bluuebunny/crossref_metadata_2025_split huggingface dataset:
Update of the BIPM comparison BIPM.RI(II)-K1.Co-57 of activity measurements of the radionuclide 57Co to include the 2023 result of the BEV (Austria)
Authors: Coulon Romain , Michotte Carine , Courte Sammy , Nonis Manuel , Gressier Vincent , Brettner-Messler Robert , Lobner Patrick , Taschwer Isabelle Mercedes 
Published: August 2024

Main text
Since 1976, 20 laboratories have submitted 59 samples of 57Co to the International Reference System (SIR) for activity comparison at the Bureau International des Poids et Mesures (BIPM), with comparison identifier BIPM.RI(II)-K1.Co-57. Recently, the BEV (Austria) participated in the comparison. The degrees of equivalence between each equivalent activity measured in the SIR or linked to the SIR from the CCRI(II)-S6.Co-57 comparison have been calculated and the results are given in the form of a table. A graphical representation is also given.
To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.
The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Distribution of distance-based quantum resources outside a radiating Schwarzschild black hole
Authors: Elghaayda Samira , Zhou Xiang , Mansour Mostafa 
Published: August 2024

Abstract
This study aims to investigate the distribution of distance-based quantum resources for fermionic fields in curved Schwarzschild spacetime (SST), as well as for bosonic fields in both flat Minkowski and curved SSTs. To achieve this, we will examine the quantum resources between an observer falling into a Schwarzschild black hole (SBH) and their stationary partner, who shares a Gisin state. Additionally, we will explore the quantum resources that arise when two uniformly accelerated detectors interact with bosonic fields in the Minkowski vacuum. Furthermore, we will investigate the interactions between these detectors and bosonic fields in the Hartle–Hawking and Boulware vacuums outside the SBH. At an infinite Hawking temperature, the quantum resources for the fermionic fields degrade; the rate of degradation is dependent on the distance between the observer and the event horizon, the fermionic frequency mode, and the Gisin state parameters. In the case of the bosonic fields, our results show that entanglement decreases monotonically, either towards zero or a constant value. Moreover, with increasing Unruh temperature, coherence and discord undergo sudden death followed by a sudden birth, and entanglement cannot be revived for a given initial state. Based on our findings, it appears that the Fermi–Dirac and Bose–Einstein statistics represent the primary differences in quantum resource distribution between the fermionic and bosonic cases. These findings may be essential for enhancing our understanding of the distribution of quantum resources in relativistic frameworks.
Flow of water out of a funnel
Authors: Otto Johann , Mungan Carl E 
Published: August 2024

Abstract
The unsteady Bernoulli equation is used to numerically determine the surface height and velocity distribution of water flowing out of a conical tube as a function of time. The speed is found to interpolate between freefall for a cylindrical pipe of constant radius and Torricelli’s law for a funnel having a small exit hole. In addition, the applied force needed to hold the conical vessel in place is calculated using Newton’s second law including the rocket thrust due to the water flowing out of the funnel. A comparison is made with the analogous expressions for the flow through and holding force on a right cylindrical tank having a hole in its bottom face. The level of presentation is appropriate for an undergraduate calculus-based physics course in mechanics that includes a module on fluid dynamics.
High-frequency performance in nanoscale vacuum channel transistors with gate-cathode height difference
Authors: Chen Yuezhong , Zhai Xin , Lin Congyuan , Liu Ziyang , Zhang Xiaobing , Xu Ji 
Published: August 2024

