Relevant bibliographies by topics / DID estimation

Academic literature on the topic 'DID estimation'

Author: Grafiati
Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "DID estimation"

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Raza, Sohail, and Shahzad Munir. "Did Demonetization Affect Indian Stock Market?" International Research Journal of Business Studies 15, no. 1 (June 24, 2022): 1–15. http://dx.doi.org/10.21632/irjbs.15.1.1-15.

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This study explores the impact of ”2016 demonetization” on the stock market in India. The policy declared 86% of cash in circulation in the form of Indian rupees (INR) 500 & 1000 notes as an illegal tender effective from midnight of November 8, 2016. However, India’s government progressively released new 500 and 2000 INR notes over the next few months. Following the demonetization announcement, stock prices of cash-sensitive industries like consumer goods and financial services dropped rapidly, reflecting a significant reduction in demand. This study focuses on the short-term effects of demonetization on the stock prices of 100 publicly listed firms using their daily stock data. We use estimating windows within 60 days of the announcement and then capture the short-term effects of demonetization by employing the Ordinary Least Square (OLS), the Fixed Effect (FE), and the Random Effect (RE) methods. Estimation results demonstrate that demonetization effectively decreases stock prices.
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Mohd Shariff, Khairul Khaizi, Suraya Zainuddin, Noor Hafizah Abdul Aziz, Nur Emileen Abd Rashid, and Nor Ayu Zalina Zakaria. "Spectral estimator effects on accuracy of speed-over-ground radar." International Journal of Electrical and Computer Engineering (IJECE) 12, no. 4 (August 1, 2022): 3900. http://dx.doi.org/10.11591/ijece.v12i4.pp3900-3910.

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<p>Spectral estimation is a critical signal processing step in speed-over-ground (SoG) radar. It is argued that, for accurate speed estimation, spectral estimation should use low bias and variance estimator. However, there is no evaluation on spectral estimation techniques in terms of estimating mean Doppler frequency to date. In this paper, we evaluate two common spectral estimation techniques, namely periodogram based on Fourier transformation and the autoregressive (AR) based on burg algorithm. These spectral estimators are evaluated in terms of their bias and variance in estimating a mean frequency. For this purpose, the spectral estimators are evaluated with different Doppler signals that varied in mean frequency and signal-to-noise ratio (SNR). Results in this study indicates that the periodogram method performs well in most of the tests while the AR method did not perform as well as these but offered a slight improvement over the periodogram in terms of variance.</p>
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Ashkenazi, Sarit, Yarden Gliksman, and Avishai Henik. "Understanding Estimations of Magnitudes: An fMRI Investigation." Brain Sciences 12, no. 1 (January 12, 2022): 104. http://dx.doi.org/10.3390/brainsci12010104.

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The current study examined whether discrete numerical estimation is based on the same cognitive process as estimation of continuous magnitudes such as weight and time. While the verbal estimation of numerical quantities has a contingent unit of measurement (e.g., how many cookies fit in a cookie jar? _X_ cookies), estimation of time and weight does not (e.g., how much time does it take to fill a bath with water? _X_ minutes/hours/seconds). Therefore, estimation of the latter categories has another level of difficulty, requiring extensive involvement of cognitive control. During a functional magnetic resonance imaging (fMRI) scan, 18 students performed estimations with three estimation categories: number, time, and weight. Estimations elicited activity in multiple brain regions, mainly: (1) visual regions including bilateral lingual gyrus), (2) parietal regions including the left angular gyrus and right supramarginal gyrus, and (3) the frontal regions (cingulate gyrus and the inferior frontal cortex). Continuous magnitude estimations (mostly time) produced different frontal activity than discrete numerical estimations did, demonstrating different profiles of brain activations between discrete numerical estimations and estimations of continuous magnitudes. The activity level in the right middle and inferior frontal gyrus correlated with the tendency to give extreme responses, signifying the importance of the right prefrontal lobe in estimations.
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Rendon, Silvio. "A truth commission did not tell the truth: A rejoinder to Manrique-Vallier and Ball." Research & Politics 6, no. 2 (April 2019): 205316801984097. http://dx.doi.org/10.1177/2053168019840972.

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Rendon (2019) showed that the indirect estimation of total killings in the Peruvian Truth and Reconciliation Commission introduced a distortion. Two of the original analysts, Manrique-Vallier and Ball (2019), provide an indirect defense of their work using new data, and argue that this supports their unprecedented indirect method over the direct estimator. In this rejoinder I show that their new figure of 17,687 killings by the Shining Path is closer to the direct estimate of 18,341 than to their indirect estimate of 31,331 killings. I also show that the indirect method systematically produces impossible negative predicted killings and overfits massively. I reiterate my conclusion that their indirect estimates are unreliable and should be retracted.
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Ashkenazi, Sarit, and Yulia Tsyganov. "The Cognitive Estimation Task is nonunitary: Evidence for multiple magnitude representation mechanisms among normative and ADHD college students." Journal of Numerical Cognition 2, no. 3 (February 10, 2017): 220–46. http://dx.doi.org/10.5964/jnc.v2i3.3.

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There is a current debate on whether the cognitive system has a shared representation for all magnitudes or whether there are unique representations. To investigate this question, we used the Biber cognitive estimation task. In this task, participants were asked to provide estimates for questions such as, “How many sticks of spaghetti are in a package?” The task uses different estimation categories (e.g., time, numerical quantity, distance, and weight) to look at real-life magnitude representations. Experiment 1 assessed (N = 95) a Hebrew version of the Biber Cognitive Estimation Task and found that different estimation categories had different relations, for example, weight, time, and distance shared variance, but numerical estimation did not. We suggest that numerical estimation does not require the use of measurement in units, hence, it represents a more “pure” numerical estimation. Experiment 2 found that different factors explain individual abilities in different estimation categories. For example, numerical estimation was predicted by preverbal innate quantity understanding (approximate number sense) and working memory, whereas time estimations were supported by IQ. These results demonstrate that cognitive estimation is not a unified construct.
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Weskott, Johannes B. D. "Unemployment Compensation and Wages: A Difference-in-Differences Approach to Assessing the Wage Effects of the German Hartz Reforms." Jahrbücher für Nationalökonomie und Statistik 240, no. 1 (January 28, 2020): 89–110. http://dx.doi.org/10.1515/jbnst-2018-0020.

