2014, 3(5):1-9. DOI: 10.12146/j.issn.2095-3135.201405001
Abstract:The development of nano-optoelectronic devices is especially relevant to the control of the spatial arrangement of photoactive materials with nanoscale precision. Because of its base pairing and double-helix structure, as well as easy preparation, programmable control over their shape and size, and precise spatial addressability, DNA has been used as the template to organize a variety of nanoscale elements for nanophotonics and nanomedical research. The DNA-based photonic arrays are multiple fluorophores programmed sequentially along DNA scaffold to achieve energy transfer through multi-step fluorescence resonance energy transfer. In this review, the discussion focused on the progrsses of DNA-based assembly photonic arrays in recent years, and insights for future directions were provided.
2014, 3(5):10-18. DOI: 10.12146/j.issn.2095-3135.201405002
Abstract:With the development of medical imaging, its processing and analysis techniques becomes more and more advanced and mature. However, the segmentation of medical image is still a great challenge. In this paper, the recent progress of medical imaging and the characteristics of the recent medical image segmentation techniques were discussed: emphasis on the effective integration of multiple segmentation algorithms. Active shape model (ASM), graph cut (GC) and iterative graph-cut active shape model (IGCASM) methods were used as examples to further illustrate the characteristics of medical image segmentation.
2014, 3(5):19-27. DOI: 10.12146/j.issn.2095-3135.201405003
Abstract:As an advanced biosensing strategy, the electrochemical biosensor is made up of the active sensing biomaterial and the electrochemical signal transducer, and is being widely applied in the fields of clinical medicine, drug and food analysis as well as the environmental monitoring. The electrochemical biosensor has the advantages of excellent specificity, high sensitivity and simplicity. This review focused on the fundamental principle of electrochemical biosensor, its classification and the biomedical applications. The prospect of the electrochemical biosensors was outlined as well.
2014, 3(5):28-36. DOI: 10.12146/j.issn.2095-3135.201405004
Abstract:A new algorithm for 3D mesh simplification based on minimum surface area error was presented in this paper. The algorithm simplifies 3D models by minimizing an error objective function. Firstly, the algorithm used the edge traversal algorithm for calculating the minimum area of each edge. Then the vertex coordinates of those new points were determined by finding the minimum surface area error. The results of our experiment show that our algorithm can not only reflect the local surface geometry changes, but also keep the model in a relatively high fidelity. Experimental results for the effectiveness of the algorithm were also presented.
2014, 3(5):37-44. DOI: 10.12146/j.issn.2095-3135.201405005
Abstract:The traditional Extended Kalman Filter (EKF) will lead to large errors of estimation data and robustness weakening of the identification system when applied to brushless DC motor (BLDCM) to estimate rotor position and speed simultaneously. In this paper, based on the discrete mathematical model of BLDCM and M-estimation, an improved EKF(MEKF) was proposed. Firstly, based on the commutation principle of the BLDCM operation and EKF model, a separate commutation model was built up, which was independent to the EKF. Secondly, in order to identify the rotor speed and position with more precision and to enhance the robustness of system, the observation matrix was modified by M-estimation, and a decoupling technology of speed and position was adopted in the system correspondingly. Thirdly, based on the decoupled time series model of the motor, a rotor position detection model was designed out, so that a precision rotor position can be realized in practice without deep filtration which will lead to great lagging. The experiment and simulationresults show that this method can effectively abate the errors disturbance of the EKF, and it also significantly enhances the anti-interference of the initial value and robustness.
2014, 3(5):45-51. DOI: 10.12146/j.issn.2095-3135.201405006
Abstract:Morphological parameter measurement of Pseudosciaena Crocea plays an important role in its genetic selection and quality improvement. In this paper, an automatic detecting system which can measure the Pseudosciaena Crocea morphological parameters such as weight, length and body width was developed based on the machine vision and weighing sensor technology. The system can automatically detect the external morphology parameters by the machine vision, and get weight parameters through the weighing sensor. The mean errors of dimensional measurement and weighting are 0.28% and 0.74% respectively, which shows that the developed system can completely meet the requirements of morphological parameter measurement for Pseudosciaena Crocea. It is a new effective method to the automatic detection of fish morphology parameters.
