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Because of the high strength and sound stability, the cement stabilized base has been widely used in high grade pavement in China. But shrinkage cracking are easy to occur in the cement stabilized base. Under the repeating action of traffic loads and temperature loads, this kind of cracks are easy to propagate towards the asphalt surface, being called “reflective crack”. Shrinkage cracks are not normally avertable in the cement stabilized base, in contrast with a few wide cracks of broad spacing, numerous thin cracks of narrow spacing contribute little to the severe reflection cracking. On the basis of this thinking, the pre-cracking technique as a promising approach is brought forward. Several vibratory roller passes to the cement-treated base at a short curing stage, typically 1 to 3 days after placement, to create a fine network of cracks, which avoids the wide and/or long cracks and creates the ideal crack model. Comparing to wide cracking, the degree of the stress concentration resulting from thin cracking is by far mitigated. The Finite Element Method is used to predict the ideal crack model, and then the mechanical responses of the semi-rigid pavement of single wide cracking and net hairline cracking under vehicle loading are numerically simulated, simultaneously compared and analyzed. The simulation analyses indicate that the pre-cracking technique is a very useful tool to mitigate the reflective cracks.

Knowledge reduction is one of the basic contents in rough set theory and the most challenging problem in knowledge acquisition. In this paper, an algorithm is proposed, which aims to get all the reducts based on the attributes of the formal context. Experiments show that the algorithm is sound and accurate. Finally, further work and future perspectives are discussed.

Formal Concept Analysis (FCA) is well-founded mathematical theory which has been widely used for many AI needs such as software engineering, knowledge processing, ontology engineering etc. This is a survey paper in which we analyze recent literature on FCA and some closely related applications using FCA. Finally, the new trends and future perspectives are discussed.

The problem of a piezoelectric screw dislocation emitted from a blunt crack is dealt with in this paper. For an arbitrary distribution of the residual dislocation, the series-form solutions are derived. The results show that the force acting on the dislocation decreases with the value of the dielectric constant within the crack increasing. And the increase of the dielectric constant within the crack helps dislocation emission effectively.

The use of immune systems in intrusion detection has been a hot spot of research for the past decade. Immune systems have many features that are desirable for the imperfect, uncontrolled, and open environments in which most computers currently exist. It is hoped that biologically inspired approaches in this area, including the use of intelligent agents will be able to meet this challenge. In this paper, we extract some useful mechanisms from natural biological systems together with the use of intelligent agents, in order to develop cost effective computational solutions to complex problems in artificial immune systems. Analysis and evaluation of the system shows that it is robust, fault-tolerant and has low error rate and high detection rate as well.

An improved UWB non-coplanar power divider is presented. To improve the performances of the power divider, a tapered slot and a fan-shaped slot are used in the circuit design. The simulated results show a better return loss of input port.

Scientific assessment of tourism environmental carrying capacity is key to geotourism sustainable development. Based on exploring the definition of tourism environmental carrying capacity of geoparks and its characteristics, by adopting methods of AHP and literature review this paper focuses on establishing an appraisal indicator system of tourism environmental carrying capacity of geoparks. However, its more reasonable to give weights of appraisal indicators for a given geopark for geoparks greatly differ in terms of natural, economical and socio-cultural environment. Thus, taking Xinwen Karst World Geopark in Sichuan province as an example, the paper calculates weights of indicators of the parks tourism carrying capacity with AHP method and measures its tourism environmental carrying capacity by using average weighted method. The findings reveal that Xinwen Karst World Geopark is in mild overloading.

The paper concluded the Grammatical Structure and standardized application in VRML, summarized the method of realizing complex modeling by using ElevationGrid node, and gave the test program based on the method, and then served for the complex modeling of VRML.

It is important for human-computer interaction smoothly with viewpoint controlling in complex virtual space based on VRML. Analyses the application characters of viewpoint during the realization of 3D models with VRML, and researches the methods of viewpoint control from the point of the viewpoint interactive technology of 3D models, focuses on approach of viewpoint control using Viewpoint node and NavigationInfo node, and provides the demos of the relevant VRML programs.

The paper presented a conventional sequential Structure from Motion method, introduced the algebraic concepts and the core techniques used effectively. It is especially essential to comprehend the static scene based sequential of Structure from Motion is extended to a simultaneous segmentation and reconstruction scheme for dynamic scenes. The first outcome is the multiple view geometry, the second is the feature tracking and geometry initializing, and the last is self-calibration.

Security and stability are important for interactive behavior of virtual object in the virtual environment. To achieving a effective method for region limit to all virtual models is the key to secure and stable virtual environment. The paper analyzed the principle and approach of limit to model behavior region, presented a method based on VRML with validations. The method is effective for safe, stable human-computer interaction in virtual environment, and served for VR-based products design, process approach, and accurate evaluation.

