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For responding the national demand of energy conservation and emission reduction (ECER) and promoting the green purchase of power equipments, it’s highly of importance to perform the analytic process of environmental impacts and total cost in lifetime for power equipments. Life cycle assessment (LCA) is an analytic approach which completely supervises the concerned objective within its life cycle. In this paper the life cycle is hypothetically divided into three main phases, respectively, the production phase, the operation phase and the recycling phase. On the basis of LCA, this study develops a model regarding the environmental impact analysis and total cost calculation for power cable within its life cycle. This model computes the emission level of main pollutants at each stage and illustrates the trend of total cost change with respect to changeable power load parameters. The experimental research indicates that the developed model is practically useful and rational with conclusions. In terms of environmental impacts of power cable, the effect from the production phase mostly lies in the discharge of abundant waste water. And the effect from the operation phase mainly concentrates upon the energy consumption and the emission of greenhouse gas. However, the effect from the recycling phase is very slight. Meanwhile, as for the perspective of total cost of power cable, the operating cost increases obviously as the power load arises.

Step-chirped gratings is utilized to broaden the bandwidth of wavelength conversion based on single-pass/ double-pass cascaded second harmonic generation and difference frequency generation. By adding the step-chirped gratings number and optimizing the poling period, broad conversion bandwidth and flat response can be obtained simultaneously. The bandwidth of 4-cm-long waveguide with 6-section chirped gratings are 169 nm for single-pass scheme and 164 nm for the double-pass one, which are 98 nm and 101 nm larger than those of uniform gratings, respectively. Furthermore, comparison between step-chirped gratings and equal-segmented gratings is carried out.

To study the failure process of metal structure with meso-defects, RVE (representative volume element) with various initial meso-defects were analyzed by using ABAQUS software, the parameter f (void volume fraction) of GTN damage model was regarded as the criterion of structural damage. The result shows that f increased more obvious with volume of defects for spherical defects with the same shape but different size. When the radius of defects is less than 0.15mm, the influence of defects’ volume on increases of f is clear enough. When the radius is greater than 0.15mm, the effects is diminishing. For ellipsoidal defects with the same volume but different aspect ratio, when the long axis perpendicular to the direction of load, the increased trend of f according to plastic deformation more obvious along with aspect ratio of defects. Apparently, as aspect ratio approaches infinity, f would have the fastest growth. Consequently, the bigger defect volume and aspect ratio, the more conducive for damage evolution of the metal structure.

A bacterium capable of simultaneous heterotrophic nitrification and aerobic denitrification at high concentrations of ammonia-nitrogen was screened and identified and the denitrification property was investigated in this paper. The strain was isolated from aeration tank of wastewater disposed by activated sludge and analyzed and identified by 16S rDNA. The effects of different carbon sources and carbon and nitrogen mass ratios on denitrification rate were studied. The changes of various forms of ammonia-nitrogens during the simultaneous heterotrophic nitrification and aerobic denitrification process were characterized. A strain capable of simultaneous heterotrophic nitrification and aerobic denitrification at 600 mg/L nitrogen concentration has been isolated and screened. Comparison of its 16S rDNA sequence showed 100% similarity to Bacillus licheniformis strain Lr124/6. The strain was named as Bacillus sp. A22. The optimal conditions for degradation of ammonia-nitrogen by Bacillus sp. A22 were trisodium citrate as carbon source and carbon and nitrogen mass ratios of 10. The denitrification rate was 98.2% after 96 h of culture under the optimal conditions and there was hardly any intermediates accumulation in the denitrification process. It has practical applications that the denitrification can be performed efficiently at high concentrations of ammonia-nitrogen by method of simultaneous heterotrophic nitrification and aerobic denitrification by Bacillus sp. A22 in nitrogen purification treatment of wastewater with high concentrations of ammonia-nitrogen.

The paper is devoted to a theoretical study of nonlinear wave on a free-surface thin film down an inclined uneven plane. The problem is quite different from that of a viscous films flow along a smooth surface. Thus nondimensional variables are introduced in two ways according to the different relationship of the shallow water parameter and the topography parameter. Further, the zero-order and first-order stream function are derivated on the basis of perturbation method. Finally, the equations which govern the surface height of surface wave on a viscous fluid film down an inclined uneven wall are obtained.

Peer review is a new phenomenon in the process of internationalization of academic journals, but also a worldwide problem. In this paper, the development and practical application of peer review system are sort out, which are based on objective data research of domestic and international academic journals; the problems of network online published papers in practice are analyzed and explored by modern advanced network technology as the application tool, and how scientific orientation are they to play an effective role. The purpose of paper is in order to ensure the impartiality of the academic council, spread rapidly and use information resources, and further promote to enhance the overall level of academic journals.

