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In recent decades, as aging population and empty-nest families are increasing, falls in the elderly have become the health care issues that cannot be neglected. The computer vision-based methods are promising for fall detection, for they apply a camera installed indoors to monitor the movement of the elderly in real time. However, the features used in previous methods lack specificity, thus they have difficulty in distinguishing falls from some normal activities, such as crouching down. In this paper, we propose a novel fall detection method based on semi-contour distances for monitoring elderly people in the home environment. Firstly, we use the Gaussian Mixed Model (GMM) method to extract the human silhouette; then capture the geometric features, i.e. the semi-contour distances of the human silhouettes; finally apply the SVM classifiers to classify different actions to complete fall detection. The experimental results demonstrate that the accuracy of this algorithm is 86.79% and the sensitivity is 96.87%. It is shown that the proposed video-based fall detection method could achieve a reliable result.

The satellite signals are always blocked by obstructions in urban canyons, therefore multi-constellation global navigation satellite system (GNSS) performs poor. Quantitative comparison of the performance of different satellite navigation systems can provide a basis to analyze their advantages and disadvantages. This paper proposes a fuzzy comprehensive evaluation (FCE) theory to quantitatively evaluate the performance of GNSS, and systematically puts forward how to quantitatively analyze precision, availability, continuity and integrity. A simulation was conducted to emulate the environment of urban canyons. Evaluation results show the performance of BDS is neck and neck with GPS, and much better than GLONASS. A multisystem has better performance than a single system. GPS+GLONASS+BDS has the best performance and gets a high FCE result of 0.3268, while the FCE result of GPS, BDS and GLONASS are 0.1722, 0.1570 and 0.0970 respectively.

According to different image completion purposes, we divide it into two different kinds of circumstances. For different situations, we use different fusion technology to achieve image completion, then we present a new framework for image completion based on image fusion technologies.

We describe a 10-year-old Chinese girl with blurred vision in her left eye over a month and an optic nerve “mass” of her left orbit shown on computed tomography. The patient was initially misdiagnosed as having a retrobulbar tumour. However, detailed fundus examination showed a very deep excavation surrounding the disc and magnetic resonance imaging revealed excavation of the posterior wall connected to the vitreous cavity. These findings suggested a diagnosis of peripapillary staphyloma. The reasons for the misdiagnosis are discussed.

Considering that spatial structural information of images, taken from the same scene even with diverse illustration or in different wavebands, has much in common with each other, we propose an image registration method utilizing similarity of edge information as a new similarity measure. Similarity of edge information can be achieved from gradient information of detected edge pixels in two images, so it reflects well the relevance of spatial structures between two corresponding scenes. Experimental results indicate that, no matter when lighting changes or for images sensed in different wavebands, the proposed similarity measure exhibits a perfect single peak response with respect to transformation parameters and the proposed method achieves more accurate alignment than the one based on mutual information.

Application of nonlinear — load especially power electronic devices in power system causes the increase of harmonics content. It causes greatly harmful to the stable operation of power grids, and power systems equipment. Traditional harmonics monitoring system is mainly based on hardware, Because of its simple function; it has a lot of disadvantages. This paper presents a design scheme of harmonics measurement and analysis system based on LabVIEW and FFT (fast Fourier transformation). The method of Detection, the composition of hardware and the harmonic measurement and analysis module block diagram are introduced.

Using the fast discrete curvelet transform, an image fusion algorithm based on adaptive pulse coupled neural networks (PCNNs) is proposed. PCNN is built in each high-frequency subband to simulate the biological activity of human visual system. Support vector machine is employed to achieve support values which represent subband features and then will be imported to motivate the neurons. The first firing time of each neuron is presented as the salience measure. Compared with traditional algorithms where the linking strength of each neuron is set as constant or always changed according to features of each pixel, in our algorithm, the linking strength as well as the linking range is determined by the prominence of corresponding low-frequency coefficients, which not only reduces the calculation of parameters but also flexibly makes good use of global features of images. Experimental results indicate superiority of the proposed algorithm in terms of visual effect and objective evaluations.

