Current Issue : October - December Volume : 2019 Issue Number : 4 Articles : 5 Articles
The geometric error motions of rotary stages greatly affect the accuracy of constructed\nmachines such as machine tools, measuring instruments, and robots. In this paper, an embedded\nsensor system for real-time measurement of two radial and three angular error motions of a rotary\nstage is proposed, which makes use of a rotary encoder with multiple scanning heads to measure\nthe rotational angle and two radial error motions and a miniature autocollimator to measure two tilt\nangular errors of the axis of rotation. The assembly errors of the grid disc of the encoder and the\nmirror for autocollimator are also evaluated and compensated. The developed measuring device can\nbe fixed inside the rotary stage. In the experiments, radial error motions of two points on the axis\n(h= 5 mm and 60 mm) were measured and calibrated with LVDTs, and the data showed that the\nradial error motions of the axis were less than 20 micro m, and the calibration residual errors were less\nthan 2 micro m. When intermittent external forces were applied to the stage, the change of the stageâ??s\nerror motion could also be monitored accurately....
Relay technology application becomes prevalent nowadays, as it can effectively extend\nthe communication distance, especially for vehicular networks with a limited communication range.\nCombined with vehicular cloud (VC), transmission efficiency can be improved by offloading partial\ndata. Hence, designing a vehicle relay algorithm and implementation embedded vehicle device is\ncritical. In this paper, VC is considered to deal with the complexity computation in our proposed\nsystem model. Without a loss of generality, an end-to-end vehicle communication with one assisted\nvehicle is analyzed firstly on a transmission link based on VC. Here, the signal-to-noise ratio\n(SNR) on the receiving end and link outage probability is obtained to enhance the link reliability.\nThe VC computing helps us further simplify computational complexity. Subsequently, an embedded\nvehicle-enabled device is designed to achieve the optimal path relay selection in realistic vehicular\nenvironments. In the functional device framework, we display an optimal path relay selection\nalgorithm according to the link quality. Finally, the performance of the transmission link on the\noutage probability related with SNR is verified in the simulation results. Meanwhile, the effect of the\nrelay gain is also analyzed. The application of a vehicle-enabled embedded device could improve the\nperformance of vehicular networks....
In this paper, the development of a smart scalable system for liquid supply based on highprecision\nperistaltic pumps is described. The architecture of software and hardware for the\nproposed system is considered. This liquid supply system can be used for mixed and layered\ncocktail preparation in public catering establishments, such as bars, as well as for home use. Due to\nthe flexibility and scalability of the system, it is possible to apply it in various branches of human\nactivity, where fine dosing of liquids is required, e.g., for beverage mixing, cooking, health and\nmedical applications. By using open architecture and software, this system can be built in a smart\nhome environment. The cross-platform control software and an embedded Bluetooth module allow\nusing the developed setup in various use case scenarios. The result of the project is a DIY-kit, capable\nof mixing 6 to 32 different liquids in specified proportions and the programmable sequence....
The traditional human comfort meter has the following defects: the interface\nis not uniform; the operation is cumbersome and complicated; the interface is\nunfriendly, and the stability and adaptability are poor. This paper presents a\ndesign scheme for human comfort instrument based on embedded system,\nusing S3C2440 embedded development board and the sensors to collect the\nreal-time temperature, relative humidity and wind speed data and to process\nthe collecting data; then obtaining the human body comfort value according\nto the basic algorithm of human body comfort instrument; giving the human\ncomfort conclusion according to the diastolic index range of human comfort,\nand showing the temperature and humidity, wind speed, comfort value and\nconclusion through writing the Qt graphical user interface program. At the\nsame time, the human comfort instrument has the data storage function. The\nhuman comfort instrument is high in integration, strong in real time, high in\nsensitivity, stable and reliable, and it meets the development goals of the intelligent\nmeteorological service, and meets the demand of the meteorological\nservice that is closer to life, and it has broad development prospect....
In this work, a method was developed to determine the concentration of Eu3+ and Tb3+\nions in a thin-film sample of SiO2, co-doped with ZnO-nanocrystals (ZnO-nc), to produce a sample of\nany desired colour in the International Commission on Illumination (CIE) colour space. Using this\nmethod, a white light emitting sample was fabricated. The thin-film sample combines red, green and\nblue emissions from the Eu3+ ions, Tb3+ ions and ZnO-nc, respectively, to create white light or light of\nany desired colour. The emissions at 614 nm and 545 nm from Eu3+ and Tb3+ ions, respectively, is due\nto the energy transfer from the excited ZnO-nc to the rare-earth (RE) ions. In this way, only a single\nexcitation wavelength is needed to excite the ZnO-nc, Eu3+ and Tb3+ ions in the sample to produce\nemission of a desired colour from the sample. We developed an empirical 4th-degree polynomial\nequation to determine the concentrations of Eu3+ and Tb3+ ions to produce light of any desired colour\nin the CIE colour space. Based on the above empirical equation, the concentration of Eu3+ and Tb3+\nions for a white light emitting sample was found to be 0.012 and 0.024 molar fractions, respectively.\nThe white light emission from the sample was confirmed by fabricating the sample using the low-cost\nsolâ??gel process. The stimulated emission spectra and the experimental emission spectra of the white\nlight sample fit very well. The results presented in this work are important to develop energy efficient\nsolid state lighting devices....
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