In order to enhance the signal intensity of VLC-LED receiver, this paper describes a receiver condenser which is designed based on optimized CPC (compound parabolic concentrator) by using a truncated method, for achieving the aim of boosting receiver’s ability of gathering light and enhancing signal intensity. The Monte Carlo-ray tracing simulation results shows that in the VLC-LED system, the optimized CPC condenser has those advantages, such as higher concentration ratio, larger concentrate light deviation angle.

The adjustable high-power distributed DC power supply controlled by DSP presented in this article is a new type of electronic power supply. Considering the features of modern power system, this article discusses and compares the principles of technical design and application of the adjustable high-power distributed DC power supply controlled by DSP with those of traditional DC power supply. The result suggests that the adjustable high-power distributed DC power supply controlled by DSP is easy to install, energy-saving and environment-friendly. It also has the characteristics of lower cost and higher performance.

In the context of south china electricity market, the concept of contract transfer and replacement deal is set forth in advance which is specialized in electricity treatment. Then, the feasibility of conducting an inter-provincial contract transfer and replacement is analyzed according to the aspects of physical characteristics, economics and policies within the china southern power grid. In addition, the advantage and disadvantage are also presented in terms of bilateral negotiation and centralized biding transaction modes. After that, the pricing mechanism and transaction mode are deliberately designed pertaining to three different situations including a party power shortage and a party "abandon water", a party power supply shortage and a party power surplus and a party power surplus and a party "abandon water". Finally, the realistic feasibility of the proposed schemes is verified through an employed numerical example.

A survey for water heater in urban residential buildings is carried in Wuhan. The results show that more than 40% subjects use solar energy water heat. More than 20% subjects point out the energy consumption of water heater should be decreased. There are about 24.8% subjects take initial cost as the first place when they chose water heater. 44.2% subjects know about heat pump water heater, but they could not buy it if the initial cost is too high. There are 84% subjects could select heat pump water heater when the cost is no more 20% high than the average price of the common water heaters. Moreover, the energy consumptions of residential water heaters are also investigated. The energy consumption characteristics of water heater in Wuhan are analyzed.

FBG concentration chenical sensor with three layer structure is proposed in this paper. And through experimental study and reasoning calculation to verify the three layer structure of the optical waveguide model, so the sensitivity characteristic of the Bragg wavelength to the refractive index of chemical solution is obtained. And the relationships between the concentration and the shift of Bragg wavelength of sucrose, ethanol, and Nacl solution are achieved. Finally the shifts of the Bragg wavelength with the external concentration are obtained by experiments.

The main building of the Hubei press has a horizontal contacting passageway in the middle of two buildings in the fifteenth floor, which has attractive appearance and like a doctorial hat from afar. The structure is reasonable and more stable with the diagonal bracing and the beam. Analysis and research in this paper can provide reference for the design of this structure.

A new Low interference inductor is presented for wireless transmission in 3D Package. An accurate physics-based method is employed to calculate DC inductance of the new shape on-chip inductors. All inductor size parameters are considered in the method including metal thickness and inter-layer space. Due to its physics-based nature, the proposed method is scalable. The results calculated by the proposed modeling show the new inductor is of lower interference than the common one. The new inductor can transfer more efficiently than the common one.

Design an intelligent concentrator of heat meter reading system for residence and illustrate the principle of M-BUS communication. Develop the communication protocol of M-BUS between heat meter and intelligent concentrator. ARM9 processor is adopted to be the core of the hardware construction, the software of the concentrator adopted embedded Linux, modular hardware drivers and functional design are placed in this device. Develop the data receive circuit and data send circuit of M-BUS of concentrator and application program. M-BUS communication protocol is used to implement the data transmission between the concentrator and the heat meters. This device has the features of security data transmission, convenient reading and strong real-time.

In LTE-Advanced (LTE-A) system, coordinated multi-point (CoMP) technology can reduce inter-cell interference effectively, and improve the communication quality of the cell edge users. The main purpose of this paper is to optimize the precoding algorithm and enhance the overall cell throughput in LTE-A CoMP downlink. Based on CoMP-JP, we focus on zero-forcing (ZF), block diagonalization (BD) and signal-to-leakage-plus-noise-ratio (SLNR). We propose an improved precoding algorithm (ZF-SLNR) which combines the advantages of ZF and SLNR . Simulation results suggest that ZF-SLNR algorithm provides appreciable performance improvement.

