- document
-
Visser, P.N.A.M. (author)A method has been developed and tested for estimating calibration parameters for the six accelerometers on board the Gravity field and steady-state Ocean Circulation Explorer (GOCE) from star tracker observations. These six accelerometers are part of the gradiometer, which is the prime instrument on board GOCE. It will be shown that by taking...journal article 2008
- document
-
Bouman, J. (author), Rispens, S. (author), Gruber, T. (author), Koop, R. (author), Schrama, E. (author), Visser, P. (author), Tscherning, C.C. (author), Veicherts, M. (author)One of the products derived from the gravity field and steady-state ocean circulation explorer (GOCE) observations are the gravity gradients. These gravity gradients are provided in the gradiometer reference frame (GRF) and are calibrated in-flight using satellite shaking and star sensor data. To use these gravity gradients for application in...journal article 2008
- document
-
Visser, P.N.A.M. (author)A method has been implemented and tested for estimating bias and scale factor parameters for all six individual accelerometers that will fly on-board of GOCE and together form the so-called gradiometer. The method is based on inclusion of the individual accelerometer observations in precise orbit determinations, opposed to the baseline method...journal article 2008
- document
-
Benmahdjoub, Mohamed (author), Niessen, W.J. (author), Wolvius, Eppo B. (author), van Walsum, T. (author)Augmented reality (AR) permits the visualization of pre-operative data in the surgical field of view of the surgeon. This requires the alignment of the AR device’s coordinate system with the used navigation/tracking system. We propose a multimodal marker approach to align an AR device with a tracking system: in our implementation, an...journal article 2022
- document
-
Domhof, J.F.M. (author), Kooij, J.F.P. (author), Gavrila, D. (author)We address joint extrinsic calibration of lidar, camera and radar sensors. To simplify calibration, we propose a single calibration target design for all three modalities, and implement our approach in an open-source tool with bindings to Robot Operating System (ROS). Our tool features three optimization configurations, namely using error...journal article 2021
- document
-
Chen, Y. (author), Gong, J. (author), Staszewski, R.B. (author), Babaie, M. (author)In this article, we present a 4.5-5.1-GHz fractional-N digitally intensive phase-locked loop (DPLL) capable of maintaining its performance in face of a large supply ripple, thus enabling a direct connection to a switched-mode dc-dc converter. Supply pushing of its inductor-capacitor (LC) oscillator is suppressed by properly replicating the...journal article 2022
- document
-
Gong, J. (author), Chen, Y. (author), Charbon-Iwasaki-Charbon, E. (author), Sebastiano, F. (author), Babaie, M. (author)This article presents a 4-to-5GHz LC oscillator operating at 4.2K for quantum computing applications. The phase noise (PN) specification of the oscillator is derived based on the control fidelity for a single-qubit operation. To reveal the substantial gap between the theoretical predictions and measurement results at cryogenic temperatures, a...journal article 2022
- document
-
Xie, S. (author), Abarca Prouza, A.N. (author), Theuwissen, A.J.P.A.M. (author)This brief proposes employing each of the classical 4 transistor (4T) pinned photodiode (PPD) CMOS image sensor (CIS) pixels, for both imaging and temperature measurement, intended for compensating the CISs' dark current, and dark signal non-uniformity (DSNU). The proposed temperature sensors rely on the thermal behavior of MOSFETs working in...journal article 2020
- document
-
Pan, S. (author), Angevare, J. (author), Makinwa, K.A.A. (author)This article describes a hybrid temperature sensor in which an accurate, but energy-inefficient, thermal diffusivity (TD) sensor is used to calibrate an inaccurate, but efficient, resistor-based sensor. The latter is based on silicided polysilicon resistors embedded in a Wien-bridge (WB) filter, while the former is based on an electrothermal...journal article 2021
- document
-
Pourmousavian, Naser (author), Kuo, Feng Wei (author), Siriburanon, Teerachot (author), Babaie, M. (author), Staszewski, R.B. (author)This paper proposes an ultra-low-voltage (ULV) fractional-N all-digital PLL (ADPLL) powered from a single 0.5-V supply. While its digitally controlled oscillator (DCO) runs directly at 0.5 V, an internal switched-capacitor dc-dc converter ``doubles'' the supply voltage to all the digital circuitry and particularly regulates the time-to...journal article 2018
- document
-
