Search

Dynamic collapse analysis is an important research subject for large span single layer reticulated shell structures. In this paper, the dynamic collapse behavior of the single layer reticulated shell with substructure which support the reticulated shell are investigated under the earthquake actions. In the analysis, the geometric imperfections, the material and the geometric nonlinear of the structures are considered. The effects of different stiffness of substructure to the collapse earthquake accelerations and the plastic member distribution of the reticulated shell are investigated.

Vinyl acetate, as an important kind of organic chemical raw materials, often adopts the distillation system to separate finished product from raw product. In addition to target products, some residues are produced in the process of distillation, which have a strong damage to the environment, therefore these residues are identified as hazardous wastes to manage and dispose in China. This paper, combined with literature analysis and site investigation, mainly studied production characteristics and particular pollutants of vinyl acetate distillation residue (solid and liquid). To conduct the analysis of the physical and chemical properties of distillation residue, and this paper applied the Gas chromatography-Mass spectrometry (GC-MS) to detemine main particular pollutants, containing Acetic Acid (relative peak area value of 63.47%), 1,1-Ethanediol Diacetate, Crotonic Acid, etc. Meanwhile, this paper can draw another conclusion that treatment and disposal of resource utilization distillation can make more significantly and efficiently use of vinyl acetate distillation residues through the technological contrast of GC-MS.

The operating range of ground-based detector on hypersonic vehicle in rarefied atmosphere space is researched. Both the imaging dispersion and the difference of radiation intensity between object and background are considered, and a new model of operating range is proposed. By experiments, the dispersion coefficient changes with the distance between object and detector and has great effect on operating range; meanwhile, the higher the velocity of vehicle is, the further the operating range is. And the detector working at medium wave infrared has larger operating range. Compared with existing method, the proposed algorithm achieves better result in the field experiment.

Based on the application of aerial images processing technology and 3D visualization technology, this paper used a series of procedures including aerial images procession, DEM generation, three-dimensional tower modeling and images recombination, and adopted VB + VRML to generate virtual three-dimensional images animation of the study area according to certain scale and flight routes, this three-dimensional power lines selection system provides the designers the most direct information to grasp the route of the transmission lines from the macro perspective.

In order to measure capture performance of the seeker in the typical terminal guidance scene under HPM damage effect, the paper proposes a new method to model the dynamic capture state in different ballistic position. The proposed missile-target geometry count can be used to process multiple data generated in multiple Monte Carlo simulations under the same scene, which facilitates capture performance comparative analysis between different scenes. Simulations validate proposed counting measure, so that it can be applied for measuring the performance of missile capture.

Strong earthquake motion observations have gathered much useful data for the seismic-resistant design of civil engineering structures, and for developing earthquake prevention technology. The performance of Chinese strong motion network has been evaluated from recent earthquakes in Chinese Mainland. To follow the new requirement of the earthquake mitigation plan, some new practice of strong motion observations are described, including rapid urban ShakeMap, earthquake early warning system.

In order to switch line protection to bus coupler protection when bus coupler circuit breaker is in place of by pass state for line bay efficially and reliable, according to experience of Chinese substation building. this paper presents 3 switch modes. At last, reference with the habits of Zambia , this paper presentsone better mode for Zambia substation through comparing the effectiveness and reliability of the 3 switchmodes.

In order to meet the technical production requirements of the ammonia modification equipment, this paper develops a set of electrical control system based on Omron CJ2M Series PLC, including the configuration of the hardware and software, the assignment of the input/output, and the design of communication system. The control system provides a perfect human-machine interaction and realizes the automation control of the devices.Through actual application, this control system can meet the control requirements of the ammonia modification production and raise the production automation level of the factory and increase labor productivity.

A new technology of lattice distortion modification of cotton/linen fiber and yarn is introduced in this paper. The process parameters and control requirements in the lattice distortion modification processing are analyzed for designing its control system, The hardware system is designed using the Omron PLC as control core and the human-computer interaction interface is built by using configuration software. At last, a real time accurate program on fuzzy compensated decoupling control of the temperature and pressure in the modification process is presented. The test production results show that the control system designed totally meets the production requirements of the lattice distortion modification of cotton/linen fiber and yarn.

