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Latest research clearly demonstrates the excellent capability of the gear power skiving technology. For further improvement of the skiving process and enhancement of the process reliability the fundamental research on the cutting mechanism of cylindrical gear power skiving was conducted. First the kinematic model of power skiving and mathematical equations of cutter were established according to the engagement principle of crossed helical gears. Then, based on the proposed model, we investigated the simulation process, chip deformation mechanism and the cutter top relief angle. The results support the skiving cutter design and process optimization and are an important basis for the implementation of the advanced gear process.

As the co-integration theory is introduced, this research attempts to explore the relationship between economic growth and electric consumption based on co-integration theory in Jilin province. The data we use comes from the economic and electricity data in Jilin Province during 1978 to 2013. The analysis results show that a long-term stable equilibrium relationship between electricity consumption and economic growth in Jilin province is existing. Based on the Granger causality analysis, we find that there is no Granger causality between electricity consumption and economic growth in Jilin Province.

The evolution of the microstructure of a typical nickel-based superalloy GH4169 is investigated by the hot compression tests. The microstructural parameters such as fraction of recrystallization and grain size were analysed quantitatively. The results show that the effects of deforming temperature and strain rate on the dynamic recrystallized grain size are significant. With the deformed temperature increase and the strain rate decrease, the dynamic recrystallized grain size increases.

In this paper, a tube electric furnace is used to process the co-combustion of biomass and crude oil in air atmosphere, the influence of the biomass mass fraction and the temperature on NO and SO2 emissions are analysed. Research shows that with the increasing addition ratio of biomass to crude oil, the amount of NO in per unit heat reduces. This tendency is more apparent at high temperatures. Compared with crude oil, the NO emission of 20% biomass mass fraction at 1100°C is reduced by 25.8% while 19.02% at 700°C. SO2 emission in per unit heat decreases with the increasing biomass mass fraction. This tendency is more apparent at low temperatures. Compared with crude oil The generation of SO2 of 20% biomass mass fraction can reduce 91.5% at 700°C while 36.7% at 1100°C.

Two catalysts (V2O5/AC and V2O5/CNTs) with different loadings, prepared by impregnation method, were used to research the DeNOx activity under N2and CO2atmospheres respecitively at the temperature range from 100°C to 300°C using a fixed bed reactor. Effects of temperature, loading and support on the DeNOx activity were studied. The results show that the NO conversion of the both catalysts increases with the reaction temperature. The loading and support have significant effects on the activities. 9%V2O5/AC and 9%V2O5/CNTs yielded 80% and 66.6% NO conversion at 250°C respectively under N2atmosphere, however, they yielded 78.1% and 75.1% respectively under CO2atmosphere.

Experiments of biomass char combustion in 10%O2/90%CO2, 21%O2/79%CO2, 10%O2/90%N2 and 21%O2/79%N2 atmospheres were performed in the fixed-bed reactor system at the temperature of 800°C-1200°C. The results show that at the same temperature, NO emission is higher in O2/N2 atmosphere than that in O2/CO2 atmosphere. The higher the O2 concentration is, the higher the NO yield is. As the temperature rises, the NO yield rises at first and then decreases at the same O2 concentration and atmosphere.

For hardware Trojan detection process is difficult to effectively extract the exact equivalent logic function of the target chip logic function is proposed based on contradictory truth table equivalent extraction scheme and key Enabling technologies. Designed to target chip waveforms attribute recognition model, through the analysis of multiple properties of the model and proof, the work is given waveform attribute recognition model parameter setting principles.

The removal of persistent organic pollutants (POPs) in soils at initial concentrations ranging from 20.00 to 321.05 mg·kg-1 was investigated under different planting patterns, and enhancement mechanisms were analyzed. Results showed that the dissipation of POPs in soils growing Brassica campestris and Medicago sativa significantly exceeded those vegetating single species. During 70-day experiment, about 75.06% of Pyr and 68.22% of BaP was removed from the soils under mixed cropping; while only 31.8% and 64.03% of Pyr and 27.84% and 51.93 of BaP were removed under single rape and alfalfa cropping, respectively. Of all pathways enforcing POPs removal, plant-microbial interactions is the most predominant. These results suggested a feasibility of the establishment of multi-species phytoremediation for improvement of the remediation efficiencies of POPs, which may decrease accumulations of POPs in crops and thus reduce their risks.

Equipment performance degradation model is a key component in its diagnosis and prognosis models. As to slewing bearing, vibration signals are usually non-stationary and with strong white noise, which makes it very difficult to extract useful information from the signals. Therefore, an Ensemble Empirical Mode Decomposition – Principle Component Analysis (EEMD - PCA) based method was proposed to denoise the vibration signals and performance degradation model was established by PCA. To verify the proposed method, an experiment was conducted and the life cycle vibration signals were acquired. After denoising, performance degradation model was established to explain the denoising performance. Results show that the proposed method acquired a better denoising performance than EEMD-MSPCA, which provides a potential for further research.