This study has been performed in order to analyze the coordinated degree and evolving trends of the land intensive use and land eco-security based on the statistical data from 1998 to 2007 in Chengdu city by Synergetios theory and dynamic coordinated degrees model. Results show that during the study period, the level of land intensive use and land ecological security both rose in Chengdu, the former continuing to raise, the overall increasing but some fluctuations in the latter. Dynamic coordinated degree in 10 years is between 8.99°~57.71° with a trend of rising firstly then dropping, undergoing the process from a relatively harmonious development to the best coordinated development, then to less coordinated development. From 2005, the coordinated degree between the two systems began to decline.

According to features of multifocus images and statistical characteristics of contourlet coefficients, a novel algorithm for multifocus image fusion based on contourlet hidden Markov tree model (con-HMT) is proposed. Multifocus images are used all together to train the contourlet HMT model. Then a new fusion rule for the high frequency is built. In this rule, the probability of a detailed coefficient corresponding to image edge, calculated directly from the HMT model, is chosen as the salience measure. Experimental results show that, for multifocus image fusion, the proposed algorithm provides more satisfying fusion results in terms of visual effect and objective evaluations, which proves its feasibility and validity.

Annealing effect on the performance of fully transparent thin-film transistor (TTFT), in which zinc tin oxide (ZnSnO) is used as the channel material and SiO2 as the gate insulator, is investigated. The ZnSnO active layer is deposited by radio frequency magnetron sputtering while a SiO2 gate insulator is formed by plasma-enhanced chemical vapor deposition. The saturation field-effect mobility and on/off ratio of the TTFT are improved by low temperature annealing in vacuum. Maximum saturation field-effect mobility and on/off ratio of 56.2 cm2/(Vs) and 3 × 105 are obtained, respectively. The transfer characteristics of the ZnSnO TFT are simulated using an analytical model and good agreement between measured and the calculated transfer characteristics is demonstrated.

To obtain the relationship between the absorptances of thin-film materials and the incoming ultraviolet laser energy density, it is better to establish a standard measurement method. The principle and measurement process of laser calorimetry is introduced, the dose depending effect, nonlinear absorption, and unrecoverable absorption phenomenon that might influence the measurement results are analyzed, a method based on the laser calorimetry is proposed, which is used to measure the absorptance of fluoride coatings that can be used in 193 nm ultraviolet photolithography systems, and experiments. According to the new proposed method, the dose depending effect, the corresponding laser energy density while the unrecoverable absorption phenomenon appears when the fused silica substrates are irradiated by 193 nm laser are measured; the relationship between absorptances of substrates and the laser energy density are calculated. After that, two substrates are coated with LaF3 and MgF2 separately by boat evaporation; the relationships between absorptances of the coated samples and laser energy density are measured. By the comparison of absorptances before and after coating, the relationships of the two thin-film materials between absorptances and laser energy densities are calculated, and the absorptances of LaF3 and MgF2 in actual working condition are figured out, also the relationship between deposited temperature and absorptance, roughness, waviness of LaF3 is obtained. The experimental results confirm the feasibility of the proposed method, which help to improve the imaging quality and prolong the working life of the objective system that can be used in the photolithography system.

Considering statistical characteristics of multiwavelet coefficient vectors, an image fusion method with a window-based salience measure for vector fusion is proposed in the multiwavelet domain. After analyzing joint probability distribution of multiwavelet coefficient vectors, we respect the joint probability distribution as a peaky and heavy tailed two-dimensional non-Gaussian distribution, and hence model it by using a bivariate symmetric alpha-stable ( BiSαS ) distribution. Model parameters of the BiS α S distribution can be estimated from samples of multiwavelet coefficient vectors. In a sliding window, the estimated parameters can reveal the impulsive shape of the histogram of the multiwavelet coefficient vectors within the window. So we employ these model parameters to form the new salience measure indicating the degree of prominent information. In our method, vector fusion rule is introduced to avoid inconsistency of decision maps between the component sub-bands and, consequently, to lessen ringing artifacts in final fusion results. Experimental results support the effectiveness of our proposed method in the area of visual quality and objective evaluations.

