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Journal articles on the topic "Plot errors"
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Hernández-Stefanoni, José, Gabriela Reyes-Palomeque, Miguel Castillo-Santiago, Stephanie George-Chacón, Astrid Huechacona-Ruiz, Fernando Tun-Dzul, Dinosca Rondon-Rivera, and Juan Dupuy. "Effects of Sample Plot Size and GPS Location Errors on Aboveground Biomass Estimates from LiDAR in Tropical Dry Forests." Remote Sensing 10, no. 10 (October 2, 2018): 1586. http://dx.doi.org/10.3390/rs10101586.
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Accurate estimates of above ground biomass (AGB) are needed for monitoring carbon in tropical forests. LiDAR data can provide precise AGB estimations because it can capture the horizontal and vertical structure of vegetation. However, the accuracy of AGB estimations from LiDAR is affected by a co-registration error between LiDAR data and field plots resulting in spatial discrepancies between LiDAR and field plot data. Here, we evaluated the impacts of plot location error and plot size on the accuracy of AGB estimations predicted from LiDAR data in two types of tropical dry forests in Yucatán, México. We sampled woody plants of three size classes in 29 nested plots (80 m2, 400 m2 and 1000 m2) in a semi-deciduous forest (Kiuic) and 28 plots in a semi-evergreen forest (FCP) and estimated AGB using local allometric equations. We calculated several LiDAR metrics from airborne data and used a Monte Carlo simulation approach to assess the influence of plot location errors (2 to 10 m) and plot size on ABG estimations from LiDAR using regression analysis. Our results showed that the precision of AGB estimations improved as plot size increased from 80 m2 to 1000 m2 (R2 = 0.33 to 0.75 and 0.23 to 0.67 for Kiuic and FCP respectively). We also found that increasing GPS location errors resulted in higher AGB estimation errors, especially in the smallest sample plots. In contrast, the largest plots showed consistently lower estimation errors that varied little with plot location error. We conclude that larger plots are less affected by co-registration error and vegetation conditions, highlighting the importance of selecting an appropriate plot size for field forest inventories used for estimating biomass.
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Gobakken, Terje, and Erik Næsset. "Assessing effects of positioning errors and sample plot size on biophysical stand properties derived from airborne laser scanner data." Canadian Journal of Forest Research 39, no. 5 (May 2009): 1036–52. http://dx.doi.org/10.1139/x09-025.
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Canopy height distributions were created from small-footprint airborne laser scanner data with an average sampling density of 1.1 points·m–2 collected over 132 sample plots and 61 stands. Field measurements of each plot were carried out within two concentric circles (200 m2 and 300 or 400 m2). The plot positions were altered randomly with Monte Carlo simulations. For various metrics derived from the canopy height distributions, the mean and the standard deviation (SD) of the differences between incorrect plot positions and ground-truth positions were compared. In general, SD was smaller for large field plots than for small plots, and the variation in SD among the Monte Carlo repetitions was smaller for large sample plots. The combined effects of field plot size and sample plot position error on the accuracy of mean tree height (hL), stand basal area (G), and stand volume (V) predicted at stand level using a two-stage procedure combining field training data and laser data were assessed. Standard deviation of the differences between predicted and observed hL was quite stable and of similar size for position errors up to 5 m. However, for G and V the influence of plot position error was more pronounced.
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Behrens, John T., William A. Stock, and Catherine Sedgwick. "Judgment Errors in Elementary Box-Plot Displays." Communications in Statistics - Simulation and Computation 19, no. 1 (January 1990): 245–62. http://dx.doi.org/10.1080/03610919008812855.
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Schwemmle, Robin, Dominic Demand, and Markus Weiler. "Technical note: Diagnostic efficiency – specific evaluation of model performance." Hydrology and Earth System Sciences 25, no. 4 (April 22, 2021): 2187–98. http://dx.doi.org/10.5194/hess-25-2187-2021.
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Abstract. A better understanding of the reasons why hydrological model performance is unsatisfying represents a crucial part of meaningful model evaluation. However, current evaluation efforts are mostly based on aggregated efficiency measures such as Kling–Gupta efficiency (KGE) or Nash–Sutcliffe efficiency (NSE). These aggregated measures provide a relative gradation of model performance. Especially in the case of a weak model performance it is important to identify the different errors which may have caused such unsatisfactory predictions. These errors may originate from the model parameters, the model structure, and/or the input data. In order to provide more insight, we define three types of errors which may be related to their source: constant error (e.g. caused by consistent input data error such as precipitation), dynamic error (e.g. structural model errors such as a deficient storage routine) and timing error (e.g. caused by input data errors or deficient model routines/parameters). Based on these types of errors, we propose the novel diagnostic efficiency (DE) measure, which accounts for these three error types. The disaggregation of DE into its three metric terms can be visualized in a plain radial space using diagnostic polar plots. A major advantage of this visualization technique is that error contributions can be clearly differentiated. In order to provide a proof of concept, we first generated time series artificially with the three different error types (i.e. simulations are surrogated by manipulating observations). By computing DE and the related diagnostic polar plots for the reproduced errors, we could then supply evidence for the concept. Finally, we tested the applicability of our approach for a modelling example. For a particular catchment, we compared streamflow simulations realized with different parameter sets to the observed streamflow. For this modelling example, the diagnostic polar plot suggests that dynamic errors explain the overall error to a large extent. The proposed evaluation approach provides a diagnostic tool for model developers and model users and the diagnostic polar plot facilitates interpretation of the proposed performance measure as well as a relative gradation of model performance similar to the well-established efficiency measures in hydrology.
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Fortin, Mathieu, Josianne DeBlois, Sylvain Bernier, and Georges Blais. "Mise au point d'un tarif de cubage général pour les forêts québécoises : une approche pour mieux évaluer l'incertitude associée aux prévisions." Forestry Chronicle 83, no. 5 (September 1, 2007): 754–65. http://dx.doi.org/10.5558/tfc83754-5.
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Merchantable volume assessment is of prime importance in forest management and for the estimation of wood production in Quebec Crown forests. Currently, this assessment is undertaken at the individual stem level according to a statistical model commonly identified as the Perron general stock table. This polynomial model is based on tree diameter at breast height and tree height. However, the mathematical model form and the method used to calibrate it do not enable a correct and detailed assessment of the uncertainty associated with volume assessments. This study describes a new model which, accounts for errors associated with the use of estimated height in volume forecasts and also limits the propogation of errors to sample plot and cruise line. Random effects have been specified in the model in order to take into account spatial correlation between observations made at the sample plot and cruise line level. Results indicate sample plot and cruise line random errors constitute components of model error, which individually range from 2 % to 4 % of volume assessment. Consequently, the basic premise that errors associated with volume assessment of individual stems are compensated by volume summations at the sample plot level is not valid. Key words: mixed model, random effect, error propagation, variance
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SINGH, M., and M. PALA. "Use of covariance structures for temporal errors in the analysis of a three-course wheat rotation and tillage trial." Journal of Agricultural Science 142, no. 2 (April 2004): 193–201. http://dx.doi.org/10.1017/s0021859604004174.