For the large air bearing capacity and high rigidity, the author put forward a kind of slit type guide rail which based on gas film clearance throttle,through establishing the guide physical model,fitting the gas film surface ,and building a flotation control equation, refering to the finite difference method and dichotomy,solved the gas film pressure distribution based on Matlab numerical calculation,analysed the bearing capacity of gas floating needle bar under different eccentricity and the stiffness.The results show that: the gas floating guide,if a slit’s width is 0.2 to 0.26,and the cumulative length of the slit for half of the perimeter of the inner surface,the slit intermittently arrange six along circumference,has the best static performance.The larger the needle bar eccentric,the bigger the flotation capacity and stiffness,it is capable of carrying the load of the needle bar,and the air tightness of the structure is good,throttling effect is obvious.

Toxaphene is an organochlorine insecticide, widely used in cereals, vegetables, fruits, tea and other pests. However, in killing pests, increasing agricultural production, while toxaphene aquatic creatures threat. In order to enrich aquatic organisms toxicological data, evaluate the risk to aquatic organisms toxaphene healthy growth, we use the traditional toxicological approach to study the toxic effects of toxaphene goldfish (Carassius auratus)'s. Study 5 toxaphene concentration 7d goldfish exposed catalase (CAT), superoxide dismutase (SOD), acetylcholinesterase (TChE), glutathione peroxidase (GSH-PX), malondialdehyde (MDA) effects, the results showed that: toxaphene in 0.1,0.2,0.3,0.4, 0.5 μg / L in five concentrations, these five enzymes promoting effect, with more toxaphene concentration high, goldfish liver CAT activity is stronger, the stronger the brain and liver SOD activity, the activity of the brain TChE weaker, the stronger the brain activity of GSH-PX, and the contrast with the blank, P

The bis-type quaternary ammonium salts (bis-QAC) with hydroxyl group in their molecules, 4,5-Bis (alkyl dimethyl ammonium bromide)-1-pentanol were immobilized on cotton fiber to prepare an antibacterial cotton fibers (called as Ws) by using a coupling agent, tetramethoxysilane. The antibacterial characteristics of Ws were investigated. 4,5-Bis (alkyl dimethyl ammonium bromide)-1-pentanol chemically bonded to the surface of cotton fiber exhibited antimicrobial activity against a broad range of microorganism. Their antibacterial activity was not easily influenced by environmental pH and temperature, and could not be removed from the surface of wool by repeated washing.

As the “fifth facade”of building,roof is one of the approaches to promote sustainable urban development for its advantages.This paper demonstrates the benefits of roof greening on living conditions and energy efficiency,puts forward some advisements about combining the application of roof greening technology with Geography and climate,pursuing the accordance in nature ,economy and resources.

The key-stream generator is the most important algorithm component of the stream cipher and the security of the stream cipher is based on the property of the key-stream generator. At the present, it is still an important development direction of the stream cipher algorithm that the high performance key-stream generators are constructed with complex block cipher algorithms. This paper puts forward the new type of the key-stream generator based on the AES algorithm. This method is based on the OFB mode of the AES algorithm, combined with the variable-step feedback shift. Then the paper analyses the randomness of the key-stream produced by the new key-stream generator. This new key-stream generator really improves the cryptographic properties of the key stream generator and to enhance the security of stream cipher effectively.

The supervision monitoring program for radioactive effluent of nuclear power plants is an important basis of the radioactive effluent monitoring work. The general review principle of the supervision monitoring program is discussed in this article, and review suggestions of monitoring, evaluating and quality assurance are also given by focusing on requirements of technical details about key elements such as monitoring projects, sampling and monitoring points, frequencies and low limits of detection. For the supervision monitoring work of radioactive effluent of nuclear power plants, it can provide some guidance about the review of the supervision monitoring program for nuclear safety regulators, and provide some reference about the design and revision of the supervision monitoring program for nuclear safety monitoring departments.

This paper provides a method of multi-sensor data detection and fusion, aims to resolve the data measurement inaccurate problem in the process variable control system of the ammonia modification equipment. First, it establishes the sensor data measurement model and calculates mutual support level of the multiple sensors, using boundary value judgment method to produce the multiple-sensor mutual support level matrix, the total number of mutual support level for one sensor in the matrix is the weight value of this sensor, and finally the normalized weighted average data fusion (NWADF) method is used for data process.Experimental results show that the proposed method for multi-sensor data fusion can effectively be used to identify the abnormal data in multi-sensor measurement system and improve the accuracy and stability of the process variable data measurement.

