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Purpose: Industrial simulations of turbulent flows often rely on Reynolds-averaged Navier-Stokes (RANS) turbulence models, which contain numerous closure coefficients that need to be calibrated. This paper aims to address this issue by proposing a semi-automated calibration of these coefficients using a new framework (referred to as turbo-RANS) based on Bayesian optimization. Design/methodology/approach: The authors introduce the generalized error and default coefficient preference (GEDCP) objective function, which can be used with integral, sparse or dense reference data for the purpose of calibrating RANS turbulence closure model coefficients. Then, the authors describe a Bayesian optimization-based algorithm for conducting the calibration of these model coefficients. An in-depth hyperparameter tuning study is conducted to recommend efficient settings for the turbo-RANS optimization procedure. Findings: The authors demonstrate that the performance of the k-ω shear stress transport (SST) and generalized k-ω (GEKO) turbulence models can be efficiently improved via turbo-RANS, for three example cases: predicting the lift coefficient of an airfoil; predicting the velocity and turbulent kinetic energy fields for a separated flow; and, predicting the wall pressure coefficient distribution for flow through a converging-diverging channel. Originality/value: To the best of the authors' knowledge, this work is the first to propose and provide an open-source black-box calibration procedure for turbulence model coefficients based on Bayesian optimization. The authors propose a data-flexible objective function for the calibration target. The open-source implementation of the turbo-RANS framework includes OpenFOAM, Ansys Fluent, STAR-CCM+ and solver-agnostic templates for user application. [ABSTRACT FROM AUTHOR]

To price exotic foreign exchange (FX) options, a model needs to be selected for FX spot rate dynamics. The classic approach of modelling spot rates with Black–Scholes framework makes inappropriate assumptions of constant drift and volatility, resulting in mispricing. In this article, we investigate multi-regime Black–Scholes (MRBS) model for FX rate, with regime-switching behaviour of drift and volatility governed by a Markov chain. We derive an analytic formula for European FX call options via Fourier transform and present a Monte Carlo simulation algorithm for FX barrier option pricing. Further, we propose a calibration strategy with penalty. Finally, the empirical study shows that volatility smile can be recovered by MRBS model; calibrating MRBS with penalty gives stable calibrated parameters and small out-of-sample mean squared errors; combined use of our calibration methods and pricing algorithms provides reasonable prices for FX barrier options. Thus, MRBS model, together with proposed calibration-with-penalty strategy and pricing algorithm, provides a promising approach for FX option pricing. • Multi-regime Black–Scholes foreign exchange (FX) model recovers stylised market facts. • Vanilla FX option price formula is derived and used for calibration to real-time data. • Proposed calibration-with-penalty strategy leads to more financially realistic models. • A pricing engine is developed for FX barrier options under multi-regime model. [ABSTRACT FROM AUTHOR]

This article discusses calibration metrics in the context of cannabis analysis. It explains the concept of variance and how it is measured, using illustrations and equations. The article also introduces the standard deviation as a measure of accuracy and explains how to calculate it. Additionally, it discusses the correlation coefficient, which measures the correlation between actual and predicted values, and the F for Regression, which measures the robustness of a calibration. The article concludes by emphasizing the importance of calibration metrics in assessing the quality of analytical instruments. [Extracted from the article]

The article evaluates the Common-Mode Current Test Rig from Halibut Electronics, which simplifies the process of testing common-mode chokes by providing quick and easy calibrations using onboard switches.

This article discusses the process of creating calibration lines and calculating correlation coefficients in calibration science. It uses the example of measuring the amount of isopropyl alcohol (IPA) dissolved in water using mid-infrared spectroscopy. The article explains how calibration lines are two-dimensional mathematical models that relate two sets of data, and how the correlation coefficient measures the linearity of the relationship between the data sets. It also emphasizes the importance of using calibration lines only within the range of calibration data. The article provides examples and equations to illustrate these concepts. [Extracted from the article]

This article discusses calibration science in the context of cannabis analysis. It introduces the concept of systematic error, which is a type of error that consistently affects measurements in the same direction. The article explains how accuracy measures both systematic and random errors, and discusses how to quantitate error by measuring signal-to-noise ratios. It also explores methods to reduce random noise by averaging multiple observations together. The article emphasizes the importance of precision, accuracy, and data quality in cannabis analysis. [Extracted from the article]