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Crop rotation serves as a mechanism for developing sustainable crop production systems. Crop-rotation trials are used to identify agronomic input factors suitable for use in a cropping system. In crop-rotation trials, experimental errors within the same plot over time are correlated. The form of the covariance structure of the plot errors may be specific to the data from a rotation trial, but is unknown and is generally assumed. Statistical analyses are usually based on the assumption that plot errors are independent, or have constant covariance. An experiment was conducted using wheat-based, three-course rotations containing tillage treatment subplots over 12 years at ICARDA's experimental station at Tel Hadya, a moderately dry area in northern Syria. This study examined several covariance structures for temporal errors arising over the rotation plots and tillage subplots, in order to model wheat yield data. Eighteen covariance structures were examined, and the best pair was selected using the Akaike Information Criterion. The best pair comprised first-order autocorrelation and homogeneous variance for temporal errors in rotation plots, and uniform correlation with heterogeneous variances for temporal errors in tillage subplots. Using the 12 years of data obtained for wheat yield and the best pair of covariance structures, the tillage and rotation effects were found to be statistically significant and to have significant interactions with the cycle of rotation. The precision of the means calculated differed from those calculated using a control structure based on homogeneous error variances and constant correlation. The cumulative yield build-up over time differed significantly over the rotations and the tillage methods. An increasing yield trend was observed for the bread wheat rotation, while a yield decline was observed in durum wheat when the rotation was repeated. When evaluating the effects of input factors in crop rotations, we therefore recommend that the covariance structures be examined and that a suitably chosen structure be used.
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Mauro, F., R. Valbuena, J. A. Manzanera, and A. García-Abril. "Influence of Global Navigation Satellite System errors in positioning inventory plots for tree-height distribution studiesThis article is one of a selection of papers from Extending Forest Inventory and Monitoring over Space and Time." Canadian Journal of Forest Research 41, no. 1 (January 2011): 11–23. http://dx.doi.org/10.1139/x10-164.
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Validation of predictive models in remote sensing requires a good coregistration of field and sensor data sets. However, previous research has demonstrated that Global Navigation Satellite System survey techniques often produce large positioning errors when applied to areas under forest canopies. In this article, we present a repeatable methodology for analyzing the effect of such errors when validating models that predict tree-height distributions from LiDAR data sets. The method is based on conditional probability theory applied to error positioning and includes an error assessment of the surveying technique. A technical criterion for selecting the plot radius that avoids significant effects of positioning errors was proposed. We demonstrated that for a plot radius greater than 10 m, the effects of positioning errors introduced by a phase-differential device were insignificant when studying forest tree-height distributions.
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Van Deusen, Paul C. "Forest inventory estimation with mapped plots." Canadian Journal of Forest Research 34, no. 2 (February 1, 2004): 493–97. http://dx.doi.org/10.1139/x03-209.
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Procedures are developed for estimating means and variances with a mapped-plot design. The focus is on fixed-area plots, and simulations are used to validate the proposed estimators. The mapped-plot estimators for means and variances are compared with simple random sampling estimators that utilize only full plots. As expected, the mapped-plot estimates have smaller mean squared errors than the simple random sampling estimates. The theory for fixed-area plots is easy to apply, although additional work is required to map plots in the field. Corresponding theory for variable plots is developed but not tested with simulations. The difficulty of applying these methods to variable plots is greater, but not prohibitive.
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Sabor, Alexia A., Volker C. Radeloff, Ronald E. McRoberts, Murray Clayton, and Susan I. Stewart. "Adding uncertainty to forest inventory plot locations: effects on analyses using geospatial data." Canadian Journal of Forest Research 37, no. 11 (November 2007): 2313–25. http://dx.doi.org/10.1139/x07-067.
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The Forest Inventory and Analysis (FIA) program of the USDA Forest Service alters plot locations before releasing data to the public to ensure landowner confidentiality and sample integrity, but using data with altered plot locations in conjunction with other spatially explicit data layers produces analytical results with unknown amounts of error. We calculated the potential error from using altered location data in combination with other data layers that varied in mean map unit size. The incidence of errors associated with the use of altered plot locations exhibited a strong inverse relationship to the mean map unit size of the other data sets used in the analyses. For a 30 m × 30 m resolution land cover map, plot misclassification rates ranged from 32% to 66%, whereas only 1%–10% of plots were misclassified for ecological subsection data (mean polygon size 9067 km2). Housing density data derived from the US Decennial Census (mean polygon size = 5.7 km2) represented an intermediate condition, with 5%–70% of data points misclassified when altered plot locations were used. These analyses demonstrate the impacts of altering FIA plot locations and represent an important step toward making the FIA database more helpful to a broad variety of end users.
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AKIMOTO, Naoshige, Hisako HANAKUMA, and Keiichiro HOZUMI. "Errors in acid-base titration using Gran's plot method." Analytical Sciences 3, no. 6 (1987): 515–19. http://dx.doi.org/10.2116/analsci.3.515.
Full textDissertations / Theses on the topic "Plot errors"
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Rapp, John Francis 1963. "Error assessment of the revised universal soil loss equation using natural runoff plot data." Thesis, The University of Arizona, 1994. http://hdl.handle.net/10150/291699.
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The error associated with the Revised Universal Soil Loss Equation (RUSLE) was determined by utilizing data from 21 U.S. sites representing 1704 years of measurements from 206 plots. RUSLE estimates were compared to the measured values for each year and the average value for each plot duration. The model efficiency coefficient on an annual basis was (.58) and on an average annual basis was (.73). The RUSLE was consistent with a previous study of the USLE which tended to over predict on plots with low erosion rates and under predict on plots with high erosion rates. Also the Topographic Factor (LS) value and the Cover and Management Factor (C) value had the most influence on model efficiency. The basis for this study was to compare the RUSLE with the USLE and to compare RUSLE simulations with observed data that was not a part of its critical development.
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Padilla, Miguel A. "Type I error rates for the Kenward-Roger adjusted degree of freedom F-test for a split-plot design with missing values." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0010811.
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Slui, Benjamin Thomas. "The effect of plot co-registration error on the strength of regression between LiDAR canopy metrics and total standing volume in a Pinus radiata forest." Thesis, University of Canterbury. School of Forestry, 2014. http://hdl.handle.net/10092/10460.
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Background: The objective of this study was to verify the effect that plot locational errors, termed plot co-registration errors, have on the strength of regression between LiDAR canopy metrics and the measured total standing volume (TSV) of plots in a Pinus radiata forest.
Methods: A 737 hectare plantation of mature Pinus radiata located in Northern Hawkes Bay was selected for the study. This forest had been measured in a pre-harvest inventory and had aerial LiDAR assessment. The location of plots was verified using a survey-grade GPS. Least square linear regression models were developed to predict TSV from LiDAR canopy metrics for a sample of 204 plots. The regression strength, accuracy and bias was compared for models developed using either the actual (verified) or the incorrect (intended) locations for these plots. The change to the LiDAR canopy metrics after the plot co-registration errors was also established.
Results: The plot co-registration error in the sample ranged from 0.7 m to 70.3 m, with an average linear spatial error of 10.6 m. The plot co-registration errors substantially reduced the strength of regression between LiDAR canopy metrics and TSV, as the model developed from the actual plot locations had an R2 of 44%, while the model developed from the incorrect plot locations had an R2 of 19%. The greatest reductions in model strength occurred when there was less than a 60% overlap between the plots defined by correct and incorrect locations. Higher plot co-registration errors also caused significant changes to the height and density LiDAR canopy metrics that were used in the regression models. The lower percentile elevation LiDAR metrics were more sensitive to plot co- registration errors, compared to higher percentile metrics.
