bluuebunny/crossref_metadata_2025_split huggingface dataset:
Generalized Gaussian decomposition for full waveform LiDAR processing
Authors: Gu Zhiyong , Lai Jiancheng , Wang Chunyong , Yan Wei , Ji Yunjing , Li Zhenhua 
Published: January 2022

Abstract
Waveform decomposition techniques are commonly used to extract attributes of targets from light detection and ranging (LiDAR) waveforms. Since the shape of a real LiDAR waveform varies for different systems, the conventional models (e.g. the Gaussian function, lognormal function, and generalized normal function) cannot be universally used. In this paper, we present a generalized Gaussian decomposition (GGD) algorithm, which considers the received waveform as the convolution of an arbitrary system waveform with the target response assumed as a Gaussian mixture model. The proposed method was validated using the experimental waveforms sampled from our self-designed LiDAR system with two different system responses. Metrics, including the mean absolute error (MAE) for range retrieval and the root-mean-squared error (RMSE) for waveform fitting, were used to provide a comprehensive quantitative evaluation of the performance. Three classical models for waveform decomposition—the Gaussian, lognormal, and generalized normal functions—were introduced and studied for the comparison. As for the system waveform with a right-skewed profile, the experimental results showed that the GGD algorithm provided the lowest RMSE for waveform fitting, and the most accurate range estimates with an MAE of

0.030

m

. The Gaussian decomposition (GD), lognormal decomposition (LND), and generalized normal decomposition (GND) algorithms produced much worse results with MAEs of 0.362, 1.091, and

0.417

m

, respectively. As for the system waveform with a negative tail, the GGD algorithm also performed best with an MAE of

0.019

m

, while the GD, LND and GND algorithms provided much larger MAEs of 0.457, 0.489, and

0.354

m

, respectively. Therefore, the proposed method has the potential to extract more accurate model parameters from a variety of LiDAR waveforms regardless of the shape of the system waveform.
MEMS technology and applications in geotechnical monitoring: a review
Authors: Barzegar Milad , Blanks Stan , Sainsbury Bre-Anne , Timms Wendy 
Published: January 2022

Abstract

In-situ monitoring is an important aspect of geotechnical projects to ensure safety and optimise design measures. However, existing conventional monitoring instruments are limited in their accuracy, durability, complex and high cost of installation and requirement for ongoing real time measurement. Advancements in sensing technology in recent years have created a unique prospect for geotechnical monitoring to overcome some of those limitations. For this reason, micro-electro-mechanical system (MEMS) technology has gained popularity for geotechnical monitoring. MEMS devices combine both mechanical and electrical components to convert environment system stimuli to electrical signals. MEMS-based sensors provide advantages to traditional sensors in that they are millimetre to micron sized and sufficiently inexpensive to be ubiquitously distributed within an environment or structure. This ensures that the monitoring of the in-situ system goes beyond discrete point data but provides an accurate assessment of the entire structures response. The capability to operate with wireless technology makes MEMS microsensors even more desirable in geotechnical monitoring where dynamic changes in heterogeneous materials at great depth and over large areas are expected. Many of these locations are remote or hazardous to access directly and are thus a target for MEMS development. This paper provides a review of current applications of existing MEMS technology to the field/s of geotechnical engineering and provides a path forward for the expansion of this research and commercialisation of products.
Use of cubic structure with primitive nanochannels for fabrication of free standing 3D nanowire network of Pt with Pm3m symmetry
Authors: Akbar Samina , Elliott Joanne M , Squires Adam M , Anwar Aneela 
Published: January 2022

Abstract
In this work, we developed a lipid mixture based on phytantriol / polyoxyethylene surfactant (Brij-56) that forms a Im3m symmetry bicontinuous cubic phase based on the Schwartz primitive surface (Q

II

P
), from which we templated highly ordered 3D nanoporous platinum with a novel ‘single primitive’ morphology (Pm3m symmetry). The Q

II

P
template phase is obtained by incorporation of 17.5% w/w Brij-56 (C16EO10) (a type-I surfactant) into phytantriol under excess hydration conditions. Phytantriol alone forms the double diamond Q

