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Regarding the low accuracy and instability of common online methods for estimating dynamic models in the time domain, in the presence of uncertainty in system dynamics, sensor noise and environmental disturbances, this area is still open for further research. In this paper, a new estimation method is proposed based on a new online robust meta‐heuristic adaptive LSQR (ORALSQR) for simultaneous estimation of a multi input/output linear dynamic model and system state variables. This new adaptive LSQR algorithm is used to solve the output matrix equations of the least squares error problem. The presented algorithm, based on its iterative nature, searches the answer subspace by using a new meta‐heuristic logic. In addition, the algorithm solving steps and the search domain size in each iteration are intelligently determined by the method. In an identification maneuver, this method estimates the state variables using an estimated model in the Kalman filter, then estimates the model online for the next iteration using the state variables. In addition the stability proof of this method is presented. Numerical results show more accuracy and robustness of this method compared to the other methods mentioned in this paper which contain LS and RLS based estimation methods. Regarding the low accuracy and instability of common online methods for estimating dynamic models in the time domain, in the presence of uncertainty in system dynamics, sensor noise and environmental disturbances, this area is still open for further research. In this paper, a new estimation method is proposed based on a new online robust meta‐heuristic adaptive LSQR for simultaneous estimation of a multi input/output linear dynamic model and system state variables. The adaptive LSQR algorithm is used to solve the output matrix equations of the least squares error problem. The presented algorithm, based on its iterative nature, searches the answer subspace by using a new meta‐heuristic logic. In addition, the algorithm solving steps in each iteration and search domain are intelligently determined by the method. In an identification maneuver, this method estimates the state variables using an estimated model in the Kalman filter, then estimates the model online for the next iteration using the state variables. Numerical results show more accuracy and better performance of this method compared to the other mentioned methods in this paper.

Purpose – The purpose of this paper is to perform a comparative study of two propagation models and a prediction of proximity distances among the space objects based on the two-line element set (TLEs) data, which identifies potentially risky approaches and is used to compute the probability of collision among the spacecrafts. Design/methodology/approach – At first, the proximities are estimated for the mentioned satellites using a precise propagation model and based on a one-month simulation. Then, a study is performed to determine the probability of collision between two satellites using a formulation which takes into account the object sizes, covariance data and the relative distance at the point of closest approach. Simplifying assumptions such as a linear relative motion and normally distributed position uncertainties at the predicted closest approach time are applied in estimation. Findings – For the case of Iridium-Cosmos collision and the prediction of a closest approach using available TLE orbital data and a propagation model which takes into account the effects of the earth’s zonal harmonics and drag atmospheric, the maximum probability of about 2 × 10 −6 was obtained, which can indicate the necessity of enacting avoidance maneuvers regarding the defined a probability threshold by satellite’s owner. Originality/value – The contribution of this paper is to analyze and simulate the 2009 prominent collision between the Cosmos2251 and Iridium33 satellite by modeling their orbit propagation, predicting their closest approaches and, finally, assessing the risk of the possible collision. Moreover, an enhanced orbit determination can be effective to achieve an accurate assessment of the ongoing collision threat to active spacecrafts from orbital debris and preventing, if necessary, the hazards thereof.

Congenital heart diseses, are chronic illness in infants & children. This research is a quasi-exprimental study investigating the impact of education on home care knowledge of sixty mothers with children undergoing heart surgery. Data collection consisted of a pretest, posttest and retentional questionnaire that contain of demographic data of mother & her baby and multiple choice test relate to heart diseases, surgical treatment, complication and home care of babies. The mothers gained a positive mark for true answer, a negative mark for a false answer and a zero mark for an unknown answer. Data collection was conducted in before admission of babies, one week and one month after discharge. As for the case group teaching programs consisted of educational vido films and a face to face teaching and educational booklet. For the data analysis a spss package & descriptive statistic were employed. To identify the level of mother's knowledge, mother's mark were classified as, good-moderate and weak. The result obtained showed that at pretest. the subjects in the case group did not have a good level. As for the control group only 6.7% were evaluated as good level at pretest. At posttest and retentional phases scors increased to 100 and 96.7% respectively for the case group. Regarding the control group 6.7% were evaluated as good and dropped to zero at the retentional stage. However, comparsion of the mean score at the posttest and retentional in both groups, showed a a decrease of knowledge overtime. In conclusion the results of the present study significantly supports the impact of education on improving the knowledge of mothers on providing a better home care for children undergoing heart surgery.