Conclusion: Plot co-registration errors have a significant effect on the strength of regressions formed between TSV and LiDAR canopy metrics. This indicates that accurate measurements of plot locations are necessary to fully utilise LiDAR for inventory purposes in forests of Pinus radiata.
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Ozol-Godfrey, Ayca. "Understanding Scaled Prediction Variance Using Graphical Methods for Model Robustness, Measurement Error and Generalized Linear Models for Response Surface Designs." Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/30185.
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Graphical summaries are becoming important tools for evaluating designs. The need to compare designs in term of their prediction variance properties advanced this development. A recent graphical tool, the Fraction of Design Space plot, is useful to calculate the fraction of the design space where the scaled prediction variance (SPV) is less than or equal to a given value. In this dissertation we adapt FDS plots, to study three specific design problems: robustness to model assumptions, robustness to measurement error and design properties for generalized linear models (GLM). This dissertation presents a graphical method for examining design robustness related to the SPV values using FDS plots by comparing designs across a number of potential models in a pre-specified model space. Scaling the FDS curves by the G-optimal bounds of each model helps compare designs on the same model scale. FDS plots are also adapted for comparing designs under the GLM framework. Since parameter estimates need to be specified, robustness to parameter misspecification is incorporated into the plots. Binomial and Poisson examples are used to study several scenarios. The third section involves a special type of response surface designs, mixture experiments, and deals with adapting FDS plots for two types of measurement error which can appear due to inaccurate measurements of the individual mixture component amounts. The last part of the dissertation covers mixture experiments for the GLM case and examines prediction properties of mixture designs using the adapted FDS plots.Ph. D.
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Giosa, Francesca. "I test d'ipotesi e la loro declinazione in ambito medico." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/15992/.
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Una domanda di rilevante interesse in ambito medico e in particolare nell'ambito della ricerca medica è: avendo a disposizione un certo numero di farmaci quale di questi è più efficace? E' chiaro quanto sia importante conoscere l'efficacia di un farmaco prima di somministrarlo e la statistica medica con lo strumento statistico comunemente chiamato Test d'ipotesi si occupa di rispondere a queste domande e di limitare il più possibile gli errori di valutazione che si possono commettere. Lo scopo della mia tesi è spiegare l'utilizzo dei test d'ipotesi e in particolare di analizzare il confronto tra due e più popolazioni (gaussiane e non), ponendo attenzione alle varie possibilità di impostazione del problema a seconda delle ipotesi che vengono di volta in volta soddisfatte.
Infatti a seconda del disegno sperimentale del problema che si vuole trattare, molto spesso si fa un uso diverso della stessa tecnica e la maggior parte degli errori nella letteratura biomedica riguarda proprio errori basilari nel disegno sperimentale, come per esempio una errata procedura di randomizzazione o l'omissione del gruppo di controllo, oppure l'utilizzo non appropriato del test t per confronti multipli. Pertanto è bene fare attenzione alle diverse possibilità e capire quali sono le più adatte nei vari casi.
Per questo motivo il percorso seguito nella mia tesi è basato sulla importanza della adeguatezza del modello utilizzato e della verifica delle ipotesi che permettono di utilizzare un metodo di risoluzione piuttosto che un altro. Inoltre ho presentato un esempio tratto da una situazione reale, con dati forniti dall'istituto per lo scompenso cardiaco di Bologna. Questo esempio è volto a mettere in evidenza l'importanza della adeguatezza del modello e i problemi pratici in cui si può incorrere.
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Urbonavičius, Svajūnas. "Brandžių medynų tūrio nustatymo metodų tikslumo tyrimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2007. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2007~D_20070816_154623-53899.
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Darbo objektas - Telšių miškų urėdijos, Žarėnų girininkijos brandūs mišrūs eglės su lapuočiais medynai. Darbo tikslas – nustatyti dažniausiai miško inventorizacijos praktikoje naudojamų tūrio nustatymo metodų tikslumą ir išanalizuoti jį lemiančias priežastis. Darbo metodai – tūrio paklaidų, gautų lyginant medienos tūrius, nustatytus pagal sklypinės miškų inventorizacijos ir biržių atrėžimo ir įvertinimo duomenimis su pagamintos medienos duomenimis, analizė. Darbo rezultatai. Atlikus tų pačių medynų tūrio įvertinimą įvairiais metodais ir visų matavimo rezultatų analizę, paaiškėjo, kad sklypinė miškų inventorizacija tūrį Žarėnų miško masyve vidutiniškai didina 10,2 %, lyginant su ištisiniu medžių apmatavimo metodu. Įvertinę brandžių medynų tūrį, pagal pagamintą medienos produkciją, gauti rezultatai mišriuose eglės medynuose svyruoja nuo -3,0 % iki 9,9 %, bendra paklaida yra 4,9 % didesnė lyginant su ištisiniu medžių matavimo metodu. Raktažodžiai: Sklypinė miškų inventorizacija, ištisinis medžių matavimas, atrankinis medžių matavimas, medynų tūris, paklaidos.OBJECT OF RESEARCH-mature mixed spruce - broadlives forests in Telšiai forest enterprise, Žarėnai forest. AIM OF RESEARCH- to determine the accuracy of most frequently applied methods to rate the volume in the practice of forest inventory and to analyze the causes that influence it. METHODS OF RESEARCH- the analysis of volume errors, got by comparing timber volumes, set according to the data of inventory of forest plots and their delimitation and the data of their evaluation with the data of manufactured timber acceptance. RESULTS OF RESEARCH-after having done the evaluation of the same timber volume using different methods and the analysis of all the results of measurement, it emerged that stand-wise forest inventory increases the volume in the array of Žarėnai forests by 10.2% when compared to the continuous forest measurement. After evaluating the volume of mature trees according to the made timber production the results in mixed fir trees range from -3,0 % to 9,9 %, a common error 4,9 % better compared to the continuous forest measurement.
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Vyas, Saurabh, and Venkata Dinesh Raju Jonnalagadda. "Modelling of Automotive Suspension Damper." Thesis, KTH, Fordonsdynamik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-293498.
