentration factor (BCF) decreases gradually. Although Pteris vittata L. still could accumulate TPA after TPA concentration reached more than 150 mg/kg, arsenic concentration in Pteris vittata L. significantly reduce due to stress effect of TPA.

A data collection repeater based on ARM Cortex-M3 core for environmental monitoring is introduced in this paper. The chip STM32 is used as CPU processor, CC2530 module as a sink node of Wireless Sensor Networks, the collected data is sent to monitoring center by GPRS network. Integration of WSN, ARM and GPRS, the collection of environmental parameters and capability of wireless transmission are achieved in low-power conditions. Hardware structure and application program of the repeater are given.

The dynamic recrystallization of commercially pure titanium was investigated by compression tests on Gleeble-1500D thermal simulation test machine at temperature of 700950 °C and strain rate of 0. 015 s1. The total compression deformation is 0.7(true strain). The kinetics of dynamic recrystallization of commercially pure titanium at 950 °C was modeled by Avrami equation. The results show that the dynamic recovery and recrystallization obviously occur during compression. The flow stress increases to a peak value and gradually decreases to a steady state. The flow stress is decreased with the increase of deformation temperature and it is increased with the increase of strain rate. The Avrami kinetics model of dynamic recrystallization of commercially pure titanium at 950 °C is obtained .

To study the effect of different dosage of recycled asphalt mixture particles on the performance of concrete, the mechanical characteristics, shrinkage performance and durability testing were performed, the results show that the compressive strength and flexural strength of concrete are decreased with the increase of dosage recycled asphalt mixture particles, while still meet the regulatory requirements; the capability of plastic shrinkage resistance can be improved by incorporated recycled asphalt mixture fine particles, yet slight effective on the temperature shrinkage; the durability of concrete changes as a result of incorporation of recycled asphalt mixture fine particles, the durability of concrete with a dosage of 20% is considered in the optimal state, so the recommended dosage is 20%.

Cross-prestressed concrete pavement, without setting expansion joints, can extend its service life, improve its bearing capacity and make the continuous construction possible. In recent years, it has been successfully applied to toll plazas, short subgrade of the highway and the overweight or overloaded road. Materials choosing, construction method of the cross-prestressed concrete pavement was presented in details and some relevant problems during the construction have been discussed in this paper.

To well know the properties of ionic liquid mixtures, the viscosity of the binary mixtures containing the methylbenzene and imidazole ionic liquids (1-butyl-3-methylimidazolium tetrafluoroborate [Bmim][BF4] or 1-butyl-3-methylimidazolium hexafluorophosphate [Bmim][PF6]) were measured. Within the temperature range from 298.15 K to 308.15 K, the viscosity of the four binary systems decreased sharply as the increase of temperature. The viscosity decreased slowly in the temperature range from 308.15 K to 338.15 K. The viscosity also decreased with decreasing of the mole fraction of ionic liquid. The viscosity of methylbenzene in the imidazole ionic liquids was in sequence: [Bmim][BF4] < [Bmim][PF6]. The experimental viscosity values had been correlated using the binary parameters of Vogel-Fulcher-Tamman equation.

It is very crucial to analyze the flexural bearing capacity of the steel-high strength concrete composite beams, but the combination on the flange of steel beam and their bearing capacity is limited with certain inevitability,in addition, in the negative bending regions of continuous composite beams, with the constant increase of load, the process of the whole structure will cause damages in the negative moment region. In order to avoid this kind of damages, we must use general finite element program ANSYS to analyze thebearing capacity of the steel and high strength concrete composite beams. Besides further studying the influence factors of bearing capacity, and ensuring the safety of our engineering performance can be in favor of the engineering structure.

