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Number of results: 6
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Abstract

The development of accurate computer control of a 3 MV Van de Graaff accelerator operation is described. The developed system comprises the accelerator turn-on and turn-off procedures during a normal run, which includes the setting of the terminal voltage, ion source light up, beam focusing and control of ion beam current and energy during operation. In addition, the computer monitors the vacuum and is able to make a detail register of the most important events during a normal run. The computer control system uses a LabVIEW application for interaction with the operator and an I/O board that interfaces the computer and the accelerator system. For everyday operating conditions the control implemented is able to turn-on and off the machine in about the same time as a specialized technician. In addition, today more users can make experiments in the accelerator without the help of a specialized operator, which in turns increases the number of hours during which the accelerator can be used.

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Authors and Affiliations

José Lopes
Francisco Alegria
Luís Redondo
Jorge Rocha
Eduardo Alves
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Abstract

With improved technological successions, wireless communication applications have been incessantly evolving. Owing to the challenges posed by the multipath wireless channel, radio design prototypes have become elemental in all wireless systems before deployment. Further, different signal processing requirements of the applications, demand a highly versatile and reconfigurable radio such as Software Defined Radio (SDR) as a crucial device in the design phase. In this paper, two such SDR modules are used to develop an Orthogonal Frequency Division Multiplexing (OFDM) wireless link, the technology triumphant ever since 4G. In particular, a non-coherent end-to-end OFDM wireless link is developed in the Ultra High Frequency (UHF) band at a carrier frequency of 470 MHz. The transmitter includes Barker sequences as frame headers and pilot symbols for channel estimation. At the receiver, pulse alignment using Max energy method, frame synchronization using sliding correlator approach and carrier offset correction using Moose algorithm are incorporated. In addition, wireless channel is estimated using Least Square (LS) based pilot aided channel estimation approach with denoising threshold and link performance is analyzed using average Bit Error Rate (BER), in different pilot symbol scenarios. In a typical laboratory environment, the results of BER versus receiver gain show that with 4 pilot symbols out of 128 carriers, at a gain of 20 dB, BER is 0.160922, which is reduced to 0.136884 with 16 pilot symbols. The developed link helps OFDM researchers to mitigate different challenges posed by the wireless environment and thereby strengthen OFDM technology.
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Authors and Affiliations

Nandana Narayana
1
Pallaviram Sure
1

  1. Department of Electronics and Communication Engineering, MS Ramaiah University of Applied Sciences, Bangalore, India
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Abstract

In the current smart tech world, there is an immense need of automating tasks and processes to avoid human intervention, save time and energy. Nowadays, mobile phones have become one of the essential things for human beings either to call someone, connect to the internet, while driving people need mobile phones to receive or make a call, use google maps to know the routes and many more. Normally in cars, mobile holders are placed on the dashboard to hold the mobile and the orientation of the phone needs to be changed according to the driver's convenience manually, but the driver may distract from driving while trying to access mobile phone which may lead to accidents. To solve this problem, an auto adjustable mobile holder is designed in such a way that it rotates according to the movement of the driver and also it can even alert the driver when he feels drowsiness. Image Processing is used to detect the movement of the driver which is then processed using LabVIEW software and NI myRIO hardware. NI Vision development module is used to perform face recognition and servo motors are used to rotate the holder in the required position. Simulation results show that the proposed system has achieved maximum accuracy in detecting faces, drowsiness and finding the position coordinates.
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Authors and Affiliations

Srilatha Madhunala
1
Bhavya Kanneti
1
Priya Anathula
1

  1. Department of ECE, Vardhaman College of Engineering, India
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Abstract

As a consequence of recent implementations of EU Directives related to noise protection more and more students of various AGH-UST programs are introduced to the basics of acoustic measurements. Students at various levels of theoretical background in the field of acoustic measurements are offered practical training in measurements using digital sound analyzers. The situation would be optimal if each student could have a device at his/her own disposal. Unfortunately, such a situation is not possible at the moment because of various reasons.

With the above problem in mind, a dedicated software package has been developed, implemented in the LabVIEW environment, which allows detailed studies of problems related to the acoustic signal measurement using sound level meters, as well as tasks in spectral analysis (1/1 and 1/3 band filters) and narrow-band (FFT) analysis. With such organization during the introductory laboratory classes each student is offered a direct individual contact with a virtual device that is properly pre-programmed for realization of a well-constructed learning process. It definitely facilitates understanding of the essence of acoustic signal measurements and provides a good basis for further laboratory work carried out as a team-activity.

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Authors and Affiliations

Robert Barański
Grażyna Wszołek
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Abstract

Electronic voltage transformers (EVT) and electronic current transformers (ECT) are important instruments in a digital substation. For simple, rapid and convenient development, the paper proposed an on-site calibration system for electronic instrument transformers based on LabVIEW. In the system, analog signal sampling precision and dynamic range are guaranteed by the Agilent 3458A digital multimeter, and data synchronization is also achieved based on a self-developed PCI synchronization card. To improve the measurement accuracy, an error correction algorithm based on the Hanning window interpolation FFT has good suppression of frequency fluctuation and inter-harmonics interference. The human-computer interface and analysis algorithm are designed based on LabVIEW, and the adaptive communication technology is designed based on IEC61850 9-1/2. The calibration system can take into account pairs of digital output and analog output of the electronic voltage/current transformer calibration. The results of system tests show that the calibration system can meet the requirements of 0.2 class calibration accuracy, and the actual type test and on-site calibration also show that the system is easy to operate with convenience and satisfactory stability.

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Authors and Affiliations

Ming Zhang
Kaicheng Li
Jun Wang
Shunfan He
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Abstract

In this paper the design and implementation of a plug-and-play analog resistance temperature sensor is presented. The smart temperature sensor consists of an analog sensor element with transducer electronic data sheet (TEDS) memory device and a network- capable application processor (NCAP) connected through a mixedmode interface (MMI). The mixed-mode interface and NCAP front-end electronic support have been implemented by the use of a standard 8-bit microcontroller. NCAP's application processing and network communication functions are implemented based on the concept of virtual instrumentation using a PC. The implemented NCAP can also be used as a plug-and-play stand-alone data acquisition system or as development system for plug-and-play sensors compliant with the IEEE 1451.4 standard. Details of sensor implementation and test results are included in the paper.

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Authors and Affiliations

Nenad Jevtic
Vujo Drndarevic

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