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A hydraulic damper plays an important role in tuning the handling and comfort characteristicsof a vehicle. Tuning and selecting a damper based on subjective evaluation, by considering theopinions of various users, would be an inefficient method since the comfort requirements of usersvary a lot. Instead, mathematical models of damper and simulation of these models in variousoperating conditions are preferred to standardize the tuning procedure, quantify the comfortlevels and reduce cost of testing. This would require a model, which is good enough to capture thebehaviour of damper in various operating and extreme conditions.The Force-Velocity (FV) curve is one of the most widely used model of a damper. This curve isimplemented either as an equation or as a look-up table. It is a plot between the maximum forceat each peak velocity point. There are certain dynamic phenomena like hysteresis and dependencyon the displacement of damper, which cannot be captured with a FV curve model, but are requiredfor better understanding of the vehicle behaviour.This thesis was conducted in cooperation with Volvo Cars with an aim to improve the existingdamper model which is a Force-Velocity curve. This work focuses on developing a damper model,which is complex enough to capture the phenomena discussed above and simple enough to beimplemented in real time simulations. Also, the thesis aims to establish a standard method toparameterise the damper model and generate the Force-Velocity curve from the tests performedon the damper test rig. A test matrix which includes the standard tests for parameterising andthe extreme test cases for the validation of the developed model will be developed. The final focusis to implement the damper model in a multi body simulation (MBS) software.The master thesis starts with an introduction, where the background for the project is described and then the thesis goals are set. It is followed by a literature review in which fewadvanced damper models are discussed in brief. Then, a step-by-step process of developing thedamper model is discussed along with few more possible options. Later, the construction of a testmatrix is discussed in detail followed by the parameter identification process. Next, the validationof the developed damper model is discussed using the test data from Volvo Hällered ProvingGround (HPG). After validation, implementation of the model in VI CarRealTime and Adams Caralong with the results are presented. Finally the thesis is concluded and the recommendations forfuture work are made on further improving the model.En hydraulisk stötdämpare spelar en viktig roll för att fordonets hantering och komfort. Attjustera och välja en stötdämpare baserat på subjektiv utvärdering, genom att beakta olika användares åsikter, skulle vara en ineffektiv metod eftersom användarnas komfortkrav varierarmycket. Istället föredras matematiska modeller av stötdämpare och simulering av dessa modellerunder olika driftsförhållanden för att standardisera inställningsförfarandet, kvantifiera komfortnivåerna och minska testkostnaden. Detta skulle kräva en modell som är tillräckligt bra för attfånga upp stötdämparens beteende under olika drifts- och extrema förhållanden.Force-Velocity (FV) -kurvan är en av de mest använda stötdämparmodellerna. Denna kurvaimplementeras antingen som en ekvation eller som en uppslagstabell. Det är ett diagram somredovisar den maximala kraften vid varje maxhastighetspunkt. Det finns vissa dynamiskafenomen som hysteres och beroende av stötdämparens förskjutning, som inte kan fångas med enFV-kurvmodell, men som krävs för att bättre förstå fordonets beteende.Denna avhandling genomfördes i samarbete med Volvo Cars i syfte att förbättra den befintligastötdämparmodellen som är en Force-Velocity-kurva. Detta arbete fokuserar på att utveckla enstötdämparmodell, som är tillräckligt komplex för att fånga upp de fenomen som diskuteratsovan och tillräckligt enkel för att implementeras i realtidssimuleringar. Avhandlingen syftarockså till att upprätta en standardmetod för att parametrisera spjällmodellen och generera ForceVelocity-kurvan från de test som utförts på stötdämpartestriggen. En testmatris som innehållerstandardtest för parametrisering och extrema testfall för validering av den utvecklade modellenkommer att utvecklas. Det sista fokuset är att implementera stötdämparmodellen i en multi-bodysimulation (MBS) programvara.Examensarbetet inleds med en introduktion, där bakgrunden för projektet beskrivs ochdärefter definieras målen med arbetet. Det följs av en litteraturöversikt där några avanceradestötdämparmodeller diskuteras i korthet. Därefter diskuteras en steg-för-steg-process för attutveckla stötdämparmodeller tillsammans med några fler möjliga alternativ. Senare diskuteraskonstruktionen av en testmatris i detalj följt av parameteridentifieringsprocessen. Därefterdiskuteras valideringen av den utvecklade stötdämparmodellen med hjälp av testdata från VolvoHällered Proving Ground (HPG). Efter validering presenteras implementeringen av modellen iVI CarRealTime och Adams Car tillsammans med resultaten. Slutligen avslutas rapporten medslutsatser från arbetet och rekommendationer för framtida arbete görs för att ytterligare förbättramodellen.
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Ayed, Mohamed. "Automatisation de la saisie graphique de schémas logiques sur APPLICON." Paris 11, 1985. http://www.theses.fr/1985PA112190.
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Ce travail présente des améliorations du mode opératoire de la saisie graphique d’un schéma dur le système APPLICON. Les buts essentiels de la méthode proposée sont: - minimisation des étapes ‘manuelles’; - vérification automatique des erreurs pouvant être commises, et qui sont difficilement détectables ; - automatisation des étapes pouvant être des sources d’erreurs; - obtention d’une «Dev-list» correcte : qui traduit correctement le schéma correspondant.
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ZIAO, MENG-PING, and 蕭夢萍. "Combined analysis of two split-split plot design in randomized block layout with correlated errors and unequal number of sub-subtreatment levels." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/48715837015769318091.
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Obenauff, Alexander. "A progressive learning method for classification of manufacturing errors based on machine data." Master's thesis, 2019. http://hdl.handle.net/10362/76579.
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Dissertation presented as the partial requirement for obtaining a Master's degree in Data Science and Advanced AnalyticsManufacturing companies face significant market pressure in today’s globalised world. Fierce global competition and product individualisation mean that production systems require continuous optimisation. This means that automation, flexibility and efficiency have all become vital elements for manufacturers. In this paper, a method based on incremental classification used for manufacturing errors is presented. The analysis and classification focus on data of binary form collected from a machine control unit during manufacturing operation in real time. Various methods that can learn from data incrementally and autonomously are to be applied. The training starts with the least amount of data possible and other important steps like data preprocessing are reviewed under the aspect of incremental learning.
Books on the topic "Plot errors"
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Langley, R. H. The Doctor Who error finder: Plot, continuity, and production mistakes in the television series and films. Jefferson, N C: McFarland & Co., 2005.
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Willem W. S. Van Hees. A comparison of two estimates of standard error for a ratio-of-means estimator for a mapped-plot sample design in Southeast Alaska. Portland, OR: U.S. Dept. of Agriculture, Forest Service, Pacific Northwest Research Station, 2002.
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McGown, Jill. Plots and Errors: (Detective Chief Inspector Lloyd & Judy Hill Mysteries). Fawcett, 2000.
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Desiere, Sam, and Dean Jolliffe. Land Productivity and Plot Size: Is Measurement Error Driving the Inverse Relationship? World Bank, Washington, DC, 2017. http://dx.doi.org/10.1596/1813-9450-8134.
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Desiere, Sam, and Dean Jolliffe. Land Productivity and Plot Size: Is Measurement Error Driving the Inverse Relationship? Elsevier, 2017. http://dx.doi.org/10.1596/28786.
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Ślusarski, Marek. Metody i modele oceny jakości danych przestrzennych. Publishing House of the University of Agriculture in Krakow, 2017. http://dx.doi.org/10.15576/978-83-66602-30-4.