In the process of detecting and calibrating for power equipments, it appears a phenomenon that standard equipment is damaged by harmful random large current from tested equipment. This danger signal mainly occurs in the transient state of tested equipment, i.e., in a short time after starting to output new set current. This paper proposes a method for protecting standard equipment to eliminate damage caused by random large current. Its content mainly describes one of the key parts of this scheme including accurately sampling and transient signal removing intelligently in details. Design the related current sampling circuit, test results show that the resolution of circuit can reach to 10mA, which satisfies the work well.

To overcome the defect of the traditional method to determine attribute weight in the multiple attribute decision making problems, this paper proposed a kind of data fusion method based on The D-S Evidence Theory improved by The Grey Correlation Analysis. The method, firstly, calculated the basic probability assignment functions discount factor based on The Grey Correlation Analysis, then let the subjective weight and objective weight together based on D-S combination rules in order to avoid the deficiency of the single weighting method. Using the fusion of evaluation indexs subjective and objective weight of mobile phone product solution as an example, the results show that the proposed method is effective.

There are a lot of data in the real life showed by the form of multimedia data. But the vast majority of data mining tools are developed for the relational database. Therefore it is necessary to introduce the service in multimedia data mining and multimedia data mining technology to improve service quality and level of knowledge. Multimedia data mining and knowledge services are introduced and multimedia data mining process is given. Meanwhile, multimedia data mining system prototype framework is proposed. In the end multimedia data mining application in the knowledge services is discussed.

A series of water-swelling rubbers (WSR) were prepared by directly mixing room temperature vulcanization-2 components silicone rubber (RTV-2 SR) with superabsorbent polymer (SAP) and nanofiller (s) (halloysite nanotube or/and CaCO3). The effects of component on its mechanical behaviours and water-absorbent properties such as degree of swelling, swelling ratio, and weight loss ratio were investigated. The equilibrium swelling ratio increased with increasing amounts of water-absorbent resin. Well-dispersed nanofiller (s) increased the mechanical properties of WSR and prevented SAP breaking off from the elastomer network to effectively enhance the water-swelling durability of WSR.

A better understanding of the adsorption behaviors of hydrocarbons on adsorbent would help trap the hydrocarbons emitted from diesel engines during cold start period more efficiently. In this paper, the adsorption behaviors of hydrocarbons in LTA zeolite was studied using Grand Canonical Monte Carlo (GCMC) simulation. The adsorption isotherms and mass clouds are obtained for both pure component and binary mixtures under certain temperatures. The adsorption isotherms reveal that the average loading of ethylene and propylene has the similar trend. Both of them increase with the increase of pressure and decrease significantly with the increase of temperature. The binary mixtures show competitive adsorption behavior. Propylene is adsorbed much more strongly than ethylene in LTA zeolite. The obtained mass clouds show that propylene distributes in both the α cage and β cage of the LTA zeolite, while ethylene distributes mainly in the β cage of the LTA zeolite.

Currently the development of third-party logistics enterprises in China is facing opportunities and challenges, and urgently needs new management model. This paper discusses the third-party logistics system based on lean logistics from four aspects: lean-agile distribution, value stream analysis, the SLP and information platform construction. This study establishing a new management model provides innovative ideas and methods to third-party logistics enterprises to effectively promote the transformation and upgrading of the third-party logistics business models.

This paper proposes an energy-efficient model to overcome the energy-efficient problem in large-scale IP networks, based on QoS constraints. To characterize network energy consumption, we present a link energy consumption model based on the sleep and speed scaling mechanisms. If there is no traffic on a link, let it sleep, or activate it and divide its energy consumption into base energy consumption and traffic energy consumption. And then according to the link energy consumption model, we can build our energy-efficient model to improve the network energy efficiency. Finally, simulation results show that our model can significantly improve the network energy efficiency.

In this paper, an energy-efficient multicast routing algorithm in multi-hop wireless networks is proposed aiming at new generation wireless communications. Different from the previous methods, this paper targets maximizing the energy efficiency of networks. In order to get the optimal energy efficiency to build the network multicast route, our proposed method tries to maximize the network throughput and minimize the network energy consumption by exploiting network coding and sleeping scheme. Simulation results show that the proposed algorithm has better energy efficiency and performance improvements comparing with the existing methods.

