Traditional texture region location methods with Gabor features are often limited in the selection of Gabor filters and fail to deal with the target which contains both texture and non-texture parts. Thus, to solve this problem, a two-step new model was proposed. In the first step, the original features extracted by Gabor filters are applied to training a self-organizing map (SOM) neural network and a novel merging scheme is presented to achieve the clustering. A back propagation (BP) network is used as a classifier to locate the target region approximately. In the second step, Chan-Vese active contour model is applied to detecting the boundary of the target region accurately and morphological processing is used to create a connected domain whose convex hull can cover the target region. In the experiments, the proposed method is demonstrated accurate and robust in localizing target on texture database and practical barcode location system as well.

In order to evaluate all attack paths in a threat tree, based on threat modeling theory, a weight distribution algorithm of the root node in a threat tree is designed, which computes threat coefficients of leaf nodes in two ways including threat occurring possibility and the degree of damage. Besides, an algorithm of searching attack path was also obtained in accordence with its definition. Finally, an attack path evaluation system was implemented which can output the threat coefficients of the leaf nodes in a target threat tree, the weight distribution information, and the attack paths. An example threat tree is given to verify the effectiveness of the algorithms.

Tracking tests for different polymer materials were carried out to investigate the chaotic behavior of surface discharge. The discharge sequences measured during the discharge process were analyzed for finding the evidence of chaos existence. Four kinds of nonlinear analysis methods were adopted: estimating the largest Lyapunov exponent, calculating the fractal dimension with increasing the embedding dimension, drawing the recurrence plots, and plotting the Poincaré maps. It is found that the largest Lyapunov exponent of the discharge is positive, and the plot of fractal dimension, as a function of embedding dimension, will saturate at a value. The recurrence plots show the chaotic frame-work patterns, and the Poincaré maps also have the chaotic characteristics. The results indicate that the chaotic behavior does exist in the discharge currents of the tracking test.

Fruit ripening is a complex process and is regulated by many factors. Ethylene and polygalacturonase (PG), lipoxygenase(LOX), expansin(EXP) are all critical regulating factors in fruit ripening and softening process. With antisense ACS tomato, Nr mutant tomato and cultivated tomato as materials, Northern blot hybridization showed that PG, LeEXP1 and LOX expressed differently in different parts of cultivated tomato fruit during ripening, which was related to fruit ripening. The ripening process of columella and radial pericarp was faster than pericarp. In both Nr mutant and antisense ACS transgenic tomato fruit, expression levels of PG, LeEXP1 and LOX were generally lower than those in cultivated fruit but still related to fruit ripening. The expression levels of PG, LeEXP1 and LOX increased in the mature green tomato fruits after 0.5 h treatment with ethylene (100 μL/L). These results indicate that gene expression of PG, LeEXP1 and LOX were positively regulated by ethylene. The time and cumulative effect of the concentration exists in the expression of PG regulated by ethylene. The regulation of LOX expression mainly depended on the fruit development after great amount of ethylene was produced. PG played a major role in ripening and softening of tomato fruit, and cooperated with the regulation of EXP and LOX.

Issues of scale and aggregation become important when large range of space and time scales is considered in landscape models. However, identifying appropriate levels of aggregation to accurately represent the processes and components of ecological systems is challenging. A raster-based spatially explicit forest landscape model, LANDIS, was used to study the effects of spatial aggregation on simulated spatial pattern and ecological process in Youhao Forest Bureau of the Small Khingan Mountain in Northeastern China. The model was tested over 500 simulation years with systematically increased levels of spatial aggregation. The results show that spatial aggregation significantly influences the simulation of fire disturbance, species abundance, and spatial pattern. Simulated fire regime was relatively insensitive to grain size between 30.m and 270.m in the region. Spatial aggregation from 300.m to 480.m dramatically decreased fire return interval (FRI) and increased mean fire size. Generally, species abundance and its aggregation index (AI) remained higher level over simulation years at the fine-grained level of spatial aggregation than at coarser grains. In addition, the simulated forest dynamics was more realistic at finer grains. These results suggest that appropriate levels of spatial aggregation for the model should not be larger than 270.m.

The distribution and characteristics of nonmetallic micro-inclusions of GCr15 bearing steel were explored through metallographic area method in virtue of tracer method and electronic microscope. The results show that the micro-inclusions, of which the average value is 0.032%, are mainly the compounds formed via the adsorption/aggregation of multielement deoxidized compounds and secondarily deoxidized products on tundish liquid level. The micro-inclusions of diameters from 0 to 5 μm are 92.5% in total, which basically determines the characteristics of inclusions distribution in casting slab. The inclusions of diameters more than 10 μm only account for less than 1% in total, which have little influence on steel quality. The relationship between equilibrium compositions of the first deoxidation products and molten steel compositions was also calculated based on thermodynamic theory.

A method of topology synthesis based on graph theory and mechanism combination theory was applied to the configuration design of locomotion systems of lunar exploration rovers (LER). Through topology combination of wheel structural unit, suspension unit, and connecting device unit between suspension and load platform, some new locomotion system configurations were proposed and the metrics and indexes to evaluate the performance of the new locomotion system were analyzed. Performance evaluation and comparison between two LER with locomotion systems of different configurations were analyzed. The analysis results indicate that the new locomotion system configuration has good trafficability performance.

