Class Testing

2002 ◽  
pp. 319-330
Keyword(s):  
2021 ◽  
Vol 11 (5) ◽  
pp. 2318
Author(s):  
David Macii ◽  
Daniel Belega ◽  
Dario Petri

The Interpolated Discrete Fourier Transform (IpDFT) is one of the most popular algorithms for Phasor Measurement Units (PMUs), due to its quite low computational complexity and its good accuracy in various operating conditions. However, the basic IpDFT algorithm can be used also as a preliminary estimator of the amplitude, phase, frequency and rate of change of frequency of voltage or current AC waveforms at times synchronized to the Universal Coordinated Time (UTC). Indeed, another cascaded algorithm can be used to refine the waveform parameters estimation. In this context, the main novelty of this work is a fair and extensive performance comparison of three different state-of-the-art IpDFT-tuned estimation algorithms for PMUs. The three algorithms are: (i) the so-called corrected IpDFT (IpDFTc), which is conceived to compensate for the effect of both the image of the fundamental tone and second-order harmonic; (ii) a frequency-tuned version of the Taylor Weighted Least-Squares (TWLS) algorithm, and (iii) the frequency Down-Conversion and low-pass Filtering (DCF) technique described also in the IEEE/IEC Standard 60255-118-1:2018. The simulation results obtained in the P Class and M Class testing conditions specified in the same Standard show that the IpDFTc algorithm is generally preferable under the effect of steady-state disturbances. On the contrary, the tuned TWLS estimator is usually the best solution when dynamic changes of amplitude, phase or frequency occur. In transient conditions (i.e., under the effect of amplitude or phase steps), the IpDFTc and the tuned TWLS algorithms do not clearly outperform one another. The DCF approach generally returns the worst results. However, its actual performances heavily depend on the adopted low-pass filter.


1999 ◽  
Vol 13 (1) ◽  
pp. 63-81 ◽  
Author(s):  
Mary B. Curtis ◽  
A. Faye Borthick

Many accounting firms have changed the way their auditors evaluate internal control. Instead of preparing flowcharts documenting transaction flows, they only document the controls that have a bearing on specific financial statement assertions. This shift in documentation marks a change in the structure of the internal control evaluation task from transaction flow to control objective. This case presents documentation organized by control objective for internal control of a company's purchasing cycle. The case includes discussion and objective format questions and is relatively short, which means it can be used as an in-class or out-of-class exercise or an in-class testing or assessment device on internal control evaluation.


2019 ◽  
Vol 22 (7) ◽  
pp. 1315-1348
Author(s):  
Neetu Jain ◽  
Rabins Porwal ◽  
Sumit Kumar ◽  
Sapna Varshney ◽  
Mukesh Saraswat

2014 ◽  
Vol 134 (1) ◽  
pp. 90-92 ◽  
Author(s):  
John L. Reagan ◽  
Randall R. Ingham ◽  
Samir Dalia ◽  
James N. Butera ◽  
Joseph D. Sweeney

2000 ◽  
Vol 28 (1) ◽  
pp. 34-42 ◽  
Author(s):  
Chris Sadler ◽  
Sandeep K. S. Gupta ◽  
Rohit Bhatia
Keyword(s):  

2020 ◽  
Author(s):  
Julia Miloczki ◽  
Anna Wawra ◽  
Markus Gansberger ◽  
Philipp Hummer ◽  
Taru Sandén

<p>With the Tea Bag Index (TBI) App, we aim to foster awareness of the importance of soils and their ecosystem services to students above the age of 10. The TBI app consists of three categories of hands-on activities: Basic soil attributes, Soil observations, and Tea Bag Index. Basic soil attributes include land use, soil colour and soil life, whereas soil observations go further to Texture by Feel, Spade Test and observation of soil pollution. The Tea Bag Index (Keuskamp et al., 2013) provides an easy and scientifically recognized way to measure decomposition rates and stabilisation of organic matter in soils. The method consists of burying tea bags and measuring the degradation of organic material after three months’ time. Each of the methods includes clear instructions and extra information in the app. Data gathered are interactively shown on a map in the App as well as online. Hence, students are encouraged to gain hands-on science experience and to witness how science connects across regions, countries and cultures. By using playful tools such as rewards, badges and a point system, we attract and maintain the interest of students. Social media channels are used to exchange and share their results as well as to reach teachers and citizen scientists in order to inspire them to use the educational App.</p><p>Having this awareness on soil and its functions, citizen scientists can make valuable contributions to the sustainable use of soils. They also have the opportunity to participate in a global scientific initiative, acquire skills in conducting a scientific experiment and gain knowledge on soil functions. The science community, on the other hand, increases its understanding of factors influencing decomposition (and associated soil functions) at different times and in different places globally.</p><p>Moreover, the TBI App can be used for „Content Language Integrated Lessons“ (CLIL), which is the use of a foreign language for the integrative teaching of content and language competence outside of language teaching in agricultural schools in Austria. Individual learning outcomes (ILOs) of an agricultural school class testing the TBI App were evaluated in an online questionnaire. Results showed high appreciation of activities offered by the TBI App and high motivation of students to contribute to science.</p><p> </p><p> </p><p>Keuskamp, J.A., Dingemans, B.J.J., Lehtinen, T., Sarneel, J.M. and Hefting, M.M. (2013), Tea Bag Index: a novel approach to collect uniform decomposition data across ecosystems. Methods Ecol Evol, 4: 1070-1075. doi:10.1111/2041-210X.12097</p>


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