bluuebunny/crossref_metadata_2025 huggingface dataset:
Dispersion-corrected r2SCAN based double-hybrid functionals
Authors: Wittmann Lukas , Neugebauer Hagen , Grimme Stefan , Bursch Markus
Published: December 2023

The regularized and restored semi-local meta-generalized gradient approximation (meta-GGA) exchange–correlation functional r2SCAN [Furness et al., J. Phys. Chem. Lett. 11, 8208–8215 (2020)] is used to create adiabatic-connection-derived global double-hybrid functionals employing spin-opposite-scaled MP2. The 0-DH, CIDH, QIDH, and 0–2 type double-hybrid functionals are assessed as a starting point for further modification. Variants with 50% and 69% Hartree–Fock exchange (HFX) are empirically optimized (Pr2SCAN50 and Pr2SCAN69), and the effect of MP2-regularization (κPr2SCAN50) and range-separated HFX (ωPr2SCAN50) is evaluated. All optimized functionals are combined with the state-of-the-art London dispersion corrections D4 and NL. The resulting functionals are assessed comprehensively for their performance on main-group and metal-organic thermochemistry on 90 different benchmark sets containing 25 800 data points. These include the extensive GMTKN55 database, additional sets for main-group chemistry, and multiple sets for transition-metal complexes, including the ROST61, the MOR41, and the MOBH35 sets. As the main target of this study is the development of a broadly applicable, robust functional with low empiricism, special focus is put on variants with moderate amounts of HFX (50%), which are compared to the so far successful PWPB95-D4 (50% HFX, 20% MP2 correlation) functional. The overall best variant, ωPr2SCAN50-D4, performs well on main-group and metal-organic thermochemistry, followed by Pr2SCAN69-D4 that offers a slight edge for metal-organic thermochemistry and by the low HFX global double-hybrid Pr2SCAN50-D4 that performs robustly across all tested sets. All four optimized functionals, Pr2SCAN69-D4, Pr2SCAN50-D4, κPr2SCAN50-D4, and ωPr2SCAN50-D4, outperform the PWPB95-D4 functional.
On the interaction between a detonation wave and an inert gas plug: A numerical investigation
Authors: Si Chenwei , Zhao Min , Zhu Yuejin
Published: December 2023

Employing inert gases to attenuate and obstruct the propagation of detonation waves has proven to be an effective strategy for mitigating potential damage in the realm of industrial safety, which involves complex physical and chemical mechanisms. This study utilizes an in-house solver built on the OpenFOAM platform to examine the interaction between a detonation wave and an inert gas plug of various lengths. The results reveal that as the length of the inert gas plug increases, various detonation states emerge downstream of the gas plug, and an exponential relationship is observed between the detonation re-initiation distance and the gas plug's length. In the process of detonation re-initiation, the non-isentropic process within the viscous boundary layer plays a crucial role in initiating the flames at the upper and lower channel walls. Later, the collision between flames initiates the detonation wave. Additionally, a localized detonation can also be triggered through the interaction between the compression wave and the wall. Notably, the impingements of the detonation wave and the transmitted shock wave induce the mixing and downstream motion of the gas plug. In the presence of the detonation re-initiation, the motion patterns of the left and right interfaces of the gas plug can be categorized into two distinct stages, which are mainly because of the impingement of backpropagation expansion waves and the hindrance of the high pressure generated by the detonation re-initiation, respectively. Also, as the length of the inert gas plug increases, the velocity difference between the two stages gradually decreases.
Strong dual-channel nonreciprocal radiation with guided mode resonances
Authors: Wu Jun , Qing Ye Ming
Published: December 2023

