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Three types of low-carbon TMCP steels with different strength of the same carbon equivalent were welded by the flux-cupper back for SAW(FCB) method in this work. The microstructure, hardness and tensile strength of the FCB welded joints were studied. Softening phenomenon occurs in the heat affected zone of low-carbon content and low carbon-equivalent TMCP EH36 steel after high heat input welding. The softened zone is mainly depended on the strength of the base metal (BM), which appears on the fine-grain zone and incomplete crystallize zone of BM with relative low strength, and on the coarse grain zone of BM with high strength. The ratio of the tensile strength between each FCB joint and BM is the same of 0.98 as the same carbon and carbon equivalent content of 0.5% and 0.315% of BM, which is almost independent of the strength of BM. The tensile strength of the incomplete crystallize zone depends on the strength of the BM, which results in the improved strength of the whole softened zone with the increasing strength of base metal.

Due to the lack of data about special windy or rainy day weather and the abnormal change characteristic of load, this paper proposes a new sensitivity analysis method between load and meteorological. Firstly, a method is put forward to select the factors affecting the load based on grey theory to calculate the correlation coefficient. Secondly, the multiple linear regression relationship between load and weather according to the meteorological conditions in different intervals is built to get more accurate sensitivity between load and meteorological factors. Finally, an example is used to reveal the law of load changing with weather in Haikou power grid. The result shows that the proposed method has a practical reference value for improving power grid load forecast accuracy and operation safety in the typhoon and other special weather conditions.

A novel indoor positioning algorithm named BPNN-LANDMARC is proposed in this paper to increase the positioning accuracy and reduce the high time complexity of classical LANDMARC algorithm. Simulation results prove that the proposed BPNN-LANDMARC algorithm can improve the average positioning accuracy by 24.35%. In addition, the improved algorithm reduces the time complexity of algorithm obviously.

The gas-burning boiler fume condensing technique is studied so that the boiler fume can be cooled, a lot of vapor in the fume can be effectively condensed, potential heat in vaporizing can be recycled to improve the boiler heat efficiency and control the pollutant emission.

In traditional Bayesian classification data mining methods, there may be defects such as predictions unreliable because the selected predictors are little or not related with the target factor. this paper analyzes the correlation between predictors and the target factor using correlation coefficient based on Bayesian classification model and combines with Hadoop distributed file system and parallel programming models to explore an improved algorithm. The experiments show that this method not only makes the prediction more reliable but also saves resources and improves the efficiency of the algorithm greatly. In addition, it is suitable for massive data processing.

The paper discusses how to use the advanced technology of the Internet of things to realize the real-time monitoring of the library and the preservation of goods in transit third party cold chain logistics, mainly discusses how to network technology with Internet 3G network of RFID and WSN integrated network and intelligent nodes, realize the visualization of fresh goods real-time monitoring, convenient management personnel of customer inquiries and feedback information, to ensure the preservation of food quality and safety.

Harmonics always have a negative impact on control precision and grid quality. It has been found out that harmonic distribution is very germane to carrier frequency. Based on the analysis of conventional SVPWM, in this paper a chaotic carrier frequency SVPWM strategy is proposed, where the theory of chaos is applied to generate the desired random source for SVPWM carrier frequency. Simulation result proves that chaotic carrier frequency SVPWM can not only improve the waveform quality, reduce the low-order harmonics, and also flatten the high-order harmonics effectively.

In order to more effectively classify the science and technology intelligence text, the idea that classifying science and technology intelligence text categorization based on different classifiers is proposed. The experiment is done with two thousand Chinese texts based on three different classifiers in this paper. Among these classifiers, the rate of correctly classified instances with NaiveBayes Classifier is 96.95 percent and J48 Classifiers is 97.59. The highest of three classifiers is SMO Classifier and its correct rate is 98.65 percent. According to the analysis of experimental results, it is proved that the idea proposed is applicable to science and technology intelligence text categorization and it is able to meet the needs of text categorization.

in order to understand the situation of design flood level, a water level monitoring system based on ARM7. The ARM7 high performance microprocessor LPC2132 as the core, uses the high precision AD converter TLC2543 data collection, combined with the system software and hardware design of GPRS transmission network, including the water level sensor data acquisition, remote transmission of GPRS messages, human-computer interaction module C/OS-II operating system with multiple components, the system design, to achieve the level of information the remote communication by using short message. The experimental results show that: the system to collect data of high precision, stable and reliable transmission, effectively realizes the real-time monitoring of water level data.

In hot rolling process of 2205 duplex stainless steel, it was found that bright line defects are mainly located at where is about distance of 200 mm from two sides of hot rolled plate. The forming reason of bright line defects is studied by means of metallographic microscope, scanning electron microscope (SEM) combined with energy dispersive spectrometer (EDS). It is concluded that the formation of bright line defects has associated with sticking and that the temperature reduction on the edge of hot rolling plate causes a high percentage of austenite phase which is network structure. In order to prevent or avoid the happening of the sticking phenomenon, it is necessary to uniformly distribute the oxide on the strip surface by controlled rolling process.

