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A robust variable step size least mean fourth with a quotient form control scheme (RVSSLMFQ) is implemented for addressing power quality concerns and delivering clean voltage to sensitive loads through a dynamic voltage restorer (DVR). This method estimates the fundamental components from distorted grid voltages, featuring an automated process with adaptive time-varying step sizes and utilizing a quotient structure to reduce mean squared error (MSE) effectively. The suggested control scheme overcomes the stability and performance issues of the least mean fourth (LMF) algorithm by improving convergence and adapting well to varying step sizes. Furthermore, RVSSLMFQ achieves remarkable results with reduced settling time and fewer peak overshoots compared to the least mean square (LMS) and LMF control algorithms. For tuning the load voltage and DC-link voltage proportional-integral (PI) controllers, the improved grey wolf optimization technique (I-GWO) is applied. The results are evaluated through MATLAB simulations. [ABSTRACT FROM AUTHOR]

Background: To assess contrast-enhanced mammography (CEM) in the management of BI-RADS3 breast architectural distortions (AD) in digital breast tomosynthesis (DBT). Methods: We retrospectively reviewed 328 women with 332 ADs detected on DBT between 2017 and 2021 and selected those classified as BI-RADS3 receiving CEM as problem-solving. In CEM recombined images, we evaluated AD's contrast enhancement (CE) according to its presence/absence, type, and size. AD with enhancement underwent imaging-guided biopsy while AD without enhancement follow-up or biopsy if detected in high/intermediate-risk women. Results: AD with enhancement were 174 (52.4%): 72 (41.4%) were malignant lesions, 102 (59.6%) false positive results: 28 (16%) B3 lesions, and 74 (42.5%) benign lesions. AD without enhancement were 158 (47.6%): 26 (16.5%) were subjected to biopsy (1 malignant and 25 benign) while the other 132 cases were sent to imaging follow-up, still negative after two years. CEM's sensitivity, specificity, positive (PPV) and negative predictive values (NPV), and accuracy were 98.63%, 60.62%, 41.38%, 99.37%, and 68.98%. The AUC determined by ROC was 0.796 (95% CI, 0.749–0.844). Conclusion: CEM has high sensitivity and NPV in evaluating BI-RADS3 AD and can be a complementary tool in assessing AD, avoiding unnecessary biopsies without compromising cancer detection. [ABSTRACT FROM AUTHOR]

Purpose: This study examines how MRI distortions affect frame‐based SRS treatments and assesses the need for clinical distortion corrections. Methods: The study included 18 patients with 80 total brain targets treated using frame‐based radiosurgery. Distortion within patients' MRIs were corrected using Cranial Distortion Correction (CDC) software, which utilizes the patient's CT to alter planning MRIs to reduce inherent intra‐cranial distortion. Distortion was evaluated by comparing the original planning target volumes (PTVORIG) to targets contoured on corrected MRIs (PTVCORR). To provide an internal control, targets were also re‐contoured on uncorrected (PTVRECON) MRIs. Additional analysis was done to assess if 1 mm expansions to PTVORIG targets would compensate for patient‐specific distortions. Changes in target volumes, DICE and JACCARD similarity coefficients, minimum PTV dose (Dmin), dose to 95% of the PTV (D95%), and normal tissue receiving 12 Gy (V12Gy), 10 Gy (V10Gy), and 5 Gy (V5Gy) were calculated and evaluated. Student's t‐tests were used to determine if changes in PTVCORR were significantly different than intra‐contouring variability quantified by PTVRECON. Results: PTVRECON and PTVCORR relative changes in volume were 6.19% ± 10.95% and 1.48% ± 32.92%. PTVRECON and PTVCORR similarity coefficients were 0.90 ± 0.08 and 0.73 ± 0.16 for DICE and 0.82 ± 0.12 and 0.60 ± 0.18 for JACCARD. PTVRECON and PTVCORR changes in Dmin were –0.88% ± 8.77% and −12.9 ± 17.3%. PTVRECON and PTVCORR changes in D95% were −0.34% ± 5.89 and −8.68% ± 13.21%. The 1 mm expanded PTVORIG targets did not entirely cover 14 of the 80 PTVCORR targets. Normal tissue changes (V12Gy, V10Gy, V5Gy) calculated with PTVRECON were (−0.09% ± 7.39%, −0.38% ± 5.67%, −0.08% ± 2.04%) and PTVCORR were (−2.14% ± 7.34%, −1.42% ± 5.45%, −0.61% ± 1.93%). Except for V10Gy, all PTVCORR changes were significantly different (p < 0.05) than PTVRECON. Conclusion: MRIs used for SRS target delineation exhibit notable geometric distortions that may compromise optimal dosimetric accuracy. A uniform 1 mm expansion may result in geometric misses; however, the CDC algorithm provides a feasible solution for rectifying distortions, thereby enhancing treatment precision. [ABSTRACT FROM AUTHOR]

The comparative evaluation of the performance of a mobile device camera and an affordable full-frame mirrorless camera in close-range photogrammetry applications involves assessing the capabilities of these two types of cameras in capturing images for 3D measurement purposes. In this study, experiments are conducted to compare the distortion levels, the accuracy performance, and the image quality of a mobile device camera against a full-frame mirrorless camera when used in close-range photogrammetry applications in various settings. Analytical methodologies and specialized digital tools are used to evaluate the results. In the end, generalized conclusions are drawn for using each technology in close-range photogrammetry applications. [ABSTRACT FROM AUTHOR]

