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Based on the basic principles of anti-islanding detection, this paper puts forward an anti-islanding (AI) detection method which combined/q-axis voltage decoupling and positive feedback with Euler-Lagrange (EL) model .The proposed method is classified as an passive islanding detection method and it is based on the voltage change at the point of common coupling (PCC) that occurs in islanding .In the method, Add the d-axis decoupling voltage of PCC to the d-axis reference current of the EL model. A simulation study shows that the method is simple and feasible.

The predominant pyridine alkaloid in modern tobacco (Nicotiana tabacum) is Nicotine. However, with the existence of a class of Nicotine demethylases, a large proportion of Nicotine will be converted into Nornicotine during leaf senescence. Identification of Nicotine demethylases in modern tobacco is important, since Nornicotine will be nitrosated into N'-nitrosonornicotine (NNN), which exhibit carcinogenic properties in laboratory animals and is harmful for human heath. Although many efforts have been performed to identified, no comprehensive analysis was carried out for the subfamily of Nicotine demethylases. In this work, we performed a phylogenetic and comparative analysis for Nicotine demethylases with their highly homologs. A single and conserved mutation of W->C will prohibit the activity of Nicotine demethylases. Thus, the proportion of Nornicotine could be dramatically decreased if all Nicotine demethylase were single mutated by transgenic manipulation. Our results provide an insightful and solid foundation for further experimental design.

To avoid local convergence and slow convergence of GA, SVM was used to get the fitness function in this paper and Statistical Learning Theory was used to guide the optimization process. Then, the improved GA was applied to Optimizing Cigarette Logistic Distribution Routing Problem, and the result proved that the algorithm was efficient in convergence.

It concerns about escaped dust issues of Inner Mongolia Datang International Xilinhaote Mining CO, LTD.M102. M103. M106 among three belt drive. It will reform and design for dust comprehensive pollution control in belt drive, introduce practical application of High-pressure micro fog dedusting system in belt drive and capture dust particulate effectively in order to make dust fall in the beginning of producing dust by investigation on the site, current specific situation, local climate and water resource.

It concerns about issues of dust pollution of three feeder which in the underground passage under the storage warehouse of Inner Mongolia Datang International Xilinhaotes Mining Company Limited.By inspections and investigations in the field,according to site-specific circumstances and local climatic conditions,we had implemented comprehensive renovation project of coal dust of feeder in underground passage,and achieved remarkable and effective governance results.

There is serious inter-symbol interference (ISI) when ultra-wideband (UWB) wireless communication systems work at high data speed since there is much larger channel delay spread. The serious ISI becomes a major factor that affects the performance of UWB systems. In this paper, suppression ISI is developed for direct sequence spread-code division multiple access (DS-CDMA) UWB systems with a high data speed, and a joint chip equalization adaptive Rake (JCE-Rake) receiver is proposed. The proposed JCE-Rake receiver spreads the number of traditional Rake receiver taps to collect multi-path component and equalize the inter-chip interference simultaneously. Then the soft output of JCE-Rake receiver is despreaded with the user's spreading code. Finally the decision is made to recover the transmitted symbol. The simulation results verify that ISI is suppressed effectively and the system performance is improved evidently.

In recent years more attention is paid to high-efficiency and nontoxic corrosion inhibitor. Synergistic inhibition is an effective means to improve the inhibitive force of inhibitor. The aim of this work is to attempt to find out inhibition mechanism and synergistic effect of Lysozyme (LYZ) and vitamin B1 (VB1) and to diversify the application of inhibitor in acidic medium. The corrosion inhibition effect of LYZ and VB1 for carbon steel specimens in 0.5 mol•L-1 sulphuric acid solution have been investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) methods. The obtained results show that carbon steel is more efficiently protected by the mixture of lysozyme and vitamin B1 (LYZ-VB1) than LYZ or VB1. By potentiodynamic polarization method, the highest inhibition efficiencies of 89.5% and 80.04% are observed with single LYZ or VB1, respectively, and an improved inhibition efficiency of 94.2% is obtained with LYZ-VB1 at 25°C.

For the disadvantage of the induction motor direct torque control system’s performance when it runs in a low velocity, the full order flux observer is used to achieve the stator flux observation, and the flux observer precision and the convergence rate depend on proper allocation of the observer poles. Based on the analysis of two full order flux observer pole placement methods,a single degree of freedom pole placement method is proposed, analyzed and discussed. This method can assign the configuration parameters of the observer gain matrix effectively. The simulation results show that the new pole assignment method can effectively inhibit the motor parameter variations and motor rotational velocity impacts the observer gain matrix’s parameters, so it can improve the flux observer and the observed convergence rate precision.

Based on diesel engine, the digital collaborative platform was designed. The key technology of supporting the platform was introduced. In addition, the principle of digital collaborative design was designed. For a diesel engine, the flow of design was introduced. In every step, the designed contents were determined. Compared the traditional design, the new design will have the shorter period and the better design quality.

Temperature plot is crucially important for numerical simulation of high waxy crude pipeline because of its non-Newtonian behavior at low temperature. As the fluid temperature drops below than the wax appearance temperature, the viscosity of the crude increases dramatically. Thus the needed pressure has a possibility to reach the maximum allowable pressure and cause a potential risk for the pipeline itself. To avoid this, numerical simulation of the temperature plot along the pipeline is necessary in order to obtain accurate information. However, as the temperature governing equation is a non-linear equation and the soil temperature field is also being involved. It is required to solve the surrounded soil temperature field. In the paper, the governing equation for one dimensional crude pipeline and the new moisture-heat equation for the soil (porous medium) are presented and the iteration algorithm to solve this coupled equation is given. With the algorithm and the coupled heat-moisture equations, the numerical results are obtained and have a very precise coincidence with the experimental results. Then a reliability based method is used to evaluate the flow safety of one pipeline in China. With the presented model and obtained results, the flow safety evaluation results show that the safety of the crude pipeline is assured in the test cases.

The aim of this paper is mainly to study the main coal-dust pollution sources in the coal preparation plants of Ping Shuo Branch of China National Coal Group. Through the combination of many measurement data with numerical simulation of gas-solid two-phase flow, dust precipitation mechanisms have been gained for the feeder in Ping Shuo Coal Preparation Plant. Dust pollution of the feeder is caused by the positive pressure of the induced feeding wind-flow and the bad seal itself. Firstly, the durable flexible seal material is used to seal up the feeder. Secondly, the seal guide-chute with the dust collector is installed on the belt. Finally, the air volume and the pressure of the dust collector are determined by means of numerical simulation, and the reasonability of the plan is explained from the angle of the dust control mechanism. The main technical parameters of the dust control plan, such as the seal guide-chute length, and the air volume and the pressure of the dust collector, are determined through the numerical simulation. The simulation result and the actual result verify the above dust control plans. The study methods and results provide a guide for the dust control in a certain similar business.

In view of the spiral bevel gear machined by the semi-generating means, a new method to create 3D solid model is proposed. The equation of tooth profile surface is deduced from the principles of spiral bevel gear engagement and cutting, according to the position relationship of the machine tool, the cutting tool and the workpiece, along with the cutting tooth process. Then the three-dimensional solid model of spiral bevel gear is developed with the delphi program using the known parameters and the above mathematic equations. The effectiveness of this method has been demonstrated.