Hydrocarbon trap is an effective way to solve the diesel cold start emissions. Zeolites used as hydrocarbon adsorbents are paid more and more attention. In order to study the diffusion of diesel cold start emissions in zeolites, molecular dynamics(MD) in canonical ensemble are employed to simulate the diffusion of ethylene and propylene in MCM-22 in different ways, the mean square displacement (MSD) plot, diffusion coefficient for pure and mixed components are obtained-. The simulation results show that, propylene (C3H6) and ethylene (C2H4) have different diffusion coefficients in MCM22 zeolite at the same temperature; for the same gas, it also has different diffusion coefficients at different temperatures. In addition, the diffusion coefficient increases with temperature rise, thus temperature rise is beneficial to accelerate diffusion process.

This paper presents a detection algorithm for anomaly network traffic, which is based on spectral kurtosis analysis. Firstly, we turn network traffic into time-frequency signals at different scales. These time-frequency signals hold the more detailed nature corresponding to different scales. Secondly, the time-frequency signals at different scales are transformed into a series of new time signals by time-frequency analysis theory. These new time signals hold obvious narrowband nature and embody the local properties of network traffic. Thirdly, we calculate the spectral kurtosis values of the new time signals and then perform the feature extractions. As a result, the abnormal network traffic can be correctly identified. Simulation results show that our algorithm is feasible and promising.

The metal mine ventilation system is a complex system composed of interactive factors. To get a relative impersonal assessment result of the metal mine ventilation system, the issues, network optimization and program optimization, were discussed and the fuzzy optimization of metal min ventilation system was presented in this paper. Based on the two classic nonlinear programming models for mine ventilation networks, the mathematical model of fuzzy optimization for mine ventilation networks was put forward. A algorithm principle is provided for solving the superior support in a quicker and easier way.

Although, on-off control robot gripper is widely employed in pick-and-place operations, it can not be applied in fragile or soft objects handling. Here, an intelligent gripper is designed with embedded distributed control structure for overcoming the uncertainty of grasped object mass and soft/hard features. An efficient model-free intelligent fuzzy sliding mode control strategy is employed to design the position and force controllers of gripper, respectively. Experimental results of pick-and-place soft and hard objects with grasping force auto-tuning and anti-slip control strategy are shown by pictures to verify this distributed system performance. The position and force tracking errors are less than 1 mm and 0.1 N, respectively.

Through studying the basic principle of super-fluorescent fiber source and combining with internal and external gain flattening technique, the spectral flatness of erbium-doped fiber amplified spontaneous emission (ASE) source with two-stage double-pass configuration pumped by two laser diodes (LDs) is improved. By optimizing the lengths of two-stage erbium-doped fiber (EDF) and adjusting the pump power of two LDs,the powers of C-band and L-band are matching, and the spectral flatness is superior to 0.5dBm from 1535 to 1610 nm. Utilizing the long period fiber grating (LPFG)-based thermally-insensitive gain flattening filter (GFF) fabricated by ourselves, the spectral protrusion is flattened near the peak of absorption wavelength of EDF, which make the spectrum not only cover the range of C-band and L-band, also realize the spectral flatness is better than 0.8dBm in the range of 3dB bandwidth. Application of the fiber ASE source in fiber Bragg grating sensing system could decrease the multi-signal peak power imbalance.

This paper presents an approach of Time-Triggered Ethernet (TTEthernet, TTE) clock synchronization. Firstly it introduces the roles of each device in clock synchronization algorithm, then analysizes the synchronization steps and their two sub-algorithms:permanencealgorithm andcompressedalgorithm. At last it presents the process of clock correction in different devices.