Calibration meetings, which are intended to eliminate bias in performance evaluations, can actually introduce bias into the process. While these meetings are successful at reducing leniency bias, they tend to rank employees more towards the middle of the scale, failing to differentiate between high, average, and low performers. Consensus evaluations in law firms, where a small group of partners calibrate supervisor evaluations, can reinforce gender and racial stereotypes. Unstructured calibration meetings can also lead to bias, as certain employees may receive more airtime or be judged on different criteria. However, small tweaks such as training participants to recognize bias, using a consistent performance rubric, and assigning people to look for bias during the meeting can help interrupt bias and create a fair evaluation process. [Extracted from the article]

This article discusses the importance of successful calibration for advanced driver-assistance systems (ADAS) in vehicles. The author emphasizes the need to consult the original equipment manufacturer (OEM) service information for each specific vehicle, as the calibration process can vary. Factors such as software, equipment, vehicle setup, and environment all play a crucial role in ensuring accurate calibration. The article also highlights the challenges and considerations involved in creating the correct environment for calibrations, as well as the ongoing need for technicians and shops to stay updated and trained on calibration procedures. [Extracted from the article]

The development of an accurate rock discrete element model is essential for modeling core drilling in the lunar environment. However, most of the microscopic parameters of the discrete element model cannot be determined directly by tests. Consequently, a rapid calibration method for microscopic parameters was developed, combining an approximation model, multiple objectives with particle swarm optimization algorithm (MOPSO), and orthogonal experimental design (OED). Range analysis and variance analysis were conducted to investigate the sensitivity of these parameters. Through this approach, the optimal solution for microscopic parameters was obtained to align with the mechanical characteristics of lunar rock simulant, providing a foundation for rock core drilling. The results demonstrate a high level of agreement between the simulated stress-strain curves and the test results. The deviation between the mechanical strength parameters and actual test values was found to be less than 5%, confirming the effectiveness and rationality of the proposed parameter calibration method. This method holds significant potential for widespread application in calibrating the parameters of discrete element models for rock materials. [ABSTRACT FROM AUTHOR]

The article focuses on the introduction of new measurement units in LuaMetaTeX, such as the Edith (es) and Tove (ts) units, which are proposed as alternatives to the traditional Knuth (dk) unit. Topics include the need for more gender-neutral and metric units in typography and typesetting, the calibration process for these units, and the aim to replace existing units such as the inch, bringing a fresh perspective to measurement standards.

The document titled "Shutterclucks" is a column in Chickens magazine that features the winners of a photo contest. The winners, who are from various locations in the United States, submitted pictures of their chickens. The article also mentions a prize for the winner, which is a ChickSafe Eco Coop Opener from Brinsea. The contest is open to legal residents of the United States who are 21 years or older. The article provides information on how to enter the contest and includes the official rules. [Extracted from the article]

In this paper, we consider the pricing of American options under a regime-switching double Heston model, such that the interest rate and mean-reversion level parameters in both stochastic volatility models shift in various states. We develop a semi-analytical formula for double Heston partial differential equation by using the equivalent European put option price and standard portfolio-consumption model. Then through the moment-generating function of this particular model, the American put option price is evaluated. We employ the Levenberg–Marquardt optimization method to calibrate the regime-switching double Heston model. Numerical experiments have also been performed to demonstrate the accuracy of the proposed formula and the performance of regime change mechanism on option pricing. Ultimately, through an experimental application, we indicate the proposed model is premier to the double Heston model, which illustrates the importance of considering regime-switching factor. [ABSTRACT FROM AUTHOR]

