Earticle

The internet has become indispensable part of people's life. For enterprises, there are mass of valuable information in the internet. It not only includes competitor information, but also includes customer’s evaluation of products. These information is an important source of business intelligence. This paper aims to build a focused crawler to filter business intelligence from vast amounts of information in the internet. The crawler takes a certain number of web pages as seed. Then extract URLs in these pages, and parse main text of every URL. After that, the crawler calculates relevancy between every main text and the crawler’s topic based on VSM (vector space model) and TF-IDF (Term Frequency-Inverse Document Frequency). If a web page is relevant, it will be saved; otherwise, it will be discarded. At last, an experiment is done to test the performance of crawler. It can be seen that the recall rate and accuracy of the crawler is very high though the result of this experiment.

This study developed a real-time remote monitoring system (RTRMS) to receive the vibration frequency of bridge pier. The system included a front station and a middle station. A multi-hop wireless routing is employed to transmit the data from the front to the middle station. The front station includes a receiver equipped to receive the vibration frequency, and a wireless sensor network to transmit the data. The middle station is designed by an embedded system for storing the data. The pressure test shows that the loss rate of received data is less than 0.6%. The consuming power of one day is 3 ampere hours in the front station and 30 ampere hours in the middle station if the 12 voltage battery is used.

High-performance conjugate gradient (HPCG) is the latest benchmark adopted by the TOP500 organization, and thus how to optimize the HPCG source code for different heterogeneous computing platforms to achieve a higher floating-point computation rate has already become a new hot issue in HPC field. In the paper, we used the CPU + MIC heterogeneous computing platforms, and successfully ported HPCG to the platform. Through the analysis of HPCG source code and optimization for CPU + MIC platforms, practical significance and the value of further research is put forward. Results of performing the benchmark indicate that the design of optimization methods is reasonable and has facilitated the speedup of HPCG benchmark.

Artificial neural network (ANN) have wide applicability in various applications in the life, one of them is apply to recognize characters and numbers, and we know that the Automatic License Plate Recognition (ALPR) is very important in the Intelligent Transportation System (ITS) and it is beginning in research and application in Vietnam. Usually, an ALPR system consists of three parts: 1) license plate location, 2) character segmentation, 3) characters & numbers recognition. In this paper, we proposed an improved method for the characters & numbers recognition part. And then, we apply to recognize characters & numbers of Vietnam License Plates (LP), which combined neural network and image processing technologies. In the training work, we used two networks and back-propagation (BP) algorithm for characters & numbers training with noises, separately, which the computing time and accuracy will be improved. In the using network work, we used the image processing technology for pre-processing to obtain high quality of characters & numbers before put in the trained network to improve accuracy of the system. We tested on 600 Vietnam LP images, which obtained from the actual systems, these images are very different background such as illumination, license angles, size and type, colors, light conditions in Vietnam environment. Our approach is more effective than some of the existing methods and satisfied for all types and color of Vietnam license plates and Vietnam environment.

In East Asia, the high penetration of student cell phones, with built-in features that include bilingual dictionaries, SMS, Email, Internet access and videocams, already offers ubiquitous computing facilities for pedagogical applications. This paper describes an EFL task that required Korean freshmen of Hyejeon College in Chungnam to make L2 English video guides to their campus. Videos were made on their built-in cell phone videocams, and then emailed to their instructor. After file conversion, their videos were uploaded to the instructor’s vblog on his homepage on the English language social networking site US.Cyworld.com (a sister site to the Hangul social networking site Cyworld.com which most Korean students already use). Students were instructed by email to view the videos there, and to then post responses in his homepage guestbook. This required them to use English to set up a personal account and to navigate the social networking site, as well as to compose and post responses. The task illustrates the developing critical importance of L2 Digital Literacy within EFL pedagogy.

A number of multi-phase motors can be series- connected and driven by a single inverter via the appropriate phase transformation rules, and all motors in series can be independently controlled. In this paper, the working principle of symmetrical Six-phase PMSM series connecting three-phase PMSM is proposed, a novel SVPWM method to achieve the decoupled control is presented. The implementing method of SVPWM is presented. In Matlab/simulink, the motor operating conditions，via id=0 vector control strategy, of variable load and speed are analyzed; the feasibility of the proposed SVPWM control strategy is verified.

