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For a weakly nonlinear autonomous systems, the nonlinear coordinate transformation is provided in the form of power series expansions and the mathematical transformation from the physics system coordinate to the modal coordinate is presented. And then, according to the relations between physics system coordinate and modal coordinate, a method of nonlinear modal superposition is obtained. Using this method, the general solution of the vibration under any initial condition can be answered. In order to explain the applications of the method, numerical examples are presented in this paper.

In order to visualize pronunciation teaching and explore the law of articulation evolution in TCFL (Teaching Chinese as a Foreign Language), we proposed an approach to design a physiology Mandarin speech corpus for the international preparatory students in China. Preparatory students are usually beginners to learn Mandarin, so they are selected as testers to gain the most real law of Mandarin articulation evolution. The corpus was different from an ordinary speech corpus. It consisted of not only text information (such as age, gender, nationality, mother language, Mandarin learning experience, etc.) and audio information, but also the physiological data (such as speech organs’ moving morphology). When the corpus was constructed, data were gathered by a supersonic collecting system because of its safety and low cost. In the initial experiment, 21 initial consonants, 36 simple or compound vowels and tones were tested. The results showed the corpus was significant in Mandarin teaching.

Controlling home appliances through network, as one hot topic in the Internet of Things, can provide a way of convenient remote control of home applications. It will greatly improve the user experience and free users from the tedious and redundant controlling actions. In addition, the potential of home appliances network also reflected in the home security and energy conserving and environment protective. Since remote control and user authentication can effectively help to guarantee the home security and a centralized device control is more effective to reduce energy consumption and waste of resources. "My Private Housekeeper" is a novel network-based appliance control system. In this paper, by taking several popular household appliances as example, we describe the system design and implementation in details. Using the Atom platform as the control center, our system can remotely and locally control equipments on real time through wireless technology and voice interface. The mechanism used on mobile platform, which is connected to the Internet, is similar to instant messaging. The voice control part is based on MST omnidirectional microphone, which can capture sound signal within a radius of 5 meters, and keep sound quality for speech recognition. This system uses the XML-based device description and control protocol, which was designed and developed by our group, to implement device self-describing and control information response.

n this paper, we proposed a mobile security system based on IP camera network video surveillance by improving the traditional monitoring methods. This system includes three parts: Android mobile client, cloud server, IP camera monitoring terminals. By setting IP cameras at 24 fps but only sending one frame each second, we can infer the situation by analyzing of the single image and reduce the amount of data transmission. User can check the live scenes and send control commands to monitoring terminal or receive the push information from the server to freely give alarm signal to users anytime, anywhere. And users can also select any regions or any specific objects to monitor, the server will real-time monitor each scene according to the specific requirements by using the algorithms of image contrast and depth estimation. The experiment results show that the system can greatly improve the accuracy of the alarm.

World Model is the robots view of the world and contains information for the robot to make decisions. World Modeling is the process that robots map the sensor data into the World Model. The complexity of the sensors increased, so does the data process components. In this paper, an architecture for world modeling is proposed. This architecture enhances the extensibility of the data process components by decoupling them with a middleware, and it improves the efficiency by computing in parallel. The combination of this architecture and the PDDL will also be presented.

This Paper will introduce methods used to resolve self-location problem of humanoid robots. There are two method that will be mentioned in this paper. A traditional method which uses marks and flags on the soccer field for robot location will be introduced at first. This paper will also discuss how to solve the singularity problem in traditional self-location method. The optimization self-location method which uses sidelines on the soccer field will be introduced at the same time. This paper will introduce how to mapping the field sidelines in vision to the field sidelines of soccer field. This method is implemented and tested in Robocup 3D Soccer Simulation League. The results show that the accuracy of self-location method will be increased by taking full use of soccer field sidelines in vision information.

In order to locate the sound source based on the microphone uniform linear array and reduce the impact of noise and reflection, improved multiple signal classification algorithm and a kind of weighted average filters be used in this paper. According to the microphone array speech processing characteristics, we improved the traditional multiple signal classification algorithm and designed a kind of weighted average filters. Then, we made the computer simulation experiments. The experimental results show that the location of the sound source is the peak with the highest power in the spatial spectrum. Besides, the frequency domain diagram is more smoothly and the power of the noise and reflection is effectively reduced except sound source through the weighted average processing. Therefore, improved multiple signal classification algorithm can achieve sound source localization based on the microphone uniform linear array. And the impact of the noise and reflection is effectively reduced by processing of the weighted average filters.

To evaluate the pre and post change of structure strength of old asphalt pavement field hot regeneration, we use the portable falling weight deflectometer method (PFWD) and benkelman beam method (BB) respectively to do the field test research. The field test researches rely on the ANXIN highway old asphalt pavement field hot regeneration project. We got the data about pre and post regenerations asphalt pavement static bending deflection (l0), PFWD dynamic deflection (lp) and PFWD dynamic modulus (EP). The correlation analysis among static bending deflection, PFWD dynamic deflection and PFWD dynamic modulus suggest that PFWD method is a more stable and reliable method than BB method and PFWD method can be a new evaluation technology for the old asphalt pavement field hot regenerations pavement strength.

Phytochemical investigation of the aerial parts of Euphorbia sikkimensisled to the isolation of one new diterpenoids, named sikkimenoid E (1), together with thirteen other known compounds (2–14). Their structures were established by means of spectroscopic methods. Compound 2was identified to be a trinortriterpenoid, and derived for the first time from a natural source. In this paper we reveal for the first time its comprehensive spectral data and NMR spectral assignment. Compound 4showed antiangiogenic activity with an IC50value of 5.66 µM in a zebrafish model, and compounds 5and 6exhibited cytotoxicity toward A549 cell line with IC50values of 12.12 and 6.45 µM, respectively.

In this research, we present a Case-Based Reasoning framework for planning the best path of navigation robot. That is to adopt the combination of the Case-Based Reasoning method and ontology approach to disambiguate the cases in the context. The details of realizing the best path planning of robot by using this architecture was illustrated. Our approach for realizing case-based reasoning implies the representation of metadata characterizations of the features of cases and semantic formalization of these characterizations.

In this paper, the middle-span space truss is chosen as the research object, and viscous dampers are introduced into the space truss as damping elements. The method of “fast non-linear analysis (FNA)” is adopted to numerically simulate the dynamic response. The better selection of the layout, number and damping index of dampers is intensively studied. Finally, more economical and practical results of damping design with viscous dampers are achieved, which can provide a reference for the design of the same kind of structure.

The combustion rates of carbon particle in pressurized oxygen-enriched environment were studied. The combustion rates of different diameter carbon particles were calculated in atmospheric as well as pressurized oxygen-enriched conditions. The effects of pressure and particle size on combustion rate of carbon particle were investigated. It shows that the combustion rate of carbon particle rise with the increase of the pressures in pressurized oxygen-enriched and pressurized air conditions. But, the combustion rate of carbon particle change little at higher pressure. When particle size increased from 50μm to 100μm，the combustion rate of carbon particle rising. When the particle size increased to 150μm, the combustion rate of carbon particle changed little.