Applied Mechanics and Materials Vols. 644-650

Abstract: Flight duration is a key design issue for the monitoring applications based on the UAVs. Based on the assumption that UAVs often fly at a high altitude, the resolution of images captured by the UAVs is not high enough. Thus, the problem of positioning the UAV can be solved by image matching. When a UAV comes to a certain place that it has ever been to, there are the same objects in the images that it takes currently and a short time ago. We propose a text retrieval like method based on SIFT vectors for computation efficient in image matching. Experiments show that our method is good at discriminating between images taken at different places.

Abstract: Recently, the variety of emergent events frequently occurring, such as: great environmental pollution, fire and explosion, toxic gas leakage, disserves human’s living environment, and huge economic and property losses, especially in the rural areas of mountain, where always surrounding by gas fields, chemical plants and other potentially dangerous source, the terrain of mountainous is complex, in the event of crises, the safe evacuation of the population will become a very critical issue. In this paper, through the analysis of the existing evacuation model based on the proposed application 3D surface cellular automata method simulation the evacuation processin complex mountainous terrain. The digital elevation model data, road network and characteristics of the pedestrian are integrated initiatively in the 3D surface CA model. The framework for data extraction, procession and application is designed. A Visualization Software System for three-dimensional simulation of pedestrian evacuation is developed. Moreover, through a case study of some gas well, which belongs to the Puguang gas field in the northeastern Sichuan, it is proved that the model presented in this paper can realize 3D simulation of pedestrian evacuation and predict evacuation time. At last the future work of the model is discussed.

Abstract: The key point of trajectory basis based Non-Rigid Structure from Motion (NRSFM) is how to tune the basis size and how to choose the best basis combination. If the basis size is too small, the trajectory is poorly represented by the basis. But too large basis size makes the system more ill-conditioned and the reconstruction error becomes unbounded. In this paper, an automatic method is proposed to select the trajectory basis, which can select appropriate basis size. The experiment results show that, compared with the empirical value from a lot of repeated experiments, the proposed method can improve both reconstruction accuracy and efficiency of NRSFM.

Abstract: Usability evaluation of eye-traker based smart phone APP Graphic user interface (GUI) use innovative visual factors separate concept to design three A/B tests, thoes viusal factors are color, icon and layout. Within area of interest (AOI) method collect eye-tracking data by eye-tracker such as time to first fixation on-target, repeat fixations/ post-target fixation, number of fixation per area and percentage of fixation. As a resualt, through test and data analysis find optimal GUI prototype. This usability evaluation method is a new way of APP GUI prototype usability research and is capable of being widely used in relevant research.

Abstract: Red Fuji, Huaniu and Gala were classified by Fourier transform near infrared (FT-NIR) spectroscopy and possibilistic learning vector quantization (PLVQ) which was proposed to solve the noise sensitivity problem of fuzzy learning vector quantization (PLVQ). Firstly, apple NIR spectra were measured by FT-NIR spectrophotometer. Secondly, principal component analysis (PCA) was used to compress the dimensionality of NIR spectra which was high dimensional. Thirdly, fuzzy c-means (FCM) clustering was run to termination to obtain the cluster vectors for PLVQ. Finally, PLVQ was performed to classify the data. Experimental results showed that this classification method was fast, nondestructive and effective for classifying the variety of apples.

Abstract: In order to time grating measurement principle application to the field of optical measurement, a uniform scan coordinate system by using photosensitive element of timing driven is presented to convert the displacement detection of the object into measured time difference. According to the conversion principle of relative motion coordinate systems of time grating, when view the photosensitive element of linear CCD as a uniform scanning coordinate system, view the spatial side by side and timing of mutually staggered on the two linear CCD as a stationary coordinate system, after measured the time difference variation of the output electric signal on the different CCD for the same object, size and direction of the relative displacement of the object would be made by multiplying time difference variation and scanning speed. With the calibration of the Renishaw laser interferometer for the developed linear CCD displacement sensor, the measuring errors are controlled within after error correction in the effective measuring range of 600.05mm. This realizes the idea of time measuring space in the field of optical.

Abstract: Analyzing the parallel synchronous transmission data based on the proposed use of time-multiplexing transmission mode dynamic solve the transmission delay is large, the traditional structure of the software causing the radio frame data are transmitted in parallel low-speed data blocking phenomenon; and problems caused by data transmission and processing delay for virtual radio monitoring system uses asynchronous mode uncertainty, proposed time synchronization method based on the data frame structure to a more generalized approach to achieve a measure of sync.

Abstract: Ultrafast spectroscopy has many characteristics, which has attracted much attention in recent years. It is of high time resolution, rich nonlinear interaction of light and matter. It can be used to regulate the quantum state of matter coherent photons and its derivatives and grafting technology bring a lot of changes in condensed matter physics experiment technology. This article introduces the general principles time-resolved technique and typical configuration of ultrafast spectroscopy. Through specific examples this paper shows its applications in condensed matter physics research.

Abstract: The characteristic of nozzle jeting is affected by injection frequency, gas pressure in the piping and duty cycle of the control signal.The experimental study is in order to determine nozzle’s opening frequency, duty cycle and pipe pressure affect to the gas flow rate using a drainage method, nozzle opening frequency and duty cycle are controled by mototron platform and ATI Vision calibration software,while using pressure transmitter to measure the change of pipe pressure relationship with duty cycle and frequency.

Abstract: The main work of this paper is simulating C-waveband Dual-Wavelength Erbium-Doped Fiber Laser by the Optisystem software, propose different schemes of optimizing output power, and research the influences of different parameters on the performance of the system. At last ,We find that when the length of Erbium-Doped Fiber is at about 4.13m, and the Er ion density is 20e+024m-3, the output power of 1530nm and 1550nm will get the best performance synchronously.