Abstract
Nanoscale vacuum channel transistors (NVCTs) have garnered considerable interest due to their outstanding high frequency characteristics and high reliability, stemming from a distinct carrier transport mechanism compared to solid-state devices. Electrons traverse the nanoscale vacuum channel through scattering-free ballistic transport. However, existing research has predominantly focused on the structural design and optimization of NVCTs, with relatively few studies delving into their high frequency performance. Hence, alongside structural exploration and optimizing, investigating the high-frequency characteristics of NVCTs assumes particular importance. In this study, a novel NVCTs with a gate-cathode height difference structure was proposed and its electrical characteristics were simulated. Simulation results reveal that the presence of gate-cathode height difference effectively enhance the DC characteristics of NVCTs. Moreover, high frequency simulation demonstrate that the proposed device can operate frequency exceeding 1 THz. Whitin the GHz and even terahertz (THz) range, NVCTs exhibits exceptional high frequency properties, including ultrafast response times and minimal distortion. These findings not only offer insights for future structural design and optimization of NVCTs but also underscore the potential of NVCTs in radio frequency and THz applications.
Mediating coherent acoustic phonon oscillation of a 2D semiconductor/3D dielectric heterostructure by interfacial engineering
Authors: Xu Wenxiong , Hou Feiyang , Zhang He , Xia Chuansheng , Li Zhixuan , Li Yuanyuan , Xu Chunxiang , Cui Qiannan 
Published: August 2024

Abstract
Coherent acoustic phonon (CAP) oscillation of a 2D layered semiconductor/3D dielectric heterostructure generated by femtosecond laser pulse excitation can realize ultrafast photoacoustic conversion by emitting picosecond acoustic (PA) pulse; however, the photoacoustic conversion efficiency suffers from interfacial phonon scattering of simultaneously laser-induced lattice heat. Here, taking advantage of graphene’s high thermal conductivity and large acoustic impedance, we demonstrate that phonon scattering can be markedly mediated in a MoS2/graphene/glass heterostructure via femtosecond laser pump–probe measurements. The equilibrium temperatures of the MoS2 lattice have been cooled down by about 45%. As a benefit, both the lifetime of CAP oscillations and the pump pulse-picosecond acoustic pulse energy conversion efficiency have been enhanced by a factor of about 2. Our results offer insights into CAP and PA pulse manipulations via interfacial engineering that are fundamentally important for ultrafast photoacoustics based on 2D layered semiconductors.
Dynamic data reconciliation for enhancing the prediction performance of long short-term memory network
Authors: Zhu Wangwang , Zhu Jialiang , Yang Qinmin , Liu Yi , Zhang Zhengjiang 
Published: August 2024

Abstract
In modern process industries, long short-term memory (LSTM) network is widely used for data-driven modeling. Constrained by measuring instruments and environments, the measured datasets are generally with Gaussian/non-Gaussian distributed measurement noise. The noisy datasets will impact the modeling accuracy of the LSTM network and decrease the prediction performance of it. Aiming at addressing prediction performance impairment of the LSTM network under noisy datasets with Gaussian/non-Gaussian distribution, this study introduces dynamic data reconciliation (DDR) both into LSTM network training and into LSTM network test. Results show that DDR improves not only the data quality based on noisy datasets and the training outputs via the Bayesian formula in the model training step, but also the prediction performance based on offline measured information and the test outputs. The implementation scheme of DDR for Gaussian and non-Gaussian distributed noise is purposely designed. The effectiveness of DDR on the LSTM model is verified in a numerical example and a case involving a set of shared wind power datasets.
Opportunities and challenges of upright patient positioning in radiotherapy
Authors: Volz Lennart , Korte James , Martire Maria Chiara , Zhang Ye , Hardcastle Nicholas , Durante Marco , Kron Tomas , Graeff Christian 
Published: August 2024