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The quality of data collected in official spatial databases is crucial in making strategic decisions as well as in the implementation of planning and design works. Awareness of the level of the quality of these data is also important for individual users of official spatial data. The author presents methods and models of description and evaluation of the quality of spatial data collected in public registers. Data describing the space in the highest degree of detail, which are collected in three databases: land and buildings registry (EGiB), geodetic registry of the land infrastructure network (GESUT) and in database of topographic objects (BDOT500) were analyzed. The results of the research concerned selected aspects of activities in terms of the spatial data quality. These activities include: the assessment of the accuracy of data collected in official spatial databases; determination of the uncertainty of the area of registry parcels, analysis of the risk of damage to the underground infrastructure network due to the quality of spatial data, construction of the quality model of data collected in official databases and visualization of the phenomenon of uncertainty in spatial data. The evaluation of the accuracy of data collected in official, large-scale spatial databases was based on a representative sample of data. The test sample was a set of deviations of coordinates with three variables dX, dY and Dl – deviations from the X and Y coordinates and the length of the point offset vector of the test sample in relation to its position recognized as a faultless. The compatibility of empirical data accuracy distributions with models (theoretical distributions of random variables) was investigated and also the accuracy of the spatial data has been assessed by means of the methods resistant to the outliers. In the process of determination of the accuracy of spatial data collected in public registers, the author’s solution was used – resistant method of the relative frequency. Weight functions, which modify (to varying degree) the sizes of the vectors Dl – the lengths of the points offset vector of the test sample in relation to their position recognized as a faultless were proposed. From the scope of the uncertainty of estimation of the area of registry parcels the impact of the errors of the geodetic network points was determined (points of reference and of the higher class networks) and the effect of the correlation between the coordinates of the same point on the accuracy of the determined plot area. The scope of the correction was determined (in EGiB database) of the plots area, calculated on the basis of re-measurements, performed using equivalent techniques (in terms of accuracy). The analysis of the risk of damage to the underground infrastructure network due to the low quality of spatial data is another research topic presented in the paper. Three main factors have been identified that influence the value of this risk: incompleteness of spatial data sets and insufficient accuracy of determination of the horizontal and vertical position of underground infrastructure. A method for estimation of the project risk has been developed (quantitative and qualitative) and the author’s risk estimation technique, based on the idea of fuzzy logic was proposed. Maps (2D and 3D) of the risk of damage to the underground infrastructure network were developed in the form of large-scale thematic maps, presenting the design risk in qualitative and quantitative form. The data quality model is a set of rules used to describe the quality of these data sets. The model that has been proposed defines a standardized approach for assessing and reporting the quality of EGiB, GESUT and BDOT500 spatial data bases. Quantitative and qualitative rules (automatic, office and field) of data sets control were defined. The minimum sample size and the number of eligible nonconformities in random samples were determined. The data quality elements were described using the following descriptors: range, measure, result, and type and unit of value. Data quality studies were performed according to the users needs. The values of impact weights were determined by the hierarchical analytical process method (AHP). The harmonization of conceptual models of EGiB, GESUT and BDOT500 databases with BDOT10k database was analysed too. It was found that the downloading and supplying of the information in BDOT10k creation and update processes from the analyzed registers are limited. An effective approach to providing spatial data sets users with information concerning data uncertainty are cartographic visualization techniques. Based on the author’s own experience and research works on the quality of official spatial database data examination, the set of methods for visualization of the uncertainty of data bases EGiB, GESUT and BDOT500 was defined. This set includes visualization techniques designed to present three types of uncertainty: location, attribute values and time. Uncertainty of the position was defined (for surface, line, and point objects) using several (three to five) visual variables. Uncertainty of attribute values and time uncertainty, describing (for example) completeness or timeliness of sets, are presented by means of three graphical variables. The research problems presented in the paper are of cognitive and application importance. They indicate on the possibility of effective evaluation of the quality of spatial data collected in public registers and may be an important element of the expert system.
Book chapters on the topic "Plot errors"
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Groß, Thomas. "Statistical Reliability of 10 Years of Cyber Security User Studies." In Lecture Notes in Computer Science, 171–90. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-79318-0_10.
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AbstractBackground. In recent years, cyber security user studies have been appraised in meta-research, mostly focusing on the completeness of their statistical inferences and the fidelity of their statistical reporting. However, estimates of the field’s distribution of statistical power and its publication bias have not received much attention.Aim. In this study, we aim to estimate the effect sizes and their standard errors present as well as the implications on statistical power and publication bias.Method. We built upon a published systematic literature review of 146 user studies in cyber security (2006–2016). We took into account 431 statistical inferences including t-, $$\chi ^2$$ χ 2 -, r-, one-way F-tests, and Z-tests. In addition, we coded the corresponding total sample sizes, group sizes and test families. Given these data, we established the observed effect sizes and evaluated the overall publication bias. We further computed the statistical power vis-à-vis of parametrized population thresholds to gain unbiased estimates of the power distribution.Results. We obtained a distribution of effect sizes and their conversion into comparable log odds ratios together with their standard errors. We, further, gained funnel-plot estimates of the publication bias present in the sample as well as insights into the power distribution and its consequences.Conclusions. Through the lenses of power and publication bias, we shed light on the statistical reliability of the studies in the field. The upshot of this introspection is practical recommendations on conducting and evaluating studies to advance the field.
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Goos, Peter. "Compound Symmetric Error Structure." In The Optimal Design of Blocked and Split-Plot Experiments, 71–101. New York, NY: Springer New York, 2002. http://dx.doi.org/10.1007/978-1-4613-0051-9_3.
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Monaco, Giulia. "Il Laurenziano Pluteo 42, 3 e la tradizione caratterizzante del Decameron." In Intorno a Boccaccio / Boccaccio e dintorni 2020, 97–108. Florence: Firenze University Press, 2021. http://dx.doi.org/10.36253/978-88-5518-510-3.06.
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The aim of this article is to illustrate the most relevant results of the philological and textual analysis that I accomplished on a witness of Boccaccio’s Decameron, MS. Firenze, Bibl. Medicea Laurenziana, Plut. 42, 3. The work consisted in an integral collation, based on two Giornate and some loci critici, between Plut. 42, 3 and the most authoritative tradition of Decameron (MSS. Berlin, Staatsbibl., Ham. 90, Paris, Bibl. nationale de France, It. 482 and Firenze, Bibl. Med. Laur., Plut. 42, 1). On one hand, the purpose of this work is to demonstrate that the text transmitted by Plut. 42, 3 is contaminated and altered by errors and innovations, therefore unusable for a new critical edition of the work; on the other hand, it leads us to an investigation into the existence of a «characterizing tradition» of Decameron.
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Quicke, Donald L. J., Buntika A. Butcher, and Rachel A. Kruft Welton. "Plotting biological data in various ways." In Practical R for biologists: an introduction, 37–78. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789245349.0037.
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Abstract This chapter introduces plotting line graphs, bar charts, pie charts, box and whisker plots. It will troubleshoot the main areas where you are likely to encounter problems. It will show how to create log plots, add legends, error bars, notches and confidence limits, and introduce confidence limits and statistical testing. Examples are given, including bryophytes up a mountain; relationship between rural population size and the potential remaining intact forest; dietary differences between hornbill species (Buceros bicornis, Rhyticeros undulatus, Anthracoceros albirostris and Anorrhinus (Ptilolaemus) tickelli); and study of the level of trematode infection in various species of fish in Thailand.
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Quicke, Donald L. J., Buntika A. Butcher, and Rachel A. Kruft Welton. "Plotting biological data in various ways." In Practical R for biologists: an introduction, 37–78. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789245349.0006.