This paper investigates how sectoral linkages amplify or diminish misallocation at the intensive and extensive margins. Our analysis is based on a multisector general equilibrium model with input–output linkages, heterogeneous entrepreneurial abilities, and endogenous occupational choice. Distortions affect the intensive use of production inputs and they also impact the agents' occupational decisions, misallocating the mass and type of entrepreneurs in different sectors of production. When the most distorted sectors are upstream (downstream), input–output linkages amplify (diminish) the loss from entreprenurial misallocation. We calibrate the model to the US and quantify the output losses from sectoral corporate taxes, decomposing the role of networks and the extensive margin decisions. We find that sectoral linkages quadruple the loss from the misallocation of entrepreneurs. We study an entry subsidy program, showing that it should target those sectors whose marginal entrepreneurs suffer larger profit losses, even if they are not necessarily the most distorted. [ABSTRACT FROM AUTHOR]

This study aimed to analyze and optimize the thermal induction hardening process applied to toothed transmission gears, focusing on thermal aspects, structural deformation, and topology optimization, while exploring the feasibility of various materials and operating conditions. The research simulated thermal and deformation behavior using a computer model, comparing results with experimental data through the Ansys® platform 2022 R1. The methodology encompassed thermal and deformation analyses, topology optimization to identify removable regions without compromising part integrity, and a sensitivity study to evaluate the different materials and operating conditions. This study validates the precision of computational models in predicting thermal and deformation behavior in toothed gears under thermal induction hardening, introducing topology optimizations and alternative materials, and providing novel perspectives for the more efficient and cost-effective manufacturing of these components. Comparative thermal analysis revealed a maximum relative error of less than 6% between temperatures from the computer model and experimental results, while deformation comparisons exhibited a maximum relative error of less than 7%, affirming the simulation model's accuracy in predicting and managing deformations within acceptable thresholds. Topology optimization successfully pinpointed removable regions without compromising structural integrity, enabling the production of lighter and more economical devices. Future endeavors should concentrate on additional tests to verify the feasibility of reducing power and cooling temperature without compromising product specifications. Furthermore, it is advisable to explore alternative materials and apply the developed methodology in diverse industrial settings to generalize the findings and amplify the impact of the proposed optimizations. [ABSTRACT FROM AUTHOR]

Capturing laparoscopic videos helps physicians to conduct minor surgeries and treatments effectively. But the problem is that these videos are easily affected by environmental conditions and various distortions that diminish the overall clarity. This reduces the possibility for physicians to complete the treatments successfully. To deal with this, video enhancement techniques are introduced, which require the help of effective distortion-type classification strategies. This work presents a compelling and accurate distortion classification technique based on transfer learning. The proposed work includes three main stages: feature extraction, fine-tuning and classification. The DenseNet-65 convolutional neural network (DDCNN) model has been chosen as the baseline, where the DenseNet-65 is pre-trained on the Imagenet dataset. The pre-trained model is used for feature extraction using the zero-shot transfer learning (ZSTL) technique, where only the first few layers of a model are engaged to extract the crucial spatial features. Then, the fine-tuning process was carried out using the flow direction algorithm (FDA) that tunes the parameters of the top layers. Finally, classification has been done using the softmax classifier, where the model classifies five different distortions in videos such as smoke, AWGN noise, motion blur, defocus blur and uneven illumination. The work has been implemented in Python, and the ICIP2020 challenge dataset is used for evaluations. The achieved accuracy outcomes of different distortion classes are smoke (97.8%), AWGN noise (100%), Motion blur (95.83%), Defocus blur (98.65%) and uneven illumination (99.01%). Moreover, the performance of a proposed scheme is examined in terms of different performance measures accuracy (98.8%), F1-score (96.9%), processing time (0.037 s), Spearman rank order correlation coefficient SROCC (0.995), Pearson linear correlation coefficient (PLCC) (0.995), and Kendall rank order correlation coefficient (KROCC) (0.857). The performance evaluations proved the efficacy of the proposed method compared to other techniques. [ABSTRACT FROM AUTHOR]

Agency is central to remote actions, and it may enhance skills learning due to a partial overlap between brain structures and networks, the promotion of confidence towards a telemanipulator, and the feeling of congruence of the motor choice to the motor plan. We systematically reviewed studies aiming to verify the role of agency in improving learning. Fifteen studies were selected from MEDLINE and Scopus®. When a mismatch is introduced between observed and performed actions, the decrease in agency and learning is proportional to the intensity of the mismatch, which is due to greater interference with the motor programming. Thanks to multisensory integration, agency and learning benefit both from sensory and performance feedback and from the timing of feedback based on control at the goal level or the perceptual–motor level. This work constitutes a bedrock for professional teleoperation settings (e.g., robotic surgery), with particular reference to the role of agency in performing complex tasks with remote control. [ABSTRACT FROM AUTHOR]