This study considers blood flow in total cavopulmonary connection (TCPC) morphology created in Fontan surgical procedure in patients with a single ventricle heart disease. An ordinary process of TCPC operation reduces pulmonary blood flow pulsatility since the right ventricle being bypassed. This reduction may limit the long term outcome of Fontan circulation. There is an idea of increasing pulmonary flow pulsations by keeping Main Pulmonary Artery (MPA) partially open while it was closed in ordinary TCPC operation. The purpose of the present study is to verify the effects of Antegrade Flow (AF) coming through stenosed MPA on pulmonary flow pulsations. The 3D geometry is reconstructed from CT angiography scan of a patient who has undergone an ordinary TCPC procedure. The results show that adding AF increases Pulsatility Index (PI) in both Left and Right Pulmonary Artery (LPA and RPA respectively). Moreover, adding AF leads to an increase in energy loss. It also increases the pulmonary-to-systemic flow ratio leading to increase in total cardiac flow rate and hence heart power.

The near-infrared Calcium II Triplet (CaT), around 850nm, is a key metallicity indicator for red giant stars. We present a revised [Fe/H] calibration as a function of CaT line strengths and four luminosity indicators, including the \\(Gaia\\) \\(G\\)-band, together with the classical \\(V\\), \\(I\\), and \\(K_s\\) bandpasses. For this purpose, we used a sample of 366 red giant stars belonging to 25 globular and open clusters, complemented by 52 extremely metal-poor field giant stars. The CaT line strengths are determined by fitting Gaussian-Lorentzian combination profiles using the Python lmfit package, which utilises the algorithms implemented therein. The derived calibration is valid for a wide metallicity range, \\(-4\\)\\,dex\\( \\lesssim \\mathrm{[Fe/H]} \\lesssim +0.15\\), and for ages older than \\(\\sim\\)200 Myr. In addition, we performed a detailed assessment of how factors such as spectral resolution, spectral quality (expressed through the signal-to-noise ratio), and the algorithms used to constrain the line profiles affect the measured line strengths and the resulting metallicities.

Taking advantage of the near-infrared calcium triplet lines, we determine metallicities for a sample of more than 3,500 red giant stars in the field of the Small Magellanic Cloud (SMC). We find a median metallicity of [Fe/H]=-1.05\\(\\pm\\)0.01 dex with a negative metallicity gradient of -0.064\\(\\pm\\)0.007 dex deg\\(^{-1}\\) between 1.2\\deg~to 6.0\\deg consistent with an outside-in evolution scenario. For the first time, we detect hints of a positive metallicity gradient within 1.2\\deg, likely reflecting radial migration or centralised chemical enrichment. Azimuthal metallicity asymmetries are detected, with flatter gradients in the eastern and southern quadrants and steeper ones in the north and west. They are consistent with tidal interaction effects from the Large Magellanic Cloud (LMC). Finally, in spite of a clear distance and velocity bifurcations in the east, they seem to share a common chemical origin, in agreement with other studies.