ETC has become an urgent need of social development. This paper first analyzed the current situation of highway ETC, then researched on RFID technology, established the city ETC system based on RFID, it greatly improves city vehicle management efficiency, prevents manual vulnerabilities, promotes the city automation construction.

With the gradually maturing super-speed inkjet printing technology, people are pursuing steadier and higher speed as well as better quality presswork for the sake of increasing economic benefit. To provide an overview of the velocity fluctuation of the inkjet machine platform and the cyclical fluctuation of the incremental encoder, external clock and corresponding internal clock were applied separately to print the equally spaced lines under the same platform speed. Then a magnifier was used to measure distance between the lines, according to which the velocity fluctuation mentioned above can be obtained. Thus conclusion can be drawn from the fluctuation analysis that the velocity cycle of platform is 60mm, however, number of those produced by the incremental encoder is up to 3, including 60mm influenced by the platform, 300mm produced by the perimeter of encoders pressure wheel and 600mm produced by the circumference of dance roller. Furthermore, dance roller contributes more influence on narrow coated paper. Through this research, inkjet technician can do directional compensation for every factors to reduce the fluctuation.

A mathematic model of ball screw was constructed which was based on the elastic contact deformation theory. The helix angle was considered and the formula of axial elastic deformation was deduced in this study. Furthermore, a finite element model of ball screw was established and its elastic deformation results were also acquired. And the effect of contact angle on axial elastic deformation was analyzed by theoretic method and FEA. The study shows that the axial elastic deformation of ball screw changes with the contact angle. The deformation will decrease by the contact angle increasing, and the positional accuracy of the ball screw is improved.

As one of the crucial issues of computer vision, video object tracking is widely used in many applications, such as visual surveillance, human-computer interaction, visual transportation, visual navigation of robots, military guidance, etc. The existing object tracking algorithms in engineering applications have the huge amount of computation, which can not meet the needs of real-time system applications, and the tracking accuracy is not high. So a simple and practical video object tracking algorithm is proposed in this paper. The Otsu algorithm is used for image binarization to filter the background, and the object edge is further processed based on mathematical morphology, and thus the tracking object is more clearly. The centroid weighted method determines the location of the center of the object only by one step calculation, which makes the location more accurate. The experimental results show that the algorithm of the paper is effective for detecting and tracking of a moving object in a static scene and it has a low complexity.

To improve the contrast ratio and brightness of video surveillance image in mine, we modify the histogram equalization algorithm by extent the boundary when calculating the sum of gray probability. Experimental results show that the algorithm can reserve the characteristics of the histogram equalization and improve the image’s brightness.

Mechanical properties of the calcium-plastic composite have a great influence on the containers. The main factors affecting the mechanical properties are the process and material formulations. This paper mainly describes its impact of the addition of coupling agent. Under the usage of analysis of variance on single factor experiment, the mechanical properties of the calcium carbonate-plastic composite with three different coupling agents (silane, titanate and aluminate) were studied in the same test conditions. The results show that: The type and quantity of the coupling agent effect a lot on the mechanical properties of the composite. The silane coupling agent is the most suitable for calcium carbonate-plastic composite packaging materials, and the compatibility of calcium carbonate and polyethylene can be improved. When the silane coupling agent was at a 2.25 wt. % concentration, the tensile and flexural strength were improved obviously, especially the tensile strength increased by 23.24%, but the impact strength improved slightly.

The basic parameters of calcium carbonate-plastic composite packaging materials, such as tensile strength and flexural strength, were obtained by means of mechanical properties test at different temperatures. Through the experimental tests, the best processing temperature was determined at 190°C and the test data were fitted and optimized. Also, the residual of fitting curves was calculated by using the mathematical analysis software of MATLAB. Besides, mathematical models were established between temperatures and target parameters, from which the mechanical properties of materials at any other temperatures can be predicted theoretically. So, it provides a scientific basis for the regulation of processing temperatures.

When the parameters were measured by using fiber Bragg grating (FBG) in practice, there were some parameters hard to measure, which would influenced the reflective spectral of FBG severely, and make the characteristic information harder to be extracted. Therefore, particle swarm optimization algorithm was proposed in analyzing the uniform force reflective spectral of FBG. Based on the uniform force sense theory of FBG and particle swarm optimization algorithm, the objective function were established, meanwhile the experiment and simulation were constructed. And the characteristic information in reflective spectrum of FBG was extracted. By using particle swarm optimization algorithm, experimental data showed that particle swarm optimization algorithm used in extracting the characteristic information not only was efficaciously and easily, but also had some advantages, such as high accuracy, stability and fast convergence rate. And it was useful in high precision measurement of FBG sensor.

