Applied Mechanics and Materials Vols. 66-68

Abstract: The fabrication of metal parts is the backbone of the modern manufacturing industry. Laser forming is the combination of five common technologies: lasers, rapid prototyping (RP), computer-aided design (CAD), computer-aided manufacturing (CAM), and powder metallurgy. The resulting process creates part by focusing an industrial laser beam on the surface of processing workpiece to create a molten pool of metal. A small stream of powdered alloy is then injected into the molten pool to build up the part gradually. By moving the laser beam back and forth and tracing out a pattern determined by a CAD, the solid metal part is fabricated line by line, one layer at a time. By this method, a material having a very fine microstructure due to rapid solidification process can be produced. In the present work, a type of direct laser deposition process, called Laser Metal Deposition Shaping (LMDS), has been employed and developed to fabricate metal parts. The LMDS apparatus consists of four primary components: energy supply system, motion control system, powder delivery system, and computer control system. These components have their specified functions, but work in association with each other.

Abstract: Oral English teaching has been in an embarrassing situation because of lacking necessary language environment. With the development of virtual reality technology, using computer technology to build an English learning environment becomes possible, and thus to change the difficult situation of oral English teaching. This paper first introduces the main contents of the oral English teaching and existing problems, then analyzes the theoretical basis and advantages of college oral English teaching basing on virtual reality technology, and finally puts forward some effective ways that the virtual reality technology applies to oral English teaching.

Abstract: This paper describes the need for development of real-time online teaching evaluation system with the credit management mode, and promotes a new teaching evaluation theory in accordance with the development of credit management.

Abstract: Web3D technology is an implementation of virtual reality technology in the form. This paper researches the theory and mainstream technology of the virtual reality based on Web3D technology, and explores the application of virtual reality technology in distance education, thus to further promote the development of online teaching.

Abstract: Experimental teaching is an important way to cultivate students’ professional qualities. This article first gives an account of the background and significance of developing virtual network lab, and then puts forward a solution to design and implementation of the lab based on the design concept of Web2.0.

Abstract: At present, the development and popularization of computer and network provides English teaching reform and development with new methods and means as well as a broader platform for the implementation of the autonomous, student-centered, individualized teaching model. This paper analyzes the problems in traditional English testing practice, proposes the theoretical basis for testing and training system establishment, and introduces the development process and characteristics of web-based English testing platform.

Abstract: In this paper, we aimed at segmenting industrial computerized tomography images grounded in edge information. Most researchers focused on the edges of binary images using cellular neural network. We have expanded the scope to gray level images. Thus two groups of cellular neural network were designed to obtain closed edges. One was used to convert the gray level images to binary ones, the other to extract edges. In addition, we combined with contrastenhancement. Subsequently, tracing the obtained edges accomplished segmentation. Simulation experiments on a series of engine images demonstrate our methods can not only batch process threshold segmentation without choice threshold, but also extract the fine edges .A comparison to state-of-the-art methods show ours are easy to follow with good results.

Abstract: Name Services for the Internet of Things are distributed systems that serve a fundamental lookup function to identify the distributed data for tracing the product. However,the currently specified Object Naming Service (ONS) for the Internet of Things has severe drawbacks ,such as low efficiency and weak security.In this paper, we Put forward a name service architecture based on Pastry algorithm. And an experiment is carried out by OMNET++ simulation platform , experimental results demonstrate that the mechanism in terms of both network throughput, query efficiency has improved greatly compared to ONS.

Abstract: In this paper we present a CCD image sensor system with high dynamic range. This feature is achieved through double analog-to-digital convertors’(ADC) architecture and field programmable gate arrays(FPGA). By doing so, the system outputs high dynamic range images in real time. The proposed scheme is a low-cost solution in the sense that it can be built on top of any traditional sensor system with minor modifications on the system-level analog-to-digital module. Through the post-layout sensor system we show the experimental images to demonstrate the effectiveness.

Abstract: In this paper, data mining algorithms have been refined and optimized to achieve the intelligent detection of network data. Winsock2 SPI used in the design of interception of network data, and use "session filtering" approach to network packet filtering. System is divided into control rules and intelligent detection module. Through practical testing, the system can display real-time network connection status on the application procedures can be effective control of network data can also be intelligent detection.