This paper analyzes a fractured lightning rod on a tower structure at a 500kV substation. By examining the residues of the rods, and utilizing simulation test and finite element analysis, the causes for this incident are discussed in detail, and a technical rationale is provided for preventative measures of incidents of this type.

All-year thermal dynamic load simulating and energy consumption analysis for new energy-saving building is very important in building environment. According to thermal instantaneous response factors method, the paper develop a software to calculate air conditioning cooling load temperature and the dynamic thermal basic data that involve thermal response factors, periodic response factors, Z transfer function coefficient for new energy ­saving walls in building, which will provide the referable scientific foundation for all-year new thermal dynamic load simulation, energy consumption analysis, building environment systems control, carrying through farther research on thermal particularity and general particularity evaluation for new energy ­saving walls building. based on which, we will not only expediently design system of building energy, but also analyze building energy consumption and carry through scientific energy management. The study will provide the referable scientific foundation for carrying through farther research on thermal particularity and general particularity evaluation for new energy saving walls building.

The uniaxial compressive failure process CT images of gray rock were analysised based on Matlab. Matlab is used to transfer gray rock CT images into gray histogram which can be observed directly so as to see clearly the damage evolution process of gray rock under loading. By comparison, gray histogram is consistent with the result presented by original CT image. The gray histogram equalized by Matlab can show clearly the change trend and process of gray rock internal defects and micro cracks. Gray histogram is a good method to observe and analyses CT images.

In the condition of the same span, to change the continuous curved bridge's curvature radius and under the dead load and moving load to compare how the internal force changes in different curvature radius. The finite element model is established to simulate the actual structure by Midas Civil. Results in a continuous curved bridge which main span of less than 60m, under the dead load, bending moment (-y) is unlikely to change, reinforced by a straight bridge can meet the requirements; under the moving loads, the curvature radius of the bending moment (-y) has little influence, should focus on increase in torque and bending moment (-z).

Taking a bridge of 160m long variable cross-section prestressed continuous curved box-girder as the research object and analyzing the cross-sectional design of axis with axial symmetrical or axial non-symmetrical to research the structure forces change of the upper part of bridge in different curvature. In order to test and verify the variable cross-section of prestressed continuous curved box-girder bridge is safe and reliable via cross-sectional design with axial symmetrical instead of axial non-symtrical within a radius of curvature of the interval. Creating the straight bridge and curved bridge models with different radius of curvature in same span by Midas/Civil to compare their structure forces.

Detecting the location offset of laser spot center method to monitor roadbed settlement is a kind of portable, easy to layout method. Detection laser spot center offset, we can use gravity, circle fitting, ellipse fitting and Gaussian curve fitting, etc method. Gravity algorithm is only involves basic arithmetic and low precise, and ellipse fitting is higher precise. Because of the angle between the optical axis and the target, the laser spot is more approximate as a ellipse. Using the ellipse fitting algorithm, Sub-pixel precise threshold segmentation and Canny edge extraction we obtained an ideal monitoring precise of the roadbed settlement.

Through the analysis of application status of internet of things technology and cloud computing such as the new generation of information technologies in the wisdom agriculture and the existing problems, we puts forward the integrated model of IOT, cloud computing and agricultural information technology, and agricultural technology system architecture model of new generation information technology conditions.

There are many defects in the traditional manufacturing and marketing mode of steel business such as poor connection and planning between manufacturing and marketing and imperfect quality management system. Based on an information system reformation project in a Iron and Steel Group Co, Ltd, system framework of manufacturing and marketing integration for iron and steel enterprise and its implementation points are presented and discussed in this paper.

According to the chatter phenomenon of 3rd stand of a steelworks six-roller tandem cold mill (TCM), vertical vibration of tandem cold mill was simplified to eight degrees of asymmetric freedom mass-spring system. Virtual prototype model on vertical vibration of tandem cold mill was established and natural frequencies and main vibration mode of mill were solved by using automatic dynamic analysis of mechanical systems in software ADAMS. The modal coordinates of main vibration mode of the mill were referred firstly and obtained; the maximal mode of vibration system was found and finally discovered the fifth-octave-mode chatter was the probable vibration of the mill.

Combining the site relocation project of New Era Cement Co. Ltd, the early temperature and strain monitoring and numerical simulation are done on the cement vertical mills mass concrete equipment foundation sizing 15.6m×15.6m×5m, thus, the early trends and rules of mass concrete about temperature and strain are analyzed. Prevent temperature cracks due to temperature strain in mass concrete, therefore, ensure the construction quality of mass concrete.