Series of biaxial compression simulations are carried out to investigate the effects of boundary condition on the deformation of granular materials by using DEM. The parameters used in DEM are validated by the biaxial compression experiments on elliptical steel bars. The effects of boundary condition on the stress-strain relationship are analyzed. And special focus are put in the analysis of particle displacement, particle rotation, void distribution, particle long axis orientation and contact force with the development of deformation.

The data for establishing digital basin has the features of large quantity, heterogeneity and multiple dimensions. Determining how to effectively manage and share the data is the key for digital basin. This paper shows an information sharing model for digital basin based on metadata directory, Service-Oriented Architecture (SOA) and publishing/subscription technology. And then, for easily transmission, we preliminarily accomplish the data conversion based on Geography Markup Language (GML).

This paper presents a new vibration isolation module which is set somewhere out of pier footings of footbridges. The isolation vibration effect of the vibration isolation module was analysed by means of experiment and FEM analysis. The attenuation decibels of the vibration strength were measured and researched under various working conditions. Making use of the finite element program, the new vibration isolation module was simulated and calculated. That the calculated results were in good agreement with the measured ones indicated the reliability of the numerical model. The simulation and measured results suggest that vibration reduction effects are satisfactory. The results can provide reference for vibration attenuation and vibration isolation of footbridges.

The simulation analysis of the cantilever construction process was carried out with the structure analysis software. This paper provides an overview of the geometric control and the overall computation according to actual criterion, taking into account the effect of temperature, concrete shrinkage and creep, pre-stressed tension and so on. The elevation monitoring was carried out by comparing the calculated values with testing data. The analysis and control of the line shape are good to perfect the construction control technology of the closure section, enhance the closure quality and ensure the smooth of entire line shape and the rationality of the main beam internal force.

Railway plays an important role in transportation system in China or many other countries. In order to solve the problem of cleaning sand-covered railway in western areas of China emergently, a new railway sand removal vehicle is studying, and as the most important mechanism, the sand scraping mechanism affects entire efficiency and even determines the success or not of the whole vehicle, therefore, structures of the mechanism were designed and further studied by using UG and ANSYS software.

Characteristic information of FBG reflection spectra changes because of the existence of demodulation system error in the actual demodulation. The analysis of spectra for FBG under axial uniform force based on particle swarm optimization is given in this paper. Objective function is established and force experiments and numerical simulation of fiber Bragg grating have been made. The characteristic information of FBG reflection spectra under axial uniform force is extracted and theoretically reconstructed. The results show that, the improved particle swarm algorithm in fiber grating reflection spectra analysis is feasible. Also, the method has other characteristics such as high accuracy, good stability and fast convergence speed.

Iron ore tailings as a kind of waste products after ore dressing is one of the major industrial solid wastes. Iron ore tailings not only cover huge land and pollute environment, but also give rise to security risks. The comprehensive utilization of iron ore tailings need to be studied systematically. According to the method in Test Methods of Materials Stabilized with Inorganic Binders for Highway Engineering, the technical performances of cement stabilized iron ore tailing gravel in highway application were studied by systemic experiments in this paper. These include the strength, modulus, and frost resistance property, water stability. And the influencing factors of the mixture strength were analyzed, too. The results show that the mixture of cement stabilized iron ore tailing gravel has higher strength and modulus, good frost resistance property and water stability. The technical performances of cement stabilized iron tailing gravel conform to the current specification, so it can be used as sub-base course or base course material.

In this paper, the feasibility of river sludge subgrade with construction waste is studied through CBR test and limit moisture content test. The variation that the carrying capacity of river silt with the increase of mixed proportion of construction waste is analysed, and the suitable mixing ratio is obtained that to filling roadbed with river sludge and construction waste.

A new conception, called the Most Direct Impact Area (MDIA) of typhoons, is put forward in this paper. After the computational method is explained in detail, the databank of 1955 typhoons of China Meteorological Administration (CMA) have been calculated on the Linux operational platform with a Fortran compiler in a computer. The results via calculating the geographic distribution of the MDIA of typhoons show that the characteristic of typhoon activity in a year can be easily identified in quantity. A most interesting feature has been found that typhoon activity is abnormally active over the ocean to the south of Japan in three typical El Niño years.