Visual and haptic perceptions of 3D shape are plagued by distortions, which are influenced by nonvisual factors, such as gravitational vestibular signals. Whether gravity acts directly on the visual or haptic systems or at a higher, modality-independent level of information processing remains unknown. To test these hypotheses, we examined visual and haptic 3D shape perception by asking male and female human subjects to perform a “squaring” task in upright and supine postures and in microgravity. Subjects adjusted one edge of a 3D object to match the length of another in each of the three canonical reference planes, and we recorded the matching errors to obtain a characterization of the perceived 3D shape. The results show opposing, body-centered patterns of errors for visual and haptic modalities, whose amplitudes are negatively correlated, suggesting that they arise in distinct, modality-specific representations that are nevertheless linked at some level. On the other hand, weightlessness significantly modulated both visual and haptic perceptual distortions in the same way, indicating a common, modality-independent origin for gravity’s effects. Overall, our findings show a link between modality-specific visual and haptic perceptual distortions and demonstrate a role of gravity-related signals on a modality-independent internal representation of the body and peripersonal 3D space used to interpret incoming sensory inputs. [ABSTRACT FROM AUTHOR]

Distortions and resource misallocation cause large productivity losses, especially in developing countries. But removing (all) distortions is infeasible in practice. Policymakers face second-best policy options at best. However, empirical studies typically do not show the productivity gain from a partial removal of distortions. In this paper we analyze the productivity gain from (only) removing ownership distortions within the Hsieh and Klenow (2009) framework using the Vietnam Enterprise Census over the period 2000–2015. We show analytically how the productivity gains from a removal of ownership distortions depends on their covariances with other distortions. Empirically, state-owned enterprises and foreign firms experience significantly lower capital distortions than private firms in most manufacturing industries. However, the removal of ownership distortions has little impact because of complementary size-dependent distortions in Vietnam. This type of analysis can support policymakers in designing productivity enhancing policy interventions in the presence of complementarities. [ABSTRACT FROM AUTHOR]

The two primary physical methods for identifying lithium titanate, a negative electrode material used commercially, are X-Ray diffraction and Raman spectroscopy. Although there are many publications on this topic, they are focused mainly on chemistry, so there are still some points that require clarification from a physical and methodological point of view. Difference of experimentally observed and theoretically predicted Raman spectra was explained through a combination of experiments and computations. The work comprises experiments and computations to explain why there are different numbers of predicted and observed Raman-active bands. Our low-temperature study and the analysis of thermal shifts during heating led us to conclude that the approach with surplus bands is advantageous and we recommend using major F2g band shifts to estimate the sample heating. [ABSTRACT FROM AUTHOR]

For decades, manufacturers have attempted to reduce or eliminate the optical aberrations that appear on the progressive addition lens’ surfaces during manufacturing. Besides every effort made, some of these distortions are inevitable given how lenses are fabricated, where in fact, astigmatism appears on the surface and cannot be entirely removed, or where non-uniform magnification becomes inherent to the power change across the lens. Some presbyopes may refer to certain discomfort when wearing these lenses for the first time, and a subset of them might never adapt. Developing, prototyping, testing and purveying those lenses into the market come at a cost, which is usually reflected in the retail price. This study aims to test the feasibility of virtual reality (VR) for testing customers’ satisfaction with these lenses, even before getting them onto production. VR offers a controlled environment where different parameters affecting progressive lens comforts, such as distortions, image displacement or optical blurring, can be inspected separately. In this study, the focus was set on the distortions and image displacement, not taking blur into account. Behavioural changes (head and eye movements) were recorded using the built-in eye tracker. We found participants were significantly more displeased in the presence of highly distorted lens simulations. In addition, a gradient boosting regressor was fitted to the data, so predictors of discomfort could be unveiled, and ratings could be predicted without performing additional measurements. [ABSTRACT FROM AUTHOR]

This paper describes a comparative study of the total harmonic distortion (THD) caused by commercial electrolytic capacitors. The study includes selected capacitors with a capacitance of $470~\mu \text{F}$ that are commercially available from eiSos Würth Elektronik, as well as custom-made capacitors that are manufactured at the production site. For the custom-made samples, the water content of the electrolyte, as well as the paper density, was systematically varied. The discussion of audibility of distortion is based on human sound perception. The results are compared with model calculations to check the plausibility of the measured harmonic distortions. This study concludes that capacitors do not introduce significant distortions at fundamental frequencies when transmitting signals. Modifications of the electrolyte or the separator paper practically do not influence the THD.

A method is proposed for uniform approximation of a deformed grid so as to reduce the influence of distortions due to random and systematic errors in determining the coordinates of the grid points. As an illustration, this method is used to assess the strain in extrusion through a channel whose cross section varies in shape. [ABSTRACT FROM AUTHOR]

The purpose of the paper is to explore the connections between skew symmetric, weighted and distorted univariate distributions as well as how they appear related to the distributions of the extreme values in a sample of identically distributed random variables under both the independence and dependence scenarios. Some extensions of the concept of skewed distributions are proposed in order to cover the most general cases of extremes. Their natural connections to the likelihood ratio ordering and the role played by the P–P plots for handling these models are also highlighted. The results can also be applied to order statistics and coherent systems although these cases do not always lead to skewed distributions. The theoretical findings are illustrated by applied examples to model extremes as well as by several applications concerned with the analysis of artificial and real data. [ABSTRACT FROM AUTHOR]