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AbstractThis paper examines the influence of the level of unemployment assistance (Arbeitslosengeld II) on the wage level by exploiting a quasi-natural experiment formed by the German Hartz reforms in 2005. Estimations are based on data from the Socioeconomic Panel ranging from 2000 to 2007. As dependent variables both real monthly gross salary and real hourly gross wage are used. Firstly, following the approach taken by Arent and Nagl (2013, Unemployment Compensation and Wages: Evidence from the German Hartz Reforms. Jahrbücher für Nationalökonomie und Statistik 233 (4): 450–466), a before-after estimator is applied. Secondly, in contrast to the replication study by Ludsteck and Seth (2014, Comment on „Unemployment Compensation and Wages: Evidence from the German Hartz Reforms“ by Stefan Arent and Wolfgang Nagl. Jahrbücher für Nationalökonomie und Statistik 234 (5): 635–644) a control group is constructed and a difference-in-differences estimator (DiD) is used for further assessment. The results of the before-after estimation indicate a negative influence of the unemployment assistance reform on wages. However, the corresponding placebo regressions cast doubt on whether the estimated effect is a policy effect. The DiD approach shows that substantial time effects exist. This indicates that the before-after estimator is not suitable for assessing the policy effect. Applying the DiD estimator, a negative significant policy effect is only identified for men in West Germany.
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Hosoda, Shion, Tsukasa Fukunaga, and Michiaki Hamada. "Umibato: estimation of time-varying microbial interaction using continuous-time regression hidden Markov model." Bioinformatics 37, Supplement_1 (July 1, 2021): i16—i24. http://dx.doi.org/10.1093/bioinformatics/btab287.

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Abstract Motivation Accumulating evidence has highlighted the importance of microbial interaction networks. Methods have been developed for estimating microbial interaction networks, of which the generalized Lotka–Volterra equation (gLVE)-based method can estimate a directed interaction network. The previous gLVE-based method for estimating microbial interaction networks did not consider time-varying interactions. Results In this study, we developed unsupervised learning-based microbial interaction inference method using Bayesian estimation (Umibato), a method for estimating time-varying microbial interactions. The Umibato algorithm comprises Gaussian process regression (GPR) and a new Bayesian probabilistic model, the continuous-time regression hidden Markov model (CTRHMM). Growth rates are estimated by GPR, and interaction networks are estimated by CTRHMM. CTRHMM can estimate time-varying interaction networks using interaction states, which are defined as hidden variables. Umibato outperformed the existing methods on synthetic datasets. In addition, it yielded reasonable estimations in experiments on a mouse gut microbiota dataset, thus providing novel insights into the relationship between consumed diets and the gut microbiota. Availability and implementation The C++ and python source codes of the Umibato software are available at https://github.com/shion-h/Umibato. Supplementary information Supplementary data are available at Bioinformatics online.
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Ezrati-Vinacour, Ruth, and Iris Levin. "Time Estimation by Adults Who Stutter." Journal of Speech, Language, and Hearing Research 44, no. 1 (February 2001): 144–55. http://dx.doi.org/10.1044/1092-4388(2001/013).

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In view of the fact that stuttering involves time pressure in communicative contexts, the aim of this investigation was to study the effect of stuttering on time estimation. Two matching groups of 47 adults each, one consisting of stutterers and the other of fluent speakers, estimated the duration of four verbal tasks—two that involved speaking and two that did not. Two methods of time estimation were used: production and reproduction. In production, participants were required to perform a task, terminating it when they felt that the specified interval had elapsed. In reproduction, participants were asked to estimate the duration of a task immediately after being stopped by the experimenter. The results reveal that the differences in time estimation between adults who stutter and fluent speakers were task dependent, with the stutterers estimating time less accurately on oral verbal tasks. The conversation task in particular highlighted the inaccuracy of their time estimation. Furthermore, severe stutterers estimated time less accurately than mild stutterers. The greatest inaccuracy was displayed by severe stutterers when estimating the time of an oral task by the production method. The results are discussed in terms of cognitive models based on attention to time, method measurement, and mental workload. Clinical implications are also suggested.
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Samuelsson, Oscar, Anders Björk, Jesús Zambrano, and Bengt Carlsson. "Gaussian process regression for monitoring and fault detection of wastewater treatment processes." Water Science and Technology 75, no. 12 (March 25, 2017): 2952–63. http://dx.doi.org/10.2166/wst.2017.162.

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Monitoring and fault detection methods are increasingly important to achieve a robust and resource efficient operation of wastewater treatment plants (WWTPs). The purpose of this paper was to evaluate a promising machine learning method, Gaussian process regression (GPR), for WWTP monitoring applications. We evaluated GPR at two WWTP monitoring problems: estimate missing data in a flow rate signal (simulated data), and detect a drift in an ammonium sensor (real data). We showed that GPR with the standard estimation method, maximum likelihood estimation (GPR-MLE), suffered from local optima during estimation of kernel parameters, and did not give satisfactory results in a simulated case study. However, GPR with a state-of-the-art estimation method based on sequential Monte Carlo estimation (GPR-SMC) gave good predictions and did not suffer from local optima. Comparisons with simple standard methods revealed that GPR-SMC performed better than linear interpolation in estimating missing data in a noisy flow rate signal. We conclude that GPR-SMC is both a general and powerful method for monitoring full-scale WWTPs. However, this paper also shows that it does not always pay off to use more sophisticated methods. New methods should be critically compared against simpler methods, which might be good enough for some scenarios.
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Bordo, Michael D., and Angela Redish. "Why Did the Bank of Canada Emerge in 1935?" Journal of Economic History 47, no. 2 (June 1987): 405–17. http://dx.doi.org/10.1017/s0022050700048154.