2014, 3(5):52-60. DOI: 10.12146/j.issn.2095-3135.201405007
Abstract:The technology of the capsule endoscope for the detection of the gastrointestinal disease has made a major breakthrough. But the clinical feedback show that some problems are to be solved, including the problem of the location and tracking. Among the possible localization technologies, the magnetic positioning technology with advantages of no need for power and not much space occupation and so on, is very suitable to be applied to the problem of localization of the capsule endoscope. In this paper, for the positioning model of the magnetic dipole based on the magnetic positioning technology, a new algorithm —— hybrid artificial bee colony algorithm was proposed and compared with the artificial bee colony (ABC) algorithm and the nonlinear optimization algorithms that the random complex algorithm and the levenberg - marquart (LM) algorithm. The experimental results show that in terms of the positioning accuracy, the stability and the anti-noise ability, the hybrid artificial bee colony algorithm has better performance than the other three methods.
2014, 3(5):61-68. DOI: 10.12146/j.issn.2095-3135.201405008
Abstract:Based on its region-of-interest (ROI) reconstruction advantage, backprojection-filter algorithm has been used in cone-beam CT recently. However, because of its complexity and computation, there is memory insufficiency in the implementation of GPU acceleration. Hence, CUDA-based parallel implementation for BPF algorithm was proposed. Meanwhile, an accelerated projection scheme and other accelerated techniques were included as well, such as features of BPF for acceleration. Besides, video memory pool was introduced to optimize the implementation. With an efficient structure, the simulation results show that it takes only 8.055 seconds by using the new structure to reconstruct 512×512×512 data and only 4.566 seconds for the ROI reconstruction. The output of first block data takes only 1.523 seconds. With a great decrease of memory occupation from 2.5 GB to less than 100 MB, the new scheme is suitable for big data reconstruction.
2014, 3(5):69-75. DOI: 10.12146/j.issn.2095-3135.201405009
Abstract:A hierarchical WSN (wireless sensor network) remote monitoring system was designed to solve the problems of big investment, high costs, and highly difficult sensor wiring when collecting signal notes were increased for wire communication, particularly in some remote regions where the wire communication cannot be used. However, the sensor nodes of the WSN system have the characteristics of random layout expansion and combination. A greenhouse experiment system was established by applying the routing protocol of the wireless network and energy monitoring technique of the WSN system. Based on the experiments and testing performances of the system, the results show that the system is stable and reliable.
2014, 3(5):76-84. DOI: 10.12146/j.issn.2095-3135.201405010
Abstract:Due to the non-planarity of topological graphs for three-phase inverters, it is hard to construct three-phase current-source inverter (CSI) topologies from three-phase voltage-source inverter (VSI) topologies by using dual transformation. In order to form the multilevel CSI topology by making full use of the research findings of the three-phase multilevel VSI, two planar methods of treating with topological graphs of three-phase two-level voltage-source inverter topologies were discussed, and the feasibilities to construct three-phase multilevel CSI topologies by applying such methods were analyzed. By adding an extra voltage-source to the three-phase flying-capacitor multilevel VSI, an equivalent circuit topology with planarity was obtained, and a new kind of three-phase multilevel CSI topology was proposed through the dual transformation in this paper. Lastly, the multi-carrier sinusoidal pulse width modulation (SPWM) technique was adopted to verify the correctness and rationality of such multilevel CSI topology by simulation.
2014, 3(5):85-96. DOI: 10.12146/j.issn.2095-3135.201405011
Abstract:The magnetic sensor array Honeywell HMC1043 was used to collect the magnetic information of the permanent magnet. Because the precision of the system is directly affected by sensor parameters including the position, the direction and the sensitivity coefficient of the sensor array, the accurate calibration of the magnetic sensors was indispensable to obtain the accurate sensor parameters of the sensor array in the magnetic tracking system. A method of objective error function and optimization calculation for the problem of magnetic sensors calibration was proposed in this paper. The error function was minimized through updated parameters and iterative calculation. Then the accurate location, direction and sensitivity coefficient of the sensors array were obtained. This method was applied to the actual sensor system. In MATLAB environment, the position, the direction and the sensitivity coefficient of the sensor array were determined through calculation and the magnetic information of the permanent magnet was collected by the computer to realize calibration. By this method, the accuracy of the system localization was improved significantly, which therefore verified the feasibility and rationality of the algorithm.
2014, 3(5):97-103. DOI: 10.12146/j.issn.2095-3135.201405012
Abstract:The video monitoring system is the latest development trend of the digital age, and the remote video transmission is the main research content. In this paper we take the industrial field as the research background, with C# as its development environment, sending video information collected by Haikang camera to the remote server database by Socket, so the remote personnel or personnels can get the video data on a remote server through WCF, achieving the function of remote video transmission and real-time video display. And the host computer to establish a Socket again for XML to transmit flag with the remote client.