The direct laser drilling could bring the recast layer and micro cracks, here introduced a new method named low-pressure water jet assisted laser drilling.It mainly studied some factors influence on the surface and inwall morphologies of Al2O3 ceramic when using low-pressure water jet, such as auxiliary gas pressure、pulse energy、repeated frequency.By optimizing the parameters, it can get the better surface and inwall morphologies. The results show that, taking advantage of the erosion of water jet, the composite drilling can obviously lessen molten slags, in order to reduce the recast layer and micro cracks, the processing quality can be improved much.

The paper first analysis a part of the existing subway station entrance of the form, and then combined with the Zhengzhou University (South) design of the subway station entrance, explores new forms of the subway station entrance to ETFE materials based on, and introduces some applications of new forms of expression effect and modular in the design of this kind of practice, not only for the subway station entrance to create new forms, but also the "ETFE" membrane using a good try in a small building, promote the new development of this kind of materials.

The phenomenon of ghosting fire development in underground confined space is simulated to analyze the impacts of ghosting fire generation via some conditions -- different air vent sizes and different fire source areas. FDS is used to establish a physical model of underground fire laboratory in Northeastern University, the simulation is conducted by setting two parameters, the air vent size and the fire source area. The fire heat release rate, temperature, concentration of CO, O2 are measured to analyze the case of ghosting fire generation in underground confined space with different air vent sizes and different fire source areas. It’s most likely to generate ghosting fire when the simulating parameter is that the air vent size is 0.4m × 0.4m and the fire source area is 0.96m2. The conclusion is that increasing the air vent size is not a simple ascending and descending relationship with the occurrence time and duration time of the ghosting fire. Increasing the fire source area can improve the fire heat release rate effectively, and promote the formation of ghosting fire.

This paper introduces a new-type alkali-free and chlorine-free high performance liquid accelerated admixture. The accelerated agent is mainly composed of the following components: fluoride magnesium aluminum silicate is main accelerator, alcohol amine polymer is activator, and amide polymer is stabilizer. When dosage of the admixture is greater than 4%, the cement initial setting time is less than 5 min, the final setting time is less than 10 min, and the 28 day compressive strength ratio of mortar is more than 100%. The mechanism is the accelerating of agent on hydration of C3A and C3S. There are large hydration calcium flu silicate (11CaO·4SiO2·CaF2) and hydration calcium aluminates at the later stage of hydration.

A long-span cable-stayed arch bridge is a new form of bridge structure that combines features of cable-stayed bridges with characteristics of arch bridges. In the present study, we derived a practical calculation method for the lateral destabilization critical loading of cable-stayed arch bridges during the construction process based the energy principle. The validity of the method was verified with an example. The calculation method provides a quick and efficient way to evaluate the lateral stability of a cable-stayed arch bridge and a concrete filled steel tubular arch bridge during the construction process.

The key-stream generator is the most important algorithm component of the stream cipher. At the present, it is an important development direction of the stream cipher algorithm that uses complex block cipher algorithms to construct high performance key-stream generators. The paper puts forward a new design method of the key-stream generator based on the AES algorithm. This method is based on the CFB mode of the AES algorithm, combined with the variable-step feedback shift. Then the paper analyses the randomness of the key-stream produced by the new key-stream generator. This new key-stream generator really improves the cryptographic properties of the key stream generator and to enhance the security of stream cipher.

Fully developed turbulence single phase convection heat transfer of water in pipes filled with sintered porous metal inner rings or solid inner rings was investigated numerically respectively. Numerical calculations were conducted with the Fluent 6.3 code, using the SST k-ω turbulence model. Comparing to solid-ring turbulator pipes, porous-ring turbulator pipes have better comprehensive heat transfer effect. The maximum PEC for porous-ring turbulator pipes is 4.4 and the PEC of solid-ring turbulator pipes is less than 1. It was also analyzed effect of geometric structures on porous-ring turbulator pipe performance. f/f0 for porous-ring turbulator pipes increases with the increasing of Re while Nu/Nu0 decreases with the increasing of Re ,and PEC decreases with the increasing of Re. With the same Re, if the width of the porous ring is equal to the width of groove, f/f0, Nu/Nu0 increases and PEC decreases with the increasing height of porous ring. When the height of porous ring is constant, the f/f0, Nu/Nu0 and PEC decreases with the increasing height of porous ring under the same Re.