A dual-channel thermal emitter, which is composed of an InAs layer atop an aluminum grating backed with a continuous aluminum film, is proposed and studied. Two resonant absorption and emission peaks are achieved at different wavelengths, leading to the achievement of dual-channel strong nonreciprocal radiations at two different wavelengths for an applied magnetic field of 2 T when the angle of incidence is 17°. The physical origin is revealed through illustrating the electromagnetic field distributions at both resonances and also verified through impedance matching. In addition, the perfect nonreciprocity remains stable within a wide range of structure parameters, lowering the cost of manufacture. Moreover, the nonreciprocal radiations for different incident angles and different magnetic fields are also investigated in detail. The concept and conclusions proposed here will be interesting for the development of novel energy conversion and capture devices.
Dynamics of stress waves in graded density impactors during the internal ballistic process
Authors: Zhou Yiheng , Tan Ye , Zhang Ruizhi , Li Zhiguo , Chen Han , Bai Jingsong , Li Lei , Shen Qiang , Luo Guoqiang
Published: December 2023

Quasi-isentropic loading and unloading, employing graded density impactors (GDIs) as flyers in gas gun-driven plate impact experiments, can provide novel and valuable insights into the equation of state and strength properties of the loaded material. However, the internal ballistic process may lead to spalling or debonding of the GDI due to the intricate interactions between stress waves and interfaces. In this study, the wave propagation in the GDI was analyzed using the multimaterial Lagrangian elastic-plastic model and elastic wave propagation theory. The impact of gradient direction, power-law constant p, and thickness of the first and last layers on the tensile stress was investigated. The outcomes reveal that the mechanism of generating tensile stress varies for two gradient directions. Moreover, adjusting the constant p and the layer thickness may decrease the maximum tensile stress by 74.1% (forward graded) and 95.8% (reverse graded), respectively. The outcomes of this research provide a theoretical and simulation basis for designing and fabricating GDIs to be utilized in quasi-isentropic experiments.
On the identifiability and statistical features of a new distributional approach with reliability applications
Authors: Alnssyan Badr , Ahmad Zubair , Malela-Majika Jean-Claude , Seong Jin-Taek , Shafik Wasswa
Published: December 2023

Probability distributions have prominent applications in different sectors. Among these sectors, probability models are mostly used to analyze datasets in engineering. Among the existing probability distributions, the two-parameter Weibull model plays an important role in providing the best fit for engineering and other related datasets. This paper introduces a new method called a novel updated-W (denoted by “NU-W”) family of distributions that is used to develop a new updated form of the Weibull distribution. The proposed updated extension of the Weibull model is referred to as a novel updated Weibull (denoted as NU-Weibull) distribution. Distributional properties such as identifiability, heavy-tailed characteristic, and rth moment of the NU-W family are derived. The residual life analysis of the NU-Weibull distribution is provided. Finally, two physical applications from civil engineering and reliability sectors are analyzed to demonstrate the application and effectiveness of the NU-Weibull distribution. The data fitting results show that the NU-Weibull distribution is a more suitable and best fit for engineering datasets.
Ultralow dark current and high on–off ratio of perovskite photodetectors enabled by 3D/2D/3D heterostructures unipolar barrier
Authors: Ma Yao , Zhao Xin , Xu Xinglu , Wei Wei , Shen Liang
Published: December 2023

Lead halide perovskite photodetectors exhibit outstanding photoelectric performance in multiple parameters and have become a widely studied hotspot. The perovskite with single crystal structures significantly reduces the density of grain boundaries and defect states, thereby improving the carrier lifetime and mobility. However, the suppression of dark current is one of the most important concerns for the research of perovskite photodetectors. Here, we constructed a pBp unipolar barrier photodetector by inserting two-dimensional perovskite into three-dimensional perovskite through a pressure bonding process. The dark current of the photodetector decreased by more than two orders of magnitude, while the photocurrent remained unchanged. The perovskite unipolar barrier photodetectors exhibit excellent photoelectric performance, with an on–off ratio of 106, a specific detectivity of 4.11 × 1012 Jones, a −3 dB cutoff frequency of 344 kHz, and a linear dynamic range of 160 dB, providing a prospective path for weak light detection.
An electron paramagnetic resonance study of the electron transport in heavily Si-doped high Al content AlxGa1−xN
Authors: Zvanut M. E. , Hanle Jackson P. , Paudel Subash , Page Ryan , Savant Chandrashekhar , Cho Yongjin , Xing H. Grace , Jena Debdeep
Published: December 2023