Wind/Photovoltaic hybrid generating system can alleviate power fluctuations caused by the single source and improve the system power supply reliability. In the stage of planning, the grid-connected scheme and capacity limit calculation problem is needed to solve. Under different schemes, the capacity limit is different. This paper established an optimization model of capacity limit of wind/photovoltaic power station, introduced the tracking center trajectory interior point algorithm to solve capacity limit, and demonstrated the validity of the proposed method by a simulation of IEEE 30-node system considering the reserve capacity, and concluded that capacity limit is larger when Wind/Photovoltaic is parallel in heavy load nodes. This method can provide reference for practical system of calculating capacity limit of wind farm or photovoltaic power station and is feasible.

Dibutyl phthalate (DBP) as a commonly used plasticizer can be detected in many environmental medium. In this study oxidative damage effect on testicular germ cells and liver cells in mice induced by DBP were investigated via vitro test. Testicular germ cells and liver cells of mice were incubated with medium containing DBP in different concentrations (0μmol/L,10μmol/ L,50μmol/L,100μmol/L), after one hour thiobarbituric acid assay and xanthine oxidase assay were used to measure the levels of malondialdehyde (MDA) and the activities of superoxide dismutase (SOD) respectively.The results showed that the levels of MDA in testicular germ cells and liver cells increased gradually with the increase of DBP concentrations, while compared with the control group, the activities of SOD declined significantly at dosage of 50μmol/L and 100μmol/L. These results suggested that DBP could cause lipid peroxidation in testicular germ cells and liver cells of mice in vitro. Oxidative damage may be one of its toxic mechanisms. It would provide an experimental foundation for security application of DBP.

The concept of proxy re-encryption (PRE) was first introduced by Blaze et al. Since then several CCA secure PRE schemes have been presented. Weng et al. proposed a non-transitive bidirectional PRE scheme without pairings and proved that their scheme to be PRE-CCA secure in the random oracle model under the CDH assumption. However, we show that Weng et als non-transitive scheme is still transitive under the formal definition of non-transitivity presented in this paper. Moreover, the transitivity of Weng et al.s scheme also implies that it is not PRE-CCA secure.

Thispaper puts forwards a design method base on a electric power-assisted HybridElectric Vehicle (HEV), which take dead-weight into account to design itsparameter of pivotal components among many actual design methods. Then simulatingand analyzing are made in ADVISOR about its fuel economyand emission. The results of simulation indicated that the fuel economy andemission levels of electric power-assisted HEV which take dead-weight intoaccount to choose its powertrain parameters is far better than the vehiclewhich used the conventional method.

With the development of sour gas reservoir, the utilization of horizontal well technology has a great significance. The accurate prediction of the productivity of horizontal well in developing sour gas reservoir will become more and more important. In this paper, productivity prediction formulas of the horizontal well are established with considering the effect of sulfur deposition on permeability. The effects of the length of horizontal well, the effective thickness of the reservoir, elemental sulfur deposition and reservoir heterogeneity on productivity can be analyzed by established formulas. According to the field case, the calculating results of improved Joshi’s equation approaches the real productivity, which means that it could be used to predict the productivity of horizontal well at initial stage during sour gas reservoir development. The results can be used as a reference for the development of similar sour gas reservoir.

Acoustic emission technique is an important technique for monitoring crack propagation and failure process of rock, coal and concrete material. A uniaxial compression test with acoustic emission monitoring on coal and rock samples’ deformation and failure process were carried out. Failure precursor information of rock, coal and concrete material were studied through contrast analysis the experiment result include acoustic emission signals, strain, load correlation of sample inner crack propagation to failure process. The test provided necessary data to further understand on rock burst failure disaster. The test result provides a theoretical basis for further application of acoustic emission for prediction coal rock dynamic disaster, assessment rock and concrete structure stability and study rock concrete material failure process mechanism.

The concrete would crack when the temperature stress caused by hardening concrete hydration heat and shrinkage action were over the concrete’ tensile strength. The concrete were added with different amount of fly ash in order to increase concrete’ tensile strength and ultimate tensile strain capacity or consider economic perspective. The mechanics performance tests were carried on mass concrete with different fly ash bulk volume. The test results showed that the fresh fly ash concrete’ workability, hydration heat, compressive strength and durability were obvious superior compared with ordinary concrete.

In this paper, the Poisson problem with homogeneous Dirichlet boundary conditions on the bounded open domain is considered and the superconvergence property of 3D tensor-product block finite elements is analyzed by using a computer-based test.

Using WSN, embedded and intelligent terminal technology, realize the city lighting state information detection and data communication, data processing, remote monitoring. Based on JN5148 realization of wireless sensor network, NoSQL, Baidu Map and Android to implement the data monitoring. The system can improve the management level of city lighting facilities and the difficulty of operation maintenance, has a certain practicality.