The Tshivenḓa Bible Translations 1936 and 1998 are language tools, which have since the advent of Christianity in Venḓa somewhat contributed to the shaping and reshaping of the language and culture of the Vhavenḓa people. These language tools have also contributed largely to distortion of the Vhavenḓa language and culture and unfortunately the distortions have become normalised to a great extent. The argument in this article is that in as much as the distortions have become normalised through these language tools, they can be reversed through disobedience at various levels and epistemic relinking with the values, customs, traditions and practices of the Vhavenḓa people. Contribution: This article highlights language and cultural distortions inherent in Tshivenda Bible translations (1936 and 1998), and it proposes decolonial measures to rectify these distortions given the widespread use of these texts in the culture.

PurposeTo examine perceptual adaptation when people wear spectacles that produce unequal retinal image magnification.MethodsTwo groups of 15 participants (10 male; mean age 25.6 ± 4.9 years) wore spectacles with a 3.8% horizontal magnifier over one eye. The continuous-wear group wore the spectacles for 5 hours straight. The intermittent-wear group wore them for five 1-hour intervals. To measure slant and shape distortions produced by the spectacles, participants adjusted visual stimuli until they appeared frontoparallel or equiangular, respectively. Adaptation was quantified as the difference in responses at the beginning and end of wearing the spectacles. Aftereffects were quantified as the difference before and after removing the spectacles. We hypothesized that intermittent wear may lead to visual cue reweighting, so we fit a cue combination model to the data and examined changes in weights given to perspective and binocular disparity slant cues.ResultsBoth groups experienced significant shape adaptation and aftereffects. The continuous-wear group underwent significant slant adaptation and the intermittent group did not, but there was no significant difference between groups, suggesting that the difference in adaptation was negligible. There was no evidence for cue reweighting in the intermittent wear group, but unexpectedly, the weight given to binocular disparity cues for slant increased significantly in the continuous-wear group.ConclusionsWe did not find strong evidence that adaptation to spatial distortions differed between the two groups. However, there may be differences in the cue weighting strategies employed when spectacles are worn intermittently or continuously.

The comparative evaluation of the performance of a mobile device camera and an affordable full-frame mirrorless camera in close-range photogrammetry applications involves assessing the capabilities of these two types of cameras in capturing images for 3D measurement purposes. In this study, experiments are conducted to compare the distortion levels, the accuracy performance, and the image quality of a mobile device camera against a full-frame mirrorless camera when used in close-range photogrammetry applications in various settings. Analytical methodologies and specialized digital tools are used to evaluate the results. In the end, generalized conclusions are drawn for using each technology in close-range photogrammetry applications.

Laser powder bed fusion (L-PBF) is widely used in automotive, aerospace, and biomedical applications thanks to its ability to produce complex geometries. In spite of its advantages, parts produced with this technology can show distortion due to the residual stresses developed during the printing process. For this reason, numerical simulations can be used to predict thermal gradients and residual stresses that can result in part distortion. Thus, instead of performing experimental tests and using a trial and error approach, it is possible to use numerical simulation to save time and material. In this work, the effect of laser power and scan speed on residual stress and part distortion was analysed using a commercial finite element analysis (FEA) software DEFORM-3D™ with a layer-by-layer approach. Moreover, the accuracy of the numerical model with respect to process parameters and the utilised mesh was also studied. The results obtained from the numerical simulation were compared to the actual distortions to evaluate the accuracy of the FEM model. The predicted distortions using FEM analysis well fit the trend of the measured ones. The accuracy of the numerical model increases by considering a finer mesh. [ABSTRACT FROM AUTHOR]

Findings on the specificity of dysfunctional beliefs for OCD are heterogeneous. A preliminary study using the Beliefs Questionnaire (BQ) showed that patients with OCD exhibit more overall dysfunctional beliefs compared to patients with depression, but only in two specific dysfunctional beliefs. Yet, evidence for this specificity in patients with OCD in comparison to anxious controls is still lacking. The present study aimed to investigate dysfunctional beliefs (as assessed by the revised version of the BQ; BQ-R) in an OCD sample compared to anxious controls. Eighty-five patients with OCD (without a comorbid diagnosis of an anxiety disorder; 61.2% female and M = 35.27 years of age [SD = 12.65]) were compared to 20 patients with anxiety disorder (without a comorbid diagnosis of OCD; 75.0% female and M = 32.45 years of age [SD = 11.23]) on the BQ-R. No differences were found on the BQ-R total score or its subscales between samples except for the subscale on depressive thinking pattern (d = 0.658), where the anxiety sample showed higher scores. However, exploratory analyses revealed higher values on specific items of the BQ-R for the OCD-sample. The present study was able to address the still missing comparison in dysfunctional beliefs of patients with OCD to patients with anxiety disorder. To conclude, the results indicate that core dysfunctional beliefs in OCD are shared with patients with anxiety disorder. The higher values on the subscale on depressive thinking patterns for anxious controls might reflect the more pronounced depressive symptomatology. [ABSTRACT FROM AUTHOR]