High Al mole fraction AlGaN is an ultrawide bandgap semiconductor with potential applications in power electronics and deep UV detectors. Although n-type material is achievable with Si-doping, the role of Si is controversial, particularly for AlxGa1−xN with x > 0.8. For this paper, AlGaN films were grown by plasma-assisted molecular beam epitaxy onto bulk AlN substrates and doped with 1018–1020 cm−3 Si. We examine electron transport in heavily Si-doped AlxGa1−xN with x ≥ 0.65 using magnetic resonance, which allows us to probe the neutral donors directly rather than the free carriers and avoids complications due to electrical contacts. Transport was studied through the temperature-dependent linewidth of the electron paramagnetic resonance (EPR) signature for the neutral donor. Analysis shows evidence of hopping conductivity in the most lightly doped samples and impurity band formation in the most heavily doped ones. The EPR results, which are consistent with Hall measurements performed on the same samples, are promising for the development of highly conducting high Al content AlGaN.
Effects of guanidinoacetic acid on the growth performance, meat quality, postmortem energy metabolism and muscle fibre types of finishing pigs
Authors: Li Jingzheng , Li Jiaolong , Zhang Lin , Xing Tong , Jiang Yun , Gao Feng
Published: December 2023

Context Meat quality is increasingly being paid more attention by customers and enterprises. However, the modern pursuit of pork production has led to a decline in pork quality. Muscle fibre type is one of the important factors affecting meat quality that can be used as a key control point. Aims This study set out to assess the effects of dietary guanidinoacetic acid (GAA) on the growth performance, meat quality, postmortem energy metabolism, and muscle fibre types of finishing pigs. Methods In total, 180 healthy Duroc × Landrace × Meishan cross castrated male pigs with the similar weight (average 90 kg) were randomly divided into three treatments, with five replicates (pens) per treatment and 12 pigs per pen, including a GAA-free basal diet and basal diet with 0.05% or 0.10% GAA for 15 days. Key results In longissimus thoracis muscle, the results indicated that GAA supplementation decreased the drip loss and the cooking loss in 0.10% GAA group. Meanwhile, in semitendinosus muscle, 0.10% GAA addition increased pH45 min, and decreased the cooking loss. Additionally, GAA addition increased the content of ATP and AMP in semitendinosus muscle. The mRNA expressions of MyHC-I and MyHC-IIa were increased, whereas MyHC-IIx and MyHC-IIb were decreased. Moreover, in longissimus thoracis muscle, GAA addition promoted the mRNA expressions of CaM and NFATc1; in semitendinosus muscle, dietary GAA up-regulated the CnA and NFATc1 mRNA expressions. Conclusions GAA addition improved the meat quality, enhanced postmortem energy metabolism and promoted the conversion of fast-muscle fibre to slow-muscle fibre via activating the CaN/NFAT signalling. Implications The addition of GAA can improve the meat quality of post-slaughter finishing pigs and provide a theoretical basis for the application of GAA in livestock production.
Structural basis of substrate progression through the bacterial chaperonin cycle
Authors: Gardner Scott , Darrow Michele C. , Lukoyanova Natalya , Thalassinos Konstantinos , Saibil Helen R.
Published: December 2023

The bacterial chaperonin GroEL-GroES promotes protein folding through ATP-regulated cycles of substrate protein binding, encapsulation, and release. Here, we have used cryoEM to determine structures of GroEL, GroEL-ADP·BeF
3
, and GroEL-ADP·AlF
3
-GroES all complexed with the model substrate Rubisco. Our structures provide a series of snapshots that show how the conformation and interactions of non-native Rubisco change as it proceeds through the GroEL-GroES reaction cycle. We observe specific charged and hydrophobic GroEL residues forming strong initial contacts with non-native Rubisco. Binding of ATP or ADP·BeF
3
to GroEL-Rubisco results in the formation of an intermediate GroEL complex displaying striking asymmetry in the ATP/ADP·BeF
3
-bound ring. In this ring, four GroEL subunits bind Rubisco and the other three are in the GroES-accepting conformation, suggesting how GroEL can recruit GroES without releasing bound substrate. Our cryoEM structures of stalled GroEL-ADP·AlF
3
-Rubisco-GroES complexes show Rubisco folding intermediates interacting with GroEL-GroES via different sets of residues.
“A ray of light in the chaos”: Relationships between companion animals and LGBTQ+ emerging adults during the COVID-19 pandemic
Authors: Matijczak Angela , Corley Nicole , Vergara Isabella , Johnson Jake , McDonald Shelby E.
Published: December 2023