Abstract

Objective. Upright positioning has seen a surge in interest as a means to reduce radiotherapy (RT) cost, improve patient comfort, and, in selected cases, benefit treatment quality. In particle therapy (PT) in particular, eliminating the need for a gantry can present massive cost and facility footprint reduction. This review discusses the opportunities of upright RT in perspective of the open challenges. Approach. The clinical, technical, and workflow challenges that come with the upright posture have been extracted from an extensive literature review, and the current state of the art was collected in a synergistic perspective from photon and particle therapy. Considerations on future developments and opportunities are provided. Main results. Modern image guidance is paramount to upright RT, but it is not clear which modalities are essential to acquire in upright posture. Using upright MRI or upright CT, anatomical differences between upright/recumbent postures have been observed for nearly all body sites. Patient alignment similar to recumbent positioning was achieved in small patient/volunteer cohorts with prototype upright positioning systems. Possible clinical advantages, such as reduced breathing motion in upright position, have been reported, but limited cohort sizes prevent resilient conclusions on the treatment impact. Redesign of RT equipment for upright positioning, such as immobilization accessories for various body regions, is necessary, where several innovations were recently presented. Few clinical studies in upright PT have already reported promising outcomes for head&neck patients. Significance. With more evidence for benefits of upright RT emerging, several centers worldwide, particularly in PT, are installing upright positioning devices or have commenced upright treatment. Still, many challenges and open questions remain to be addressed to embed upright positioning firmly in the modern RT landscape. Guidelines, professionals trained in upright patient positioning, and large-scale clinical studies are required to bring upright RT to fruition.
A direct comparison of multi-energy x-ray and proton CT for imaging and relative stopping power estimation of plastic and ex-vivo phantoms
Authors: Fogazzi Elena , Hu Guyue , Bruzzi Mara , Farace Paolo , Kröncke Thomas , Niepel Katharina , Ricke Jens , Risch Franka , Sabel Bastian , Scaringella Monica , Schwarz Florian , Tommasino Francesco , Landry Guillaume , Civinini Carlo , Parodi Katia 
Published: August 2024

Abstract

Objective. Proton therapy administers a highly conformal dose to the tumour region, necessitating accurate prediction of the patient’s 3D map of proton relative stopping power (RSP) compared to water. This remains challenging due to inaccuracies inherent in single-energy computed tomography (SECT) calibration. Recent advancements in spectral x-ray CT (xCT) and proton CT (pCT) have shown improved RSP estimation compared to traditional SECT methods. This study aims to provide the first comparison of the imaging and RSP estimation performance among dual-energy CT (DECT) and photon-counting CT (PCCT) scanners, and a pCT system prototype. Approach. Two phantoms were scanned with the three systems for their performance characterisation: a plastic phantom, filled with water and containing four plastic inserts and a wood insert, and a heterogeneous biological phantom, containing a formalin-stabilised bovine specimen. RSP maps were generated by converting CT numbers to RSP using a calibration based on low- and high-energy xCT images, while pCT utilised a distance-driven filtered back projection algorithm for RSP reconstruction. Spatial resolution, noise, and RSP accuracy were compared across the resulting images. Main results. All three systems exhibited similar spatial resolution of around 0.54 lp/mm for the plastic phantom. The PCCT images were less noisy than the DECT images at the same dose level. The lowest mean absolute percentage error (MAPE) of RSP,

(
0.28
±
0.07
)
%

, was obtained with the pCT system, compared to MAPE values of

(
0.51
±
0.08
)
%

and

(
0.80
±
0.08
)
%

for the DECT- and PCCT-based methods, respectively. For the biological phantom, the xCT-based methods resulted in higher RSP values in most of the voxels compared to pCT. Significance. The pCT system yielded the most accurate estimation of RSP values for the plastic materials, and was thus used to benchmark the xCT calibration performance on the biological phantom. This study underlined the potential benefits and constraints of utilising such a novel ex-vivo phantom for inter-centre surveys in future.
Modelling radiobiology
Authors: Gardner Lydia L , Thompson Shannon J , O’Connor John D , McMahon Stephen J 
Published: August 2024

Abstract
Radiotherapy has played an essential role in cancer treatment for over a century, and remains one of the best-studied methods of cancer treatment. Because of its close links with the physical sciences, it has been the subject of extensive quantitative mathematical modelling, but a complete understanding of the mechanisms of radiotherapy has remained elusive. In part this is because of the complexity and range of scales involved in radiotherapy—from physical radiation interactions occurring over nanometres to evolution of patient responses over months and years. This review presents the current status and ongoing research in modelling radiotherapy responses across these scales, including basic physical mechanisms of DNA damage, the immediate biological responses this triggers, and genetic- and patient-level determinants of response. Finally, some of the major challenges in this field and potential avenues for future improvements are also discussed.
Thermodynamically-consistent constitutive modeling of moisture- and thermo-responsive shape memory polymers
Authors: Gu Jianping , Wang Changchun , Zhang Xiaopeng , Zeng Hao , Wan Mengqi , Sun Huiyu 
Published: August 2024