This paper describes a portable food can be several key techniques in the design of electronic balance. First introduced the electronic balance control planning and power in the hardware design. Then analysis system software development process, and gives the software method to reduce system power consumption, and improve the system operation speed by adjusting the position of software code. The scheme of the embedded network communication system, for consumers and food operators to provide a friendly interface, service, humanity has the advantages of simple operation, low power consumption, good portability, meets the requirements of food traceability and food supervision.

Based on the principle of the ISO14042 standard on life cycle impact assessment, the paper uses the environmental eco-indicators to evaluate the environmental impact of waste electrical in reverse logistics. Firstly, build environmental impact indicator system based on the method of eco-indicator99, and use rough set theory to calculate the weight of all the indicators. Then combine the weight with eco-indicator99 database to calculate the environmental eco-indicators. Finally, take waste refrigerator for example to illustrate the process of environmental impact assessment of general waste electrical.

Modern composite armor plate is generally composed of faceplate with high hardness and backplate with good toughness. 45 steel/60Si2CrA multilayer composite casting blank with 11 layers, containing 60Si2CrA steel as faceplate and 45 steel as backplate, was fabricated by composite casting. The deformation and heat treatment process of 45steel/60Si2CrA multilayer composite plate were studied. The results show that the interfaces between faceplate and backplate have good combination and the thickness of each layer is basic uniform by reasonable deformation distribution. Yield and tensile strength of the composite plate reaches 956MPa and 1018MPa, the hardness of 45 steel layer and 60Si2CrA layer is 448HV and 536HV respectively after the heat treatment of 860°C water quenching+ high temperature tempering. The mechanical properties meet the qualification of armor plate. The bulletproof test displays that 45 steel/60Si2CrA multilayer composite armor plate can prevent the breakthrough of DAP51B type bullet with the velocity of 500m/s.

The ball screw is a main driving component in the CNC machine tools. The ball screw’s structural performances and working conditions will have an important impact on the machining accuracy of CNC machine tools. However, the previous research method can not suffice the precise results’ requirements. So it is very necessary to do an in-depth analysis of the ball screw, which use dynamic research and be combined with the FEA software ANSYS. This article uses the above methods to do the modal analysis, and then gets the intrinsic frequency and the vibration model. It will make an important significance for guiding the practice.

Very high frequency (VHF) is widely used in radio and television broadcasting. In order to improve the quality of service (QoS) and signal transmission distance, the repeaters be applied to lengthen the transmitting distance of VHF and expand the coverage of radio stations. Under ensuring the QoS, the reduction cost is very important. In this paper, focusing on the different coverage of repeaters, we discuss the minimum number of repeaters to cover a whole circular area, and the square model and cellular model are proposed. Then we analyze the case in view of the simplex communication and duplex communication. Furthermore, the influence of the location of the radio station to the minimum number of repeaters needed is discussed. Finally, we discuss how the minimum number of repeaters changes with the change of the numbers of radio stations. The minimum number of repeaters to cover the circle area will increase as the radius of the repeaters coverage decreases. The radio station in the center of the circle flat can broadcast to the farthest area and the radio station in the fringe area can’t broadcast to farther area. In simplex communication, the minimum number of repeaters with n radio stations in the circle are is n-1 times greater than that with only one radio station.

The forging method with horizontal V – shaped anvil is introduced to control fibrous tissue flow direction through changing shape of anvil, its working face is composed of four projecting cone, it can realize no transverse tensile stress forging. For this, in the paper qualitative physical simulation was carried out. The results show that there was no crack between the hole and the pin in deformation zone of rectangular billet by horizontal V – shaped anvil forging method, therefore, the authors think that there no transverse tensile stress in deformation zone of billet in the forging process of horizontal V – shaped anvil.

In order to make sure the application direction of vanadium extraction tailings, basic characteristics, slagging mechanism of vanadium extraction tailings as well as thermal decomposition temperature and absorbed heat of CaSO4 in vanadium extraction tailings are analyzed, in addition, the effect of charging vanadium extraction tailings under supersaturation state on the sulfur content in steel is studied by using induction furnace under low sulfur condition. The results of research and application indicate that vanadium extraction tailings after desulfuration treatment can be used to steelmaking-slagging, and the application effect is obviously.

Sensorless induction motor drives are widely used in industry for their reliability and flexibility. It’s very important to improve the performance of speed estimation in some cases, especial at low speed of IM drives. The authors have proposed and developed a model reference adaptive system (MRAS) based on discrete time sliding mode algorithm(DTSM), which has high performance for sensorless induction motor drive in low speeds. The new algorithm obtains the identification flux using the classic MRAS, and the PI adaptive law in MRAS is replaced with the sliding mode observer which is acquired by the error function. This paper presents the theory, modelling, simulation and experimental results of the proposed DTSM-MRAS based sensorless direct torque control induction motor drives.