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Abstract This chapter introduces plotting line graphs, bar charts, pie charts, box and whisker plots. It will troubleshoot the main areas where you are likely to encounter problems. It will show how to create log plots, add legends, error bars, notches and confidence limits, and introduce confidence limits and statistical testing. Examples are given, including bryophytes up a mountain; relationship between rural population size and the potential remaining intact forest; dietary differences between hornbill species (Buceros bicornis, Rhyticeros undulatus, Anthracoceros albirostris and Anorrhinus (Ptilolaemus) tickelli); and study of the level of trematode infection in various species of fish in Thailand.
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Pini, Riccardo, Maria Luisa Ralli, and Saravanakumar Shanmugam. "Emergency Department Clinical Risk." In Textbook of Patient Safety and Clinical Risk Management, 189–203. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-59403-9_15.
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AbstractThe emergency department of any institution is an entry point for a significant number of patients to any health care organization. The department caters to various trauma and medical emergencies in both adults and in children round the clock and is adequately staffed with emergency physicians, and nursing to handle such emergencies at all times and days. The department also oversees operations of the prehospital emergency medical services (ambulance) and coordinates their services.The emergency department (ED) is considered particularly high risk for adverse events (AE): 60% of ED patients experienced Medication Error (Patanwala et al., Ann Emerg Med 55:522–526, 2010). From a systematically review about AE related to ED, appears that the prevalence of AE among hospitalized patients ranging from 2.9% to 16.6%, with 36.9% to 51% of events considered preventable (Stang et al., PLoS One 8:e74214, 2013).Maintaining quality and developing error-free systems have been the focus of engineering over the last few decades.Consider the degree of variability of every individual human being compared to machine and also wisdoms from engineering field, for error-free system that guarantees good quality assistance should be defined a program reasonably simple, locally relevant, easily implementable, not be resource intense and have tangible outcomes which can be measured.
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Ochoa, Gabriela. "Consensus Sequence Plots and Error Thresholds: Tools for Visualising the Structure of Fitness Landscapes." In Parallel Problem Solving from Nature PPSN VI, 129–38. Berlin, Heidelberg: Springer Berlin Heidelberg, 2000. http://dx.doi.org/10.1007/3-540-45356-3_13.
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Castro-Santana, Anaclara. "From Sham Marriage to a Proper Marriage Plot." In Errors and Reconciliations, 107–27. Routledge, 2018. http://dx.doi.org/10.4324/9781315197593-4.
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Castro-Santana, Anaclara. "The Criminal Marriage Plot of The Female Husband." In Errors and Reconciliations, 145–73. Routledge, 2018. http://dx.doi.org/10.4324/9781315197593-6.
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Kukkonen, Karin. "Plots and Probability Transformations." In Probability Designs, 15–29. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780190050955.003.0002.
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In the chapters that follow, the first-order probability design around narrative plot is developed. I.1: Plot and Probability Transformations concerns itself with plot events and prediction errors. I.2: Probability Designs discusses the links between design, the creative process, and the author’s intentionality. Finally, I.3: The Height of Drop addresses how readers’ perception of probabilities is manipulated.
Conference papers on the topic "Plot errors"
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Bester, A., and P. Meyer. "Locating sources of reflection errors in an anechoic chamber by creating an error surface plot." In 2020 14th European Conference on Antennas and Propagation (EuCAP). IEEE, 2020. http://dx.doi.org/10.23919/eucap48036.2020.9135072.
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Wu, Jun, and Iraj Ershaghi. "Errors Associated With the Application of the G-Function Plot for Analyzing Pressure Fall-Off Tests in Water Injection Wells." In SPE Western Regional Meeting. SPE, 2021. http://dx.doi.org/10.2118/200790-ms.
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Abstract Castillo1 suggested the use of the G-Function plot based on the work of Nolte2. It has been a standard practice in the fracturing community to estimate the fracture closing pressure from a tangent to the G*dp/dg plot. In this analysis technique, the assumption is that a fracture has already developed under the high-pressure fracturing fluid. Then when the pumping is relaxed, one can estimate the fracture closing pressure. In many California waterfloods, the issue of maximum allowable injection gradient has been debated. Various solutions have been proposed to calculate a safe injection gradient. One method that has been promoted is the application of the G-function plot. In this paper, we maintain that this application can be misleading using the prescribed cartesian G function plots. We present the results of an extensive research study for analyzing pressure fall-off data using the G-Plot function. We studied a reappraisal of the G function plot using waterflood conditions where no prior fractures had formed, and no fracture closing pressure was meaningful or applicable. We show from analysis of generated data, using both numerical reservoir modeling and analytical derivations for a radial flow system, that fall-off tests analyzed using the cartesian G function can generate false indications of fracture closing where in fact, the entire injection has been based on radial flow homogeneous injection systems. We also studied systems with a pre-existing fracture before injection. We show that if such a reservoir system is subjected to injection and fall-off tests, again, one may compute a false indication of the irrelevant fracture closure pressure. We discuss how the cartesian scale used for the G function plot can be misleading for the analysis of fall-off test data.
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Qi, Qianru, Sophie Pepin, Abdula AlJazzaf, and Iraj Ershaghi. "Errors Associated with Waterflood Monitoring Using the Hall Plot for Stacked Reservoirs in the Absence of Profile Surveys." In SPE Western Regional Meeting. Society of Petroleum Engineers, 2017. http://dx.doi.org/10.2118/185694-ms.
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Abdolrazaghi, Mona, Sherif Hassanien, and Karmun Cheng. "Relative Statistical Calibration of ILI Measurements." In 2016 11th International Pipeline Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/ipc2016-64126.
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In-Line inspection tools (ILI) including Magnetic Flux Leakage (MFL) and Ultrasonic (UT) technologies are commonly used to detect/measure potential anomalies in oil and gas pipelines. Some of ILI reported anomalies are usually selected for excavation and validated through field non-destructive examination techniques (NDE). It is a fact that both ILI and NDE readings are contaminated with measurement errors. Such errors are usually originated from inherent tool limitations and capabilities, measurement techniques, and/or human factors. The intend of this paper is to calibrate the corrosion ILI data relative to NDE measurement given estimated statistical errors from both tools. Commonly, a graphical representation is used to compare ILI versus field measurements; namely, a unity plot. Herein, a linear relationship between ILI and NDE measurements is assumed. Such an assumption leads to another assumption of having a linear relationship between the ILI measurement and true value. Similarly, NDE measurement has the same relationship with the true value. An advanced statistical approach based on linear regression and maximum likelihood is used to determine the uncertainty of both ILI and NDE measurement errors. This method is based on first quantifying the uncertainty of ILI and field measurement and then calibrating the ILI data relative to the field using the estimated tools errors. The tool error estimation is based on reducing the relative error between ILI and field measurements. The calibration methodology implements advanced statistics to improve both accuracy and precision of measurement data. The proposed process is validated through results from successive ILI programs. The proposed calibration can be easily adopted in ubiquitous computing spreadsheet environment and be applied to both corrosion and crack measurements.
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MOZGERIS, Gintautas, Ina BIKUVIENĖ, and Donatas JONIKAVICIUS. "THE OPPORTUNITIES AND CHALLENGES OF USING AIRBORNE LASER SCANNING FOR FOREST INVENTORIES IN LITHUANIA." In RURAL DEVELOPMENT. Aleksandras Stulginskis University, 2018. http://dx.doi.org/10.15544/rd.2017.023.