A cleaning robot for household cleaning is designed based on the single chip microcomputer AT89S51. It can complete home environment clean in the case of unattended. With the help of the infrared sensor and the control system, the Cleaning robot can automatically avoid the static and dynamic obstacles in the working environments and clean the ground in the room. Practice has proved that its structure is compact, flexible, easy to implement and control and it can initially complete the obstacle avoidance and cleaning tasks.

Based on Fischertechnik combination model platform, A type of welding robot is designed and developed. Firstly analyzed the overall structure of the robot to determine the driver program and drive programs, and then assembled and establishment the robot structure in accordance with the modular design finally studied the robot control system. This paper focuses on the hardware design of the robot and control system. Practice has proved that the teaching robot we designed has good promotion and application prospects in the field of teaching.

Dayantang slope was stable before Shuibuya project construction. Based on the long-term safety monitoring, it has appeared the obvious deformation during the project construction. According the monitoring datas, the stability of the landslide before and after the construction was discussed and analyzed. Considering the rainfall effect on landslide after it has been strongly anthropogenic disturbance, the numerical results show that it is in critical steady state without rainfall, while get worse and even unstable failure under the influence of the intensive rain and the long period of rainfall.

This work studies the two-photon luminescence spectra of a Yb3+doped YAG crystal grown using the Czochralski method. To study the spectral performance of a 50 at.% Yb:YAG crystal, intense green light (centered at about 544nm) was generated by the crystal upon excitation using a 973nm InGaAs LD pump source. The luminescence spectra were obtained for various Yb concentrations and the emission intensity were plotted versus Yb3+concentration. The green emission light attributed to Yb3+two-photon transition.

Automatically extracting keywords from webpage is greatly important for focused spider. There are already quite many researches on automatically extracting keywords from content-intensive web pages. However, it is still a challenge to extract keywords automatically from hyperlink-intensive web pages (hub pages). The web page author will often use all kinds of visual strengthening means to prominently demonstrate some glossaries connected with the subject. Therefore, this paper proposes a visual model of web pages, DOM-PIXEL, which regards DOM leaf node of webpage as an image element expressed by a vision vector, in which each component corresponds to one visual emphasis means; the pixel value is from the visual energy. The pixel value reflects the relevance of the corresponding DOM node with respect to subject. These parts strengthened by page author will be highlighted with particular “color” in DOM-PIXEL image. Then, the only request for keywords extraction algorithm is to find these “particular points” with particular “color” automatically. Just because of the intrinsic anti-noise ability of DOM-PIXEL and its visual energy transfer rule, the visual model based keywords extraction algorithm (VisualKEA) proposed in this paper significantly promotes the performance on hub pages.

Two kind of polyimide/silica nanocomposites which were recorded poly(amic acid)/ silica(PAA/SiO2) and SiO2in poly(amic acid) ammonium salt(PAS/SiO2) respectively, have been prepared for different methods. The size of SiO2in PAA/SiO2and PAS/SiO2are measured by Particle size analysis and the average particle size are 377nm and 53.7nm. Transmission electron microscopy(TEM) images of PAS/ SiO2confirm that the size of particles are ranged from 40 to 80nm. The stuctures of samples have been characterized by FT-IR spectra. The thermal stability of PAA/SiO2and PAS/SiO2are studied by thermogravimetric analysis (TGA) and the thermal behaviors were investigated by differential scanning calorimetry (DSC) in this paper. It is shown that PAA/SiO2have slightly better thermal properties than that of PAS/SiO2. The results obtained from Instron universal strength tester present the water-solube PAS/SiO2own the excellent mechanical prperties as same as PAA/SiO2.

This paper proposes to verify and test the vibration of diesel’s undercarriage got by virtual measure and actual measure through the analysis of time domain characteristics and amplitude frequency response characteristics of three-orientation vibrant speed of diesel’s undercarriage, represents the difference in time domain characteristics and amplitude frequency response characteristics got by virtual measure and actual measure, expounds the reasons of difference and puts forward a method to diminution the difference. It proves that virtual measure can replace actual measure in a way, though there are some difference in existence, we can erase these difference to the best of ours’ abilities through enough analysis.

A special bifilar 40t electroslag remelting(ESR) furnace for slab products has been fabricated to produce heavy plates for special application. The slab ingots were rolled to heavy plates, and then the mechanical properties of which were investigated. The impact toughness of heavy plates with different position, directions and under welding condition were performed at the temperature ranging from -70°C to room temperature. The tensile experiments at room temperature were carried out to check the tensile properties of heavy plates in different position, directions and under welding condition. The secondary cooling technology developed improves greatly the quality of solidification. Adjusting taper of the mold and using CaF2-CaO-Al2O3-SiO2-MgO slag are necessary for improving surface quality of the ESR slab. The ESR slabs with the maximum thickness of the world in size of 980 mm thickness, 2000 mm wideness and 2800 mm length have been produced successfully. The heavy plates with 410 mm in thickness can be obtained after rolling the 40 tons ESR slabs. The results of mechanical properties show that the heavy plates produced by ESR furnace for slab products exhibits excellent ductility, impact and isotropic properties in different position, directions and under welding condition.