Abstract This article examines within-sector resource misallocation in three Southeast Asian countries—Indonesia, Malaysia, and Vietnam. The methodology accounts for measurement error in revenues and costs. The firm-level evidence suggests that measurement error is substantial, resulting in an overestimation of misallocation by as much as 30%. Nevertheless, resource misallocation across firms within a sector remains large, albeit declining. The findings imply that there are considerable potential gains from efficient reallocation—above 80% for Indonesia and around 20% to 30% for Malaysia and Vietnam. Private domestic firms and firms with higher productivity appear to face larger distortions that prevent them from expanding. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of welding sequences on residual stresses and distortions of welded components, using computational thermomechanical model-based finite element analysis (FEA). Residual stresses, a common outcome of welding, can cause material distortions and reduce product quality. We used FEA to simulate transient temperature fields generated during welding and evaluated their impact on the amplitude and distribution of residual stresses, the size of fusion and heat-affected zones, material microstructures, properties and fracture toughness. The study focused on an austenitic pipe butt junction, a commonly welded component in various industries. The identification of optimal welding sequences can minimize residual stresses and distortions, providing valuable insights for the development of efficient welding techniques, improved product quality, and reduced manufacturing costs. [ABSTRACT FROM AUTHOR]

Agency is central to remote actions, and it may enhance skills learning due to a partial overlap between brain structures and networks, the promotion of confidence towards a telemanipulator, and the feeling of congruence of the motor choice to the motor plan. We systematically reviewed studies aiming to verify the role of agency in improving learning. Fifteen studies were selected from MEDLINE and Scopus®. When a mismatch is introduced between observed and performed actions, the decrease in agency and learning is proportional to the intensity of the mismatch, which is due to greater interference with the motor programming. Thanks to multisensory integration, agency and learning benefit both from sensory and performance feedback and from the timing of feedback based on control at the goal level or the perceptual–motor level. This work constitutes a bedrock for professional teleoperation settings (e.g., robotic surgery), with particular reference to the role of agency in performing complex tasks with remote control.

The methods of nonlinear analysis allow a better structural design and more accurate answers in the verification of a structure, through which it is based on the linear analysis of the educational institution Héctor Rene Lanegra Romero; this has a current systemic structural configuration 780, which has been designed under the parameters of the E.030 standard. To know, verify and analyze the structural performance in which the educational institution is located, nonlinear static analysis was used; which consists of a Pushover analysis. The Pushover analysis allows us to calculate the seismic actions in structures where the elastic behavior of each element is observed, it also allows us to see the operational seismic performance in which the educational institution is located, through which capacity curves are obtained, generation of plastic ball joints and the verification of the point of performance of the building; which allows identifying if the said structure is active for a seismic signal. [ABSTRACT FROM AUTHOR]

A well‐known drawback with LCD‐displays in cold is a slow pixel response leading to poor picture quality. Low temperatures can constitute a hazard in viewing important displays in cars. Perceptual experiments with 20 test‐persons were conducted to find clear and acceptable ranges on screens simulating distortions in low temperatures. The results showed perception over clear and acceptable image quality was impaired beyond ‐20°C for the LCD‐screen in the experiments. [ABSTRACT FROM AUTHOR]

This paper proposes a neural networks predistorter based on the bidirectional long-short-term memory (BiLSTM) structure. The proposed predistorter was trained while ensuring that it captures the full intrinsic behavior of the device under test including its memory effects and nonlinear distortions. For this purpose, the device under test was characterized while operating at peak power level with a test signal that emulates strong memory effects. Extensive experimental validation carried on a commercial Gallium Nitride power amplifier prototype demonstrated the ability of the proposed predistorter to maintain standard compliant adjacent channel leakage ratio over a wide range of operating conditions including operating average power, signal bandwidth, and carriers’ configurations. It has been shown that a digital predistorter (DPD) derived from one single training condition was able to linearize the device under test for 72 different test conditions with signal bandwidths between 10MHz and 40MHz, and an operating power range of 5dB. Furthermore, benchmarking results showed that the BiLSTM DPD is unable to maintain satisfactory performance when trained with a sub-optimal signal which does not emulate the full behavior of the device under test. Moreover, it has been shown that the use of the optimal characterization signal along with a generalized memory polynomial predistorter does not lead to satisfactory performance. Hence, the resilience of the predistorter is obtained by combining the suitable model structure along with the appropriate training approach. Such resilient DPD presents a paradigm shift in predistortion techniques which significantly minimizes the need for update. It is anticipated that this work will pave the road for a new generation of DPDs resilient to a wide range of operating conditions.

Determination of lattice parameters from 3D electron diffraction (3D ED) data measured in a transmission electron microscope is hampered by a number of effects that seriously limit the achievable accuracy. The distortion of the diffraction patterns by the optical elements of the microscope is often the most severe problem. A thorough analysis of a number of experimental datasets shows that, in addition to the well known distortions, namely barrel-pincushion, spiral and elliptical, an additional distortion, dubbed parabolic, may be observed in the data. In precession electron diffraction data, the parabolic distortion leads to excitation-error-dependent shift and splitting of reflections. All distortions except for the elliptical distortion can be determined together with lattice parameters from a single 3D ED data set. However, the parameters of the elliptical distortion cannot be determined uniquely due to correlations with the lattice parameters. They can be determined and corrected either by making use of the known Laue class of the crystal or by combining data from two or more crystals. The 3D ED data can yield lattice parameter ratios with an accuracy of about 0.1% and angles with an accuracy better than 0.03°.