The principium of measuring focus of aerial camera and the location of the actual image plane with CCD camera are introduced, and the methods to improve survey precision are described. The image is received by area CCD camera. The accuracy of orientation of the imaging central line is improved by means of fit the curve method or by center of gravity method. Therefore, the distance between imaging central lines is refinedly calculated. The experimented turn out that the two methods on measuring focus of aerial camera have high precision, and the survey errors are in accordance with the theoretical ones (0.12%). The two methods on deterministic result of the location of the actual image plane are identical, with their precision reaching 100%.

How to select a target network meeting the needs of Quality of Service (QoS) guarantee in heterogeneous network environment has become a research hotspot. In this paper, a novel differentiate weight algorithm on heterogeneous network selection is proposed. As regard of the different needs of QoS for each class of traffic in heterogeneous network, the QoS parameter weight for each class of traffic is calculated by G1 method, and then the target network is selected by technique for order preference by similarity to ideal solution (TOPSIS). At last, simulation results show that the algorithm proposed in this paper is better than average weight algorithm on selecting target network reasonably and balancing network loads.

For safety-designing an equipment/system in civil aircraft, ARP4761 & SAE ARP 4754 is important common standard. But in these standards there has no clear description aircraft structures effect on the equipment/system. In this present paper, aircraft structures effect on design an equipment/system is considered by methods of FHA-FMEA-FTA-SSA quantitatively by conservative assumption. A flow chart of requirement considering structure-support effect is developed.

Because of its good network effect, expandability, technology easy to implement, the trust relay Quantum Key Distribution (QKD) network become future secure communication network preferred scheme. The classification and current status of the QKD network was introduced firstly; then the network model of trust relay network, network channel and key relay mode were put forward. Finally, the decisive parameters which affect the trust relay QKD networks effectiveness and performance were proposed. The simulation results confirm that the trust relay QKD network was used for secure communication is reliable.

In view of present situation of high energy consumption for apparel manufacturers, the reasons for high energy consumption were analyzed in this thesis which tries to explore effective solutions to the mentioned problems. And several different reform programs are presented after feasibility analysis, payback period method and other aspects of comprehensive analysis to identify the most suitable rehabilitation programs for garment production enterprise.

Focal length of lens is an important parameter to determine the relationship between objective and image. It must be measured accurately. The traditional method of using optical bench to measure the focal length of lens has big man-made errors. So we used linear array CCD camera instead of eyes as the receiver to measure the focal length of lens in this paper. Based on the theory of point spread function, it firstly determined the evaluation function of focal plane. With the threshold method, it determined the location coordinate of sharp signal. Then it proved the feasibility of this scheme through experiment. Finally we compared the experimental data obtained with this method with the experimental data obtained with traditional method, which showed that it was more accurate to measure the focal length of lens with this method.

This paper presents an optimization of polysilicon based RF MEMS filter to improve electric isolation and minimize the feed-through, raising the stop-band reject above 20 dB from the original 0.2 dB, and proposes a performance analysis methodology based on polar diagram, which could simplify and visualize the analysis. Intrinsic feed-through of the device is minimized by optimization of substrate in fabrication process, differing from the characterization method reported previously, which is simple and effective.

Through the interpretation of rural environment contiguous remediation documents and the improvement of rural environment contiguous remediation in 2010-2011, we summed up three basic principles of the rural village level wetland sewage treatment system in Wuhan: principle of reaching discharge standard, building education and promotion platform and construction of two-oriented society. It also described some of the cases, and proposed the further elaborated work.

We determined that there are 5 door 35 species of phytoplankton, 6 Galaxy ecological agriculture co., LTD, The average biomass liveweight is 0.6006 mg/l. The reason of less species of plankton and low liveweight of biomass in the system is that the ecological environment of the system is not suitable for general plankton's survival and growth. Therefore, the rural village wetland sewage treatment system has certain inhibition on plankton. On the system engineering designing we shouldn’t consider the factor of plankton.