Abstract
Taking into account that shape memory polymer (SMP)-based devices are often subject to multiple environmental conditions during application, it is difficult to accurately predict their shape memory effect (SME). Thus, constitutive modeling for SMPs in multi-field environments is of great importance. However, most of the models available are limited to describing the temperature-driven SME and do not refer to multi-field conditions. In this paper, a constitutive model for SMPs in hygrothermal environments is developed under a consistent thermodynamic framework. The derivation is based on an additive decomposition of the Helmholtz free energy density and satisfying the first law and second law of thermodynamics. In this paper, the absorbed moisture is categorized into free and bound phases and it is considered that they have different effects on the material properties. Accordingly, it is the first time to study the variation of configurational entropy with different phases in the polymer–moisture system during the moisture diffusion process. For the first time, the validity of the constitutive model proposed in this paper can be confirmed by systematically comparing the modeling results and experimental data of various types of hygrothermal-induced shape memory cycles.
Origami inspired dual matrix intelligent shape memory polymer composite folds for deployable structures
Authors: Hameed Aamna , Khan Kamran A 
Published: August 2024

Abstract
It remains a challenge to develop an intelligent, programmable multifunctional material system capable of recovering shape, withstanding high loads, and detecting folding extent remotely for self-deployable structures used in aerospace, robotics, and medical devices. In this work, our objective is to develop intelligent shape memory polymer composite (iSMPC) folds embedded with reduced graphene oxide-coated self-sensing fabric. This will enable remote sensing of the fold state based on resistance changes and achieve higher strength and modulus. Firstly, we demonstrate the ability to sense the extent of folding and establish the relationship between piezoresistivity and fold state change by conducting cyclic compression analysis on folds with different gap sizes (6 mm, 9 mm, and 12 mm) at temperatures of 25 °C, 35 °C, and 45 °C. The iSMPC fold with a 6 mm gap exhibited the highest bending stiffness (650.3 N mm−1) and curvature (0.55 mm−1), resulting in a higher change in fractional change in resistance (FCR). Subsequently, the shape memory cycles of the 6 mm iSMPC fold were demonstrated through localized controlled heating. Its shape recovery process exhibited repeatable behavior with a high recovery ratio of 95%. Lastly, a two-fold iSMPC structure was developed, and its performance was analyzed during a complete shape memory cycle. The piezoresistive response during higher-temperature cyclic loading resembled that of the single fold, exhibiting an FCR range between −9% and 5%, thereby demonstrating the repeatability of the iSMPC fold response.
Characterization of high-speed writing and reading operations of the superconducting memory cell
Authors: Wang Yue , Zhong Xianghai , Zeng Junwen , Pan Yinping , Zhang Denghui , Yu Shujie , Wu Ling , Zhang Lu , Peng Wei , Ren Jie , Chen Lei , Wang Zhen 
Published: August 2024

Abstract
Superconducting memory cells that use flux quanta as their storage medium can achieve ultra-fast access times with ultra-low power consumption. However, the data signal generated by a flux quantum memory (FQM) cell is usually too weak and too fast to be measured directly. Here, we present a method to characterize the real-time operation of an FQM cell. The storage loop of the FQM cell, configured with a Nb/NbN
X
/Nb Josephson junction, was proven the capability to store multiple flux quanta. The readout was demonstrated by a superconducting quantum interference device composed of underdamped Nb/Al-AlO
X
/Nb Josephson junctions. The writing and reading operations were achieved by a short pulse ranging from 0.1 ns to 2.5 ns, and a constant bit error rate of ∼2.46% was measured for the fabricated FQM cell. The method presented here can be used to study real-time operation of an FQM cell in a direct manner.
Anti-Wilson mechanism for adjusting bandgap and electronic transport property of a half-Heusler material LiCdP
Authors: Zhao Shuo , Zhu Mingfeng , Jiang Liwei , Zheng Yisong 
Published: August 2024