II

D
(Pn3m) phase, and in previous studies incorporating Brij-56 at different compositions the cubic phase maintained this morphology, but increased its lattice parameter; mesoporous metals templated from these Q

II

D
lipid templates all exhibited the ‘single diamond’ (Fd3m) morphology. In contrast, the current paper presents the availability of our Q

II

P
cubic phases to template nanoporous materials of single primitive Pm3m morphology via chemical and electrochemical methods. To explore the structure porosity and morphological features of the templated Pt material, x-ray scattering and transmission electron microscopy are used. The resulting 3D nanoporous Pt materials are found to exhibit a regular network of Pt nanowires of ∼4 nm in diameter with a unit cell dimension of 14.8 ± 0.8 nm, reflecting the aqueous network within the Q

II

P
template.
A novel dealloying strategy for fabricating nanoporous Ag via ζ′-AgGa alloy
Authors: Jiang Zhongming , Zhang Jiamin , Wang Kaizhao , Chen Tianyou , Zhao Jiuwei , Wang Kaijun , Hu Jin 
Published: January 2022

AbstractA mild strategy for fabricating nanoporous silver (np-Ag) pieces was reported via preparation of Ag–Ga alloys in relatively low temperature and subsequent electrochemical dealloying in nitric acid (HNO3) aqueous solution. After selectively etching Ga out of the Ag–Ga alloy, a typical three-dimensional (3D) bicontinuous nanoporous structure with a pore size of ∼67.21–159.33 nm was observed. A series of studies have shown that the addition of sodium dodecyl sulfate (SDS) results in minimum pore size. The coarsen exponent (n) is 1.61, and the activation energy was calculated to be 27.04 kJ mol−1. Theζ′-AgGa alloy prepared at low temperature can be used as the precursor for the preparation of fine np-Ags, and this method provides a new strategy for the industrial production of dealloyed np-Ag.
A probabilistic approach for determining Monte Carlo beam source parameters: I. Modeling of a CyberKnife M6 unit
Authors: Duchaine Jasmine , Markel Daniel , Bouchard Hugo 
Published: January 2022

Abstract

Objective. During Monte Carlo modeling of external radiotherapy beams, models must be adjusted to reproduce the experimental measurements of the linear accelerator being considered. The aim of this work is to propose a new method for the determination of the energy and spot size of the electron beam incident on the target of a linear accelerator using a maximum likelihood estimation. Approach. For that purpose, the method introduced by Francescon et al (2008 Med. Phys.
35 504–13) is expanded upon in this work. Simulated tissue-phantom ratios and uncorrected output factors using a set of different detector models are compared to experimental measurements. A probabilistic formalism is developed and a complete uncertainty budget, which includes a detailed simulation of positioning errors, is evaluated. The method is applied to a CyberKnife M6 unit using four detectors (PTW 60012, PTW 60019, Exradin A1SL and IBA CC04), with simulations being performed using the EGSnrc suite. Main results. The likelihood distributions of the electron beam energy and spot size are evaluated, leading to

E

ˆ

=
7.42
±
0.17

MeV

and

F

ˆ

=
2.15
±
0.06

mm

. Using these results and a 95% confidence region, simulations reproduce measurements in 13 out of the 14 considered setups. Significance. The proposed method allows an accurate beam parameter optimization and uncertainty evaluation during the Monte Carlo modeling of a radiotherapy unit.
An abdominal phantom with anthropomorphic organ motion and multimodal imaging contrast for MR-guided radiotherapy
Authors: Weidner Artur , Stengl Christina , Dinkel Fabian , Dorsch Stefan , Murillo Carlos , Seeber Steffen , Gnirs Regula , Runz Armin , Echner Gernot , Karger Christian P , Jäkel Oliver 
Published: January 2022

