Applied Mechanics and Materials Vol. 577

Abstract: This paper focused on three common diseases, respectively, bacterial leaf spot, black spot and downy mildew as research targets, developed and designed a system to diagnose leaf diseases of sunflowers based on image identification. The system used MATLAB as platform and developed the system by utilizing GUI tool kit. Passing several tests, the system was believed to be able to identify three types of sunflower diseases effectively, respectively, bacterial leaf spot, black spot and downy mildew. The results basically met the requirements set before the design of this system.

Abstract: The vertical directivity characteristic of ambient noise is one inherent characteristic of the ocean in shallow water. And it includes the information of guide’s acoustic characteristic information. The marine guide is composed of sea water; seabed and surface boundary, there into, the acoustic parameters of seabed are hardly obtained exactly. In this paper, the model of vertical directivity for ambient noise is established. Based on the ray theory of sound propagation, the influence of guide’s acoustic parameters which include sound speed, density and attenuation coefficient on vertical directivity of marine ambient noise is simulated. The results are propitious to analysis and command the characteristics of ambient noise, and valuable to accelerate the exertion of acoustic equipment performance.

Abstract: This paper presents a method for multi-point vibration location near-surface. Unlike traditional source location technologies, it is not using travel times of seismic waves for positioning calculation, but according to the entire seismic data record, using the wave equation migration method to calculate the source location. Similar to exploration seismic, the records from a survey line within a certain period of time are data volumes with dimensions of time and ground coordinates. Based on the data, combined with surface seismic wave propagation characteristics, by using the improved seismic depth migration algorithm, the vibration energy will return to the starting position where exactly the source location is. The method can solve the problem of location calculation error by using traditional method when several vibration at the same time or continuous vibration occurs at some point.

Abstract: Hubei Shiyan is the largest city in the source of South to North Water Diversion Project in China. The City District has 100 km of river, along cross-strait with high-rise buildings, dense population, and coverged sewage straight flow to the river. In our paper, the design of "Ming change dark" river closure project can fundamental solve the city environmental pollution problems, improve the source water quality without any menace from the "rear", and make Shiyan's green economy grow rapidly. On the other hand, this "city agriculture" new thinking will completely change the serious situation of arable land area which is decreasing year by year in the world.

Abstract: Relational analysis method was a data process method used to sort out the correlation extent of effect factors in a system with uncertain information. Common mathematical methods were not applicable for describing the relationship. A new method, equivalent numerical relational degree (ENRD) model was developed to evaluate the effect of different factors on air pollution. The effects of different factors-the port throughput, amount of coal, industrial output, and motor vehicle ownership, investment in fixed assets, real estate development and construction of housing construction area on the quality of atmospheric environment were studied. The degrees of correlation were calculated according to ENRD and the values of the port throughput, amount of coal, industrial output, motor vehicle ownership, investment in fixed assets, real estate development and construction of housing construction area were 0.7947, 0.7943, 0.7289, 0.7238, 0.6702 and 0.6527, respectively. From these values, the relations of these factors to the quality of atmospheric environment could be described and evaluated, and the port throughput and amount of coal were relatively major.

Abstract: Recently, the natural mineral resources became short. In the process of fluorite floatation and tailing recycling, the key point is to find out collectors which have good selectivity to fluorite and effective inhibitor of gangue. Most reagents primarily come from agricultural byproduct and some chemical byproduct. However, the tailing mineral is complex and difficult to collect, which brought out accumulation of tailing mineral and water polluted. We try to modify the fluorite collector by use of computer-aided design drawing software and molecular mechanics curve between reagents and useful components in mineral and screen the best reagent. Interaction energy between drugs and fluorite surface is simulated and calculated by molecular mechanics at the atomic level. To determine that the interaction energy between collector and mineral simulated and calculated by molecular mechanics is helpful for demonstrating interaction mechanism. Finally, the better use of tailing mineral is good for environment pollution.

Abstract: Based on the original literature on biomaterials included in Web of Science between the year 1985 and 2012, this paper conducts the author co-occurrence and co-citation analysis, makes the high-frequency co-authors map and co-citation map, and shows the researchers distribution, with the information visualization software CiteSpaceII. By detecting the leading researchers in the biomaterials field, it helps the researchers to comprehend the research fronts and hot research topics quickly, identify classic literature efficiently, and write the literature review in their research activities easily. It provides the experts research direction to view related documents in the vast amounts of data. Moreover, the research result of this paper can provide a basis for relevant government departments to establish the expert database in the biomaterials field.

Abstract: A wireless portable electroencephalogram (EEG) recording system for animals was designed, manufactured and then tested in rats. The system basically consisted of four modules: 1) EEG collecting module with the wireless transmitter and receiver (designed by NRF24LE1), 2) filter bank consisting of pre-amplifier, band pass filter and 50Hz trapper, 3) power management module and 4) display interface for showing EEG signals. The EEG data were modulated firstly and emitted by the wireless transmitter after being amplified and filtered. The receiver demodulated and displayed the signals in voltage through serial port. The system was designed as surface mount devices (SMD) with small size (20mm×25mm×3mm) and light weight (4g), and was fabricated of electronic components that were commercially available. The test results indicated that in given environment the system could stably record more than 8 hours and transmit EEG signals over a distance of 20m. Our system showed the features of small size, low power consumption and high accuracy which were suitable for EEG telemetry in rats.

Abstract: A computer-assisted minimally invasive cochlear implant system is developed to help doctors perform minimally invasive cochlear implant to avoid disadvantages of traditional complex operation like large invasive and long time to recovery et al. Virtual space visualization, space mapping and operation path plan, mechanism for drill positioning and holding are realized with multi-use of computer navigation and virtual space visualization technology and screw theory. Totally 6 cadaveric skull specimen experiments are performed. In experiments, all cochleae are opened perfectly without facial nerves damaged. The results demonstrate that the computer-assisted minimally invasive cochlear implant system can meet the clinical operation demands.

Abstract: Imbalance miRNA target sample data bring about the lower prediction accuracy of SVM(Support Vector Machine). This paper proposes an SVM algorithm to predict the target genes based on biased discriminant idea. This paper selects an optimal feature sets as input data, and constructs a kernel optimization objective function based on the biased discriminant analysis criteria in the empirical feature space. The conformal transformation of a kernel is utilized to gradually optimize the kernel matrix. Through the comparative analysis of the experimental results of human, mouse and rat, the imbalance SVM with biased discriminant has higher specificity, sensitivity and prediction accuracy, which proves that it has stronger generalization ability and better robustness.