The article examines the current trends and features of US and EU protectionism towards Russia, its possible consequences and ways of response. Protectionism has been increasing since 2020, which is manifested in the intensification of the use of existing instruments and the development of the new ones.The article analyzes possible consequences of the spike in countervailing investigations by the US against Russia. The author highlights possible application of similar restrictive measures by other partners as an additional risk. An unprecedented event is the US Department of Commerce review of Russia’s status as a market economy country for purposes of antidumping duty investigations. Non-market economy status expands the capabilities of the US to “overcount” dumping and impose duties, thus impeding the activity of Russian companies on foreign markets. The US acknowledged for now that there does not exist a sufficient degree of evidence to justify a change in Russia’s market economy designation, nevertheless, one cannot rule out such attempts in the future.In the EU context, the practice of energy adjustments, which results in overstated production costs, normal value and anti-dumping duties for Russian goods, is continued. A new protectionist step is the publication of the report “On significant distortions in the economy of the Russian Federation for the purposes of trade defence investigations”, which lays an additional basis for the continuation and strengthening of restrictive measures. The article analyzes a new instrument of environmental protectionism, the EU’s carbon border adjustment mechanism, a levy on imported products based on the embedded CO2 emissions. The measure will affect important positions of the Russian exports – cement, electricity, fertilizers, iron & steel and aluminum. The mechanism can be considered an attempt to make up for the EU’s lack of natural competitive advantages in mineral raw materials and to impose its vision of economic policy goals on the rest of the world.In conclusion, the author highlights features of American and European protectionism towards Russia – active employment of the role of the state in the economy factor as well as environmental factor as pretexts for introducing or tightening restrictive measures.The main ways of Russia’s response to new challenges can be the use of the WTO platform in cooperation with other countries, the search for new economic levers in relations with the partners (including application of trade defence measures), the detection of possible market distortions in the EU and the US for possible use in EAEU investigations.

The digital era has become a lifesaver for the day to day activities of human beings. It has taken control in various areas ranging from capturing beautiful photographs to storing useful information. However, in olden days information was stored in written documents and preserved throughout. The documents stored may consist of information having historical or national importance. It is understood that, the documents cannot be preserved as such for a long period of time even though they are pristine collections. Therefore, it is necessary to restore the documents in order to safeguard the information in it for future without any distortions. Today, there are several methods for document restoration which helps to store the documents in digital means for future purpose. Meanwhile, the documents are of various types such as written documents, scanned printed text documents and so on. The restoration is a tedious process, as it involves removal of discolorations, insertion of missing texts, for restoring the document back to its original state. This paper emphasizes on restoration of scanned printed text document and word segmentation. The restoration of text images in computer vision gains more importance as the restored documents can be further utilized for character recognition or stored in digital libraries. The proposed approach is based on deep neural network, thresholding methods, binarization techniques and connected components. Deep neural network aids in the word segmentation process followed by thresholding methods. Further, the background of the document image is binarized using binarization technique and the distortions are removed using connected components. Various experiments are conducted on different images in order to demonstrate the proposed methodology. The experimental results show that the method outperforms the existing methodologies in the restoration of printed English text documents with varied noises to its original state. Henceforth, this method enhances the text readability without showing any traces of distortion. [ABSTRACT FROM AUTHOR]

Most existing renewables support schemes distort location and dispatch decisions. Many impose unnecessary risk on developers, increasing support costs. Efficient policy sets the right carbon price, supports capacity not output, ensures efficient dispatch and location. The EU bans priority dispatch and requires market-based bidding, but does not address the underlying problem that payment is conditional on generation, amplifying incentives to locate in windy/sunny sites. This article identifies the various distortions and proposes an auctioned contract to address location and dispatch distortions: a financial Contract for Difference (CfD) with hourly contracted volume proportional to local renewable output/MW, with a life specified in MWh/MW, with long-term transmission contracts based on predicted output-weighted actual or simulated nodal prices. This yardstick CfD delivers efficient dispatch. It assures but limits the total subsidy. It does not over-pay for windy/sunny sites. The revenue assurance allows high debt:equity, dramatically lowering the subsidy cost. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the work is a complex review of methods applied industrially as case hardening. The paper contains an overview of scientific and development works on surface case hardening methods, especially carburising and quenching, described in the literature from 2001-2020. Design/methodology/approach: State-of-the-art was reviewed by a critical review of the world literature published in 2001-2022, including theoretical work, scientific research, and industry reports. An additional examination of the state of the art was conducted in terms of patent works. Findings: The period of 2001-2020 was a time of intensive work on the modernisation of case hardening techniques to improve the repeatability and uniformity of the produced layers and minimise deformations after hardening. Developing computing technologies have played a large part in this progress. New technologies have also been developed. Research limitations/implications: The review of papers and patent databases was limited to databases providing English-language content options. Practical implications: Case hardening is a crucial stage of steel heat treatment in almost every industrial branch: mechanical, tool, automotive, railway, and aviation. Originality/value: A synthetic review of case hardening methods was presented, particularly carburizing and quenching methods; it also analysed the possibilities and directions of their development. conducted in terms of patent works. Findings: The period of 2001-2020 was a time of intensive work on the modernisation of case hardening improve the repeatability and uniformity of the produced layers and minimise deformations after hardening. computing technologies have played a large part in this progress. New technologies have also been developed. Research limitations/implications: The review of papers and patent databases was limited to databases Englishlanguage content options. Practical implications: Case hardening is a crucial stage of steel heat treatment in almost every industrial tool, automotive, railway, and aviation. Originality/value: A synthetic review of case hardening methods was presented, particularly carburizing methods; it also analysed the possibilities and directions of their development. Keywords. Heat treatment, hardening, quenching, distortions, carburizing, simulation Reference to this paper should be given in the following way: E. Wołowiec-Korecka, Case hardening development review (2001-2020). [ABSTRACT FROM AUTHOR]