There is evidence that pet owners experienced benefits during the COVID-19 pandemic and also struggled with pet-related stressors. Notably, almost all of these studies were conducted with predominantly cisgender and heterosexual samples. This is problematic, as evidence suggests that individuals who belong to marginalized groups, such as LGBTQ+ emerging adults, have been disproportionately affected by stressors associated with the pandemic. This qualitative study explores the unique experiences of LGBTQ+ emerging adults who lived with a pet during the COVID-19 pandemic. Additionally, we sought to identify resources needed to assist LGBTQ+ emerging adult pet owners during the pandemic. The sample included 65 participants aged 18–21 years who had lived with one or more pets within the past year (Mean age = 19.5 years; 36.9% transgender/gender diverse; 40% minoritized racial/ethnic identity). We conducted semi-structured interviews consisting of 18 questions (including five COVID-specific questions). Two authors coded and analyzed the interviews using template analysis. Then, the authors used a thematic analysis approach to organize codes into themes, identify patterns of meaning, and examine relations between themes. Four themes emerged related to the experience of living with a pet during the pandemic. Almost all participants said that their pets provided various types of support to them. Many participants stated that their pets also added stress to their lives during the pandemic. Some participants attributed the changes in their pet’s behavior and/or attitude to pandemic-related quarantines. More than half of the participants discussed changes in their relationship with their pet, with the majority claiming their relationship became stronger. Two themes emerged that related to necessary resources: greater community-based resources (e.g., low-cost veterinary care, pet-friendly outdoor spaces) and more government resources (e.g., better access to information, more material and financial support). Participants offered suggestions for ways to alleviate pet-related stressors, such as developing community-based programs (e.g., pet food pantries, mutual aid programs). There is the opportunity for collaboration between researchers and practitioners in piloting these community programs, as well as implications for policy makers to advocate for policies supportive of LGBTQ+ emerging adult pet owners (e.g., university pet policies, housing policies).
NAK-associated protein 1/NAP1 activates TBK1 to ensure accurate mitosis and cytokinesis
Authors: Paul Swagatika , Sarraf Shireen A. , Nam Ki Hong , Zavar Leila , DeFoor Nicole , Biswas Sahitya Ranjan , Fritsch Lauren E. , Yaron Tomer M. , Johnson Jared L. , Huntsman Emily M. , Cantley Lewis C. , Ordureau Alban , Pickrell Alicia M.
Published: December 2023

Subcellular location and activation of Tank Binding Kinase 1 (TBK1) govern precise progression through mitosis. Either loss of activated TBK1 or its sequestration from the centrosomes causes errors in mitosis and growth defects. Yet, what regulates its recruitment and activation on the centrosomes is unknown. We identified that NAK-associated protein 1 (NAP1) is essential for mitosis, binding to and activating TBK1, which both localize to centrosomes. Loss of NAP1 causes several mitotic and cytokinetic defects due to inactivation of TBK1. Our quantitative phosphoproteomics identified numerous TBK1 substrates that are not only confined to the centrosomes but are also associated with microtubules. Substrate motifs analysis indicates that TBK1 acts upstream of other essential cell cycle kinases like Aurora and PAK kinases. We also identified NAP1 as a TBK1 substrate phosphorylating NAP1 at S318 to promote its degradation by the ubiquitin proteasomal system. These data uncover an important distinct function for the NAP1–TBK1 complex during cell division.
DERnet: a deep neural network for end-to-end reconstruction in magnetic particle imaging
Authors: Peng Zhengyao , Yin Lin , Sun Zewen , Liang Qian , Ma Xiaopeng , An Yu , Tian Jie , Du Yang
Published: December 2023