IEEE1394 is a high performance serial bus, which physical layer directly to transmit and receive data with other nodes. when the ports of physical layer connect to other nodes, The connection which is not allowed may be activated. so there may be a loop formed in a bus topology ,which may influence the normal work of system. This paper analyzes the causes of the physical layer interface to form a loop, and introduces the method of port loop detection.

Semiconductor manufacturing is a capital-intensive and high-tech industry. In order to reduce production cycle time and increase production flexibility, the semiconductor manufacturers will expand the capacity in the existed fab and build up new fabs. However, the expandability of production capacity is not infinite since the huge fab scale will increase risk of production management. Therefore, it is necessary to find out the factors which will influence the performance of fab scale. This research uses the eM-plant simulation software to construct a simulation environment to conduct simulation experiment. The experimental environments were divided into two parts and named as high and low product mix complexity separately. Furthermore, three more factors were taken into accounts, which included stability of machine, variation of fab scale and releasing rate. By simulation, the analytical data is collected and analyzed its trend in these different environments. Simulation results reveal the significance of factors under different environments. Based on these results, the managers can conclude an appropriate fab scale in giga-fab, which will help to reduce the cycle time of products and increase the total throughput of giga-fab.

In this research, a model of production planning among different phases is developed. Although every phase at same giga-fab should be regarded as the similar. However, due to the different installation time, technology level and capacity allocation, the production capability of each phase will be distinguishing. Therefore, the major purpose of the production planning model is to develop a feasible and easy used algorithm to fully utilize the capacity of each phase under constraints. The concept of DBR scheduling is applied in this model to fulfill the major target. Furthermore, the notion of Technology Turn Rate (TR) is used to calculate the required date of capacity constraint resorce (CCR). Based on the prefercnce phase of products and the status of CCR, the release phase and date of each order can be well arranged.

This paper studies the lean burn limit characteristic of the compound injection system of the direct-injection gasoline engine. The low pressure nozzle on the intake manifold can achieve quality homogeneous lean mixture, and the direct injection in the cylinder can realized the dense mixture gas near the spark plug. By adjusting the two injection timing and injection quantity, and a strong intake tumble flow with special shaped combustion chamber, it can produces the reverse tumble to form different hierarchical levels of mixed gas in the cylinder. Experimental results show: the compound combustion system to the original direct-injection engine lean burn limit raise 1.8-2.5 AFR unit.

An novel decoupled estimation algorithm based on kalman filter is presented to solve the line-of-sight (LOS) rate estimation problem in terminal guidance of air-to-air combat. The measurements of target azimuth and elevation are obtained by missile-borne active radar seeker which use a monopulse doppler radar. As it cant be directly measured by this kind of radar, the LOS rate which is needed as the input of guidance law should be estimated from these angle measurements. The close-loop simulation of LOS rate estimation in typical terminal guidance scenario that an air-to-air missile seeks a military fighter validates the presented algorithm.

The performance of a solar-driven air-cooled ejector refrigeration system using ammonia as refrigerant with rated cooling capacity of 10.5kW was analyzed for air-conditioning purpose. The cooling capacity of the proposed system increases with the rising of indoor temperature and enhancement of solar irradiance, while decreases with the rising of outdoor temperature. The COP has similar changing trend with that of the cooling capacity except that it increases rapidly with the enhancement of solar irradiance firstlyand then become stable by and large after solar irradiance exceeding a certain value. The cooling capacity is 6.3~52kW and the COP 0.06~0.11 under the normal operating conditions with indoor temperature over 27, outdoor temperature below 38°C and solar irradiance surpassing 500 W/m2. The proposed system can match the climatic conditions in air-conditioning season of Nanning, a typical city in hot summer and warm winter region.

