Advanced Materials Research Vols. 433-440

Abstract: A 2D current and water quality model was set up with Delft3D-FLOW in this research, which was well calibrated and verified with the observed tidal levels and velocities. Considered with the project of the Qingcaosha Water Source, Pollution concentration distribution caused by sewage outfalls in the south bank of the Yangtze River during a neap tide of dry season is simulated and the computed results show: a high pollution zone appears near the south shore, and moves upward with flood flow and downward with ebb flow, however, it is bounded a limit region around the outfalls. During the tidal period, the water quality of the Qingcaosha water source can be classified as the second class water, which can ensure the normal water supply as the Shanghai water source. It is suggested that the regular monitoring water quality in this high pollution zone should be put into practice to ensure the water quality of water sourecs. The Yangtze River is adjacent to the East Sea and it’s the largest river in China, with obvious seasonal variant runoff and tidal flow. The Yangtze River was bifurcated by Chongming Island to south and north branch from Xuliujing, most of the flow go down through the south branch. The south branch was divided into south and north channel by Changxing Island and Hengsha Island. The south channel was bifurcated by Jiuduansha Shoal to south and north passage, three bifurcation areas and four estuarine outlets were formed (see Fig 1.)

Abstract: This paper summary the investigation and analysis of thermal energy storage extracted from solar heater and use for domestic purpose. Choosing a suitable phase change materials paraffin wax used for storing thermal energy in insulation tank. The tank carries minimum of 45 liters capacity of water and 50 numbers copper tubes each copper tube carries minimum of 100 grams PCM materials. Inside the tank phase change materials are receiving hot water from solar panel. This solar energy is stored in Copper tubes each copper tube contains PCM Materials as latent heat energy. Latent heat is absorbed and stored in Copper tubes .Large quantity of solar energy can be stored in a day time and same heat can be retrieved for later use. The tank was instrumented to measure inlet and outlet water temperature. The differences of temperature of the water is measured in a definite interval of time have been noted then calculating heat transfer rate and system effectiveness. The heat storage system is to be applied to store solar energy and the stored heat is used for domestic hot water supply system.

Abstract: This work discusses the basic principles of Voltage-Chopping and energy-saving technology for the three-phase AC asynchronous motor running in the low load conditions causing the low power factor and low efficiency. On this basis, Developed chopping control and energy saving controller for three-phase AC asynchronous motor .By real-time detection of power factor and other parameters，the energy-saving controller using PWM chopped-controlled voltage regulator means regulating the motor supply voltage to achieve the purpose of energy saving.

Abstract: This paper studied the impacts of land use/cover change on soil erosion in Fujian mountainous areas on the basis of analysis on long period inspection and experimental materials in Jianou Niu Kenglong Experimental Station and the Provincial Soil and Water Conservation Station, researched soil erosion mechanism of mountain grassland ecosystem, and different soil erosion modulus under different land use and land cover types. Through analysis, we have got the results that the coefficient of runoff has minus linear relation with grassland coverage, and the modulus of soil erosion has index relation with grassland coverage.

Abstract: A scarifier mechanism with rotary tillage and anti-rotary grubbing is proposed for inducing the power of tillage in hardens soil. MAT147 material modal is amended by experimental method and soil high-speed cutting finite element modal is build through SPH method, further, the tools parameter of proposed mechanism and soil cutting speed are studied by FEA numerical simulation through orthogonal experiments method. Finally, the result shows that the proposed mechanism with proper structural parameters and work speeds can reduce the requirement of power of tillage and increase the working efficiency of small agricultural machinery.

Abstract: Mathematical model of the storage tank for air-conditioning condition was established, the dynamics character of a new type of PCM in the storage tank was studied., and the model was numerical simulated by the method of heat capacity. Effects of flow rate and inlet temperature of heat transfer fluid (HTF) on charging process of the storage tank were obtained. The results show that no appreciable change in the total cold thermal energy storage is observed for the increase of flow rate, whereas the improvement of the total cold thermal energy storage due to the decrease of inlet temperature is detectable, when cold storage is finished during low peak of electricity, the best inlet temperature of storage tank is at 2°C-3°C.

Abstract: In order to diagnose mine fan fault timely, to enhance and improve the level of safety of coal mining enterprises, construct fuzzy expert system based on multiple symptom. The system presents a inference model based on rules and cases, establish fault diagnosis knowledge base of the rules and cases.Using pros and cons mixed reasoning strategy, according to the fault symptom obtained from man-machine conversation, dialogue diagnosis was carried out on the equipment fault.Use the calculation of symptom and rules confidence to produce fault result confidence to screen and order the faults,and export supporting information such as the diagnostic process explanation and maintenance plan and so on,which is convenient for users to understand and carry out various processing.

Abstract: In wireless sensor network, there are many hurdles takes place in providing quality of service routing to a desired level. The majority of routing protocols in wireless sensor networks concentrates on energy efficiency as a prime factor. Developing an energy–efficient routing protocol has a significant impact on the overall lifetime and stability of the sensor network. In this paper, we have considered three types of sensor nodes. Some fraction of the sensor nodes are equipped with the additional energy resources than the other nodes. We have assumed that all the sensor nodes are uniformly distributed. In the Heterogeneous WSN, we proposed an energy efficient cluster head election protocol and using the improved Prim’s algorithm to construct an inter-cluster routing. Simulation results show out method is more efficient to reduce and balance energy consumption and hence prolong the lifetime of WSN.

Abstract: Based on wavelet transform and support vector machines, a method of recognition and classification of transient power quality disturbance is presented. Using wavelet transform time-frequency localization characteristics, according to the principle of modulus maxima, realize the automatic detection positioning. After multi-resolution signal decomposition of PQ disturbances, multi-scale information in frequency domain and time domain of the signal can be extracted as the characteristic vectors. After choose and optimization of the eigenvectors based on the method of F-score, support vector machines are used to classify these eigenvectors of power quality disturbances. Effectiveness of the proposed method is verified through Matlab simulation.

Abstract: With the continuous development, the gas well productivity will decrease. The deliverability test can be used to evaluate gas well productivity, but this method always needs long test which will affect daily production seriously, especially for low permeability gas wells, also there always isn’t enough data in the field. Aiming at this problem, this article presents a new real time method to get the gas well productivity. This new method avoids deliverability test and only needs daily production and wellhead pressure data, so the analysis process is easy and this method has strong practicality. It is proved that this new method works well in the field case.