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Three possible explanations for the emergence of the Canadian central bank in 1935 are examined: that it reflected the need of competitive banking systems for a lender of last resort, that it was necessary to anchor the unregulated Canadian monetary system after abandonment of the gold standard in 1929, and that it was a response to political rather than purely economic pressures. Evidence from a variety of sources (contemporary statements to a Royal Commission, correspondence of chartered bankers, newspaper reports, academic writings, and estimation of time series econometric models) rejects the first two hypotheses and supports the third.
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Dissertations / Theses on the topic "DID estimation"

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Ertugrul, Nesimi. "Position estimation and performance prediction for permanent-magnet motor drives." Thesis, Online version, 1993. http://ethos.bl.uk/OrderDetails.do?did=1&uin=uk.bl.ethos.357041.

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Luo, Cheng. "On XML selectivity estimation /." Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1456296461&sid=11&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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Liu, Zhe. "Distributed estimation in heavy-tailed environments." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 65 p, 2009. http://proquest.umi.com/pqdweb?did=1885755971&sid=10&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Rioux, Isabelle. "Time estimation in chronic insomnia sufferers." Master's thesis, Université Laval, 2003. http://proquest.umi.com/pqdweb?did=766731671&sid=9&Fmt=2&clientId=9268&RQT=309&VName=PQD.

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Chen, Hao. "Noise enhanced signal detection and estimation." Related electronic resource:, 2007. http://proquest.umi.com/pqdweb?did=1342743841&sid=2&Fmt=2&clientId=3739&RQT=309&VName=PQD.

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Kodali, Mallika. "Fusion algorithms for decentralized estimation of parameter /." Available to subscribers only, 2005. http://proquest.umi.com/pqdweb?did=1075698501&sid=15&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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Zhang, Yuzhao. "Essays on return predictability and volatility estimation." Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1666139151&sid=3&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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Qi, Zhen. "Pose estimation using points to regions correspondence." Laramie, Wyo. : University of Wyoming, 2008. http://proquest.umi.com/pqdweb?did=1663060061&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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Srivastava, Mayank. "Estimation of coalbed methane production potential through reservoir simulation /." Available to subscribers only, 2005. http://proquest.umi.com/pqdweb?did=1079667111&sid=4&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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Nota, Martin. "Estimation of the Slovak Beveridge curve using regional data." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 76 p, 2008. http://proquest.umi.com/pqdweb?did=1597632411&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Books on the topic "DID estimation"

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Mathes, Harald. Der PLS-Ansatz für die Analyse von Pfadmodellen. Frankfurt am Main: Anton Hain, 1993.

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Duclos, Jean-Yves. Poverty and equity: Measurement, policy and estimation with DAD. New York, NY: Springer, 2005.

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Abdelkrim, Araar, ed. Poverty and equity: Measurement, policy and estimation with DAD. New York: Springer, 2006.

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Marone, Enrico, ed. Le grandi infrastrutture: approcci di ordine giuridico, economico ed estimativo. Florence: Firenze University Press, 2005. http://dx.doi.org/10.36253/8884533066.

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Roussos, Louis A. Theoretical formula for statistical bias in CATSIB DIF estimator due to discretization of the ability scale. Newtown, PA: Law School Admission Council, 2006.

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Bracher, Astrid. Photoacclimation of phytoplankton in different biogeochemical provinces of the Southern Ocean and its significance for estimating primary production =: Die Photoakklimatisierung von Phytoplankton in verschiedenen biogeochemischen Provinzen des Antarktischen Ozeans und ihre Bedeutung für die Abschätzung der Primärproduktion. Bremerhaven: Alfred-Wegener-Institut für Polar- und Meeresforschung, 1999.

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Powell, David. Did the Economic Stimulus Payments of 2008 Reduce Labor Supply? Evidence from Quantile Panel Data Estimation. RAND Corporation, 2014. http://dx.doi.org/10.7249/wr710-3.

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Duclos, Jean-Yves, and Abdelkrim Araar. Poverty and Equity: Measurement, Policy and Estimation with DAD. Springer London, Limited, 2007.

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Cernat, Alexandru, and Joseph W. Sakshaug, eds. Measurement Error in Longitudinal Data. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198859987.001.0001.

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Understanding change is essential in most scientific fields. This is highlighted by the importance of issues such as shifts in public health and changes in public opinion regarding politicians and policies. Nevertheless, our measurements of the world around us are often imperfect. For example, measurements of attitudes might be biased by social desirability, while estimates of health may be marred by low sensitivity and specificity. In this book we tackle the important issue of how to understand and estimate change in the context of data that are imperfect and exhibit measurement error. The book brings together the latest advances in the area of estimating change in the presence of measurement error from a number of different fields, such as survey methodology, sociology, psychology, statistics, and health. Furthermore, it covers the entire process, from the best ways of collecting longitudinal data, to statistical models to estimate change under uncertainty, to examples of researchers applying these methods in the real world. The book introduces the reader to essential issues of longitudinal data collection such as memory effects, panel conditioning (or mere measurement effects), the use of administrative data, and the collection of multi-mode longitudinal data. It also introduces the reader to some of the most important models used in this area, including quasi-simplex models, latent growth models, latent Markov chains, and equivalence/DIF testing. Further, it discusses the use of vignettes in the context of longitudinal data and estimation methods for multilevel models of change in the presence of measurement error.
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Book chapters on the topic "DID estimation"

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Kosambi, D. D. "The Estimation of Map Distances from Recombination Values." In D.D. Kosambi, 125–30. New Delhi: Springer India, 2016. http://dx.doi.org/10.1007/978-81-322-3676-4_16.

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Casas, Leslie, Chris Mürwald, Felix Achilles, Diana Mateus, Dietrich Huber, Nassir Navab, and Stefanie Demirci. "Human Pose Estimation from Pressure Sensor Data." In Bildverarbeitung für die Medizin 2018, 285–90. Berlin, Heidelberg: Springer Berlin Heidelberg, 2018. http://dx.doi.org/10.1007/978-3-662-56537-7_77.

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Mordhorst, Laurin, Maria Morozova, Sebastian Papazoglou, Björn Fricke, Jan M. Oeschger, Henriette Rusch, Carsten Jäger, Markus Morawski, Nikolaus Weiskopf, and Siawoosh Mohammadi. "Human Axon Radii Estimation at MRI Scale." In Bildverarbeitung für die Medizin 2021, 180–85. Wiesbaden: Springer Fachmedien Wiesbaden, 2021. http://dx.doi.org/10.1007/978-3-658-33198-6_45.