Guo, Y. (author), Jia, W. (author), Markine, V.L. (author), Jing, Guoqing (author)Ballast rheology is a phenomenon that describes movements of ballast particles due to the discrete nature, which eventually leads to the ballast bed fluid deformation after a long-time service. In most cases, ballast rheology is the main reason of track irregularity that leads to some track defects, e.g., hanging sleeper and mud spots....journal article 2021
- document
-
Yan, Y. (author), Helmons, R.L.J. (author), Wheeler, Craig (author), Schott, D.L. (author)A previous study revealed that a convex pattern surface can reduce sliding wear of a transfer chute. A convex pattern surface is a flat surface outfitted with a pattern of convexes defined by five parameters. A three-level definitive screening design (DSD) method combined with discrete element method (DEM) is used to investigate the influence...journal article 2021
- document
-
Suzuki, T. (author), García-Feal, Orlando (author), Domínguez, José M. (author), Altomare, Corrado (author)Ongoing climate change is a significant threat to coastal communities. To understand potential risks during extreme storm events, detailed post-overtopping processes are investigated using DualSPHysics and SWASH with a newly developed approach. It is a calibrated-based wave generation: a target incident wave is first obtained from the...journal article 2022
- document
-
Cheruiyot, Elijah (author), Mito, Collins (author), Menenti, M. (author)This work presents an improved gravimetric algorithm to derive reference soil moisture, with removal of some of the hypothesis on which its original expression was based, and addition of a new corrective term that takes into account the interdependence between temperature and non-unitary water density. The temperature correction term improves...journal article 2023
- document
-
Mier Escurra, C. (author), Mor, A. R. (author), Vaessen, P.T.M. (author)This paper introduces a directional coupler for partial discharge (PD) measurements in gas-insulated substations (GIS). The sensor comprises a combination of magnetic and electric couplers, effectively segregating forward and backward pulses to enhance PD charge estimation and defect location. The sensor's design was supported with finite...journal article 2024
- document
-
Adla, Soham (author), Bruckmaier, Felix (author), Arias-Rodriguez, Leonardo F. (author), Tripathi, Shivam (author), Pande, S. (author), Disse, Markus (author)Sensor data and agro-hydrological modeling have been combined to improve irrigation management. Crop water models simulating crop growth and production in response to the soil-water environment need to be parsimonious in terms of structure, inputs and parameters to be applied in data scarce regions. Irrigation management using soil moisture...journal article 2024
- document
-
Kok, G. (author), Pelevic, N. (author), Chiribiri, A. (author), Milidonis, X. (author), Nazir, M. (author), Capstick, M. (author), Drost, S. (author), Poelma, C. (author), Schaeffter, T. (author)In the medical sector, various imaging methodologies or modalities (e.g. MRI, PET, CT) are used to assess the health of various parts of the bodies of patients. One such investigation is the blood flow or perfusion of the heart muscle, expressed as the (blood) flow rate normalized by the mass of the volume of interest. Currently there is no...journal article 2021
- document
-
di Biase, V. (author), Hanssen, R.F. (author), Vos, S.E. (author)Anthropogenic activities and climate change in coastal areas require continuous monitoring for a better understanding of environmental evolution and for the implementation of protection strate-gies. Surface moisture is one of the important drivers of coastal variability because it highly affects shoreward sand transport via aeolian processes....journal article 2021
- document
-
Galatro, L. (author), Spirito, M. (author)In this paper, we propose a method based on 3-D electromagnetic simulations, for the characteristic impedance extraction of transmission lines employed in TRL calibration, focusing on lines integrated in silicon technologies. The accuracy achieved with TRL calibrations using the proposed characteristic impedance extraction is benchmarked...journal article 2017
- document
-
Ramamohan, Krishnaprasad Nambur (author), Chepuri, Sundeep Prabhakar (author), Comesana, Daniel Fernandez (author), Leus, G.J.T. (author)In this work, we consider the self-calibration problem of joint calibration and direction-of-Arrival (DOA) estimation using acoustic sensor arrays. Unlike many previous iterative approaches, we propose solvers that can be readily used for both linear and non-linear arrays for jointly estimating the sensor gain, phase errors, and the source...journal article 2023