Abstract
Using first-principles calculations, we have found that LiCdP, an existing half-Heusler material, exhibits an anti-Wilson mechanism for adjusting the bandgap. Specifically, instead of widening according to the conventional Wilson mechanism, the bandgap shows a significant decrease in response to lattice strain, eventually closing at 5.02% tensile strain. This anti-Wilson mechanism is attributed to the weakened repulsion between the 3s and 5s orbitals of the P and Cd atoms, respectively, as observed by the analysis of the neighbouring atomic orbital coupling. In addition, we have found that the ZT value, which measures the thermoelectric efficiency of this material, can reach 1.33 at a temperature of T = 1200 K when lattice strain is induced by thermal expansion. This result suggests that LiCdP is an excellent thermoelectric material in a high operating temperature range. From the point of view of actual applications, such an interesting tunability of the bandgap of LiCdP provides a novel alternative for designing electronic or optoelectronic devices in a controllable way.
Warm white light emitting thermally stable Dy3+ activated antimony fluoroborate glasses for n-UV based white LEDs
Authors: Siwach Vertika , Jayasimhadri M 
Published: August 2024

Abstract
A transparent series of trivalent dysprosium (Dy3+) ions activated calcium antimony fluoroborate glass samples (CAFB) were synthesized by the aid of the melt quenching process. The thermogravimetric, structural, and spectroscopic characterizations were evaluated and investigated in detail. Thermogravimetric analysis was performed to determine the glass transition temperature

T

g

and crystallization temperature (Tc) of the prepared host CAFB glass. Raman Spectroscopy and Fourier transform infrared (FT-IR) analyzed the structural orientation as well as bonding formation in the prepared CAFB host and CAFBDy1.0 glass matrix. Furthermore, the optical absorption spectra exhibit various absorption peaks between the n-UV to NIR region (350 to 2000 nm). Under the different n-UV excitation wavelengths, photoluminescence (PL) spectra reflect three foremost emission centres located around 482, 575, and 663 nm in the Dy3+: CAFB glasses. The observed colour coordinates of the prepared CAFBDy glasses were marked in the standard white area of the CIE chart under different n-UV excitation wavelengths. Moreover, temperature-dependent PL (TDPL) studies demonstrate that these glass samples have significant thermal stability and also a large activation energy. Hence, the above-mentioned results prove the versatility of the CAFBDy glasses to make them potential candidates for usage in luminescent device applications.
M-shaped, W-shaped and dark soliton propagation in optical fiber for nonlocal fourth order dispersive nonlinear Schrödinger equation under distinct conditions
Authors: Prinsa N Neja , Parasuraman E , Antosh B Rishab , Mehmet Baskonus Haci , Muniyappan A 
Published: August 2024

Abstract
The formation of soliton in optical fiber governed by nonlocal nonlinear Schrödinger (NLS) equation with fourth order dispersion is studied. The model of nonlocal NLS equation with fourth order dispersion is solved using the new extended auxiliary method and the solutions are obtained. The solutions are in the form of hyperbolic and trigonometric functions which are based on Jacobi elliptic function m. Shape changing soliton in optical fiber for nonlocal fourth order dispersive NLS equation is discussed by suitably choosing the values of kerr and quintic nonlinearities and by varying fourth order dispersion term. The effect of fourth order dispersion on soliton in fiber for different conditions of kerr and quintic nonlinearity is also discussed. In addition, the phase portraits of the system have been investigated and the stability of wave in optical fiber for nonlocal NLS equation is discussed using fourth order Runge-Kutta algorithm. This paper addresses a significant gap in the current literature by examining the impact of fourth order dispersion on the nonlocal NLS equation in optical fiber.