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Robert, Laurent. "Estimation of Digital Image Correlation (DIC) Performances." In Experimental Analysis of Nano and Engineering Materials and Structures, 347–48. Dordrecht: Springer Netherlands, 2007. http://dx.doi.org/10.1007/978-1-4020-6239-1_172.

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Keysers, Daniel, Sami Celik, Henning Braess, Jörg Dahmen, and Hermann Ney. "Parameter Estimation for Automatic Dose Control in Radioscopy." In Bildverarbeitung für die Medizin 2002, 279–82. Berlin, Heidelberg: Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/978-3-642-55983-9_64.

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Grimm, Robert, Johann Sukkau, Joachim Hornegger, and Günther Greiner. "Automatic Patient Pose Estimation Using Pressure Sensing Mattresses." In Bildverarbeitung für die Medizin 2011, 409–13. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-19335-4_84.

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Wirkert, Sebastian J., Anant S. Vemuri, Hannes G. Kenngott, Sara Moccia, Michael Götz, Benjamin F. B. Mayer, Klaus Hermann Maier-Hein, Daniel S. Elson, and Lena Maier-Hein. "Abstract: Physiological Parameter Estimation from Multispectral Images Unleashed." In Bildverarbeitung für die Medizin 2018, 36. Berlin, Heidelberg: Springer Berlin Heidelberg, 2018. http://dx.doi.org/10.1007/978-3-662-56537-7_22.

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Steckenleiter, Carina. "Wie viel Training brauchen Arbeitslose?" In Die Wirtschaft im Wandel, 183–87. Wiesbaden: Springer Fachmedien Wiesbaden, 2021. http://dx.doi.org/10.1007/978-3-658-31735-5_29.

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ZusammenfassungDie Bekämpfung der Arbeitslosigkeit ist eines der wichtigsten Ziele der Wirtschaftspolitik. Jährlich wenden Industrienationen beträchtliche Summen an Geldern für Arbeitsmarktprogramme auf. Laut einer vergleichenden Aufstellung der OECD entsprachen im Jahr 2015 die Ausgaben für aktive Arbeitsmarktprogramme in Deutschland beispielsweise 0,6 % des Bruttoinlandsprodukts (BIP) und in Frankreich 1 % des BIPs. Vor dem Hintergrund dieser hohen Kosten sind belastbare Auswertungen, die die Wirkung der Programme evaluieren, von immenser Bedeutung. Die Autoren der vorliegenden Studie evaluieren dabei insbesondere den Effekt der Dauer eines Arbeitsmarktprogramms.Flores, Carlos A., Alfonso Flores-Lagunes, Arturo Gonzalez, und Todd C. Neumann (2012), Estimating the Effects of Length of Exposure to Instruction in a Training Program: The Case of Job Corps, Review of Economics and Statistics 94(1), 153–171.
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Werner, René, Jan Ehrhardt, Alexander Schmidt-Richberg, Florian Cremers, and Heinz Handels. "Estimation of Inner Lung Motion Fields by Non-linear Registration." In Bildverarbeitung für die Medizin 2009, 102–6. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-93860-6_21.

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Wachinger, Christian, Ramtin Shams, and Nassir Navab. "Towards an Estimation of Acoustic Impedance from Multiple Ultrasound Images." In Bildverarbeitung für die Medizin 2009, 405–9. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-93860-6_82.

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Conference papers on the topic "DID estimation"

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Iseki, Toshio. "A Study on Akaike’s Bayesian Information Criterion in Wave Estimation." In ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2011. http://dx.doi.org/10.1115/omae2011-49170.

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A feasibility study of Bayesian wave estimation was carried out to investigate the relationship between the minimum Akaike’s Bayesian information criterion (ABIC) and the estimated wave parameters. The ship response functions, which were used for the Bayesian wave estimation together with the ship motion cross spectra, were simply modified and compared with the normal response functions in connection with the accuracy of estimated wave parameters. Moreover, the concept of the ABIC surfaces was introduced to investigate the optimum estimates from the stochastic viewpoint and the physical viewpoint. As the result, it was revealed that the minimum ABIC did not always provide the best estimates from the viewpoint of wave estimation and the simply modified response functions could reduce the estimating errors in some cases. The reasons were considered that the estimating error at the sharp peak of response amplitude operators was closely related to existence of the local minima of the ABIC surface and the simply modified response functions had some effects to make the ABIC surface smoother. It is pointed out as the conclusion of this report that any estimating errors of the ship response functions were not considered in the Bayesian modeling.
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Yoshikawa, Takaya, Nobuyuki Hotta, and Masaya Ito. "Estimation of the Fracture Origin of Ceramic Gas Turbine Rotors." In ASME 1995 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1995. http://dx.doi.org/10.1115/95-gt-250.

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The fracture origin of ceramic gas turbine rotors has been estimated by photographing the moment of burst during high speed spinning. Three types of ceramic rotors were designed to induce a fracture at the surface, the inside, and a pre-defect area. From photographic analysis of typical fracture behavior of these rotors, the fracture origins of ceramic rotors were estimated. The estimated fracture origins did not correspond to the calculated maximum stress areas in the rotors.
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Klimenko, N. N. "Estimation of the state of microbocenosis of the peach rhizosphere during the biologization of its cultivation." In CURRENT STATE, PROBLEMS AND PROSPECTS OF THE DEVELOPMENT OF AGRARIAN SCIENCE. Federal State Budget Scientific Institution “Research Institute of Agriculture of Crimea”, 2020. http://dx.doi.org/10.33952/2542-0720-2020-5-9-10-113.

