Current Issue : January - March Volume : 2015 Issue Number : 1 Articles : 7 Articles
To improve the reliability of InSb IRFPAs, underfill has usually been filled between InSb chip and Si ROIC. Around the glass\ntransition temperature, underfill shows viscoelasticity, yet, far below it, which shows apparently temperature dependent mechanical\nproperties. Basing on the temperature dependent elastic model of underfill, firstly a small format array of 8 Ã?â?? 8 elements InSb\nIRFPAs is investigated by changing indium bump diameters and heights; simulated results show that the maximum stress in InSb\nchip has nothing to do with underfill height and is dependent on indium bump diameter; the varying tendency is just like the\nhorizontally extended letter U. When indium bump diameter is set to 24 ????m with height 21 ????m, the maximal stress in InSb chip\nreaches minimum. To learn the stress in 64 Ã?â?? 64 elements in short time, with the above optimal structure, InSb IRFPAs array scale\nis doubled once again from 8 Ã?â?? 8 to 64 Ã?â?? 64 elements. Simulation results show that the stress maximum in InSb chip is strongly\ndetermined by arrays format and increases with array scale; yet, the stress maximum in Si ROIC almost keeps constant and is\nindependent on array sizes; besides, the largest stress locates in InSb chip, and the stress distribution in InSb chip is uniform....
The contactless inductive flow tomography (CIFT) aims at reconstructing the velocity field of electrically conducting fluids, with\nspecial focus on applications in metallurgy and crystal growth technologies. The method relies on the induction of secondary\nmagnetic fields if the moving fluid is exposed to a primary magnetic field. The theoretical foundation of the method is delineated,\nand some early experiments on the reconstruction of the three-dimensional flow in a cylinder are sketched. Then, the recent efforts\nto apply CIFT to various model problems in connection with the continuous casting of steel are summarized...
The legislation of food industry is becoming increasingly strict with regard to the quality of food products. Therefore, the market\nis demanding for automatic systems of analysis that allow fast and accurate monitoring of the evolution of quality parameters in\nagrofood products or permit obtaining information to optimize production processes. In this context, sensors and more specifically\nmicrosensors play an important role since they allow fast and reproducible measurement of a large number of quality parameters\nwith good reliability and can be implemented in portable systems. This paper presents a review of the results obtained with an\nelectronic tongue based on different kinds of microsensors applied to wine analysis by the team of IMB-CNM. This multisensor\nsystem allows on one hand classifying the wine according to its features like grape variety, geographic origin, year, and organoleptic\ncharacteristics and on the other hand quantifying some parameters of interest in quality control, such as alcoholic degree, pH, ions,\ntotal acidity, glycerol, and color....
Accurate and robust positioning technology is expected to promote management level and service efficiency in various industrial\napplications.The strap-down inertial navigation system (SINS) approach has short-termaccurate positioning performance, but the\nSINS is known for its accumulative error over time. Meanwhile, wireless sensor networks (WSN) approach can keep the mobile\ntarget on effective tracking after a long time monitoring, but the WSN may have large positioning error in certain areas. In order to\nmake the positioning method allow profit from their advantages, this paper proposes a positioning technology using SINS approach\nin conjunction with WSN approach. The measurement parameters by SINS and WSN approaches are used. Then the SINS, anchor\nnodes, mobile tags, XBee, and computer are applied to design the positioning system. The estimation results indicate that the\nproposed method can make up for the shortcomings by pure SINS or WSN method and can be available for some accurate and\nrobust applications....
Optical parameters of materials are used for implementing cinematic rendering in the field of graphics. Critical elements for\nextracting these optical characteristics are the accuracy of the extracted parameters and the required time for extraction. In this\npaper, a novel method for improving these elements as well as a comparison to the existing methodology is presented. By using a\nspectrophotometer and custom designed optical imaging equipment (OIE), our method made it possible to enhance accuracy and\naccelerate computing speed by reducing the number of unknowns in the fitting equations. Further, we validated the superiority of\nthe extracted optical characteristic parameters with a rendering simulation....
In permanent magnet synchronous motor (PMSM) traditional vector control system, PI regulator is used in the speed loop, but it\nhas some defects. An improved method of PMSM vector control is proposed in the paper.The active-disturbance rejection control\n(ADRC) speed regulator is designed with the input signals of given speed and real speed and the output of given stator current q\ncoordinate component. Then, in order to optimize ADRC controller, the least squares support vector machines (LSSVM) optimal\nregression model is derived and successfully embedded in the ADRC controller.ADRCobservation precision and dynamic response\nof the system are improved.The load disturbance effect on the system is reduced to a large extent.Thesystem anti-interference ability\nis further improved. Finally, the current sensor CSNE151-100 is selected to sample PMSMstator currents. The voltage sensor JLBV1\nis used to sample the stator voltage.The rotor speed of PMSMismeasured by mechanical speed sensor, the type of which is BENTLY\n330500. Experimental platform is constructed to verify the effectiveness of the proposed method....
Data association is one of the key problems in the SLAM community. Several data association failures may cause the SLAMresults\nto be divergent. Data association performance in SLAM is affected by both data association methods and sensor information. Two\nmeasures of handling sensor information are introduced herein to enhance data association performance in SLAM. For the first\nmeasure, truncating strategy of limited features, instead of all matched features, is used for observation update.These features are\nselected according to an information variable. This truncating strategy is used to lower the effect of false matched features. For\nthe other measure, a special rejecting mechanism is designed to reject suspected observations. When the predicted robot pose\nis obviously different from the updated robot pose, all observed sensor information at this moment is discarded. The rejecting\nmechanism aims at eliminating accidental sensor information. Experimental results indicate that the introduced measures perform\nwell in improving the stability of data association in SLAM. These measures are of extraordinary value for real SLAMapplications...
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