The thermal infrared (TIR) radiation in the deformation and progressive failure of coal roadway and the mechanism of thermo-mechanical coupling were investigated. The experimental achievements showed that the surface TIR temperature (TIRT) rose non-uniformly with the load increase before the stress peak and TIR radiation caused by stress concentration and fracture belt, was much stronger and higher than that caused by stress relaxation, week friction and tensile fracturing. The progressive failure zones were determined from the change ratios of TIR temperature of the different areas of the surrounding rocks. The infrared thermal image anomaly appeared with the macro-cracks development in the progressive failure of roadways, which reflected the spatial and temporal features of infrared precursor respectively. The infrared thermal image precursors were classified as TIRT increment region and TIRT constant region to disclosure the damage evolution and localization behaviors of roadways.

Development of low-sulfur and Pb-free hypoeutectoid graphitized free cutting steel is significant because the use of S or Pb free-cutting steel can result in serious pollution. Due to graphitization process in hypoeutectoid steel is very slowly, so it is crucial to accelerate the graphitization process. The tested steel is prepared based on that graphitization can be accelerated by increasing nuclei of graphite. On the base of indirect observation on graphite particles in the sample by OM and quantitative metallography for different graphitization times, the kinetic curve was drawn the graphitization process of tested sample, it matches the Avrami eqution well.

Extraction method by which auricularia auricula was treated affects the phytochemical composition and properties of the fibre-rich powders. Factor such as the solvent used was studied, and the significance of such changes was largely dependent on the alkali liquor. Among the auricularia auricula phytochemicals, crude protein, glucosamine, fat and carbohydrate were quantified. Crude protein ranged from 9.98% to 4.40%, and fat ranged from 2.51% to 3.71%, and carbohydrate ranged from 88.21% to91.66%, the content being affected by the solvent, in some cases. Dietary fibre (DF) from alkali liquor treatments had significantly higher amounts of glucosamine than samples extracted by water. The water-holding capacity (WHC), water retention capacity (WRC) and oil-binding capacity (OBC) of fibres from alkali liquor treatments were decreased by 51.4, 48.1, and-3.8%, respectively. The cation exchange capacities (CEC) was significantly lower from alkali liquor treatments, and CEC was only 0.02 meq/g fibres that decreased by 95.4%. The results showed that, in order to preserve the DF quality, the extraction solvent should be important. DF functional properties might be degraded or modified.

Based on the submarine soft rock supporting engineering in Beizao Mine, the physical model tests of four kinds of supports were carried out including high strength (HS) roadway without support, HS soft rock roadway with U-shape steel support (U-S-S-S), low strength (LS) roadway with bolt support (B-S), and LS roadway with U-S-S. The thermal infrared (TIR) changes with the fracture and damage of roadway are investigated. It is discovered that the TIR radiation is the stronger in the stress concentrated area, strong friction and interaction range between U-steel support and roadway than that in the stress relaxed area and week friction. The TIR temperature (TIRT) of the fracture increased higher and changed rapidly than other parts. The TIR radiation of soft rock is influenced with seawater. The TIR-anomaly appears at the stress concentrated area, interaction ranges and fractures. The TIR omens occur when load is 65%~90% of the peak load.

With the full consideration of the heterogeneity, existing joints, and cracks in the rock, the coupled gas-rock model for investigating the failure process of coal-rock is established by introducing the related equations governing the evolution of stress, damage and gas permeability along with the deformation of coal and rock. A numerical approach of realistic failure process analysis (RFPA) to simulate the stratum movement, layer separation, the whole collapse progresses, and gas permeability changing of the protected coal seam is proposed. The numerical simulation results well displayed the whole processes of the cracks growth of gas seepage passage and the change of gas permeability for the closed distance protected coal seam. It can be seen from the distribution of acoustic emission in the space that the stratum failure is transferred from deeper to surface. By the analysis of the stress fields changing, the reasons of the gas permeability improvement of the protected coal seam are presented.

A new algorithm, named feature-based visibility analysis is proposed. This algorithm can be used widely in manufacture and process of parts or models. Compared with conventional triangle facet algorithm, the proposed feature-based algorithm can get global visibility more efficiency and accurately. The main visibility analysis consists of two steps: 1) Local visibility analysis. All features are classified into two types-features with local visibility and without local visibility. 2) Global visibility analysis. All features with local visibility should be analyzed further to detect whether the local visibility feature is sheltered by the other part of the model. In this paper, related principle and implement process (on UG flat) are introduced detailly. At last, the case study demonstrated the validity of the proposed method.

For the theory and feature of EDM notching, the actual situation thermal model was established; by finite element method, EDM notch process base on killing and activating elements was successfully simulated, thermal and stress after notching was analyzed, while the conditions and mechanism of cracks generation was discussed.