Objective. Magnetic particle imaging (MPI) shows potential for contributing to biomedical research and clinical practice. However, MPI images are effectively affected by noise in the signal as its reconstruction is an ill-posed inverse problem. Thus, effective reconstruction method is required to reduce the impact of the noise while mapping signals to MPI images. Traditional methods rely on the hand-crafted data-consistency (DC) term and regularization term based on spatial priors to achieve noise-reducing and reconstruction. While these methods alleviate the ill-posedness and reduce noise effects, they may be difficult to fully capture spatial features. Approach. In this study, we propose a deep neural network for end-to-end reconstruction (DERnet) in MPI that emulates the DC term and regularization term using the feature mapping subnetwork and post-processing subnetwork, respectively, but in a data-driven manner. By doing so, DERnet can better capture signal and spatial features without relying on hand-crafted priors and strategies, thereby effectively reducing noise interference and achieving superior reconstruction quality. Main results. Our data-driven method outperforms the state-of-the-art algorithms with an improvement of 0.9–8.8 dB in terms of peak signal-to-noise ratio under various noise levels. The result demonstrates the advantages of our approach in suppressing noise interference. Furthermore, DERnet can be employed for measured data reconstruction with improved fidelity and reduced noise. In conclusion, our proposed method offers performance benefits in reducing noise interference and enhancing reconstruction quality by effectively capturing signal and spatial features. Significance. DERnet is a promising candidate method to improve MPI reconstruction performance and facilitate its more in-depth biomedical application.
Emergence of cosmic space in Tsallis modified gravity from equilibrium and non-equilibrium thermodynamic perspective
Authors: Dheepika M , T Hassan Basari V , Mathew Titus K
Published: December 2023

In the context of Tsallis entropy, we explore the connection between the law of emergence and the thermodynamic laws from a more accurate non-equilibrium perspective. Here, the equilibrium Clausius relation does not conform to the standard energy-momentum conservation. Therefore, an effective gravitational coupling is introduced to rewrite the field equation similar to general relativity, and the corresponding generalized continuity equation is obtained. As a result, thermodynamic laws were modified with the non-equilibrium energy dissipation and entropy production terms, using which we derive the law of emergence. The investigation of the law of emergence and the entropy maximization principle with Tsallis entropy in the non-equilibrium perspective shows that both result in the same constraints as obtained in other gravity theories and the equilibrium context of Tsallis entropy, except for an additional constraint on the Tsallis parameter as a result of extra entropy production. Consequently, the thermodynamic interpretation of the expansion of the universe stays valid even with quantum corrections to the horizon entropy since the correction terms in Tsallis entropy can be treated as the quantum corrections to Bekenstein-Hawking entropy.
Phase diagrams of the diode effect in superconducting heterostructures
Authors: Karabassov T , Bobkova I V , Silkin V M , Lvov B G , Golubov A A , Vasenko A S
Published: December 2023

At present the superconducting diode effect (SDE) attracts a lot of attention due to new possibilities in the superconducting electronics. One of the possible realizations of the SDE is the implementation in superconducting hybrid structures. In this case the SDE is achieved by means of the proximity effect. However, the optimal conditions for the SDE quality factor in hybrid devices remain unclear. In this study we consider the Superconductor/Ferromagnet/Topological insulator (S/F/TI) hybrid device and investigate the diode quality factor at different parameters of the hybrid structure. Consequently, we reveal important parameters that have crucial impact on the magnitude of the SDE quality factor.
The distributed order models to characterize the flow and heat transfer of viscoelastic fluid between coaxial cylinders
Authors: Jiang Jinxia
Published: December 2023