The C90 high performance concrete was prepared with crushed cobblestone, washed riverbed sand, special mineral admixture. The crushed cobblestone was crushed from cobblestone which particle size was larger than 160mm. The crushing quality coefficient of the cobblestone was above 80%. The gradation of the crushed cobblestone must accord with 5-20mm continuous grading. The compressive strength of HPC90 was above 40MPa in 1d and 103.9MPa in 28d. At the same time, HPC90 had good ability in anti-crack, impervious and anti-freezing-thawing performance.

In order to grasp the whole growth process of breeding cotton and establish the growth records of breeding cotton, the article proposes the design of breeding cotton growth management system based on MMS. The main idea is that field image acquisition terminals capture a live image in breeding cotton plots at a specific time every day, and send the live image to the monitoring center through the GPRS networks, then breeding cotton experts write cotton growth log and propose the next management advice for cotton based on the returned live image. At the same time, all the information will be written to the database in the monitoring center. The application of the system is able to not only save manpower costs, by tracking and analyzing the whole growth process of breeding cotton, but also summarize the successful breeding experience and failures. At the same time, the application of the system promotes cotton breeding and cotton management more scientific. After the actual testing, the system works stable and reliable, and meets the design requirements.

Tube has a complex structure in space, in order to machining tubes of different radius and avoid interference, a new type of Triz bending machine is developed, which has up to eight dies by moving and rotating the head of the machine. The key technology of tube coordinates transformation is solved by the vector algorithm. For the springback problem, a compensation is add to the final working parameters, which can reduce the testing time and the quantity of scraps. Finally the tube bending simulation system for the new machine is developed based on Visual Studio 2010 and Open GL.

In this paper, we present an improved text clustering algorithm. It not only maintains the self-organizing features of SOM network, but also makes up the disadvantages of the bad clustering effect caused by the inadequate selection of K-means algorithm. Firstly, data is preprocessed to form vector space model for subsequent process. Then, we analyze the features of original clustering algorithm and SOM algorithm, and plan an improved SOM clustering algorithm to overcome low stability and poor quality of original algorithm. The experimental results indicate that the improved algorithm has a higher accuracy and has a better stability, compared with the original algorithm.

A test system for subsea tree equipment is developed for tree function testing after repair. The test system mainly consists of hydraulic unit and electric unit. The hydraulic unit is developed by revamping an old hydraulic power unit, which consist of six components, including reservoir, flush/fill pump circuit, high pressure hydraulic pump circuits, accumulator group, hydraulic supply circuits and fluid return circuit. The electric unit for subsea tree is developed by using NI Compact DAQ system, In order to control the hydraulic unit and acquire the pressure signals easily. The test procedures for flowloops, valve, and hydrostatic hydraulic pressure cycling are proposed based on the factory acceptance testing of subsea tree. A test for a repaired subsea tree is performed by using the developed test system. The results show that the repaired subsea tree is good enough after repair, and verify that the developed test system works well.

In order to establish and improve the radiation environment monitoring standard system, to provide technical support for the radiation environment monitoring system, this work first retrieve the radiation environment monitoring standards, and clear the domestic status of the radiation environment monitoring standards. According to environmental Protection Department of the relevant documents and other relevant information, the radiation environment monitoring standards and methods have been accessed , to find the missing items and issues proposed revision of the system requirements. Summarizing radiation environment monitoring national standards, standards of environmental protection industry, the nuclear industry standard, there are 28 standard missing items need to the health industry standards, inspection and quarantine industry standards, a total of 145 of these standards of environmental radiation monitoring, radiation monitoring of pollution sources, emergency response and early warning and monitoring from a management and technology meet the basic needs of the radiation environment monitoring. Research found that the standards in the revised 57 and in the formulation of 47, develop. After the revision of China's standards system will be further improved. The radiation environment monitoring work will be further strengthened.

One of the main geological disasters in Wuhan City is karst surface collapse. Analytically the main elements affecting karst collapse contain Karst development, covering layer condition and hydrogeological condition. This paper aims to set up the risk zoning evaluation model about this disaster upon BP neural network theory. And then evaluate the risk zoning of karst collapse. The assessment result shows karst surface collapse of high risk in Wuhan City mainly distributes in Ruanjia Lane, Lujia Street, Justice School, Fenghuo Village,Zhongnan Steel Mill and Maotan Harbor.