Copyright of Vision Mobility is the property of Huss Verlag GmbH 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 paper presents a novel static digital pre-distortion (DPD) method for a current-steering digital-to-analog converter (CS-DAC). The proposed method utilizes the knowledge of the current cell array architecture to calculate the static mismatch currents of the cells. The mismatch values are stored in memory and added to the original input code to generate the new pre-distorted input word. The converter corrects the static error with its own current cells without incorporating an additional calibration DAC (CALDAC) or programmable current sources. This results in a reduction in area, power and simulation run times because of the simpler circuit design. An Overflow-Cell-Selection (OCS) is introduced as a novel solution to further enhance the static linearity of the converter. It also can be implemented as a software solution for already existing DAC designs which do not have an integrated DPD and lab/measurement equipment (e.g., arbitrary wave generator (AWG)). This poses as a strong differentiation factor compared to other state-of-the-art static DPD methods. The evaluation of the proposed DPD is done via simulations in MATLAB and on- chip measurements with a 14-bit CS-DAC in 16 nm. Single tone measurements show a performance gain of the total harmonic distortion (THD) of 12 dB. [ABSTRACT FROM AUTHOR]

This paper presents a high-current calibration-free analog-digital hybrid controlled LDO for large-area digital load. The proposed architecture has the advantages of an analog controller (continuous and high DC accuracy) with distributed digital power transistors (flexible and scalable for high current applications). Distinctive from the conventional digital LDOs that directly quantize the output voltage, the proposed LDO utilizes an error amplifier (EA) to pre-amplify the $\text{V}_{\mathrm {OUT}}$ error. Then, a 5-bit time-to-digital converter (TDC) quantizes the processed analog error signal subsequently transformed into a thermometer code that directly controls the distributed digital power transistors. This design can pull off high DC accuracy even without calibration. Besides, we implement an auxiliary constant current (ACC) circuit to solve reliability issues and to improve the stability under a large voltage dropout. Fabricated in a 28-nm bulk CMOS process with a 1.2-A load capability, the proposed LDO achieves 2- $\mu \text{V}$ /mA load regulation and close to 1.5% output accuracy. By employing a wide bandwidth EA and a fast TDC, the hybrid LDO can obtain a fast transient response. The measured undershoot is 70 mV with a 0.6-A load step within 10-ns edge time, and the output voltage can scale from 0.6 V to 0.9 V within 30 ns. [ABSTRACT FROM AUTHOR]

This work presents analysis and calibration of interleaving and data timing errors that are encountered in modern times-2 interleaved digital-to-analog converters (DACs) with a current-steering (CS) architecture. Such errors corrupt the DAC output spectrum with spectral images that require calibration. We develop an analytical model for the interleaving and data timing errors that we understand are most significant and propose a calibration algorithm that treats all of them. Extensive simulations of the algorithm are made possible by leveraging the speed and accuracy of the analytical model. The algorithm is demonstrated on a commercially-developed 10-bit times-2 interleaved CS-DAC, operating at 40GS/s in 14nm CMOS. [ABSTRACT FROM AUTHOR]

This paper presents a 1.5-GS/s 6-bit single-channel loop-unrolled successive approximation register (SAR) analog-to-digital converter (ADC) using speculative capacitive DAC (CDAC) switching control technique. The proposed SAR ADC achieves a high sampling rate by eliminating additional delays in typical loop-unrolled SAR ADCs related to settling time constraints in their CDACs. Specifically, the CDACs are duplicated and controlled in speculative ways so that the CDAC outputs passage to their next values before completing the regeneration operation of comparators, thereby improving timing constraints for successive approximations. The switching power overhead from the CDAC speculation is mitigated by introducing an energy-efficient CDAC control technique that produces desired voltage transients with minimal power overheads. The prototype of the proposed SAR ADC is fabricated in a 28-nm CMOS technology and occupies an active area of 0.0038-mm2. The design consumes 5.8 mW from a 1.2-V supply. The ADC achieves 1.5-GS/s sampling frequency with a 31-dB SNDR at a low input frequency and a 28.6 dB at the Nyquist frequency without applying any offset calibration techniques, achieving the highest sampling frequency among the 6-bit single-channel loop-unrolled SAR ADCs reported. [ABSTRACT FROM AUTHOR]

In a regression setup, we study in this brief the performance of Gaussian empirical gain maximization (EGM), which includes a broad variety of well-established robust estimation approaches. In particular, we conduct a refined learning theory analysis for Gaussian EGM, investigate its regression calibration properties, and develop improved convergence rates in the presence of heavy-tailed noise. To achieve these purposes, we first introduce a new weak moment condition that could accommodate the cases where the noise distribution may be heavy-tailed. Based on the moment condition, we then develop a novel comparison theorem that can be used to characterize the regression calibration properties of Gaussian EGM. It also plays an essential role in deriving improved convergence rates. Therefore, the present study broadens our theoretical understanding of Gaussian EGM. [ABSTRACT FROM AUTHOR]