This work employs molecular dynamic (MD) approaches to characterize the mechanical properties of nanocrystalline materials via a full atomistic simulation using the ab initio derived ReaxFF potential. Herein, we demonstrate methods to efficiently simulate key mechanical properties (ultimate strength, stiffness, etc.) in a timely and computationally inexpensive manner. As an illustrative example, the work implements the described methodology to perform full atomistic simulation on ice as a material platform, which—due to its complex behavior and phase transitions upon pressure, heat exchange, energy transfer etc.—has long been avoided or it has been unsuccessful to ascertain its mechanical properties from a molecular perspective. This study will in detail explain full atomistic MD methods and the particulars required to correctly simulate crystalline material systems. Tools such as the ReaxFF potential and open-source software package LAMMPS will be described alongside their fundamental theories and suggested input methods to simulate further materials, encompassing both periodic and finite crystalline models.

Extra-tidal features around globular clusters (GCs) are tracers of their disruption, stellar stream formation, and their host's gravitational potential. However, these features remain challenging to detect due to their low surface brightness. We conduct a systematic search for such features around 19 GCs in the DECam Local Volume Exploration (DELVE) survey Data Release 2, discovering a new extra-tidal envelope around NGC 5897 and find tentative evidence for an extended envelope surrounding NGC 7492. Through a combination of dynamical modeling and analyzing synthetic stellar populations, we demonstrate these envelopes may have formed through tidal disruption. We use these models to explore the detectability of these features in the upcoming Legacy Survey of Space and Time (LSST), finding that while LSST's deeper photometry will enhance detection significance, additional methods for foreground removal like proper motions or metallicities may be important for robust stream detection. Our results both add to the sample of globular clusters with extra-tidal features and provide insights on interpreting similar features in current and upcoming data.

We present the Dark Energy Camera All Data Everywhere (DECADE) weak lensing dataset: a catalog of 107 million galaxies observed by the Dark Energy Camera (DECam) in the northern Galactic cap. This catalog was assembled from public DECam data including survey and standard observing programs. These data were consistently processed with the Dark Energy Survey Data Management pipeline as part of the DECADE campaign and serve as the basis of the DECam Local Volume Exploration survey (DELVE) Early Data Release 3 (EDR3). We apply the Metacalibration measurement algorithm to generate and calibrate galaxy shapes. After cuts, the resulting cosmology-ready galaxy shape catalog covers a region of \\(5,\\!412 \\,\\, deg^2\\) with an effective number density of \\(4.59\\,\\, arcmin^-2\\). The coadd images used to derive this data have a median limiting magnitude of \\(r = 23.6\\), \\(i = 23.2\\), and \\(z = 22.6\\), estimated at \\( S/N = 10\\) in a 2 arcsecond aperture. We present a suite of detailed studies to characterize the catalog, measure any residual systematic biases, and verify that the catalog is suitable for cosmology analyses. In parallel, we build an image simulation pipeline to characterize the remaining multiplicative shear bias in this catalog, which we measure to be \\(m = (-2.454 0.124) 10^-2\\) for the full sample. Despite the significantly inhomogeneous nature of the data set, due to it being an amalgamation of various observing programs, we find the resulting catalog has sufficient quality to yield competitive cosmological constraints.

We present the photometric redshift characterization and calibration for the Dark Energy Camera All Data Everywhere (DECADE) weak lensing dataset: a catalog of 107 million galaxies observed by the Dark Energy Camera (DECam) in the northern Galactic cap. The redshifts are estimated from a combination of wide-field photometry, deep-field photometry with associated redshift estimates, and a transfer function between the wide field and deep field that is estimated using a source injection catalog. We construct four tomographic bins for the galaxy catalog, and estimate the redshift distribution, \\(n(z)\\), within each one using the Self-organizing Map Photo-Z (SOMPZ) methodology. Our estimates include the contributions from sample variance, zeropoint calibration uncertainties, and redshift biases, as quantified for the deep-field dataset. The total uncertainties on the mean redshifts are \\(_ z 0.01\\). The SOMPZ estimates are then compared to those from the clustering redshift method, obtained by cross-correlating our source galaxies with galaxies in spectroscopic surveys, and are shown to be consistent with each other.