Due to continuously increasing demand of wireless communication technology, the problem of spectrum shortage arises. Cognitive radio technology enables efficient utilization of the existing wireless spectrum resources. CRN utilizes spectrum band by allowing secondary users to use the spectrum opportunistically, by changing their transmission parameters. We need to analyze the performance of a wireless network. To analyze the performance of a wireless network, game theory is used due to its ability to model individual, independent decision makers. In this paper we model how game theory can be used to allocate power levels to different CR nodes in a CRN at physical layer to ensure a certain QoS.

Aimed at the defects of the traditional Canny operator, this paper puts forward an improved algorithm in edge detection. First, this paper gives a new method on selfadaptive image block based on threshold value. Next, by proposing a new hybrid filterbank of self-adaptive median and morphology, we adopt this hybrid filter-bank to smooth the noise image. Then, we add the information of gradient in two bevel directions, so that the information of gradient is more complete. Last, by using the threshold value to process the image of gradient which is after non-maxima suppression, we obtain the image edge. For the noise image, this improved algorithm not only can filter out noise well, but also the image edge is continuous, smooth, clear. The experimental results show that the improved algorithm has a good effect in edge detection, strong capability of noise immunity. The objective evaluation and visual effect are good, too.

The challenge of modern machining industries is mainly to achieve high quality, in terms of dimensional accuracy, surface finish and high production rate. In the present work, an attempt has been made to explore the effect of EDM process parameters on various Surface Roughness characteristics Ra, Rq and Rz. The experiments have been done on medium carbon steel EN8 which has high applications in tool, oil and gas industries. For the experimentation, Pulse on time (PON), Pulse off time (POFF), Wire tension (WT) and Wire feed rate (WF) were considered as EDM inputs. Similarly, Surface roughness parameters Ra, Rq and Rz were taken as output characteristics. Taguchi’s standard L27 (3 level * 3 parameters) Orthogonal Array was used for conducting the experiments and optimization of multi responses was done by Grey analysis. From the Grey analysis, optimal combination of machining parameters for Surface Roughness characteristics was found at Pulse-on time (PON):131 μs (level 3), Pulse-off time (POFF):58 μs (level 2), Wire tension (WT):2 Kg-f (level 1) and Wire feed rate (WF):4 m/min (level 1). Analysis of variance was used to find the influence of process parameters on responses. From ANOVA of Grey Relational Grade, it is found that wire feed has high influence (F= 59.18) and pulse off time has very low influence (F= 2.50) in effecting the Surface Roughness parameters taken simultaneously. Regression models for the responses were prepared by using MINITAB-16 software. From the residual analysis, it is clear that the models prepared for the responses were more accurate, adequate and they can be used for prediction of surface roughness characteristics. Finally, the experimental and predicted values were compared and they found very close to each other.

The crystallization behavior and microstructural change in glass-ceramics with a cordierite composition were analyzed as a function of concentration and etching time of the HF solution in order to enhance the degree of crystallinity of the glass. Compared to a specimen without etching, the glass frit specimens etched with HF solution showed increased crystalline peak intensities of the μ-cordierite phase in the XRD pattern. The crystal size in the glass matrix also increased with an increasing concentration of the HF solution for the etched glass frit. The crystal peak intensity of the α-cordierite phase in the glass-ceramics made with glass frit etched with 0.5-1.5 wt% HF solution had a slightly higher value than that of pure glass frit regardless of the etching time. The intensity of the specimen with etched glass frit with 3.0 wt% HF solution, however, was lower than that of the specimen of the pure glass frit. Obviously, for the glass-ceramics etched with HF solution of various conditions, the α-cordierite phase is more favorable for crystallization than the α-cordierite phase. This study revealed that the microstructure and ratio of the crystallinity of the α-cordierite phase over the α-cordierite phase in the obtained glass-ceramics could be controlled by changing the HF-etching conditions followed by a heat treatment process.