2015, 4(2):1-6. DOI: 10.12146/j.issn.2095-3135.201502001
Abstract:3TPS/TP parallel robots generally have the characteristics of strong coupling, nonlinearity and multi-variables, which make it difficult to establish a precise mathematical model for the conventional PID(Proportion Integration Differentiation) control algorithm, resulting in a limited application. In this paper, a fuzzy PID control algorithm, which is the combination of the fuzzy control algorithm with the conventional PID control algorithm, was designed and applied to the servo motor in the control system of the 3TPS/TP parallel robot. The simulation results show that the fuzzy PID control algorithm has a better control effect than the conventional PID control algorithm in the control accuracy, stability and adaptability, meeting the expected requirements.
2015, 4(2):7-21. DOI: 10.12146/j.issn.2095-3135.201502002
Abstract:With the proliferation of the diversified applications on heterogeneous media, online contents and offline services have influenced the daily life of web users in a more comprehensive way. In this paper, the concepts and methodologies for heterogeneous media analysis, which aim to obtain physical and social attributes from huge amount of data from heterogeneous sources were introduced, and the intrinsic mechanism for modeling the semantic divergence, complicated correlations and the information propagation was revealed. Firstly, we discussed the heterogeneous media with properties of cross-platform, cross-modality and diversity, and put forward the challenges and opportunities in studying heterogeneous media analytics, and discussed the impact of studying the heterogeneous media. Secondly, we provided literature review from three perspectives, i.e., semantic analysis and understanding, heterogeneous correlation modeling and community modeling. Lastly, we introduced our research works on the semantic modeling, correlation modeling and social behavior modeling on heterogeneous media resources.
2015, 4(2):22-33. DOI: 10.12146/j.issn.2095-3135.201502003
Abstract:With the rapid increase of 3D model on the internet, it is necessary to develop a convenient and reliable content-based 3D shape (model) search engine. Sketch has the ability to express concept as a visual icon, which is in line with the human habit of passing information, and thus becomes an important interactive means in 3D shape retrieval. However, there is often a larger semantic gap between the standard 3D shape representation and the 2D sketch which expresses human consciousness, which brings a lot of technical challenges to the sketch-based shape retrieval. In this paper, the relevant background and technological advances on the sketch-based 3D shape retrieval were introduced, and the latest methods that use context information to fill the semantic gap were particularly focused on.
2015, 4(2):34-38. DOI: 10.12146/j.issn.2095-3135.201502004
Abstract:To investigate the comparability of conventional biochemical assay results between Celercare M1 and Beckman DXC800 analyzer, and provide the basis for clinical laboratory accreditation and mutual recognition of test results in different laboratories, Beckman DXC800 detection system (comparison method) and Celercare M1 detection system (test method) were used respectively to make a determination for conventional biochemical items with fresh serum according to the EP9-A2 document of CLSI. We caculated the system bias of each item between test method and comparison method at the level of medical decision and judged the comparability of test results according to the half of CLIA’88 standard. It is shown that the correlation coefficient and the linear equation between Celercare M1 and Beckman DXC800 analyzer are excellent(R 0.975，P＜0.01), the result biases for each item in medical decision levels are lower than 1/2 CLIA’88 acceptance standard. It is demonstrated that the measurement results between Celercare M1 detection system and Beckman DXC800 detection system have excellent comparability.
2015, 4(2):39-45. DOI: 10.12146/j.issn.2095-3135.201502005
Abstract:In this paper, a novel method for tracking without a marker was proposed. This method alleviated many constraints in augmented reality systems based on fiducial markers. To improve the tracking stability in multi-scale, the effective features and space geometry structure were detected, and the effective features were searched in a multi-scale model. Based on space geometry structure of features, the effective feature points were selected and fictitious features points were wiped off. Experiments show that the proposed algorithm works robustly in the video with scaling objects. The feature points reprojection error of every frame is smaller than one pixel, and the average of feature points reprojection error is kept in sub-pixel.