Rule acquisition is a hot topic in the field of data mining. And the inconsistent information systems are widespread nowadays. However, rules acquisition methods are always the difficulty of rough set theory application in inconsistent decision information systems; So the paper proposes a new rule acquisition method. Firstly, we use maximum distribution reduction method for knowledge reduction in single decision-making inconsistent information system and then we use decision-making resolution matrix and decision-making matrix function to get the decision rules. Finally, we mine the rules from inconsistent decision-making information systems.

This paper introduced a new mechanical construction for the vibration platform and its working principle. Based on virtual instrument, this paper used sensor, charge amplifier, DAQ(data acquisition card), computer, driver program and LabVIEW software to design signal measuring and analysis system of mechanical vibration platform. This paper used ADAMS simulate vibration platform motion and used LabVIEW calculate distortion degree of acceleration, velocity and position of the vibration platform.

The fastening is an important part for fastening when laying the rails, which requires sufficient fastening pressure, strength, and durability. This article focuses on the fatigue fracture of the spring clip of a fastening and gets a result that the fracture accounts for alternating twist-bend load by examining macro-fracture. The crack origin is on the surface of the clip where significant decarburization and corrosion exists and its extension makes the clip break by examining metallographic structure and testing micro-hardness. The solution is to improve the heat treatment method and the surface quality avoiding corrosion.

In the modern wars under the condition of informationalization, radar signals are generally characterized by repetitive patterns in time, so it is one important task of Radar Warning Receiver (RWR) to estimate the Pulse Repetition Interval (PRI) of all radar signals by intercepting and identifying the mixed radar signals. Because each transmitted radar signal are arbitrary in general. From the view of statistic, the transmitted radar pulse train from different radars is mutual independent. So the constituted model of RWR and radar transmitters accord with blind source separation which can separate mixed signals into pure signals. A deinterleaving method using blind source separation for estimating the PRI of each radar signals is proposed. The implementation architecture of the proposed method is given. Finally, computer simulations show the proposed method can gain good performance for the estimation of PRI of radar signals.

The calculation equations of soil-column area replacement ratio (m) recommended by Chinese code Technical Code for Ground Treatment of Buildings (JGJ79-2012) have many limits in the practice. In this document, general equations of m value are derived by subdividing the composite soil element under the different pile arrangements. The results show that m value is determined by the two parameters: interval number among piles (n) and pile diameter-spacing ratio (d/s). m value greatly decreases with the increase of d/s at the constant n, whereas m slightly decreases with the increase of n at the constant d/s, and the larger n, the smaller drop of m value. Under triangular pile arrangement, the Chinese code recommended equations can be used with less than 10 percent of error ratio of m value when the width of composite foundation is above 10 m, but the general equations should be applied when the width is below 10 m. Under square pile arrangement, the recommended equations can be used when the width of composite subgrade is above 15 m, but the general equations should be applied when the width is below 15 m. The general calculation equations of m value derived in this paper can provide certain reference for theoretical calculation and engineering application.

In order to solve the attitude synchronization control problem for an on-orbit servicing spacecraft autonomous docking to a tumbling satellite in the presence of unknown bounded disturbances and system uncertainties, a compound control law is presented in this paper. The compound control law is composed of a nonlinear feedback control law and a compensate control law. The nonlinear feedback control law is mainly used to track the system command and the compensate control law is mainly used to deal with the external disturbances and system uncertainties to enhance the robustness of the control system. Simulation results verified the effectiveness of the designed compound control law, and the robustness to the unknown bounded disturbances, system uncertainties is also demonstrated.

Symbolic-code condition mutual information (SCCMI) algorithm is proposed,which can detect coupling between several systems.SCCMI combines condition mutual information with symbolic-code algorithm. Condition mutual information entropy is used to finding coupling degree between time series .The meaning of symbolic-code algorithm is to retention large scale information of time sequence, whats more ,reduce noise effect. SCCMI algorithm is used to analyze difference of coupling between epileptic EEG signals and normal ones .Hypothesis testing was done by SPSS.It turns out that the difference between epileptic EEG signals and normal ones is significant.SCCMI algorithm is proved to be effective. And coupling degree can be used as a parameter to measure if brain is healthy.