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The aim of this study was to test the usability of airborne laser scanning (ALS) data for stand-wise forest inventories in Lithuania based on operational approaches from Nordic countries, taking into account Lithuanian forest conditions and requirements for stand-wise inventories, such as more complex forests, unified requirements for inventory of all forests, i.e. no matter the ownership, availability of supporting material from previous inventories and high accuracy requirements for total volume estimation. Test area in central part of Lithuania (area 2674 ha) was scanned using target point density 1 m-2 followed by measurements of 440 circular field plots (area 100–500 m2). Detailed information on 22 final felling areas with all trees callipered (total area 42.7 ha) was made available to represent forest at mature age. Updated information from conventional stand-wise inventory was made available for the whole study area, too. A two phase sampling with nonparametric Most Similar Neighbor estimator was used to predict point-wise forest characteristics. Total volume of the stand per 1 ha was predicted with an root mean square error of 18.6 %, basal area – 17.7 %, mean diameter – 13.6 %, mean height – 7.9 % and number of tree – 42.8 % at plot-level with practically no significant bias. However, the relative root mean square errors increased 2–4 times when trying to predict forest characteristics by three major groups of tree species – pine, spruce and all deciduous trees taken together. Main conclusion of the study was that accuracy of predicting volume using ALS data decreased notably when targeting forest characteristics by three major groups of tree species.
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Gao, Limin, Xiaoquan Hu, Linchuan Tian, and Ruiyu Li. "Pressure Field Measurement on Compressor Cascade Using Pressure-Sensitive Paint." In ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/gt2016-57082.
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In the current work, pressure distribution on the surface of blade and endwall is investigated experimentally in a compressor cascade for capturing some flow features by analyzing pressure profile aerodynamics. Pressure is measured using pressure sensitive paint (PSP) technique. Before the tests, some system errors including temperature-dependence of paint, in-situ calibration, and Self-illumination among neighboring structure are studied in details. In addition, the spatial layout scheme of LEDs and CCDs for each test is designed by self-developing optical theoretical method that based on the LTS (light Tracing Simulation). In the post-processing, an in-situ calibration is conducted to convert the intensity of luminescence to pressure, and each test uses independent calibration equation. Finally, discrete pressure is also measured by pressure taps to compare with PSP. All of the tests are performed at the AOA (Attack of Angle) of −2.5°∼10°, and Mach number of 0.4∼0.8. The results show that the pressure distribution at low Mach number presents a good PSP performance in terms of signal-to-noise-ratio, and apparent pressure step gradient is captured at high Mach number. Meanwhile, the pressure distribution at high incidence reveals the unsteady of separated flow. By combining the end-wall plot with profile plot, the influence of corner-flow on main flow in the passage is obtained.
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Behmanesh, H., H. Hamdi, and C. R. Clarkson. "Analysis of Transient Linear Flow Associated with Hydraulically-Fractured Tight Oil Wells Exhibiting Multi-Phase Flow." In SPE Middle East Unconventional Resources Conference and Exhibition. SPE, 2015. http://dx.doi.org/10.2118/spe-172928-ms.
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Abstract Hydraulically-fractured vertical and horizontal wells completed in the tight formations typically exhibit long periods of transient linear flow that may last many years or decades. From this transient linear flow period, the linear flow parameter (xf√k) may be extracted. However, changes in effective permeability to the oil phase during production, caused by wellbore pressure falling below the saturation pressure, affect the flow dynamics in tight oil reservoirs and complicate the analysis. The use of methods that assume single-phase flow properties, such as the square-root of time plot, can lead to significant errors in linear flow parameter estimates. In this study, an analytical method is introduced to mathematically correct the slope of the square-root-of-time plot for the effects of multi-phase flow through the use of modified pseudovariables. Although the correction was derived for wells producing at constant flowing pressure during transient linear flow, the method is extended for wells producing at variable rate/flowing pressures. In order to evaluate pseudovariables used in the correction, the saturation-pressure relationship must be known. In this work, an analytical method for evaluating the saturation-pressure relationship is also developed. The results of our new analytical method for linear flow analysis are validated against numerical simulation. The new method yields linear flow parameter estimates that are within 10% of those input into the numerical simulator.
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Rainsberger, Robert B., Jeffrey T. Fong, and Pedro V. Marcal. "A Super-Parametric Approach to Estimating Accuracy and Uncertainty of the Finite Element Method (*)." In ASME 2016 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/pvp2016-63890.
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A finite element method (FEM)-based solution of an industry-grade problem with complex geometry, partially-validated material property databases, incomplete knowledge of prior loading histories, and an increasingly user-friendly human-computer interface, is extremely difficult to verify because of at least five major sources of errors or solution uncertainty (SU), namely, (SU-1) numerical algorithm of approximation for solving a system of partial differential equations with initial and boundary conditions; (SU-2) the choice of the element type in the design of a finite element mesh; (SU-3) the choice of a mesh density; (SU-4) the quality measures of a finite element mesh such as the mean aspect ratio.; and (SU-5) the uncertainty in the geometric parameters, the physical and material property parameters, the loading parameters, and the boundary constraints. To address this problem, a super-parametric approach to FEM is developed, where the uncertainties in all of the known factors are estimated using three classical tools, namely, (a) a nonlinear least squares logistic fit algorithm, (b) a relative error convergence plot, and (c) a sensitivity analysis based on a fractional factorial orthogonal design of experiments approach. To illustrate our approach, with emphasis on addressing the mesh quality issue, we present a numerical example on the elastic deformation of a cylindrical pipe with a surface crack and subjected to a uniform load along the axis of the pipe.
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Moody, F. J. "Engineered Security Measures of Nuclear Power Plants." In ASME 2003 Pressure Vessels and Piping Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/pvp2003-1808.
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Even in the absence of depraved terrorist threats, nuclear plants have been designed to respond safely to postulated accidents. Redundant safety features are built into plants to trigger safe shutdown and containment of possible accidents. The defined accidents range from minor leakage and operator errors to a complete loss of coolant from the reactor. Post-accident scenarios are postulated by experts in reactor and containment thermal-hydraulics, and all other sciences embraced by nuclear power plant design. The probability of failure is determined for all engineered safety systems. Then analytical and experimental programs are employed to predict the long term post-accident thermal-hydraulic state of a plant and its effect on the environment. The postulated accidents and safety system responses include effects resulting from mechanical damage and component malfunctions, such as pipe ruptures and the failure of pumps and valves. The initiating causes can be material failure, human error, and environmental effects from earthquakes, floods, and other severe acts of nature. It is prudent to build on an already established safety and accident technology to include the effects of external, planned attacks on a nuclear plant. This process includes “matching wits” with the minds of those who plot evil, and reinforcing protective security barriers where potential vulnerabilities are detected. Hard questions to ask and answer are, “What are the greatest potential security threats to a nuclear power plant? What possible human activity could make them happen? How can they be prevented?” Reactor and containment thermal-hydraulics contributes significantly to answering these questions.
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Noury, Keyvan, and Bingen Yang. "Class of Stabilizing Parallel Feedforward Compensators for Nonminimum-Phase Systems." In ASME 2019 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/dscc2019-9240.