An improved cluster thermal time constant (CTTC) and surface thermal time constant (STTC) numerical model was introduced, which took into account the effect of vegetation coverage and modified the expression of net long-wave radiation of the canyon layer. In the case study the model was used to calculate the air temperature variation at downtown of Tianjin City. The relative error between the calculated and measured air temperatures was less than 3%. The tendency of air temperature variation was predicted when the building aspect ratio, vegetation rate, and wind speed changed respectively. It is demonstrated that when the aspect ratio of a building with south-north orientation increased, the heat island intensity at day time was mitigated; however, it became worse after sunset. The vegetation coverage rate and wind speed both had negative relationship with the urban heat island intensity.

Wave motion in subway or tunnel fire is an intrinsic property of smoke. As the pressure of smoke changes with mass of certain power, a kind of linear wave equation for smoke can be derived from the conservation equations of its mass and momentum, under nearly homogeneous zone assumption. The smoke movement of 4 subway fires was simulated with Airpak. By fitting the pressure-mass functions to the simulated data, wave equations of the smoke were derived, and wave motions of smoke were thus validated. It can be seen that smoke wave is a kind of mass wave, whose velocity is inversely proportional to smoke mass, and wave of a bigger fire propagates slower.

The contamination diffusion to the operating room when the door is open was simulated with a computational fluid dynamic(CFD) method, to give the extent of the contamination diffusion. The influence of the door-opening procedure was ignored since the door of the operating room is normally a sliding one. The flow field in the case of the 16 s course of opening the door was simulated. The simulated and the experimental results demonstrate that the extent of the contamination diffusion is around 1.5 m when there is no temperature difference between indoor and outdoor, and there is hardly any contamination diffusion when the temperature difference is 1 °C. It can be concluded that the positive pressure difference in the operating room lost its function in preventing the contamination when the door is open. That the temperature of corridor is lower than that of operating room contributes to contamination control. Keeping 1 °C temperature difference between corridor and operating room and increasing positive pressure and air flow are suggested. It is more secure to set up an anteroom if persons come in or out of the operation room at the course of surgery.

By using the theory of Euclidean Jordan algebras, based on a new class of smoothing functions, the Qi-Sun-Zhou’s smoothing Newton algorithm is extended to solve linear programming over symmetric cones (SCLP). The algorithm is globally convergent under suitable assumptions.

In order to achieve a modulator with broad bandwidth and perfect impedance match, a novel electro-optical modulator based on GeO₂-doped silica waveguides on silicon substrate is designed. The finite element model of the whole electro-optical modulator is established by means of ANSYS. With the finite element method analysis, the performance of the novel modulator is predicted. The simulation reveals that the designed modulator operates with a product of 3 dB optical bandwidth and modulating length of 226.59 GHz·cm, and a characteristic impedance of 51.6 Ω at 1 550 nm wavelength. Moreover, the calculated electrical reflected power of coplanar waveguide electrode is below −20 dB in the frequency ranging from 45 MHz to 65 GHz. Therefore, the designed modulator has wide modulation bandwidth and perfect impedance match.

A series of ablation experiments on silicon surface by femtosecond laser system of 775 nm and 150 fs duration pulses were carried out. The morphological characteristics and the associated effect in the ablation were tested by atomic force microscope (AFM), scanning electron microscope (SEM), focused ion beam (FIB), and the optic microscope. The single pulse threshold can be obtained directly. For the multiple pulses, the ablation threshold varies with the number of pulses applied to the surface due to the incubation effect. By analyzing the experimental data, the thresholds of laser fluences under various laser pulse numbers were obtained, and the relationships between ablation area and laser energy and laser pulse number were concluded. Meanwhile, the periodic ripple structure on silicon surface was found. Under the condition of certain laser power, the number of laser pulse can influence the formation of ripples.

The growth patterns of mammary fat pads and glandular tissues inside the fat pads may be related with the risk factors of breast cancer. Quantitative measurements of this relationship are available after segmentation of mammary pads and glandular tissues. Rat fat pads may lose continuity along image sequences or adjoin similar intensity areas like epidermis and subcutaneous regions. A new approach for automatic tracing and segmentation of fat pads in magnetic resonance imaging (MRI) image sequences is presented, which does not require that the number of pads be constant or the spatial location of pads be adjacent among image slices. First, each image is decomposed into cartoon image and texture image based on cartoon-texture model. They will be used as smooth image and feature image for segmentation and for targeting pad seeds, respectively. Then, two-phase direct energy segmentation based on Chan-Vese active contour model is applied to partitioning the cartoon image into a set of regions, from which the pad boundary is traced iteratively from the pad seed. A tracing algorithm based on scanning order is proposed to accurately trace the pad boundary, which effectively removes the epidermis attached to the pad without any post processing as well as solves the problem of over-segmentation of some small holes inside the pad. The experimental results demonstrate the utility of this approach in accurate delineation of various numbers of mammary pads from several sets of MRI images.