Search

The effects of oxidized copper ores which came from Yunnan province were carried out by using ammonialeaching methods in the laboratory.In order to seek the optimum leaching conditions under normal temperature and pressure,we conducted a series of validation experiments. Theoptimum conditions were obtained as follows: ammonia concentration 2.5mol/L, ammonium sulfateconcentration 2.5mol/L,grinding fineness about 80% -0.074mm, liquid-solid ratio 2.5:1and leaching time was 2.5h. Under these experimental conditions, the copper leaching rate could reach 69.91%.

For the comprehensive recovery of copper, zinc, silver and iron from the zinc volatile kiln slag in Xining, exploratory experiments were conducted by adopting single flotation, magnetic separation and combined process of magnetic separation and flotation. The results showed that the above process cannot effectively recover copper, zinc and silver from the ore. The recovery of iron is better by single magnetic separation. The grade of iron concentrate reaches 69.05% and the recovery is 41.86%.

In order to solve the problem of data collision in the electronic countermeasures simulation scenario edition, a scenario data collision detecting algorithm based on productive inferring, whats more, a scenario data collision detection system for electronic countermeasures simulation is designed and actualized. This system can be integrated into electronic countermeasures simulation system regarded as a component, to check the scenario data and ensure the datas rationality.

Based on the requirement of small errors in measuring roundness (cylindricity) error, a leveling methodology which using a dual-point vertical layout has been put forward and analyzed. According to the direction cosine of the axis of workpiece, the amount of leveling has been defined and calculated, which overcomes the problem brought by manual adjustment technology and forms theoretical bases of fast, accurate leveling and high precise measurement. The assessment of roundness (cylindricity) error is to search for a center (cylinder axis) which satisfies the minimum condition. Due to the reliance of initial solutions and relative slowness in terms of convergence precision and convergence rate when using Nelder-Mead simplex method, a combinative method of Quasi-Newton and N-M simplex method has been proposed which achieves a fast, accurate search for global optimums. With the proof of the simulation of classical testing functions using Matlab and the measured data, the convergence rate and precision will be enhanced effectively has been certified with the combination of both methods mentioned above which ensuring and improving the measuring precision of workpiece.

A robust adaptive fuzzy control scheme combined with an adaptive fuzzy control algorithm and H∞ control model is proposed for the trajectory tracking control of robot manipulator with structured and unstructured uncertainties. The adaptive fuzzy control algorithm is employed to approximate structured uncertainties, and the nonlinear robust H control model is designed to eliminate the effect of the unstructured uncertainties and approximation errors. The validity of the robust adaptive fuzzy control scheme is demonstrated by numerical simulations of a two-link rotary robot manipulator.

Agile manufacture execution system is the centre of whole system. The structure and function of the execution system are analyzed, the characteristics of Agent is also given. The Agent modeling method is used in the system, the function or unit can be transformed into Agent, so the setup structure for execution system of the agile manufacture system is build, and the resources, requirements are all brought into the networks. The systems operation relies on the interaction among the functional Agents.

The design of a LED illumination control system based on ARM, infrared technology and ZigBee is described. With the core of S3C44B0X and the infrared sensor collecting the temperature information, the system uses ZigBee technology to do real time monitoring. Through the experiment, the system can make the safe, real time and effective control. It is meaning for the development of the future LED illumination.)

The principle of restraining the harmonic using the series reactors was introduced and the relationships between circuit condition and the harmonic current were analyzed in this paper.The considered problems in selecting the reactance rate were discussed. On the base of power quality test results at a certain region in China, a selection method of reactance rate of series reactors, rated voltage and capacity of a capacitor were put forward to realize the compensation for reactive power.

The leading phase operation of generator is an effective method to reduce voltage of the key point which is much high in valley load period. This paper reviews the history on leading phase of generator and introduces the current situation on stable monitoring of the generators leading phase capacity. Meanwhile, this paper proposes main restricted conditions of generator leading phase and analyzed in details. At last some experiments are performed for part generating sets with a capacity of 100MW above in one province and obtained the experiment results on voltage regulation through leading phase of synchronous generating sets.

