At present, the AC servo system which uses the PMSM as the control object is widely used in such areas as the CNC machine tools, industrial robots and space. No sensor-based servo system is becoming the development tr...
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At present, the AC servo system which uses the PMSM as the control object is widely used in such areas as the CNC machine tools, industrial robots and space. No sensor-based servo system is becoming the development trend of high-performance permanent magnet synchronous motor control system. The paper introduced a design of sensorless PMSM (permanent magnet synchronous motor) control system based on TMS320F2812. The performance characteristic of TMS320F2812 was expatiated, and itpsilas function in the sensorless PMSM control system was given in the paper. We discussed the composition of hardware and the design of software. The system used of the intelligent control strategies such as SVPWM (space vector pulse width modulation) and SMO (sliding mode observer), and made full use of the DSPpsilas high-speed computing power and abundance of on-chip resources, to achieve system real-time control, make the system having a good dynamic quality and steady performance. The processor is suitable in the field of motor control in the extreme, and has a wide range of practical value.
Streamline is one of the basic techniques for flow ***,constructing a streamline includes three main sub-procedures:point location,numerical integration and vector field interpolation,In this paper,by dividing the CFD...
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Streamline is one of the basic techniques for flow ***,constructing a streamline includes three main sub-procedures:point location,numerical integration and vector field interpolation,In this paper,by dividing the CFD computational grids which are curvilinear grids into tetrahedrons and set the topological relationship among the tetrahedrons,"compass" algorithm based on the normal vector of tetrahedron is used to fasten point location *** method presented in this paper can generate streamlines in physical space directly and thus improve the efficiency and precision of streamline constructing.
Feistel and SPN are the two main structures in designing a block cipher algorithm. Unlike Feistel, an SPN has an asymmetric structure in encryption and decryption. In this paper we propose an SPN algorithm which has a...
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Feistel and SPN are the two main structures in designing a block cipher algorithm. Unlike Feistel, an SPN has an asymmetric structure in encryption and decryption. In this paper we propose an SPN algorithm which has a symmetric structure in encryption and decryption. The whole operations in our SPN algorithm are composed of the even numbers of N rounds where the first half of them, 1 to N/2, applies function and the last half of them, (N+1)/2 to N, employs inverse function. Symmetry layer is executed to create a symmetry block in between function layer and inverse function layer. AES encryption and decryption algorithm, whose safety is already proved, are exploited for function and inverse function, respectively. Proposed symmetry layer is the simple logical operation, because this doesn't effect at the whole process time of encryption and decryption. The proposed algorithm can be easily applied to the algorithm which has different encryption and decryption and make it same, and it can be good idea to be used to design a new block cipher algorithm.
Web 2.0 is the latest development of Internet technology,it is being used into more and more *** paper explains the concepts and features of web 2.0,combines web 2.0 with network education,proposes an overall design m...
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Web 2.0 is the latest development of Internet technology,it is being used into more and more *** paper explains the concepts and features of web 2.0,combines web 2.0 with network education,proposes an overall design model of network education supporting system based on web 2.0,analyses the main function module and discusses the technology achievement of main function *** system adds many teaching functions different from traditional network education supporting systems,such as blog,RSS,*** network education supporting system based on web 2.0 enhances learner's positivity of active studying and improves the network education's quality.
For unable to establish geometrical relationship of coordinates, conventional methods of 3D shape recovery can not be adopted to a great number of precious historical images to recover the 3D shape of the objects and ...
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For unable to establish geometrical relationship of coordinates, conventional methods of 3D shape recovery can not be adopted to a great number of precious historical images to recover the 3D shape of the objects and environments in the images. The new method of 3D shape recovery based on single frame historical image is proposed in this paper. The core idea of this research is that, according to the change of the shade of gray of each pixel, the tilt angle and slant angle of the surface vertical vector of each object's pixel in the image is analyzed, then the depth of each pixel is calculated in response to the tilt angle and slant angle. Simulating human being s vision system and the process of thinking of brain, this method makes the process of man's 3D comprehension of single image computerize to obtain 3D digitized data. These 3D digitized data can be used in the fields of the 3D recovery of historical relics and the identification of 3D portrait and stereo literal.
In modern information society, a high volume of important information is communicated in an on-line network. Specially, mobile environments that handle radio communication are more flexible than wired communication, a...
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In modern information society, a high volume of important information is communicated in an on-line network. Specially, mobile environments that handle radio communication are more flexible than wired communication, and are developing rapidly. With the development of mobile environments, sensitive information can be compromised on-line, and demand for security has increased. Therefore TCG (trusted computing group) that is the standardization group for trust computing, suggested MTM (mobile trusted module) that is a hardware-based security module for security in mobile environments. MTM protects user privacy and platform integrity, because it is embedded in the platform, and it is physically secure. However, a security approach is required when secret data is migrated elsewhere, because MTM provides strong security functions. In this paper, we analyze the TCG standard and migration method for secure data, then we propose a secure maintenance scheme for secret data using USIM(universal subscriber identity module) that is a user authentication module.
With the development of Internet-based computing, we can no longer trust them to sustain the applications we depend on because IT infrastructure technologies fail to keep pace with emerging threats. Direct Anonymous A...
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With the development of Internet-based computing, we can no longer trust them to sustain the applications we depend on because IT infrastructure technologies fail to keep pace with emerging threats. Direct Anonymous Attestation (DAA) enables remote authentication of a user while preserving privacy under the user's control. The existing protocols for direct anonymous attestation of Trusted Platform Module (TPM) with limited storage space and communication capability could not satisfy the higher requirements of performance and security. From bilinear pairings, this paper proposes an optimized DAA protocol. The analysis result of the proposed protocol shows that cost of TPM remains lower than the BCL-DAA scheme and the computational cost of host and verifier are highly reduced. Furthermore, the proposed scheme is secure in the random oracle model under the l-MOMSDH assumption.
This paper researched the development and application regarding the black pottery’s rapid *** Tibetan nationality’s Nixi black pottery is the nationality’s traditional handcraft that possess
This paper researched the development and application regarding the black pottery’s rapid *** Tibetan nationality’s Nixi black pottery is the nationality’s traditional handcraft that possess
This paper aims at responding to the questions in the traditional cultural heritage protection and exploring new visual representation forms and human-computer natural interaction design methods to carry forward the D...
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This paper aims at responding to the questions in the traditional cultural heritage protection and exploring new visual representation forms and human-computer natural interaction design methods to carry forward the Digital Cultural Heritage(DCH)*** paper combined interaction design with Chinese traditional shadow puppet art to create a new media artwork based on computer image capturing technology,in order to actively reveal the relationship of the inner construction factors about culture context and outside restriction factors about Cultural Heritage Zeitgeist and achieve the culture systematic preservation,heritage sustainable development and civilization effective *** paper provides interaction design principles and guidelines.
Case retrieval is an important part of case-based reasoning *** to the idea of Ant Colony Algorithm,the paper performs clustering to case base,and on this basis,in accordance with the idea of k-means algorithm,designs...
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Case retrieval is an important part of case-based reasoning *** to the idea of Ant Colony Algorithm,the paper performs clustering to case base,and on this basis,in accordance with the idea of k-means algorithm,designs a case retrieval *** the paper analyzes the organization method based on heterogeneous case,focuses on the clustering algorithm of case and the retrieval algorithm of *** experimental results show that the method is able to convert the maintenance of case base into the maintenance of sample case,thus effectively improve the efficiency of case retrieval.
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