Time-series classification approaches based on deep neural networks easily overfit UCR datasets, which is caused by the few-shot problem of those datasets. Therefore, to alleviate the overfitting phenomenon to further improve accuracy, we first propose label smoothing for InceptionTime (LSTime), which adopts the soft label information compared to only hard labels. Next, instead of manually adjusting soft labels by LSTime, knowledge distillation for InceptionTime (KDTime) is proposed to automatically generate soft labels by the teacher model while compressing the inference model. Finally, to rectify the incorrectly predicted soft labels from the teacher model, knowledge distillation with calibration for InceptionTime (KDCTime) is proposed, which contains two optional calibrating strategies, i.e., KDC by translating (KDCT) and KDC by reordering (KDCR). The experimental results show that the KDCTime accuracy is promising, while its inference time is orders of magnitude faster than state-of-the-art approaches. [ABSTRACT FROM AUTHOR]

The article provides information on a patent application for manual calibration of imaging systems filed by the inventors Andreas Johansson and Jason Y. Sproul on February 6, 2024 and made available online on August 29, 2024. It discusses time-of-flight imaging technologies in medicine and other fields, inventors' summary information for the patent application, and the claims supplied by the inventors.

The article reports on a joint venture agreement by International Isotopes, Inc. and Phantech Medical to form PhanQual, which will design, manufacture, and distribute calibration and reference sources for pre-clinical applications. Topics include the commitment by International Isotopes team to serving the medical imaging community and improving healthcare, comments from Justin Jeffery of Phantech, and the next step in making RadQual the global leader in all calibration and reference sources.

Copyright of AutomotiveIT is the property of Media-Manufaktur GmbH 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 paper investigates differential privacy Kalman filtering for graphical dynamic systems. An enhanced differential privacy Kalman filter is initially developed by leveraging the topology, a unique characteristic of graphical dynamic systems, to improve the filtering performance. And then upper and lower error bounds of the enhanced filter are established to evaluate the recipient's ability to infer sensitive data. Based on these error bounds, a privacy calibration guideline is provided to balance privacy and usability of sensitive data. A notable feature of the enhanced filter is that its Kalman gain matrix is a diagonal matrix, which facilitates the independent update of information at each node by reducing the coupling between nodes. This feature diminishes the accumulation of filtering errors, thereby improving the data availability for the recipient. Finally, the effectiveness of the proposed approach is verified through a simulation of epidemiological data analysis, and the results show that the enhanced filter performs well in systems with high privacy levels. [ABSTRACT FROM AUTHOR]

The article focuses on a patent application for a new calibration system designed for spectroscopic devices. Topics include the development of calibration techniques for optical sensors, the use of electronic processes for device standardization, and the application of these methods to improve diagnostic accuracy in medical settings.

The article discusses a newly submitted patent application for a "Calibration Phantom, Method, and System" designed to improve the accuracy of radiotherapy imaging systems. It states that this patent, filed by Markus Eriksson and Joakim Sebastian da Silva, introduces an innovative calibration phantom with multiple boards arranged to face different directions, which enhances the calibration of imaging scanners and accounts for mechanical flexing during gantry rotation.

The document titled "MELLab MYc-3 Measurement Microphones" provides information about the features and specifications of the MYc-3 measurement microphone. Designed for P.A. system optimization, this professional omnidirectional microphone offers linear, low-distortion performance with a free-field frequency response between 10 and 20,000 Hz. It has a THD of approximately 1% at 130 dB SPL and comes with a response correction file and calibration chart. The microphone is available for purchase individually or in matched pairs, triples, and quads. [Extracted from the article]

Researchers from Goethe-University Frankfurt in Germany have conducted a study on the performance of the Optimized Hierarchical Two-parameter Logistic IRT Model (OH2PL) in small-sample item calibration. The study found that the OH2PL model yielded unbiased parameter estimates and outperformed other estimation methods in terms of item discrimination parameters. The researchers discuss the implications of these findings for the application of complex IRT models in small-scale psychological research. The study has been peer-reviewed and published in Behavior Research Methods. [Extracted from the article]