We propose an image fusion method robust to misaligned source images based on their multiscale edge representations. Significant long edge curves at the second scale are selected to decide edge locations at each scale for the multiscale edge representations of source images. Then, processes are only executed on the representations that contain the main spatial structures of the images and also help suppress noise interference. A registration process is embedded in our fusion method. Edge correlation, calculated at the second scale, is involved as a match measure determining the fusion rules and also as a similarity measure quantifying the matching extent between source images, which makes the registration and fusion processes share the same data and hence lessens the computation of our method. Experimental results prove that, no matter whether in a noiseless or noisy condition, the proposed method provides satisfying treatment to misregistered source images and behaves well in terms of visual and objective evaluations on the fusion results, which further verifies the robustness of our edge-based method to misregistration and noise.

Considering the reality of image formation as well as the statistical characteristics of contourlet coefficients, we propose a method for statistical image fusion in the contourlet domain. For high-frequency subbands, an image formation model was established that has a continuous-valued blur factor to reflect the actual imaging situation. According to this model, fused contourlet coefficients were estimated by use of an expectation-maximization (EM) algorithm. During the estimation, a contourlet hidden Markov tree model was adopted to grasp all dependencies among coefficients and aim for better estimation results. Because the blur factor is a continuous variable, we exploited an explicit expression to update the factor in the EM algorithm, which contributed to a decline in the number of iterations for convergence. Experimental results indicated that, especially for multifocus images, the proposed method provides more satisfying fusion results in terms of visual effects and objective evaluations than some typical fusion methods based on multiscale decomposition and some statistical fusion methods using a discrete blur factor.

Indium zinc oxide (IZO) thin films with different percentages of In content (In/[In+Zn]) are synthesized on glass substrates by magnetron sputtering, and the structural, electrical and optical properties of IZO thin films deposited at different In2O3 target powers are investigated. IZO thin films grown at different In2O3 target sputtering powers show evident morphological variation and different grain sizes. As the In2O3 sputtering power rises, the grain size becomes larger and electrical mobility increases. The film grown with an In2O3 target power of 100 W displays the highest electrical mobility of 13.5 cm·V−1·s−1 and the lowest resistivity of 2.4 × 10−3 Ω·cm. The average optical transmittance of the IZO thin film in the visible region reaches 80% and the band gap broadens with the increase of In2O3 target power, which is attributed to the increase in carrier concentration and is in accordance with Burstein—Moss shift theory.

We report on the study of CdSe quantum dot microcavity formed between two distributed Bragg reflectors (DBRs). The active region consisting of CdSe quantum dots is embedded in PMMA. We use the transfer matrix method (TMM) to simulate the reflectivity spectrum of the microcavity. We demonstrate an enhancement of the spontaneous emission from the colloidal CdSe quantum dots in the microcavity. After embedding the QDs in the cavity, the full width at half maximum (FWHM) is narrowed to 7.5 nm compared with 27.9 nm of QDs in free space. The emission of the quantum dots is enhanced by a factor of 3.7 due to the microcavity effect.

Thin film transistors with zinc tin oxide as the active channel layer were fabricated on ITO glass by rf magnetron sputtering. SiO2 gate dielectric was grown using plasma-enhanced chemical vapor deposition (PECVD). These devices operate with a maximum field effect mobility of 9.1 cm2/V ·s, threshold voltage of -2 V, and current on/off ratio of 104.

This paper discusses a method of characterizing the gain of the laser pulse amplifier using its gain fluence curves,and studies gain fluence curves of a single amplifier.These help us to understand the characteristics of the amplifier and provide a powerful tool for the investigation of the power balance.

Power balance between laser beams is important for high_power l aser system. This paper uses a calculation method as an exact solution for laser-amplification to simulate the output pulse shape of “Shenguang Ⅱ" laser facility. The results are preferable, as compared with the results of the experiments .

A three-plate identical ring interferometer is a white-light interferometer with constant lateral translation shearing, and its precision of measurement corresponds to the depth of focus. The grating spatial filter system directly gives the information of the distortion quantity in the wavefront, and is also applicable to diagnostics of small-aperture light beams.

The distribution and excretion of intravenous injected3H-rhomotoxin was studied in mice. The radioactivity of3H-rhomotoxin was found to be high in gall bladder, liver and kidney, lower in thyroid gland, adrenal gland, heart and lungs, and lowest in brain. 52.4% of the drug was excreted in urine and feces within 6 h. Rhomotoxin was bound to plasma protein (60 % at 30 min) and to some extent to liver and kidney tissue.