Agent-based models (ABMs) often rely on psychometric constructs such as 'opinions', 'stubbornness', 'happiness', etc. The measurement process for these constructs is quite different from the one used in physics as there is no standardized unit of measurement for opinion or happiness. Consequently, measurements are usually affected by 'psychometric distortions,' which can substantially impact models' predictions. Even if distortions are well known in psychometrics, their existence and nature is obscure to many researchers outside this field. In this paper, we introduce distortions to the ABM community. Initially, we show where distortions come from and how to observe them in real-world data. We then show how they can strongly impact predictions, qualitative comparison with data and the problem they pose for validation of models. We conclude our analysis by discussing how researchers may mitigate this problem and highlight possible future modelling trends that will address this problem. [ABSTRACT FROM AUTHOR]

The wire arc additive manufacturing (WAAM) process is a 3D metal-printing technique that builds components by depositing beads of molten metal wire pool in a layer-by-layer style. Even though manufactured parts commonly suffer from defects, the search to minimize defects in the product is a continuing process, for instance, using modeling techniques. In areas where thermal energy is involved, thermomechanical modeling is one of the methods used to determine the input thermal load and its effect on the products. In the WAAM fabrication process, the thermal load is the most significant cause of residual stress due to the extension and shrinkage of the molten pool. This review article explores the thermomechanical effect and stress existing in WAAM-fabricated parts due to the thermal cycles and other parameters in the process. It focuses on thermomechanical modeling and analysis of residual stress, which has interdependence with the thermal cycle, mechanical response, and residual stress in the process during printing. This review also explores some methods for measuring and minimizing the residual stress during and after the printing process. Residual stress and distortion associated with many input and process parameters that are in complement to thermal cycles in the process are discussed. This review study concludes that the thermal dependency of material characterization and process integration for WAAM to produce structurally sound and defect-free parts remain central issues for future research. [ABSTRACT FROM AUTHOR]

Laser Powder Bed Fusion (LPBF) process is one of the advanced Additive Manufacturing (AM) processes, which is employed for the fabrication of complex metallic components. One of the major drawbacks of the LPBF is the development of residual stresses due to the high temperature gradients developed during the process thermal cycles. Reliable models for the prediction of residual strain and stress at part scale are required to support the LPBF process optimization. Due to the computational cost of the LPBF simulation, the current modelling methodology utilizes assumptions to make feasible the prediction of residual stresses at parts or component level. To this scope, a thermomechanical modelling approach for the simulation of LPBF process is presented with focus to residual stress and strain prediction. The modelling efficiency of the proposed approach was tested on a series on cases for which experimental data were available. The good comparison between the predicted and experimental data validated the modelling method. The efficiency of the thermomechanical modelling method is demonstrated by the reduced computational time required.

It has long been assumed that an accurate representation of the size and shape of one's body is necessary to successfully interact with the environment. Previous research has shown accurate representations when healthy participants make overt judgments (i.e. explicit) about the size of their bodies. However, when body size is judged implicitly, studies have shown systematic distortions. One suggestion for these differences, is that explicit and implicit representations are informed by different sensory modalities. Explicit representations rely on vision whereas implicit representations are informed by haptics. We designed an experiment to investigate if explicit representations that are informed by haptics are more like implicit representation featuring systematic distortions. We asked female participants to estimate the size of their fingers and hands in three different tasks: an explicit-haptic, an implicit, and an explicit-vision task. The results showed that all three representations were distorted and furthermore, the distortions for each representation were different from one another. These results suggest that inaccurate finger and hand length are a stereotypical feature of body representation that is present in both visual and haptic domains. We discuss the results in relation to theories of body representation. [ABSTRACT FROM AUTHOR]

We consider an extended two-stage risk-averse stochastic optimization problems in several formulations. Risk-aversion is reflected by risk constraints in form of stochastic-order relations, which are imposed in a time-consistent manner. The problem is analyzed under convexity assumptions. The main goal of this study is to establishing relations between the extended two-stage problem with stochastic-order constraints on the recourse function on the one hand and the two-stage problems with alternative models of risk such as utility functions, distortions, or coherent measures of risk on the other hand. [ABSTRACT FROM AUTHOR]

