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1. LS-VCE Applied to Stochastic Modeling of GNSS Observation Noise and Process Noise

Author:
Pengyu Hou; Jiuping Zha; Teng Liu; Baocheng Zhang
Source:
Remote Sensing 2022 v.14 no.2 pp. -
ISSN:
2072-4292
Subject:
least squares,   etc   ; stochastic processes; variance;     Show all 3 Subjects
Abstract:
... Stochastic models play a crucial role in global navigation satellite systems (GNSS) data processing. Many studies contribute to the stochastic modeling of GNSS observation noise, whereas few studies focus on the stochastic modeling of process noise. This paper proposes a method that is able to jointly estimate the variances of observation noise and process noise. The method is flexible since it is ...
DOI:
10.3390/rs14020258

2. Cross-validation for selecting the penalty factor in least squares model averaging

Author:
Fang Fang; Qiwei Yang; Wenling Tian
Source:
Economics letters 2022 v.217 pp. 110683
ISSN:
0165-1765
Subject:
least squares,   etc   ; economics; models; selection criteria;     Show all 4 Subjects
Abstract:
... Asymptotic properties of least squares model averaging have been discussed in the literature under two different scenarios: (i) all candidate models are under-fitted; and (ii) the candidate models include the true model and may also include over-fitted ones. The penalty factor ϕn in the weight selection criterion plays a critical role. Roughly speaking, ϕn=2 is usually preferred in the first scena ...
DOI:
10.1016/j.econlet.2022.110683

3. Ground Maneuvering Target Focusing via High-Order Phase Correction in High-Squint Synthetic Aperture Radar

Author:
Lei Ran; Zheng Liu; Rong Xie
Source:
Remote Sensing 2022 v.14 no.6 pp. -
ISSN:
2072-4292
Subject:
least squares,   etc   ; monitoring; synthetic aperture radar;     Show all 3 Subjects
Abstract:
... Moving target imaging in high-squint synthetic aperture radar (SAR) shows great potential for reconnaissance and surveillance tasks. For the desired resolution, high-squint SAR has a long-time coherent processing interval (CPI). In this case, the maneuvering motion of the moving target usually causes high-order phase terms in the echoed data, which cannot be neglected for precise focusing. Many gr ...
DOI:
10.3390/rs14061514

4. Wide-Area Grid-Based Slant Ionospheric Delay Corrections for Precise Point Positioning

Author:
Simon Banville; Elyes Hassen; Micah Walker; Jason Bond
Source:
Remote Sensing 2022 v.14 no.5 pp. -
ISSN:
2072-4292
Subject:
least squares,   etc   ; data collection; geodesy; Canada;     Show all 4 Subjects
Abstract:
... Introducing ionospheric information into a precise point positioning (PPP) solution enables faster ambiguity resolution and significantly improves positioning accuracy. To compute such corrections over wide areas, sparse networks with potentially irregular station distributions are often used. This aspect brings a new level of complexity as ionospheric corrections should be weighted appropriately ...
DOI:
10.3390/rs14051073

5. No Morphological Integration of Dorsal Profiles in the Araucanian Horse (Colombia)

Author:
Arcesio Salamanca-Carreño; Pere M. Parés-Casanova; David Eduardo Rangel-Pachón; Jannet Bentez-Molano; Oscar Mauricio Vélez-Terranova
Source:
Animals 2022 v.12 no.13 pp. -
ISSN:
2076-2615
Subject:
least squares,   etc   ; neck; savannas; withers; Colombia;     Show all 5 Subjects
Abstract:
... The aim of this research was to determine if the division between the cervical, dorsal, and croup profiles (three regions commonly assessed for descriptive profile purposes) has a modular basis as well as a morphological integration. For this, a total of 135 digital photographs were obtained, in a lateral view, of adult horses (14 females and 121 geldings; age range: 2–20 years), of the Araucanian ...
DOI:
10.3390/ani12131731

6. Autogenerated Multilocal PLS Models without Pre-classification for Quality Monitoring of Nonlinear Processes with Unevenly Distributed Data