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Our research has shown that the use of biologization techniques for growing peaches positively affected the number of bacteria of the main ecological and trophic groups involved in the transformation of soil organic matter: ammonifying bacteria ‒ by 26-47 %; amylolytic bacteria – by 48-103 %; phosphate mobilizing bacteria – by 32-72 %; oligonitrophilic bacteria – by 24-49 %; oligotrophic bacteria – by 57-59 %; cellulolytic bacteria – by 25-39 % in the soil layer of 0-30 and 30-60 cm compared to the control, respectively. There was a decrease in the number of micromycetes, which, in our opinion, is associated with the antagonistic effect of microbial preparations. The use of biologization techniques did not significantly affect the oligotrophy index: its values remained at the control level and fluctuated between 0.6 and 0.8, depending on the experiment variant. The values of the pedotrophy index of the soil of the experimental site on both backgrounds of grassing did not differ and amounted to 1.1 when using Azotobacterin and 1.0 – when bacterizing with CMP. Increasing values of this index indicate the transition of the studied biocenosis to a stable state.
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Cole, Daniel G. "Feedback Control and Exogenous Force Estimation for Improved Single-Molecule Experiments." In ASME 2010 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/detc2010-28735.

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This article explores two types of feedback used to control optical traps: position feedback, which was shown to be equivalent to force feedback, and integral feedback. The ability of each of these types of feedback to lower the measurement SNR in single molecule experiments is evaluated and compared to the open-loop case. While position feedback did not result in any improvement in the SNR, the case of integral feedback results in an improvement. Integral feedback is shown to improve the SNR of the measured signal of interest, and is relatively robust and easy to implement. It is also shown that integral feedback acts as an exogenous force estimator.
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Wang, Jinli, Fuyuan Yang, Minggao Ouyang, and Ying Huang. "A Research on Engine Phase and Speed Estimation Method Based on Cylinder Pressure Sensor." In ASME 2013 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icef2013-19025.

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Cylinder pressure based combustion state control is a direction that has drawn much attention in the field of internal combustion engine control, especially in the field of diesel HCCI (Homogeneous Charge Compression Ignition) research. In-cylinder pressure sensors have the potential to diagnose or even replace many traditional sensors, including camshaft and crankshaft sensors. This paper did research on engine synchronization method based on in-cylinder pressure signal. The research was based on a 4-cylinder high pressure common rail diesel engine equipped with 4 PSG (Pressure Sensor Glow Plug) type piezo-resistance cylinder pressure sensors, intended for HCCI research. Through theoretical analysis and experimental proof, methods and models for cylinder identification, engine phase estimation and engine speed estimation are given and further verified by experiments. Results show that cylinder pressure sensor could be used to identify cylinder instead of cam shaft sensor. The models for engine phase and speed estimation have been proved to have precision of 3° crank angle and 4.6rpm, respectively. The precision of engine phase and speed estimation provides a possibility for the engine to run if the crankshaft sensor fails, but more researches have to be carried out with respect to crankshaft sensor replacement.
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Kudo, Kenji, Shinji Kawatsuma, Hiroshi Rindo, Kozo Watabe, Hiroyuki Tomii, Kunio Shiraishi, Naoto Yagi, Tadashi Fukushima, and Tomohisa Zaitsu. "Comprehensive Cost Estimation Method for Decommissioning." In 14th International Conference on Nuclear Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/icone14-89586.

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Japan Atomic Energy Research Institute (JAERI) played a leading role in basic research in the field of atomic energy research and development, while Japan Nuclear Cycle Development Institute (JNC) did a major role in FBR cycle development and high level waste disposal. According to Japanese government’s decision in December 2001, JAERI and JNC was merged as of October 1st. 2005. The new organization, Japan Atomic Energy Agency (JAEA) is an institute for comprehensive R&D for atomic energy, and which is the largest research and development institute among Japanese Governmental organization. Its missions are basic research on atomic, R&D for nuclear fuel cycle, decommissioning and disposal for own facilities and waste, contribution to safety and non-proliferation, etc. The JAEA owns a number of nuclear facilities: research reactors such as JRR-2 and Joyo, prototype reactors such as ATR “Fugen” and FBR “Monju”, fuel cycle plants such as Uranium Enrichment Demonstration Plant at ningyo-toge, MOX fuel plants at Tokai, Reprocessing Plant at Tokai, and Hot Laboratories such as JRTF and FMF. As a part of preparation of the mergence, JNC and JAERI have jointly developed a comprehensive cost estimation method for decommissioning, based on decommissioning and upgrading experiences of JAERI and JNC. This method has adopted more estimation formulae for typical decommissioning activities than ever, so as to be more reliable. JAERI and JNC had estimated by using the comprehensive estimation method for decommissioning, and concluded the total cost for decommissioning would be 600 billion yen (approx. 5 billion USD).
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Gotoh, Koji, and Masahiro Toyosada. "A Practical Estimation Method of the Skin Plate Distortion Caused by Fillet Weld." In ASME 2002 21st International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2002. http://dx.doi.org/10.1115/omae2002-28181.

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Development of a useful estimation method of the welding deformation about welded built-up structures is developed in this paper. Improvement of matching accuracy of each hull block element is essential to introduce the economical automatic welding machines in an assembly stage. Precise estimation method of the welding deformation is also necessary to achieve the aim. Equivalent inherent strain method is highlighted as a convenient estimation method about welding deformation in large welded built-up structures. Inherent strain can be seen as the deformation source generated by welding and derives from the thermal cycles under welding processes. This deformation source can be given if the amount of welding heat input is known. The deformation can be calculated by elastic finite element analysis. Shell element is applied to simplify the mesh idealization. However, this method did not give a good estimation result in case that out-of-plane deformation such as a skin plate distortion occurs. Improvement of equivalent inherent strain method to advance the accuracy of estimation about the skin plate distortion caused by fillet weld is performed in this paper. Beam element, which expresses the fillet weld bead and has inherent strain along the bead to generate tendon force, is incorporated with former equivalent inherent strain method. The skin plate distortion measured are compared with the calculated one by applying the proposed method. As a result, the validity of the improvement is confirmed.
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Durfee, W. K., C. M. Hendrix, P. Cheng, and G. Varughese. "Influence of Haptic and Visual Displays on the Estimation of Virtual Environment Stiffness." In ASME 1997 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/imece1997-0388.