Copyright of Justitiële Verkenningen is the property of Boom uitgevers Den Haag and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Community Connections: Studies on Education, Culture / Közösségi Kapcsolódások: Tanulmányok Kultúráról és Oktatásról is the property of Szeged University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work addresses differences in predicted elastic fields created by dislocations either by the Phase Field Crystal (PFC) model, or by static Field Dislocation Mechanics (FDM). The PFC order parameter describes the topological content of the lattice, but it fails to correctly capture the elastic distortion. In contrast, static FDM correctly captures the latter but requires input about defect cores. The case of a dislocation dipole in two dimensional, isotropic, elastic medium is studied, and a weak coupling is introduced between the two models. The PFC model produces compact and stable dislocation cores, free of any singularity, i.e., diffuse. The PFC predicted dislocation density field (a measure of the topological defect content) is used as the source (input) for the static FDM problem. This coupling allows a critical analysis of the relative role played by configurational (from PFC) and elastic (from static FDM) fields in the theory, and of the consequences of the lack of elastic relaxation in the diffusive evolution of the PFC order parameter. • Algorithm coupling phase-field crystal (PFC) and field dislocation statics is proposed. • Elasto-static fields of a dislocation dipole predicted by both models are compared. • Dislocation cores rapidly stabilize giving correct elasto-static fields in far limit. • Configurational stresses equilibrate slowly due to lack of elastic relaxation in PFC. • Need for strong coupling between models is highlighted to study dislocation dynamics. [ABSTRACT FROM AUTHOR]

We examine empirically whether the level of data aggregation affects the assessment of misallocation in agriculture. Using data from Ugandan farmers, we document a substantial discrepancy between misallocation measures calculated at the plot and at the farm levels. Estimates of misallocation at the plot level are much higher than those obtained with the same data but aggregated at the farm level. Even after accounting for measurement error and unobserved heterogeneity, estimates of misallocation at the plot level are extremely high, with potential nationwide agricultural productivity gains of 562%. Furthermore, we find suggestive evidence that granular data may be more susceptible to measurement error in survey data and that data aggregation can attenuate the relative magnitude of measurement error in misallocation measures. Our findings suggest caution in generalizing insights on measurement error and misallocation from plot-level analysis to those at the farm level. • We assess whether the level of data aggregation matters when measuring misallocation. • Measures of misallocation with plot and farm-level data are not comparable. • Using plot-level data produces larger estimates of misallocation. • Plot-level estimates remain larger even after correcting for measurement error. • Caution is needed when extrapolating insights from plot-level analysis. [ABSTRACT FROM AUTHOR]

• Incorporation of Mg 2 Si as source material in vertical TFET enhances the electrical, RF, linearity and distortion performance metrics. • ON-state current (I ON) and current switching ratio (I ON /I OFF) for Mg 2 Si-VTFET improves by a factor of approximately ∼ 105 and 102 times. • HD2 suppresses by 53.8% for Mg 2 Si-VTFET over Si-VTFET, which suggests better linearity and distortion. • High cutoff frequency, GBP and smaller transit time of Mg 2 Si-VTFET shows better RF performance. This work investigates the performance of silicon-on-insulator (SOI) based vertical heterojunction tunnel FET with magnesium silicide (Mg 2 Si) as source material (Mg 2 Si-VTFET) with silicon-based counterpart (Si-VTFET). The investigation utilizes SILVACO TCAD tool to analyse various metrics including electrical characteristics, radio-frequency performance, linearity, and distortion. Incorporation of low bandgap material at source forms hetero-junction at source-channel interface, thereby reducing the tunneling path and enhancing the tunneling rate of charge carriers. ON-state current (I ON) and current switching ratio (I ON /I OFF) for Mg 2 Si-VTFET improves by factor of approximately ∼ 105 and 102 times. Mg 2 Si-VTFET outperforms Si-VTFET in terms of I ON current for low biasing voltages, transconductance (g m), gain-bandwidth-product (GBP), cut-off frequency (f T) and transit-time. However, Mg 2 Si-VTFET has better linearity and reduced distortions in terms of VIP2 and HD2 metrics. HD2 suppresses by 53.8 % for Mg 2 Si-VTFET over Si-VTFET. This suggests that Mg 2 Si-VTFET is better suited for applications requiring low distortion, such as in audio amplifiers or communication systems. Therefore, Mg 2 Si-VTFET shows strong candidacy over Si based counterpart for low power circuits. [ABSTRACT FROM AUTHOR]

Laser powder bed fusion (L-PBF) is widely used in automotive, aerospace, and biomedical applications thanks to its ability to produce complex geometries. In spite of its advantages, parts produced with this technology can show distortion due to the residual stresses developed during the printing process. For this reason, numerical simulations can be used to predict thermal gradients and residual stresses that can result in part distortion. Thus, instead of performing experimental tests and using a trial and error approach, it is possible to use numerical simulation to save time and material. In this work, the effect of laser power and scan speed on residual stress and part distortion was analysed using a commercial finite element analysis (FEA) software DEFORM-3D™ with a layer-by-layer approach. Moreover, the accuracy of the numerical model with respect to process parameters and the utilised mesh was also studied. The results obtained from the numerical simulation were compared to the actual distortions to evaluate the accuracy of the FEM model. The predicted distortions using FEM analysis well fit the trend of the measured ones. The accuracy of the numerical model increases by considering a finer mesh.