Article Summaries

The Jitter Measurement Ways: The Jitter Decomposition

Eulalia Balestrieri, Luca De Vito, Francesco Lamonaca, Francesco Picariello, Sergio Rapuano, and Ioan Tudosa

Summary

 

Today, several applications and technologies require a suitable jitter characterization. For this reason, measurement methods and instruments aimed at quantifying and analyzing jitter continue to be proposed and developed by the research community and manufacturers. Jitter is often the joint effect of different phenomena, and it can have many components with different characteristics and sources. As a consequence, jitter decomposition represents an essential analysis tool which is used in several application fields aimed at improving system and component design performance. Depending on the aim of the decomposition, several approaches can be found in the literature which are used to split the overall jitter into its elementary components. To help engineers dealing with the jitter decomposition, the paper provides an overview of the main decomposition approaches and highlights their limitations and advantages.

 

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Developing an Automated Transition Stage as a Way to Improve the Quality of the Measurements Accuracy

Sameh M. Reda and Samaa M. Faramawy 

Summary

The differences in repeatability measurements between one operator than another will affect the accuracy, precision and hence the uncertainty of the same device measurements. To try to avoid or reduce the variation in repeatability measurements between each operator, a special automated translation stage was designed to improve the accuracy of measurements at defined positions. This automated stage was applied to measure the irradiance levels of two phototherapy luminaires as an example of an exposing cabinet. The standard regulations recommend that the irradiance level of any exposed area must be collected at specified positions. The results of using an automated stage show that there are personal errors affecting the manual repeatability measurements. Using the automated stage in collecting data, the standard deviation of repeatability decreased significantly by 87.5% for LED luminaire and 43.3% for the fluorescent lamps luminaire. Besides, the automated stage saved the time and energy of the operator in the most accurate way.

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Quality of Data Measurements in the Big Data Era: Lessons Learned from MIDAS Project

 

Gorka Epelde, Andoni Beristain, Roberto Álvarez, Mónica Arrúe, Iker Ezkerra, Oihana Belar, Roberto Bilbao, Gorana Nikolic, Xi Shi, Bart De Moor, and Maurice Mulvenna

 

Summary

 

In this paper, [the authors] report on the Quality of Data (QoD) challenges, approaches, and experience gained in the Meaningful Integration of Data Analytics and Services (MIDAS) project, whose aim is data-enabled policy making in healthcare. The MIDAS Project aims to map, acquire, manage, model, process and exploit existing heterogeneous health care data and other governmental data along with external open data to enable the creation of evidence-based actionable information and drive policy improvements in the European health sector (implementing four pilots in different EU countries with the participation of the corresponding health department and public health provider). Due to characteristics of the project, the following reporting is focused on QoD on provided datasets’ ingestion and processing and not in the uncertainty measurement on the data acquisition from empirical world. [The authors] elaborate on the following topics: Data quality dimensions to be better understood with respect to QoD context, data quality indicators to provide decision makers with reliability information and methods for evaluating QoD; and challenges identified and approaches followed to assure QoD in the context of a healthcare BD project, the MIDAS project.

 

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Low-Cost MEMS Accelerometer Network for Rotating Machine Vibration Diagnostics


Luciane Agnoletti dos Santos Pedotti, Ricardo Mazza Zago, Mateus Giesbrecht, and Fabiano Fruett

Summary

This paper presented a low-cost wireless sensor network dedicated to measure and process vibration in rotating machines, serving as a tool to aid in fault diagnosis. The sensor node was called the Vibration Monitor. Two of those sensors were installed into the experimental apparatus to measure the vibration simultaneously as a network. The sensor nodes acquired the data from tri-axial accelerometers. The X and Y axes had their signals acquired and processed
using an FFT algorithm to obtain its vibration spectrum. With this spectrum of machine speeds, the microcontroller calculates the six first harmonic orders concerning the machine speed. The system sent these six harmonic values to the cloud where they were computed for the X and Y axes for each node.

This text was taken from the article.

 


 

Measurement of the Instantaneous In-Cylinder Pressure of Reciprocating Compressors Using the Connecting Rod Strain

Leonardo do Nascimento Cervelin, Diego Henrique Sertich Arruda, Rodolfo César Costa Flesch, and Julio Nelson Scussel

Summary

The measurement of in-cylinder pressure during operation in reciprocating compressors is usually done in a destructive test in which a small bore is machined in the side of the cylinder. This instrumentation process not only impacts the real clearance volume of the compressor but also adds undesired dynamics to the measured value. This paper proposes a novel method for pressure measurement based on the connecting rod strain which solves most of the limitations of traditional methods. Experimental results obtained with a refrigeration compressor indicate that the proposed method presents errors smaller than ±0.2 bar for a coverage probability of 95% when compared with the values measured by a reference piezoelectric pressure transducer. The results are at least equivalent to the ones presented by traditional in-cylinder pressure measurement methods, but the proposed method uses a simpler setup and does not affect the compressor working condition.

This text was taken from the article.

 


 

Wearable Smart Multimeter Equipped with AR Glasses Based on IoT Platform

Kun Xia, Tianci Tang, Zheng Mao, Zihan Zhang, Hanfei Qu, and Han Li

Summary

A wearable smart measurement system equipped with monocular augmented reality (AR) glasses and Wi-Fi and Bluetooth modules is designed, which is more suitable for high-altitude measurement occasions than traditional digital multimeters (DMM). The measurement data could be displayed on AR glasses supported by Bluetooth module in real time. Also, the effective management of large-scale industrial measurement data could be implemented through the IoT data interaction platform with high speed communication by employing a Wi-Fi module. In addition, the wire-receiving device is introduced into the system, which effectively solves the problem that occurs when the traditional DMM harness is tangled. Hall sensors are adopted to measure the current and solves the problem that the traditional DMM needs to be connected into an electronic circuit in series.

This text was taken from the article.

 


 

Timing Pulses through Coaxial Cables

Gihan Gomah Hamza

Summary

Timing pulses are used for time and phase synchronization in many applications such as telecommunication networks and timing laboratories. These signals could not perform this task efficiently or accurately if the time delay added by the cables they are passing through were unknown. This article shows that cable delay not only depends on the cable length but also on the specifications of the signal passing through it. The article provides an overview of the international classifications of time measurements and where cable delay measurements are allocated. Then, the problems encountered in a previous international comparison in cable delay measurement is explored. The results of measuring three cables were connected to the results of the international comparison to verify the sources of these deficiencies. The results are discussed and the main parameters that degrade the accuracy of cable delay measurement are determined. Finally, a possible solution is proposed.

This text was taken from the article.

 


 

--- Columns ---

Life After Graduation

About Topics of Interest to I&M

Vincenzo Marletta

“Dear readers, in this issue of the Magazine you have contributions on some topics of interest to our measurement sector. But, when is a topic interesting for our community? How do you define one topic more interesting than another?... The answer seems quite obvious, just look at the literature to find out what the researchers are searching for more or pouring their efforts into. And, so I started browsing the web. I searched for the companies and publishers that publish magazines dedicated to issues related to instrumentation, measurements, and sensors… Just for the sake of brevity, I report the results obtained by the IEEE Xplore search engine.”

This is a small glimpse of text from the column.