Advanced Materials Research Vols. 791-793

Abstract: The performance of computer hardware and software has been improved, so computer 3D virtual simulation is gradually applied in all walks of life. It needs to handle large amounts of data in computer 3D simulation process. In the data storage and calculation process, it must choose efficient algorithms to solve the problem of redundancy data. Based on this, the paper respectively applies the BHIK algorithm and CCD algorithm, the two algorithms to the simulation of computer 3D motion recognition process, and it has compared the efficiency of the two algorithms. By the comparing, the calculation speed of BHIK algorithm and convergence are significantly better than the CCD algorithm. The execution time of BHIK algorithm is only 1/10 of CCD algorithm, and the convergence speed is 4 times of CCD algorithm. So we choose BHIK algorithm as the computer 3D simulation algorithm. Finally, it takes the football teaching system as an example to verify the validity and reliability of the algorithm.

Abstract: With the development of computer technology, art designs are more and more rely on graphic image processing and three-dimensional modeling, especially in landscape designs. How to use assisted image analysis system scientifically is one of hot research topics in the field currently. This article first analyzes the meaning of integration of landscape architecture and landscape painting theory. According to this, it analyzes the application and principle of image analysis auxiliary systems of the integration of landscape architecture and landscape painting theory through the case. It further analyzes the development prospect of image analysis support system and puts forward constructive comment which provides a scientific basic for the researches in this field on some extent.

Abstract: For complex application layer protocol of low altitude communication system which may be implemented with several wireless communication technologies which include BeiDou Navigation Satellite System, 3G, Digital radio, GPS, ADS-B, etc., we design a low altitude communication protocol conversion process based on pattern match to enhance the capacity of low-altitude flight service stations processing multi-source information from low-altitude aircrafts or other stations. In the process, the application layer protocol of information is identified with the algorithm based on BM pattern matching and CAM multi-pattern matching fusion firstly, secondly, the common intermediate protocol information is produced, and target protocol information is generated finally.

Abstract: We need to achieve real-time parameter control and process a large number of complex numerical calculations in the research of satellite mobile communications fading channel. MATLAB has powerful numerical calculation functions and graphing display characteristics, VC++ has powerful functions to make program interface and can achieve port operation, real-time processing. MATLAB and VC++ mixed programming combines the advantages of both languages and provides strong technical support to the research of satellite mobile communications fading channel. This paper introduces the calculation model of satellite mobile communications fading channel and presents the process of mixed programming. The complex calculation of fading channel is completed and the results are presented.

Abstract: Location Entity Recognition (LER) is an important part in Named Entity Recognition (NER), and it is a significant research topic in this domain to use the abundant unlabeled corpus to improve recognition performance. A new method combined Active Learning with Self-Training is proposed, which selects samples based on confidence and 2-Gram frequency, and expands the training set by annotating the unlabeled corpus manually and automatically. The experiments reveal that the F-measure of this method is 8% higher than randomized Active Learning while the annotation is only 1/3 of the latter. And using this method, only 5% of characters in the extended training set need to be labeled to acquire a similar performance with complete manual annotation.

Abstract: Direct connection and reflective connection are commonly used in traditional Trojans communication model, which have some significant deficiencies in hiding, anti-tracking, and efficiency. To improve the aspects above in traditional Trojan horse communication model, the author proposed a hybrid communication model based on P2P technology. The model uses P2P intranet penetration protocol to build the channel between the controlled station and the control station, and uses P2P node servers for saving the Trojans status and transferring some data between the controlled and the control. The topology of networks for controller will be very flexible. Using the IP traceback technology will be difficult to track the controllers. Using UDP protocol in the hybrid communication model for data transmission will hide the network status. Control sites can work in distributed mode. By using the model, the hiding-ability, anti-traceability and communication efficiency will be greatly improved.

Abstract: In a long time, the specialists in underwater acoustic countermeasure field were used to get an approximate evaluation of the transmission loss of noise signals by spreading loss equation of spherical wave, which led to results with a low accurateness. Based on normal mode theories and discrete Fourier transformation (DFT), derived the composition and process of the broadband acoustic propagation model. Then the transmission loss could be calculated via this propagation model, which could get a relatively more accurate result. The influence of three key positional parameters, the orientation, distance and depth of the noise-jammer were studied in this paper. The method and conclusions in this paper can provide a reliable foundation for tactical research on noise-jammers.

Abstract: As the role of medical imaging in clinical diagnoses and treatment has been more and more important, CT scan has been applied more widely. How to extract abdominal artery from CT image automatically and accurately has a significant value for abdominal artery disease. Because the medical image is of complexity and diversity, traditional segmentation method cannot complete the segmentation task very well. Therefore, this paper presents a method for extracting abdominal artery from CT images using three-dimensional region growing algorithm combined with image morphology. The experimental results show that the proposed method is an effective way for improving the accuracy of abdominal artery segmentation.

Abstract: Objectives The aim of this study was to compare 3D accuracy of tooth image reconstruction from three kinds of CT scans using 3D superimpositional method. Methods 18 sound extracted human teeth were scanned by 3D optical system, spiral CT, micro-CT, and cone-beam CT scanner. The digital teeth images reconstructed from three kinds of CT scans were superimposed onto the standard image from optical scans respectively. Distribution patterns of shape discrepancy were presented using histogram, as well as showed in different colors on the superimposed imagines. The ratio of voluminal discrepancy versus the volume of the standard image (R_VD/VS) was calculated and analyzed, using the matched-pair t-test and rank sum test. Results Compared with the standard tooth image, the average R_VD/VS of digital teeth images by the micro-CT, cone-beam CT, spiral CT scans were 5.11%, 20.73%, 24.60% respectively, and there were statistically significant difference among the three kinds of CT scans (P<0.01). Significant difference were also found among the anterior teeth, bicuspids, and molars (P<0.01). Histogram gave the description about the counts and magnitude of the discrepancies. Marked by difference colors, the superimposed images could give visualized information about the magnitude and distribution patterns of discrepancies. Conclusions The digital teeth models reconstructed from the spiral CT, micro-CT, cone-beam CT images are inhomogeneous enlarged, compared with the original models. As the only realizable way to individualized FEM analysis, tooth modeling by CT scans needs more efforts and refinements to improve its accuracy.

Abstract: This paper analyzes the transmission loss of streaming media and presents a adaptive algorithm which can Intelligently adjust itself to the size of the network packet stream when network resources are adequate for the situation,. The algorithm calculates the best data packet based on RTCP protocol by controlling the change of the server-side data packet size to dynamically adjust the sending rate, so that it can achieve the best multimedia data streams transmission in a limited time and under limited network resources to improve QoS of stream media of network.