LG Electronics Inc. has been issued a patent for a method and apparatus for performing power calibration in a wireless power transfer system. The wireless power transfer technology allows for the wireless transfer of power between a power source and an electronic device, providing convenience and mobility. However, there can be errors in the power transfer due to changes in magnetic coupling and usage environments. This patent aims to address these issues by providing a method for calibrating transmitted power and reception power, as well as performing foreign object detection. [Extracted from the article]

A report from the University of Geneva discusses the need for reliable analytical methodologies to assess the ecological and environmental consequences of neonicotinoids, a class of insecticides that have been identified as a major concern for biodiversity. The researchers compared the performance of internal calibration (IC) and classical multipoint external calibration (EC) for quantifying neonicotinoids in honey. They found that IC showed acceptable levels of trueness and precision, although slight biases were observed at very low concentrations compared to EC. The study suggests that implementing IC could simplify quantification in liquid chromatography-mass spectrometry-based pesticide applications. [Extracted from the article]

A recent study conducted by the Bill and Melinda Gates Foundation has found that human papillomavirus (HPV) is responsible for nearly all cases of cervical cancer, which claims the lives of approximately 340,000 women annually. The research aimed to understand the natural history of HPV and its progression to cervical cancer. By creating models for the 30 most populous countries in Sub-Saharan Africa, the study revealed that variations in host immune responses may contribute to the differences in cervical cancer burden between countries. The findings highlight the importance of collecting geographically diverse data to further comprehend the natural history of HPV. [Extracted from the article]

A patent has been issued for a catheter with serially connected sensing structures and methods of calibration and detection. The catheter is designed for diagnostic and therapeutic techniques, such as intracardiac radio-frequency ablation. It includes magnetic position sensors for determining the position coordinates of the catheter, as well as pressure sensors for detecting pressure exerted on the distal end of the catheter. The invention aims to reduce the number of leads used in the catheter, improve sensing capabilities, and minimize lead breakage and failure. The patent was filed by Biosense Webster (Israel) Ltd. [Extracted from the article]

A patent has been issued to Claronav Inc. for a surgical tool calibration system. The system uses a calibrated imaging device to capture images of the surgical tool's surface and maps the 2D locations in the images to a 3D coordinate frame. The system then determines the location of a point of interest (POI) on the tool based on the image and the mapping. This method eliminates the need for a separate calibration device and allows for accurate calibration of various types of surgical tools. [Extracted from the article]

Covidien LP has been issued a patent for a system and method for controlling an electrosurgical generator. The system allows for independent control of multiple monopolar electrosurgical devices that share a common return path through one or more return electrodes. The system includes an electrosurgical generator with two radio frequency channels, each generated by a separate RF source, and each source is controlled by its own controller. The system also includes a calibration assembly that measures electrical properties in response to the radio frequency waveforms. This patent addresses the need for simultaneous RF monopolar calibration using a shared return electrode, providing a more efficient and cost-effective solution for dual site surgery. [Extracted from the article]

A recent study conducted at Children's Hospital Philadelphia has provided updated information on bladder exstrophy, a congenital abnormality. The study focused on the assessment of pubic diastasis, which is important for surgical planning in patients with bladder exstrophy-epispadias complex. The researchers used imaging phantoms to evaluate the effect of radiographic calibration on measurements of pubic diastasis and found that image calibration resulted in more accurate and uniform measurements. While small differences in the pelvic ratio may not be clinically significant, image calibration may still be prudent. This research has been peer-reviewed and published in Pediatric Radiology. [Extracted from the article]

This patent application describes a method and system for calibrating a C-arm imaging device used in surgical navigation. The method involves determining the angulation and orbital values of the device at different positions, capturing images of a calibration fixture, and using a tracking system to determine the position of the fixture and a tracking array on the device. Intrinsic and extrinsic parameters of the device are then determined, and a model is generated based on these parameters. The model can be used to render surgical instruments in medical images. The system includes a calibration fixture, a tracking array, a tracking device, and a C-arm calibration device with processors and memory. The model can be updated periodically. [Extracted from the article]