Author:
Lin Xuan You; Junghui Chen
Source:
Industrial & engineering chemistry process design and development 2022 v.61 no.17 pp. 5898-5913
ISSN:
1520-5045
Subject:
least squares,   etc   ; chemistry; equipment; models; process design;     Show all 5 Subjects
Abstract:
... To achieve the desired product qualities for an operating process, the operational status must be monitored. Operating conditions are changed because of the variability in the quality of raw materials and equipment characteristics. The operating conditions are also changed to produce various product grades and to meet time-to-market demands. This makes the process data collected within a wide regi ...
DOI:
10.1021/acs.iecr.1c04461

7. Restoring trilinearity with the purpose of advanced modeling: towards a more effective analysis of Pericarpium Citri Reticulatae during storage periods

Author:
Yaping Li; Qing Cao; Min He; Xinyue Yang; Pingping Zeng; Weiguo Cao
Source:
Heliyon 2022 v.8 no.3 pp. e09138
ISSN:
2405-8440
Subject:
least squares,   etc   ; diodes; flavonoids; flavor; liquid chromatography;     Show all 5 Subjects
Abstract:
... To accurately quantify Pericarpium Citri Reticulatae samples, trilinear structure was restored in the stacked fingerprints for more robust modeling. Initially, liquid chromatography - diode array detector - mass spectrometry (LC-DAD-MS) and head space-solid phase micro extraction coupled to gas chromatography - mass spectrometry (HS-SPME/GC-MS) were utilized to analyze Pericarpium Citri Reticulata ...
DOI:
10.1016/j.heliyon.2022.e09138

8. SWATH-MS2&1: Development and Validation of a Pseudotargeted Lipidomics Method for the Analysis of Glycerol Esters in Milk

Author:
Xian Sun; Jiachen Shi; Ruizhi Li; Xiaoying Chen; Shuang Zhang; Yong-Jiang Xu; Yuanfa Liu
Source:
Journal of agricultural and food chemistry 2022 v.70 no.10 pp. 3331-3343
ISSN:
1520-5118
Subject:
least squares,   etc   ; food chemistry; glycerol; lipidomics; milk;     Show all 5 Subjects
Abstract:
... Glycerol ester (GE) is a kind of important lipid in milk, which varies greatly depending on many factors. In this study, a novel pseudotargeted lipidomics strategy, named SWATH-MS2&1, was developed for the detection of GEs in milk and the Folch method was selected for the sample preparation. The developed method exhibited a competitive alternative to the acknowledged pseudotargeted strategy, inclu ...
DOI:
10.1021/acs.jafc.1c06446

9. Critical comparison of background correction algorithms used in chromatography

Author:
Leon E. Niezen; Peter J. Schoenmakers; Bob W.J. Pirok
Source:
Analytica chimica acta 2022 v.1201 pp. 339605
ISSN:
0003-2670
Subject:
least squares,   etc   ; automation; chromatography; data collection; hybrids;     Show all 5 Subjects
Abstract:
... The objective of the present work was to make a quantitative and critical comparison of a number of drift and noise-removal algorithms, which were proven useful by other researchers, but which had never been compared on an equal basis. To make a rigorous and fair comparison, a data generation tool is developed in this work, which utilizes a library of experimental backgrounds, as well as peak shap ...
DOI:
10.1016/j.aca.2022.339605

10. Interseismic Fault Coupling and Slip Rate Deficit on the Central and Southern Segments of the Tanlu Fault Zone Based on Anhui CORS Measurements

Author:
Tingye Tao; Hao Chen; Shuiping Li; Xiaochuan Qu; Yongchao Zhu
Source:
Remote Sensing 2022 v.14 no.5 pp. -
ISSN:
2072-4292
Subject:
least squares,   etc   ; Russia; geodesy; geophysics; risk; tectonics; China;     Show all 7 Subjects
Abstract:
... The Tanlu fault zone, extending over 2400 km from South China to Russia, is one of the most conspicuous tectonic elements in eastern Asia. In this study, we processed the Global Positioning System (GPS) measurements of Anhui Continuously Operating Reference System (AHCORS) between January 2013 and June 2018 to derive a high-precision velocity field in the central and southern segments of the Tanlu ...
DOI:
10.3390/rs14051093