Abstract

Purpose. Improvements in image-guided radiotherapy (IGRT) enable accurate and precise treatment of moving tumors in the abdomen while simultaneously sparing healthy tissue. However, the lack of validation tools for newly developed MR-guided radiotherapy hybrid devices such as the MR-Linac is an open issue. This study presents a custom developed abdominal phantom with respiratory organ motion and multimodal imaging contrast to perform end-to-end tests for IGRT treatment planning scenarios. Methods. The abdominal phantom contains deformable and anatomically shaped liver and kidney models made of Ni-DTPA and KCl-doped agarose mixtures that can be reproducibly positioned within the phantom. Organ models are wrapped in foil to avoid ion exchange with the surrounding agarose and to provide stable T1 and T2 relaxation times as well as HU numbers. Breathing motion is realized by a diaphragm connected to an actuator that is hydraulically controlled via a programmable logic controller. With this system, artificial and patient-specific breathing patterns can be carried out. In 1.5 T magnetic resonance imaging (MRI), diaphragm, liver and kidney motion was measured and compared to the breathing motion of a healthy male volunteer for different breathing amplitudes including shallow, normal and deep breathing. Results. The constructed abdominal phantom demonstrated organ-equivalent intensity values in CT as well as in MRI. T1-weighted (T1w) and T2-weighted (T2w) relaxation times for 1.5 T and CT numbers were 552.9 ms, 48.2 ms and 48.8 HU (liver) as well as 950.42 ms, 79 ms and 28.2 HU (kidney), respectively. These values were stable for more than six months. Extracted breathing motion from a healthy volunteer revealed a liver to diaphragm motion ratio (LDMR) of 64.4% and a kidney to diaphragm motion ratio (KDMR) of 30.7%. Well-comparable values were obtained for the phantom (LDMR: 65.5%, KDMR: 27.5%). Conclusions. The abdominal phantom demonstrated anthropomorphic T1 and T2 relaxation times as well as HU numbers and physiological motion pattern in MRI and CT. This allows for wide use in the validation of IGRT including MRgRT.
Dictionary-based software for proton dose reconstruction and submilimetric range verification
Authors: Onecha V V , Galve P , Ibáñez P , Freijo C , Arias-Valcayo F , Sanchez-Parcerisa D , España S , Fraile L M , Udías J M 
Published: January 2022

Abstract

Objective. This paper presents a new method for fast reconstruction (compatible with in-beam use) of deposited dose during proton therapy using data acquired from a PET scanner. The most innovative feature of this novel method is the production of noiseless reconstructed dose distributions from which proton range can be derived with high precision. Approach. A new MLEM & simulated annealing (MSA) algorithm, developed especially in this work, reconstructs the deposited dose distribution from a realistic pre-calculated activity-dose dictionary. This dictionary contains the contribution of each beam in the plan to the 3D activity and dose maps, as calculated by a Monte Carlo simulation. The MSA algorithm, using a priori information of the treatment plan, seeks for the linear combination of activities of the precomputed beams that best fits the observed PET data, obtaining at the same time the deposited dose. Main results. the method has been tested using simulated data to determine its performance under 4 different test cases: (1) dependency of range detection accuracy with delivered dose, (2) in-beam versus offline verification, (3) ability to detect anatomical changes and (4) reconstruction of a realistic spread-out Bragg peak. The results show the ability of the method to accurately reconstruct doses from PET data corresponding to 1 Gy irradiations, both in intra-fraction and inter-fraction verification scenarios. For this dose level (1 Gy) the method was able to spot range variations as small as 0.6 mm. Significance. out method is able to reconstruct dose maps with remarkable accuracy from clinically relevant dose levels down to 1 Gy. Furthermore, due to the noiseless nature of reconstructed dose maps, an accuracy better than one millimeter was obtained in proton range estimates. These features make of this method a realistic option for range verification in proton therapy.
Detection of solvated electrons below the interface between atmospheric-pressure plasma and water by laser-induced desolvation
Authors: Inagaki Yoshinobu , Sasaki Koichi 
Published: January 2022