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Abstract Human subject experiments were performed to determine the influence of a visual display on the perception of haptic spring stiffness. Seven subjects participated in an experiment where they were presented with two virtual springs and asked to determine which was stiffer. The virtual springs were represented through a graphics display which they watched and a haptic display which they explored with their fingers. The relative visual to haptic stiffness was varied over a range. The results demonstrated that when subjects made errors in haptic stiffness estimation (which they did approximately 41% of the time), those errors tended to follow visual rather than haptic cues, particularly when the visual to haptic stiffness mismatch was large (30–40%). The results suggest that in some cases, visual cues can be used in virtual environments to compensate for deficiencies in haptic displays.
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Li, Hongtao, and Lili Wang. "Research on the Impact of China’s National Innovation City Pilot Policy on High-Efficiency Agglomeration—Estimation and Analysis Based on DID Models." In Fifth International Conference on Economic and Business Management (FEBM 2020). Paris, France: Atlantis Press, 2020. http://dx.doi.org/10.2991/aebmr.k.201211.007.

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Hamadate, Naoya, Keiichi Watanuki, and Kazunori Kaede. "Confidence Estimation in Multiple Choice Questions Using Eye Movements." In 13th International Conference on Applied Human Factors and Ergonomics (AHFE 2022). AHFE International, 2022. http://dx.doi.org/10.54941/ahfe1001801.

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In recent years, with the spread of electronic devices, e-learning has become a common form of learning, especially among students and other young people. One of the most common forms of e-learning is multiple-choice questions. While multiple-choice questions allow the learner to grasp the answer instantaneously and reliably, they also allow the learner to answer correctly by guesswork or chance, which may cause the learner to ignore content that should be reviewed. Therefore, it is important to estimate the confidence level from the learner's mental information. Eye movements are often used as a method of ascertaining learners' mental information. Previous studies have suggested that saccades are effective in discriminating comprehension of sentences, and pupil size is effective in evaluating English word acquisition. In addition, it has been confirmed that the fixation of multiple choice questions changes depending on the learner's confidence level. The purpose of this study was to evaluate the relationship between eye movements, such as saccades and pupil size, and the level of confidence in multiple-choice questions. As an experiment, we measured eye movements using four-choice questions on Japanese translation of English words. Thirty questions were designed to have varying degrees of difficulty. A tabletop eye movement measurement device was used for eye tracking. The flow of one trial is described below. The participant gazed at the English word on the monitor for 5 seconds. After that, four choices were displayed on the monitor, and the participants answered the questions. The participants were instructed to answer the question immediately after the choice was decided. Finally, a post-questionnaire was conducted. In the post-questionnaire, the participants were asked to answer one of the following questions: "I could answer the question without any choice," "I knew the answer by looking at the choices," "I did not know the answer but guessed from the choices," or "I do not know the answer at all. The experiment was conducted on seven Japanese male university students (23.3±1.6 years old) in a random order of 30 trials each. Saccade frequency and mean pupil size were used as evaluation indices. The percentage of fixation time in the answer choices was also evaluated based on previous studies. The confidence level was defined as "recall," "recognition," "guess," and "intuition," in descending order based on the responses to the post-questionnaire, and classified into four groups. The results of multiple comparison tests showed that the percentage of fixation time of the answer choices was significantly larger when the answer choice was "recall" than when the answer choice was "guess. On the other hand, there was no significant difference in saccade frequency and mean pupil size. The reason for the lack of differences may be that there were some trials in which the pupil size did not change because the time to answer the questions was too short. Therefore, as an experiment for improvement, we changed the contents of the multiple-choice questions and are studying the contents of questions that require more time. By increasing the answer time, we expect to see different characteristics of eye movements depending on the level of confidence from the previous experiment.
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Reports on the topic "DID estimation"

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Stastny, Petr, Robert Roczniok, Daniel Cleather, Martin Musalek, Dominik Novak, and Michal Vagner. Straight speed and acceleration optimal distances and reference values. A systematic review, and meta-analyses. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, May 2022. http://dx.doi.org/10.37766/inplasy2022.5.0010.

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Review question / Objective: To summarize the sprint reference acceleration and speed values for different sprint distances and suggest optimal unification of ice-hockey straight sprint testing. Eligibility criteria: The title and abstract screening was done by two researchers (PS and RR) who selected a set of articles for full text screening, where the inclusion criteria were: 1) male or female ice-hockey players; 2) any cross-sectional or intervention study; 3) tests of ice-hockey sprinting over any distance or any battery of conditioning tests that included straight-line sprints; and, 4) results reported straight-line sprint distance, speed, time, or acceleration. In the case of disagreement between the evaluating authors, the final decision was made by a third author (MV).The full text screening exclusion criteria were: 1) if the article was not in English; 2) the testing did not include straight-line sprinting; 3) the reported values did not include data distribution; 4) the study reported only maximum speed without skating time or average speed; 5) the end of the sprint was defined by the point the player stopped sprinting; 6) the measurement was made with a stopwatch; and, 7) the study had high bias estimation. The maximum speed test was not included due to the uncertain velocity conditions at beginning of testing distance. The bias estimation was performed using the JBI (Joanna Briggs Institute) Critical Appraisal Checklist for Analytical Cross Sectional Studies (supplementary material 1).
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Brosh, Arieh, David Robertshaw, Yoav Aharoni, Zvi Holzer, Mario Gutman, and Amichai Arieli. Estimation of Energy Expenditure of Free Living and Growing Domesticated Ruminants by Heart Rate Measurement. United States Department of Agriculture, April 2002. http://dx.doi.org/10.32747/2002.7580685.bard.