11. Bloodstain impact pattern Area of Origin estimation using least-squares angles: A HemoVision validation study

Author:
Philip Joris; Els Jenar; Ruben Moermans; Wim Van de Voorde; Dirk Vandermeulen; Peter Claes
Source:
Forensic science international 2022 v.333 pp. 111211
ISSN:
0379-0738
Subject:
least squares,   etc   ; automation; computer software; forensic sciences; uncertainty;     Show all 5 Subjects
Abstract:
... Bloodstain impact pattern Area of Origin (AO) estimation is an important but time-consuming process in criminal investigations. HemoVision is a software package that automates and accelerates this process. To date, however, no study has been published that evaluates HemoVision’s accuracy. Moreover, HemoVision relies on an automated variant of the tangent method to estimate a pattern’s AO, even tho ...
DOI:
10.1016/j.forsciint.2022.111211

12. An integrated framework of gated recurrent unit based on improved sine cosine algorithm for photovoltaic power forecasting

Author:
Huixin Ma; Chu Zhang; Tian Peng; Muhammad Shahzad Nazir; Yiman Li
Source:
Energy 2022 v.256 pp. 124650
ISSN:
0360-5442
Subject:
least squares,   etc   ; algorithms; energy; models; prediction; solar energy;     Show all 6 Subjects
Abstract:
... Accurate prediction of photovoltaic power is of great significance to the storage and utilization of solar power. In this research, a deep learning model for photovoltaic power prediction based on gated recurrent unit network (GRU), improved sine cosine algorithm (ISCA), and complete ensemble empirical mode decomposition (CEEMD) is proposed. Firstly, CEEMD is used to decompose the original photovo ...
DOI:
10.1016/j.energy.2022.124650

13. Application of PLS SEM in Evaluations of Mathematics Statistics II Course Online Learning

Author:
IZZATI RAHMI; MAHDHIVAN SYAFWAN; HAZMIRA YOZZA; IQBAL HAMONANGAN; FRILIANDA WULANDARI
Source:
Jurnal Natural (Aceh) 2022 v.22 no.1 pp. 7-16
ISSN:
2541-4062
Subject:
least squares,   etc   ; COVID-19 infection; education; mathematics; models;     Show all 5 Subjects
Abstract:
... The impact of the COVID-19 pandemic on the education sector includes the learning system that cannot be conducted directly (offline). With the change in the learning system, it is necessary to evaluate whether the implemented online learning system can run well and provide results as expected. The level of student satisfaction is one of the factors that can be used to evaluate online learning. Thi ...
DOI:
10.24815/jn.v22i1.23065

14. An Efficient and Stable High‐Resolution Seismic Imaging Method: Point‐Spread Function Deconvolution

Author:
Jidong Yang; Jianping Huang; Hejun Zhu; George McMechan; Zhenchun Li
Source:
Journal of geophysical research 2022 v.127 no.7 pp. e2021JB023281
ISSN:
2169-9313
Subject:
least squares,   etc   ; geophysics; lighting; models; normal distribution; research;     Show all 6 Subjects
Abstract:
... By fitting observed data with predicted seismograms, least‐squares migration (LSM) computes a generalized inverse for a subsurface reflectivity model, which can improve image resolution and reduce artifacts caused by incomplete acquisition. However, the large computational cost of LSM required for simulations and migrations limits its wide applications for large‐scale imaging problems. Using point ...
DOI:
10.1029/2021JB023281

15. Joint Angle and Range Estimation in Monostatic FDA-MIMO Radar via Compressed Unitary PARAFAC

Author:
Wenshuai Wang; Xianpeng Wang; Jinmei Shi; Xiang Lan
Source:
Remote Sensing 2022 v.14 no.6 pp. -
ISSN:
2072-4292
Subject:
least squares,   etc   ; methodology; radar; remote sensing; simulation models;     Show all 5 Subjects
Abstract:
... In this paper, we study the joint range and angle estimation problem based in monostatic frequency diverse-array multiple-input multiple-output (FDA-MIMO) radar, and propose a method for range and angle estimation base on compressed unitary parallel factor (PARAFAC). First, the received complex signal matrix is stacked into a third-order complex signal tensor. Then, we can transform the obtained t ...
DOI:
10.3390/rs14061398

16. A (partial) resolution of binding enthalpy discrepancies in ITC studies of Ba2+ crown ether complexation: The importance of calibration