Abstract
We have developed a new method to detect solvated (hydrated) electrons at the plasma–water interface. The method is based on laser-induced desolvation followed by the release of free electrons into the plasma. We employed an atmospheric-pressure dc glow discharge, in which the water surface worked as the cathode, in the experiment. When the region just below the water cathode was irradiated with a pulsed laser beam, we observed the pulsed increase in the discharge current. The increase in the discharge current was caused by the release of free electrons, which were produced from hydrated electrons by the laser-induced desolvation. The pulsed increase in the discharge current was sensitive to the laser wavelength. We compared the relationship between the pulsed increase and the laser wavelength with the distribution of the solvation energy of hydrated electrons using Monte Carlo simulation on the transport of free electrons in water. As a result, it was concluded that hydrated electrons produced under the experimental conditions were located at a distance of 7–15 nm from the plasma–water interface.
Standard measurement method for normal state resistance and critical current of resistively shunted Josephson junctions
Authors: Ohkubo M , Uehara G , Beyer J , Mimura M , Tanaka H , Ehara K , Tanaka S , Noguchi T , Mitchell E E , Foley C P , Fagaly R L 
Published: January 2022

Abstract
An important parameter of Josephson junctions (JJs) is the product of normal state resistance (R
n) and critical current (I
c) for designing superconductor analogue devices or digital circuits. Determination of R
n and I
c from voltage–current (U–I) characteristic curves often faces difficulties; in particular I
c is considerably reduced by intrinsic thermal or extrinsic electrical noises. Here, we propose a standard measurement method of R
n and intrinsic critical current (I
ci) for high-T
c superconductor (HTS) grain boundary JJs operated in liquid nitrogen and low-T
c superconductor (LTS) multilayer superconductor/normal-conductor/superconductor (SNS) JJs in liquid helium. The applicable condition of this method is that both HTS and LTS JJs have U–I curves compatible with resistively-shunted junction (RSJ) model. Both R
n and I
ci values are extracted by combining a geometric mean criterion to select a data set and a least-squares fitting method with the RSJ model, eliminating two distortion effects on U–I curves: noise-rounding and self-heating. The combined method ensures relative standard uncertainty values of 1.9% for R
n and 8% for I
ci or better, when the users follow the standard protocol. It is demonstrated that the combined method is valid for d-wave HTS JJs near 77 K, regardless of peculiarities such as 0–π junction transition in d-wave superconductors at lower temperatures, and s-wave LTS SNS JJs with a wide range of junction parameters. This work is the first step to facilitate standardization for superconductor electronics with JJs.
Thermal-hydraulic models for the cooling of HTS power-transmission cables: status and needs
Authors: Savoldi Laura , Placido Daniele , Viarengo Sofia 
Published: January 2022

Abstract
An overview of the main peculiarities of the models currently available in the literature for the thermal-hydraulic analysis of the cooling of the high critical temperature superconducting power transmission cables, mainly in nominal operating conditions, is performed. Several models address specific issues such as the temperature distribution along or across the cables, and their pressure drop, typically with a simplified approach. The verification and validation of the models has not been systematically addressed so far. From analysis of the available literature, the lack of a general model, capable to address thermal-hydraulic transients for the cooling of the different possible cable designs, with the capability to capture both the behaviour of the cable solid components and different cryogens, is highlighted. The main ingredients that such a general thermal-hydraulic model should not miss are presented, also based on the know-how on, and comparison to, similar tools for low critical temperature cables for nuclear fusion applications.
Optimization study of the main parameters of different types of wind turbine generators
*
Authors: Xu Yuanyuan , An Lian-Tong , Jia Xiao-Ping , Jia Bao-Zhu , Maki Naoki 
Published: January 2022

Abstract
The research and development of large-scale wind turbine generators have become a future trend in green renewable energy field from the dual perspectives of the environment and economics. In this work, an electrical design method is first proposed and applied to different types of wind turbine generators, including the high-temperature superconducting (HTS), the permanent magnet, and the traditional copper generators. The optimal electrical designs of the three types of 10 MW wind turbine generators are then created based on the developed design program. Second, the influences of the rated revolution on the basic performance parameters of the HTS generator are investigated, and the results are compared with those of the other two types of generators. It is found that the generator weight decreases with the increases of the rated revolution and the stator outer diameter, and the optimal rated revolution for a generator with a large stator outer diameter is determined to be 40 min−1. Moreover, the weight of the field parts is found to have the same regulation rule as the generator weight. Finally, the design results of the three types of wind turbine generators are comparatively discussed, and it is found that the HTS wind turbine generator is superior to its two counterparts.
Quantum Brownian motion for magnets
Authors: Anders J , Sait C R J , Horsley S A R 
Published: January 2022