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Abstract In this work, the properties of the class of parallel feedforward compensators to stabilize linear closed-loop systems are studied. The characteristic equation and its root locus behavior, including its asymptotes, are investigated to leave out the compensators that will not result in a stable closed-loop system. Even though there have been numerous studies relevant to parallel feedforward compensation that result in the optimal integration of squared errors (ISE), the broader view of all possible compensators has not been of much interest in the literature. Nevertheless, this study is important because, in the presence of noise and disturbance, an optimal ISE control design for the nominal plant may perform poorly while a finite ISE design may have a robust and efficient performance. One of such class compensators is parallel feedforward compensator with derivative effort (PFCD) that for a vast number of processes can have impressive properties such as no branch comebacks to the right half plane (RHP) of the root locus plot (LHP black hole effect). The example in this paper shows how effectively PFCD can contract the root locus branches into the LHP.
Reports on the topic "Plot errors"
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Leis, Sherry. Vegetation community monitoring at Lincoln Boyhood National Memorial: 2011–2019. National Park Service, April 2021. http://dx.doi.org/10.36967/nrr-2284711.
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Lincoln Boyhood National Memorial celebrates the lives of the Lincoln family including the final resting place of Abraham’s mother, Nancy Hanks Lincoln. Lincoln’s childhood in Indiana was a formative time in the life our 16th president. When the Lincoln family arrived in Indiana, the property was covered in the oak-hickory forest type. They cleared land to create their homestead and farm. Later, designers of the memorial felt that it was important to restore woodlands to the site. The woodlands would help visitors visualize the challenges the Lincoln family faced in establishing and maintaining their homestead. Some stands of woodland may have remained, but significant restoration efforts included extensive tree planting. The Heartland Inventory and Monitoring Network began monitoring the woodland in 2011 with repeat visits every four years. These monitoring efforts provide a window into the composition and structure of the wood-lands. We measure both overstory trees and the ground flora within four permanently located plots. At these permanent plots, we record each species, foliar cover estimates of ground flora, diameter at breast height of midstory and overstory trees, and tree regeneration frequency (tree seedlings and saplings). The forest species composition was relatively consistent over the three monitoring events. Climatic conditions measured by the Palmer Drought Severity Index indicated mild to wet conditions over the monitoring record. Canopy closure continued to indicate a forest structure with a closed canopy. Large trees (>45 cm DBH) comprised the greatest amount of tree basal area. Sugar maple was observed to have the greatest basal area and density of the 23 tree species observed. The oaks characteristic of the early woodlands were present, but less dominant. Although one hickory species was present, it was in very low abundance. Of the 17 tree species recorded in the regeneration layer, three species were most abundant through time: sugar maple (Acer saccharum), red bud (Cercis canadensis), and ash (Fraxinus sp.). Ash recruitment seemed to increase over prior years and maple saplings transitioned to larger size classes. Ground flora diversity was similar through time, but alpha and gamma diversity were slightly greater in 2019. Percent cover by plant guild varied through time with native woody plants and forbs having the greatest abundance. Nonnative plants were also an important part of the ground flora composition. Common periwinkle (Vinca minor) and Japanese honeysuckle (Lonicera japonica) continued to be the most abundant nonnative species, but these two species were less abundant in 2019 than 2011. Unvegetated ground cover was high (mean = 95%) and increased by 17% since 2011. Bare ground increased from less than 1% in 2011 to 9% in 2019, but other ground cover elements were similar to prior years. In 2019, we quantified observer error by double sampling two plots within three of the monitoring sites. We found total pseudoturnover to be about 29% (i.e., 29% of the species records differed between observers due to observer error). This 29% pseudoturnover rate was almost 50% greater than our goal of 20% pseudoturnover. The majority of the error was attributed to observers overlooking species. Plot frame relocation error likely contributed as well but we were unable to separate it from overlooking error with our design.
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van Hees, Willem W. S. A comparison of two estimates of standard error for a ratio-of-means estimator for a mapped-plot sample design in southeast Alaska. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station, 2002. http://dx.doi.org/10.2737/pnw-rn-532.
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Alchanatis, Victor, Stephen W. Searcy, Moshe Meron, W. Lee, G. Y. Li, and A. Ben Porath. Prediction of Nitrogen Stress Using Reflectance Techniques. United States Department of Agriculture, November 2001. http://dx.doi.org/10.32747/2001.7580664.bard.
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Commercial agriculture has come under increasing pressure to reduce nitrogen fertilizer inputs in order to minimize potential nonpoint source pollution of ground and surface waters. This has resulted in increased interest in site specific fertilizer management. One way to solve pollution problems would be to determine crop nutrient needs in real time, using remote detection, and regulating fertilizer dispensed by an applicator. By detecting actual plant needs, only the additional nitrogen necessary to optimize production would be supplied. This research aimed to develop techniques for real time assessment of nitrogen status of corn using a mobile sensor with the potential to regulate nitrogen application based on data from that sensor. Specifically, the research first attempted to determine the system parameters necessary to optimize reflectance spectra of corn plants as a function of growth stage, chlorophyll and nitrogen status. In addition to that, an adaptable, multispectral sensor and the signal processing algorithm to provide real time, in-field assessment of corn nitrogen status was developed. Spectral characteristics of corn leaves reflectance were investigated in order to estimate the nitrogen status of the plants, using a commercial laboratory spectrometer. Statistical models relating leaf N and reflectance spectra were developed for both greenhouse and field plots. A basis was established for assessing nitrogen status using spectral reflectance from plant canopies. The combined effect of variety and N treatment was studied by measuring the reflectance of three varieties of different leaf characteristic color and five different N treatments. The variety effect on the reflectance at 552 nm was not significant (a = 0.01), while canonical discriminant analysis showed promising results for distinguishing different variety and N treatment, using spectral reflectance. Ambient illumination was found inappropriate for reliable, one-beam spectral reflectance measurement of the plants canopy due to the strong spectral lines of sunlight. Therefore, artificial light was consequently used. For in-field N status measurement, a dark chamber was constructed, to include the sensor, along with artificial illumination. Two different approaches were tested (i) use of spatially scattered artificial light, and (ii) use of collimated artificial light beam. It was found that the collimated beam along with a proper design of the sensor-beam geometry yielded the best results in terms of reducing the noise due to variable background, and maintaining the same distance from the sensor to the sample point of the canopy. A multispectral sensor assembly, based on a linear variable filter was designed, constructed and tested. The sensor assembly combined two sensors to cover the range of 400 to 1100 nm, a mounting frame, and a field data acquisition system. Using the mobile dark chamber and the developed sensor, as well as an off-the-shelf sensor, in- field nitrogen status of the plants canopy was measured. Statistical analysis of the acquired in-field data showed that the nitrogen status of the com leaves can be predicted with a SEP (Standard Error of Prediction) of 0.27%. The stage of maturity of the crop affected the relationship between the reflectance spectrum and the nitrogen status of the leaves. Specifically, the best prediction results were obtained when a separate model was used for each maturity stage. In-field assessment of the nitrogen status of corn leaves was successfully carried out by non contact measurement of the reflectance spectrum. This technology is now mature to be incorporated in field implements for on-line control of fertilizer application.