A kind of portable digital storage oscilloscope (DSO) is developed in this paper. It builds trigger, storage, measurement module for embedded system with programmable logic resource of FPGA chip. The external digital circuits of a digital oscilloscope is achieved. And it saves a lot of cost by implanting NIOS II soft-core processor as the control unit of the system in the FPGA. This system has the function of automatic frequency control (AFC) and automatic gain control (AGC), and it can measure the signal conveniently.

Windows network packets capture technology is closely related with Windows network protocol architecture. Paper first introduces the Windows network protocol implementation, then analyze the network packets capture technology in the user mode and kernel mode, moreover discuss the data capture technology at the application layer, including API interception technology, dynamic library replacement technology and database trigger technology, finally, the various network data acquisition technology are analyzed, and what kind of data acquisition technology is used depends on the purpose of data capture and the characteristics of the target information system.

We analyze the road environment of the present urban main road and the motor vehicle traffic conditions firstly, from which we see that crosswalks should be added and some intersections should be signal control optimized. Then using the timing linear control system theory which is suitable for China, the paper optimizes the crosswalk and intersection signal timing. Simulation is conducted with simulation software of VISSIM in the end, obtaining that after arterial road coordination, although a crosswalk is added in optimized arterial road, the total stop delay and the travel time of the mainstream vehicles are effectively reduced. The program satisfies the need for pedestrian crossing, and obtains better green wave band of arterial road.

The shortest path between the start node and end node plays an important role in city’s road traffic network analysis system. The basic ant colony system algorithm which is a novel simulated evolutionary algorithm is studied to solve the shortest path problem. But the basic ant colony system algorithm is easy to run into the local optimum solution for shortest path. In order to solve the problem, the improved ant colony system algorithm is proposed. The improvement methods for selection strategy, local search, and information quantity modification of basic ant colony system are discussed in detail. The experiments are done in Beijing road network in China. The results of experiments show that comparing with the basic ant colony algorithm, the improved algorithm can easily converge at the global optimum for the shortest path.

The dimension synthesis of crank rocker mechanism used in torque exciter was carried out with known angular displacement of rocker swing. Optimization method based on minimum kinetic energy of whole mechanism was adopted under constraint condition of minimum transmission angle and mechanism bar existence condition. Optimization design function was applied in solution and a design method of crank rocker mechanism was developed. The torque exciter has been in operation, achieving scheduled function for dynamic performance test, and all testing data are exact and valid.

Due to increasing water scarcity, reclamation and reuse of the secondary effluent of wastewater treatment plant are widely concerned in many countries. Before reuse, the residual contaminant in the secondary effluent should be further removed to guarantee safe reuse. Coagulation/sedimentation and subsequent chlorine dioxide(ClO2) disinfection was adopted for tertiary treatment of secondary effluent. Selection of coagulant and optimization of tertiary treatment parameters were performed in this study. The results showed that coagulation could remove turbidity and total phosphours(TP) effectively. Polyaluminium chloride(PAC) was the most suitable coagulant. The optimal coagulation condition was as follows: PAC dosage of 10mg/L(measured as Al3+), reaction time of 20 min, settling time of 40 min, in this case, the average removal rate of turbidity, color, UV254, TP and TOC could reach to 58.2%, 22.8%, 18.2%, 60.6% and 22.2%, respectively. ClO2could inactive bacteria andE. colieffectively. ClO2could further remove UV254, color and TOC. In case of ClO2dosage of 5mg/L, the sterilization efficiency could reach 100%, and the removal rate of UV254, color and TOC was higher than 25%, 70% and 25%, respectively. In the optimal condition, the removal efficiency of residual contaminant by the combination process was as follows: UV254of 45.9%, color of 76.5%, TOC of 66.7%, turbidity of 61.9% and TP of 96.3%.