Abstract
Spin precession in magnetic materials is commonly modelled with the classical phenomenological Landau–Lifshitz–Gilbert (LLG) equation. Based on a quantized three-dimensional spin + environment Hamiltonian, we here derive a spin operator equation of motion that describes precession and includes a general form of damping that consistently accounts for memory, coloured noise and quantum statistics. The LLG equation is recovered as its classical, Ohmic approximation. We further introduce resonant Lorentzian system–reservoir couplings that allow a systematic comparison of dynamics between Ohmic and non-Ohmic regimes. Finally, we simulate the full non-Markovian dynamics of a spin in the semi-classical limit. At low temperatures, our numerical results demonstrate a characteristic reduction and flattening of the steady state spin alignment with an external field, caused by the quantum statistics of the environment. The results provide a powerful framework to explore general three-dimensional dissipation in quantum thermodynamics.
Few-photon storage on a second timescale by electromagnetically induced transparency in a doped solid
Authors: Hain Marcel , Stabel Markus , Halfmann Thomas 
Published: January 2022

Abstract
We present the experimental demonstration of light storage towards the single photon level at a long storage time by electromagnetically induced transparency in a rare-earth ion-doped Pr3+:Y2SiO5 crystal. We apply decoherence control by static magnetic fields and appropriately designed radio-frequency composite pulse sequences to prolong the storage time in the memory. A rare-earth ion-doped filter crystal prepared by optical pumping serves to efficiently separate the signal at the single photon level from optical noise. Multipass setups around the memory and the filter crystal improve the storage efficiency and filter selectivity. Already without decoherence control, the setup permits storage of single photons in the microsecond regime at a storage efficiency of 42%. With decoherence control we demonstrate storage of weak coherent pulses containing some 10 photons for up to 10 s at a storage efficiency of several percent. The experimental data clearly demonstrate the applicability of EIT light storage to implement a true quantum memory in Pr3+:Y2SiO5 at long storage times. The scientific findings and technical developments are of relevance also to other protocols and media for quantum information storage.
Mathematical modelling and optimal control of the transmission dynamics of enterovirus
Authors: Mabotsa Malebese , Munganga Justin Manango W , Shitu Hassan Adamu 
Published: January 2022

Abstract
We propose a mathematical model for the transmission dynamics of enterovirus, with novelty of incorporating indirect transmission from the environment, inclusion of control interventions (sanitation and hygiene) and optimal control study. We prove that if the basic reproduction number



0

≤
1

, a suitable Lyapunov function is used to establish the global stability of the disease free equilibrium, in which case the infection will die out over time. Our analysis further establish the global stability of the endemic equilibrium based on the approach of Volterra-Lyapunov matrices if



0

>
1

. Our findings show that when



0

>
1

, the endemic equilibrium is globally asymptotically stable. In this case, the enterovirus will invade the population. It is shown that by reducing direct transmission rate by 80%, the basic reproduction number can be reduced below one and thus controlling the infection. Using optimal control, it is shown that the disease can be controlled within a shorter period of time as compared to minimizing the direct contact rate by 80%. Numerical simulations are provided to illustrate the results.
Study of anisotropic polytropes in f (, T) Theory
Authors: Sharif M , Majid Amal , Shafaqat M 
Published: January 2022

Abstract
This paper examines the general formalism and applications of isotropic as well as anisotropic polytropic stars in curvature-matter coupled gravity. For this purpose, we consider static spherical and Schwarzschild spacetimes in the interior and exterior regions, respectively. We use two polytropic equations of state to obtain physically viable solutions of the field equations. The hydrostatic equilibrium and Lane-Emden equations are developed for both isotropic as well as anisotropic cases. We study the effects of anisotropic pressure on the stellar structure. Moreover, we graphically inspect the physical behavior of isotropic as well as anisotropic polytropes through energy conditions and stability criterion. Finally, we discuss Tolman mass to explore some characteristics of the models. It is concluded that more viable and stable polytropes are found in this theory as compared to general relativity.