A study on C80 high performance concrete used in deep freezing mine shaft liner is made. Test results are listed as follows: (1) Concretes compressive strength at 1 day is 53.0 MPa, while the compressive strength at 28 days is 93.5 MPa. (2) The diffusion coefficient of chloride ion at 28 days is 9.8×10-14m2/s, and freezing-thawing cycle is over 1000 times. The evidence above proves that this concrete can satisfy the requirements of C80 high performance concrete used in freezing shaft sinking techniques.

Collaborative filtering is regarded as the most prevailing techniques for recommendation system. Slope one is a family of algorithms used for collaborative filtering. It is the simplest form of non-trivial item-based collaborative filtering based on ratings. But all the family of use CF algorithms ignores one important problem: ratings produced at different times are weighted equally. It means that they cant catch users different attitudes at different time. So in this paper, we present a new algorithm, which could assign different weights for items at different time. Finally, we experimentally evaluate our approach and compare it to the original Slope One. The experiment shows that the new slope one algorithms can improve the precision

Achieving the monodispersion of Multi-walled carbon nanotubes (MWCNTs) is a challenging work for CNTs application. Centrifugation as a standard procedure was employed to remove remaining large bundles and leaving primarily individual nanotubes and small bundles in the supernatant. The optimum centrifugation time and force were 30min and 12×103g, respectively , which were determined by UV-vis absorbance, transmission electron microscopy (TEM), Zeta potential and the residual MWCNTs concentration after centrifugation. Through centrifugation treatments, the uniform and stable MWCNTs monodispersion can be obtained and the Zeta potential was as high as-53.8mv after one month. The film formed from optimized MWCNTs monodispersed solution is smooth and flexible.

By making use of water as the sensitizer for triethylaluminium explosion, the contrast test was designed for dispersion of triethylaluminium explosion in water and air. It was observed by the high-speed photography that that triethylaluminium was burning and dispersing in air at a maximum dispersion speed of 27m/s, while triethylaluminium was mixed with water, the dispersion speed reached 60m/s. The range of flame was larger than in air horizontally and vertically. The test results show that the triethylaluminium sensitization was significant. After the test ended, the clear deformation of aluminum basin could be seen, which indicated overpressure occurred in the process of reaction between triethylaluminium and water. The contrast test of triethylaluminium explosion was performed in two cases of 50L and 30L water. The test result shows that appropriately increasing quantity and diameter of water facilitates detonation.

The classical approaches using CFD software to calculate the hydrodynamic performance of catamaran planing vessel still need to rely on the model test or empirical formula to make sure of the running attitude. So a theoretical calculate method of resistance performance of catamaran planing vessel is proposed in this paper based on RANS equations and the VOF method to couple six degrees of freedom equation of the catamaran planing vessel. Numerical simulation results indicate that using RANS equations can better forecast hydrodynamic performance of catamaran planing vessel at high speed, which provides a practicable numerical method for optimization design of the catamaran planing vessels hull.

it is hard to establish the accurate model by using the traditional PID algorithm, and hard to adjust the system parameter in nonlinear system. In order to solve this problem, this paper proposed PID algorithm based on Fuzzy Neural Network. This algorithm combined PID algorithm, fuzzy control algorithm and neural network algorithm together, and formed one kind intelligent control algorithm. This paper designed and researched this algorithm, and applied in the PLC temperature control system. The experimental result indicated that the fuzzy neural network PID controller improved the controller quality, conquered some question such as variable parameter and nonlinear, and enhanced the systems robustness.

Due to the special hull shape of the catamaran planing vessel, the shiplines optimization design and the hydrodynamic performance prediction of the catamaran planing vessel are mainly carried out by model tank tests and the empirical formula at present. The numerical prediction method of the hydrodynamic performance of catamaran planing vessel has been a big difficulty for a long time. In this paper, the influence of the key channel design parameters on the catamaran planing vessel hydrodynamic performance is studied based on the CFD technology. Some beneficial conclusions are obtained which is helpful for the optimization design of catamaran planing vessel. The work of this paper provides a numerical research method for the optimization design of the catamaran planing vessels hull.