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Research objectives were: 1) To study the effect of diet energy density, level of exercise, thermal conditions and reproductive state on cardiovascular function as it relates to oxygen (O2) mobilization. 2) To validate the use of heart rate (HR) to predict energy expenditure (EE) of ruminants, by measuring and calculating the energy balance components at different productive and reproductive states. 3) To validate the use of HR to identify changes in the metabolizable energy (ME) and ME intake (MEI) of grazing ruminants. Background: The development of an effective method for the measurement of EE is essential for understanding the management of both grazing and confined feedlot animals. The use of HR as a method of estimating EE in free-ranging large ruminants has been limited by the availability of suitable field monitoring equipment and by the absence of empirical understanding of the relationship between cardiac function and metabolic rate. Recent developments in microelectronics provide a good opportunity to use small HR devices to monitor free-range animals. The estimation of O2 uptake (VO2) of animals from their HR has to be based upon a consistent relationship between HR and VO2. The question as to whether, or to what extent, feeding level, environmental conditions and reproductive state affect such a relationship is still unanswered. Studies on the basic physiology of O2 mobilization (in USA) and field and feedlot-based investigations (in Israel) covered a , variety of conditions in order to investigate the possibilities of using HR to estimate EE. In USA the physiological studies conducted using animals with implanted flow probes, show that: I) although stroke volume decreases during intense exercise, VO2 per one heart beat per kgBW0.75 (O2 Pulse, O2P) actually increases and measurement of EE by HR and constant O2P may underestimate VO2unless the slope of the regression relating to heart rate and VO2 is also determined, 2) alterations in VO2 associated with the level of feeding and the effects of feeding itself have no effect on O2P, 3) both pregnancy and lactation may increase blood volume, especially lactation; but they have no effect on O2P, 4) ambient temperature in the range of 15 to 25°C in the resting animal has no effect on O2P, and 5) severe heat stress, induced by exercise, elevates body temperature to a sufficient extent that 14% of cardiac output may be required to dissipate the heat generated by exercise rather than for O2 transport. However, this is an unusual situation and its affect on EE estimation in a freely grazing animal, especially when heart rate is monitored over several days, is minor. In Israel three experiments were carried out in the hot summer to define changes in O2P attributable to changes in the time of day or In the heat load. The animals used were lambs and young calves in the growing phase and highly yielding dairy cows. In the growing animals the time of day, or the heat load, affected HR and VO2, but had no effect on O2P. On the other hand, the O2P measured in lactating cows was affected by the heat load; this is similar to the finding in the USA study of sheep. Energy balance trials were conducted to compare MEI recovery by the retained energy (RE) and by EE as measured by HR and O2P. The trial hypothesis was that if HR reliably estimated EE, the MEI proportion to (EE+RE) would not be significantly different from 1.0. Beef cows along a year of their reproductive cycle and growing lambs were used. The MEI recoveries of both trials were not significantly different from 1.0, 1.062+0.026 and 0.957+0.024 respectively. The cows' reproductive state did not affect the O2P, which is similar to the finding in the USA study. Pasture ME content and animal variables such as HR, VO2, O2P and EE of cows on grazing and in confinement were measured throughout three years under twenty-nine combinations of herbage quality and cows' reproductive state. In twelve grazing states, individual faecal output (FO) was measured and MEI was calculated. Regression analyses of the EE and RE dependent on MEI were highly significant (P<0.001). The predicted values of EE at zero intake (78 kcal/kgBW0.75), were similar to those estimated by NRC (1984). The EE at maintenance condition of the grazing cows (EE=MEI, 125 kcal/kgBW0.75) which are in the range of 96.1 to 125.5 as presented by NRC (1996 pp 6-7) for beef cows. Average daily HR and EE were significantly increased by lactation, P<0.001 and P<0.02 respectively. Grazing ME significantly increased HR and EE, P<0.001 and P<0.00l respectively. In contradiction to the finding in confined ewes and cows, the O2P of the grazing cows was significantly affected by the combined treatments (P<0.00l ); this effect was significantly related to the diet ME (P<0.00l ) and consequently to the MEI (P<0.03). Grazing significantly increased O2P compared to confinement. So, when EE of grazing animals during a certain season of the year is estimated using the HR method, the O2P must be re measured whenever grazing ME changes. A high correlation (R2>0.96) of group average EE and of HR dependency on MEI was also found in confined cows, which were fed six different diets and in growing lambs on three diets. In conclusion, the studies conducted in USA and in Israel investigated in depth the physiological mechanisms of cardiovascular and O2 mobilization, and went on to investigate a wide variety of ruminant species, ages, reproductive states, diets ME, time of intake and time of day, and compared these variables under grazing and confinement conditions. From these combined studies we can conclude that EE can be determined from HR measurements during several days, multiplied by O2P measured over a short period of time (10-15 min). The study showed that RE could be determined during the growing phase without slaughtering. In the near future the development microelectronic devices will enable wide use of the HR method to determine EE and energy balance. It will open new scopes of physiological and agricultural research with minimizes strain on animals. The method also has a high potential as a tool for herd management.
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Hodgdon, James A., and Karl Friedl. Development of the DoD Body Composition Estimation Equations. Fort Belvoir, VA: Defense Technical Information Center, September 1999. http://dx.doi.org/10.21236/ada370158.

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Cloos, John J., and James D. McCullough. New Accounting Systems and Their Effects on DoD Cost Estimating. Fort Belvoir, VA: Defense Technical Information Center, December 1989. http://dx.doi.org/10.21236/ada218247.

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Turner, Daniel Z. An overview of the gradient-based local DIC formulation for motion estimation in DICe. Office of Scientific and Technical Information (OSTI), July 2016. http://dx.doi.org/10.2172/1561808.

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Wolff, Patrick, Brett DeGregorio, John Wilson, Jennifer Mortensen, and Jinelle Sperry. Estimating the density of secretive, at-risk snake species on DoD installations using an innovative approach : IDEASS. Engineer Research and Development Center (U.S.), October 2020. http://dx.doi.org/10.21079/11681/38319.

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NARYKOVA, N. A., S. V. KHATAGOVA, and Yu R. PEREPELITSYNA. PEJORATIVE WORDS IN GERMAN MASS-MEDIA IN NOMINATIONS OF POLITICIANS. Science and Innovation Center Publishing House, April 2022. http://dx.doi.org/10.12731/2077-1770-2021-14-1-3-57-68.