Author:
Joel Tellinghuisen
Source:
Analytical biochemistry 2022 v.642 pp. 114481
ISSN:
0003-2697
Subject:
least squares,   etc   ; biochemistry; calorimetry; enthalpy; heat; temperature; titration; variance;     Show all 8 Subjects
Abstract:
... By conducting binding experiments at a range of temperatures T using isothermal titration calorimetry (ITC), one can obtain two estimates of the binding enthalpy — calorimetric (ΔH°cₐₗ) from the experiments at each T, and van't Hoff (ΔH°ᵥH) from the T dependence of the binding constant K°. From thermodynamics it is clear that these two must be identical, but early efforts to demonstrate this for I ...
DOI:
10.1016/j.ab.2021.114481

17. Analysis of Factors Affecting Adoption of Volunteered Geographic Information in the Context of National Spatial Data Infrastructure

Author:
Munir Ahmad; Malik Sikandar Hayat Khayal; Ali Tahir
Source:
ISPRS international journal of geo-information 2022 v.11 no.2 pp. -
ISSN:
2220-9964
Subject:
least squares,   etc   ; infrastructure; spatial data; structural equation modeling; Pakistan;     Show all 5 Subjects
Abstract:
... Spatial data infrastructures (SDIs) have been implemented for the last four decades in most countries. One of the key objectives of SDIs is to ensure the quick availability and accessibility of spatial data. The success of SDI depends on the underlying spatial datasets. Many developing countries such as Pakistan are facing problems in implementing SDI because of the unavailability of spatial data. ...
DOI:
10.3390/ijgi11020120

18. Estimation of semi-varying coefficient models for longitudinal data with irregular error structure

Author:
Yan-Yong Zhao; Jin-Guan Lin; Jian-Qiang Zhao; Zhang-Xiao Miao
Source:
Computational statistics & data analysis 2022 v.169 pp. 107389
ISSN:
0167-9473
Subject:
least squares,   etc   ; CD4-positive T-lymphocytes; data analysis; models;     Show all 4 Subjects
Abstract:
... Semiparametric models are often considered for modeling longitudinal data for a good balance between flexibility and parsimony. In this paper, we focus on the estimation for a longitudinal semi-varying coefficient model which is of irregular errors. A semiparametric profile least-squares method is developed to estimate parameters in the mean function and error structure simultaneously. Then, a two ...
DOI:
10.1016/j.csda.2021.107389

19. Bowl-Shaped Symmetric and Non-symmetric Bis-functionalized Indacenopicenes

Author:
Johannes Bayer; Thomas Huhn
Source:
Journal of organic chemistry 2022 v.87 no.8 pp. 5257-5278
ISSN:
1520-6904
Subject:
least squares,   etc   ; cross-coupling reactions; halogens; organic chemistry; regioselectivity;     Show all 5 Subjects
Abstract:
... Regioselective arrangement of two groups of orthogonal reactivity in bowl-shaped as-indaceno[3,2,1,8,7,6-pqrstuv]picene (Idpc) was key for the synthesis of hetero-bis-functionalized Idpc derivatives. Halogen and methyl groups were positioned at specific positions in the rim area of Idpc at an early stage during the synthesis by functionalization of suitable precursors. Regioselective functionaliza ...
DOI:
10.1021/acs.joc.2c00040

20. Comparing performance of iterative and non-iterative algorithms on various feature schemes for arrhythmia analysis

Author:
Yatao Zhang; Zhenguo Ma; Jiarui Song; Xiaoming Kong; Ziyu Guo; Bin Jiang
Source:
Methods 2022 v.202 pp. 144-151
ISSN:
1046-2023
Subject:
least squares,   etc   ; arrhythmia; principal component analysis; support vector machines;     Show all 4 Subjects
Abstract:
... To evaluate the performance of the classic machine learning algorithms and the effectiveness of various features, the iterative algorithms (i.e., support vector machine (SVM), and least-squares SVM (LS-SVM)) and non-iterative algorithms (i.e., random forest (RF) and naive bayes (NB)) for six feature schemes were performed to classify the ECG recordings. The ECG recordings were initially filtered w ...
DOI:
10.1016/j.ymeth.2021.04.006