2015, 4(2):46-49. DOI: 10.12146/j.issn.2095-3135.201502006
Abstract:In pattern recognize and computer vision, circle detection is a critical issue. For the moment, the major concern of most circle detection algorithm is robustness and computational efficiency. Randomzied approaches for circle detection have the advantages of less computational time and less memory requirements. However, randomzied approaches involve in examining a large number of candidate circles and may not suitable in real-time applications. In the paper, the symmetry property of the circle was adopted to select the promising candidates for further investigation. At the same time, not all edge pixels in the image, but the edge pixels between the inscribed square and exo-square were collected when counting the number of pixels on the candidate circle. The experimental results show that the proposed algorithm performs fast while maintaining the accuracy.
2015, 4(2):50-56. DOI: 10.12146/j.issn.2095-3135.201502007
Abstract:It is probable that ghost would be produced when background model is established with pixel-based adaptive segmenter algorithm. According to the theory that adjacent pixel points have similar pixel values in spatial distribution in VIBE algorithm, the difference of foreground pixels was computed which are judged in the first time and the neighborhood pixel. Then the difference and adaptive threshold value were compared through weight to determine whether the pixel is foreground pixel point or ghost which will be judged as background pixel. At last the background models would be updated. Through twice judgments of the foreground pixels, the ghost would be removed quickly. The experiment results show that the improved algorithm removes the ghost faster than the original method.
2015, 4(2):57-65. DOI: 10.12146/j.issn.2095-3135.201502008
Abstract:In this paper, three different growth mechanisms of photovoltaic material CZTSe based on CZTSe phase diagram were analyzed in details: (1) growth pathway based on zinc-rich phase, (2) growth pathway based on Cu2SnSe3-ZnSe reaction and (3) growth pathway based on Cu-rich phase. Then, the optimal reaction pathway was summarized for the growth of CZTSe films. The “4-chamber-8-source co-evaporated system” which was developed by SIAT was introduced to deposit the CZTSe films in this paper, and the system monitored the phase change during the growth of CZTSe successfully and different phase change processes corresponded with different temperature change pattern. These conclusions would be a significant guidance in future work.
2015, 4(2):66-74. DOI: 10.12146/j.issn.2095-3135.201502009
Abstract:Cognitive radio networks achieve spectrum sharing by utilizing the idle periods of licensed bands via dynamic spectrum access technique. Spectrum characterization and prediction help perform more efficient spectrum sensing and then optimize spectrum access strategy. In the paper, UTD-HDP, a nonparametric Bayesian model, was introduced by extending the standard HDP(Hierarchical Dirichlet Process) to perform utilization data clustering and distribution parameters estimation. Using this model, we characterized the features of spectrum utilization adaptively and predicted the future spectrum utilization with high accuracy.
2015, 4(2):75-85. DOI: 10.12146/j.issn.2095-3135.201502010
Abstract:The blood oxygen saturation is a very important physiological index in common clinical diagnosis and family care. The patient’s life is related to the level of blood oxygen saturation to some extent, so the oxygen saturation should be detected in the clinical, especially in the operation. Because monitoring the volatility of the blood oxygen saturation plays an important role in the prevention and treatment of the pulmonary heart disease, it has the extremely vital significance. The SpO2 system which we designed is based on AFE4400 and we developed an application of android smartphone in order to display the PPG signal and the blood oxygen saturation timely and exactly. It’s easy to use and makes a further cost reductions. The experimental results show that the system has a very high accuracy.
2015, 4(2):86-92. DOI: 10.12146/j.issn.2095-3135.201502011
Abstract:In this paper, a simplified magnetic localization method and system for indoor robot was proposed. A transmitter coil and a set of three axis receiver coils were ranged in the localization space to form the magnetic coupling system. The Cartesian coordinate system was built according to the three-axis orthogonal receiving coils. A magnetic field was setup by the transmitter coil which was activated by a sinusoidal current signal. The 3-axis receiver coils sensed the change of the magnetic signal around, and their intensities could be calculated to extract the characteristic parameters for computing the position of the transmitter coil. Here, the transmitting coil was fixed on the mobile robot, while the 3-axis receiver coil was located in a certain position of the building. The characteristic parameters could be calculated based on the magnetic dipole model. According to the simulation and experimental results, this method proves to have high efficiency and satisfactory accuracy which are suitable for mobile robot localization.