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One of the main functions of mass media is influence on public opinion. So emotionally-painted lexical means are widely used in mass media in relation to leading politicians who are the centre of political arena. They are exposed to the frequent criticism, a negative estimation. The present article is devoted to the consideration of pejorative lexicon which is applied in nominations for heads of states. An empirical material of research were electronic newspapers and editions: Der Spiegel, Die Zeit, Sueddeutsche Zeitung, Der Tagesspiegel, taz, Die Welt, Gegenblende. As the basic methods of research are the following: the componental analysis, the lexico-semantic analysis, the stylistic analysis. The result of research revealed, that in German mass media there is a significant amount of persons names pejorative colouring. They express censure, disrespect, sneer, hatred, antipathy, condemnation, mistrust and so on. There main word-formations for persons nominations are composition, a derivation with using of suffixes and subsuffixes, attributive word-combinations, metaphorically-metonymical way. The materials of the research work can be used in the course of learning German language, at the practical training in oral speech, and also in the course of lexicology, general and aspect lexicography.
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Downing, W. Logan, Howell Li, William T. Morgan, Cassandra McKee, and Darcy M. Bullock. Using Probe Data Analytics for Assessing Freeway Speed Reductions during Rain Events. Purdue University, 2021. http://dx.doi.org/10.5703/1288284317350.

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Rain impacts roadways such as wet pavement, standing water, decreased visibility, and wind gusts and can lead to hazardous driving conditions. This study investigates the use of high fidelity Doppler data at 1 km spatial and 2-minute temporal resolution in combination with commercial probe speed data on freeways. Segment-based space-mean speeds were used and drops in speeds during rainfall events of 5.5 mm/hour or greater over a one-month period on a section of four to six-lane interstate were assessed. Speed reductions were evaluated as a time series over a 1-hour window with the rain data. Three interpolation methods for estimating rainfall rates were tested and seven metrics were developed for the analysis. The study found sharp drops in speed of more than 40 mph occurred at estimated rainfall rates of 30 mm/hour or greater, but the drops did not become more severe beyond this threshold. The average time of first detected rainfall to impacting speeds was 17 minutes. The bilinear method detected the greatest number of events during the 1-month period, with the most conservative rate of predicted rainfall. The range of rainfall intensities were estimated between 7.5 to 106 mm/hour for the 39 events. This range was much greater than the heavy rainfall categorization at 16 mm/hour in previous studies reported in the literature. The bilinear interpolation method for Doppler data is recommended because it detected the greatest number of events and had the longest rain duration and lowest estimated maximum rainfall out of three methods tested, suggesting the method balanced awareness of the weather conditions around the roadway with isolated, localized rain intensities.
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Engel, Bernard, Yael Edan, James Simon, Hanoch Pasternak, and Shimon Edelman. Neural Networks for Quality Sorting of Agricultural Produce. United States Department of Agriculture, July 1996. http://dx.doi.org/10.32747/1996.7613033.bard.

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The objectives of this project were to develop procedures and models, based on neural networks, for quality sorting of agricultural produce. Two research teams, one in Purdue University and the other in Israel, coordinated their research efforts on different aspects of each objective utilizing both melons and tomatoes as case studies. At Purdue: An expert system was developed to measure variances in human grading. Data were acquired from eight sensors: vision, two firmness sensors (destructive and nondestructive), chlorophyll from fluorescence, color sensor, electronic sniffer for odor detection, refractometer and a scale (mass). Data were analyzed and provided input for five classification models. Chlorophyll from fluorescence was found to give the best estimation for ripeness stage while the combination of machine vision and firmness from impact performed best for quality sorting. A new algorithm was developed to estimate and minimize training size for supervised classification. A new criteria was established to choose a training set such that a recurrent auto-associative memory neural network is stabilized. Moreover, this method provides for rapid and accurate updating of the classifier over growing seasons, production environments and cultivars. Different classification approaches (parametric and non-parametric) for grading were examined. Statistical methods were found to be as accurate as neural networks in grading. Classification models by voting did not enhance the classification significantly. A hybrid model that incorporated heuristic rules and either a numerical classifier or neural network was found to be superior in classification accuracy with half the required processing of solely the numerical classifier or neural network. In Israel: A multi-sensing approach utilizing non-destructive sensors was developed. Shape, color, stem identification, surface defects and bruises were measured using a color image processing system. Flavor parameters (sugar, acidity, volatiles) and ripeness were measured using a near-infrared system and an electronic sniffer. Mechanical properties were measured using three sensors: drop impact, resonance frequency and cyclic deformation. Classification algorithms for quality sorting of fruit based on multi-sensory data were developed and implemented. The algorithms included a dynamic artificial neural network, a back propagation neural network and multiple linear regression. Results indicated that classification based on multiple sensors may be applied in real-time sorting and can improve overall classification. Advanced image processing algorithms were developed for shape determination, bruise and stem identification and general color and color homogeneity. An unsupervised method was developed to extract necessary vision features. The primary advantage of the algorithms developed is their ability to learn to determine the visual quality of almost any fruit or vegetable with no need for specific modification and no a-priori knowledge. Moreover, since there is no assumption as to the type of blemish to be characterized, the algorithm is capable of distinguishing between stems and bruises. This enables sorting of fruit without knowing the fruits' orientation. A new algorithm for on-line clustering of data was developed. The algorithm's adaptability is designed to overcome some of the difficulties encountered when incrementally clustering sparse data and preserves information even with memory constraints. Large quantities of data (many images) of high dimensionality (due to multiple sensors) and new information arriving incrementally (a function of the temporal dynamics of any natural process) can now be processed. Furhermore, since the learning is done on-line, it can be implemented in real-time. The methodology developed was tested to determine external quality of tomatoes based on visual information. An improved model for color sorting which is stable and does not require recalibration for each season was developed for color determination. Excellent classification results were obtained for both color and firmness classification. Results indicted that maturity classification can be obtained using a drop-impact and a vision sensor in order to predict the storability and marketing of harvested fruits. In conclusion: We have been able to define quantitatively the critical parameters in the quality sorting and grading of both fresh market cantaloupes and tomatoes. We have been able to accomplish this using nondestructive measurements and in a manner consistent with expert human grading and in accordance with market acceptance. This research constructed and used large databases of both commodities, for comparative evaluation and optimization of expert system, statistical and/or neural network models. The models developed in this research were successfully tested, and should be applicable to a wide range of other fruits and vegetables. These findings are valuable for the development of on-line grading and sorting of agricultural produce through the incorporation of multiple measurement inputs that rapidly define quality in an automated manner, and in a manner consistent with the human graders and inspectors.
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