The effects of EGR operating mode on particulate morphology were investigated for a 5.79-liter diesel engine which was equipped with a turbocharged and inter-cooled air induction system, a common-rail direct fuel injection system, and an EGR system. Morphological characteristics, such as primary particle size, number concentration and aggregate particle size were investigated by a transmission electron microscope (TEM) analysis and a electrical low pressure impactor (ELPI) under engine operating conditions of 0.41 in fuel/air ratio at different exhaust gas recirculation (EGR) rate from 0～35%. The experimental results indicated that primary particle were in the range of 17.05nm～18.34nm, which increased with increased EGR rate. As EGR rate increased, aggregate particle size were measured in a narrow range from 120nm to 170nm.

The revamping & upgrading work has been done smoothly for the old soft-reduction system of the No.4 slab continuous caster in Bayi steel, as a result, all the segments (include both arc segments and level segments ) now have the dynamic soft-reduction function, which have been put into the industrial application successfully. Through the production practice, we can see that, after the revamping project, the dynamic soft-reduction function could be applied normally both in the arc segments and in the level segments for the No.4 slab caster, the whole soft-reduction process has been conducted steady and smoothly, the precision of roll gap control is good, the L2 model always makes an exact trace for the casting process and has the advanced algorithm, the L1 program has the reasonable control function and the reliable execution. When the soft-reduction action was executed in the unbending segment (Seg.7), there was no internal crack taking place for all the slabs, and the internal quality of slab such as center segregation was improved obviously, which had shown the metallurgical effect of the dynamic soft-reduction technology fully.

For the good performance of Double closed-loop DC speed control system, it is widely used . When the motor are selected, the parameters of the system can not be changed. Then,the system performance can only be improved by changing the parameters of the inner ring current regulator and outer ring speed regulator of the double-loop DC converter system. This paper studies mathematical modeling and system simulation of Direct Current Governor System on Matlab simulink platform. The simulation method, can adjust the system controller parameters flexibly, so as to achieve the ideal design results, and the design of the system are analyzed, the optimal "parameter range" is found, It can save the time of system development,and improve the standardization degree of system design.And the simulation results of the system can provide primary plannings and guidances for the actual system design,thereby lower the design cost of hardware largely, enhance the accuracy of hardware installation.

In this paper, fast algorithms for computing composite-number-less-than-20-point DFT is developed, it is based on the matrix operation, makes as much use of the characteristics of twiddle factor, repeatedly transforms the twiddle factor matrix, finally, the core matrixs for computing N-point DFT is obtained. This paper provides the core matrix, calculation process and the amount of computation of less-than-20-point DFT. The algorithm is easy to be understood and applied.

This article has systematically summarized the recent research situation of control rod system in China and comparatively analyzed the features of a variety of control rod drive systems on a basis of brief introduction of common types of control rod drive system. It has been proposed to that the hydraulic control rod drive system have a great potential in a wide application concerning on ships, warships power reactors and protable desalination system.

Used A/O-SBR(anaerobic/aerobic alternating enhanced biological phosphorus removal system) to study carbon source and phosphate accumulating organisms (PAO) intracellular energy storage substance transformation, also studied PAO’s phosphorus removal capacity. PAO could uptake quick degradation organic matters and synthesis polyhydroxyalkanoates(PHA). PHA was a kind of intracellular energy storage substance, its content could affect PAO’s phosphorus removal capacity. When carbon source was plentiful, PAO could synthesis a lot of PHA, phosphorus removal capacity could reach 38.16 mgp/gvss. Sludge retention time could affect PAO synthesis PHA of quantity and structure. Along with the sludge retention time growth, intracellular PHA content was increased, and phosphorus uptake of desired aerobic time continues to decrease, so increasing the phosphorus removal efficiency. When the municipal sewage as carbon source, PHA was mainly composed of PHB(poly-ß-hydroxyvalerate) and PHV(poly-ß-hydroxyvalerate). Along with the sludge retention time prolongation, PAO could synthesis more PHV, PHB content was remain unchanged, PHA composition structure was changed.