The distributed order fractional derivatives can describe complex dynamic systems. In this paper, considering the periodic pressure gradient and magnetic field, the time distributed order fractional governing equations are established to simulate the two-dimensional flow and heat transfer of viscoelastic fluid between coaxial cylinders. Numerical solutions are obtained by the L1 approximation for the Caputo derivative (L1-scheme) and the finite difference method, and the effectiveness of numerical method is verified by a numerical example. Results demonstrate that the time distributed fractional Maxwell model can promote the flow while the distributed Cattaneo model can weaken heat transfer than the fractional Maxwell and Cattaneo model, and different weight coefficients have different effects on the fluid. The effect of physical parameters, such as the relaxation time of velocity and temperature λ
1, λ
2, the magnetic parameter M, the amplitude P
0 and frequency w of pressure gradient, and the Prandtl number Pr on velocity and temperature are discussed and analysed in detail.
Perfect state transfer by means of discrete-time quantum walk on the complete bipartite graph
Authors: Huang Jiani , Li Dan , Li Panlong , Zhou Yuqian , Yang Yuguang
Published: December 2023

Perfect state transfer has attracted a great deal of attention recently due to its crucial role in quantum communication and scalable quantum computation. In this paper, we propose the perfect state transfer algorithms with a pair of sender-receiver and two pairs of sender-receiver on the complete bipartite graph respectively. The algorithm with a pair of sender-receiver is implemented through discrete-time quantum walk, flexibly setting the coin operators based on the positions of the sender and receiver. The algorithm with two pairs of sender-receiver ensures that the two quantum states are distributed on both sides of the complete bipartite graph during the process, thereby achieving perfect state transfer. In addition, the quantum circuits corresponding to the algorithms are provided. The algorithms can transfer an arbitrary quantum state and can simultaneously transfer two arbitrary quantum states from the senders to the receivers in any case. Moreover, the algorithms are not only applicable to complete bipartite graphs but also to more graph structures with complete bipartite subgraphs, which will provide potential applications for quantum information processing.
Study on low-velocity impact response of kevlar/epoxy-polyurethane sandwich panels
Authors: Taghipoor Hossein , Peysayyar Reza
Published: December 2023

This study aims to investigate the maximum energy absorption of sandwich panels featuring composite facesheets and a polyurethane foam core under low-velocity impact. The research explores various impactor head geometries, fiber orientations, and the number of composite layers on the panel facesheets. Three different impactor heads with flat, hemispherical, and conical shapes were used for experimental impacts. Numerical simulations were performed using Abaqus/Explicit finite element software, with damage initiation in the composite layers determined by the three-dimensional Hashin criterion. The results revealed that the conical-head impactor caused the highest energy absorption, accompanied by the greatest displacement and velocity changes. Among specimens with different fiber orientations, the 60° fiber layers exhibited a 9.41% and 8.45% higher maximum force compared to the 30° and 45° fiber layers, respectively. Furthermore, the study investigated the influence of the number of composite layers in the facesheets. It was found that panels with more layers in the bottom facesheet demonstrated a 4.94% increase in energy absorption compared to panels with more layers in the top facesheet. This research provides valuable insights into optimizing sandwich panel designs for enhanced energy absorption during low-velocity impact scenarios.
The Dbar-dressing method for the (2+1)-dimensional Date–Jimbo–Kashiwara–Miwa equation
Authors: Sun Shifei , Li Biao
Published: December 2023

In this work, the (2+1)-dimensional Date–Jimbo–Kashiwara–Miwa (DJKM) equation is studied by means of the

∂

¯

-dressing method. A new

∂

¯

problem has been constructed by analyzing the characteristic function and the Green’s function of its Lax representation. Based on solving the

∂

¯

equation and choosing the proper spectral transformation, the solution of the DJKM equation is constructed. Furthermore, the more general solution of the DJKM equation can be also obtained by ensuring the evolution of the time spectral data.
Time evolutions of scalar field perturbation in Schwarzschild de-Sitter black hole from Einstein-scalar–Gauss–Bonnet theory
Authors: Xu Cheng , Yang Zhen-Hao , Kuang Xiao-Mei , Yue Rui-Hong
Published: December 2023

The scalar-free black hole could be unstable against the scalar field perturbation when it is coupled to a Gauss–Bonnet (GB) invariant in a special form. It is known that the tachyonic instability in this scenario is triggered by the sufficiently strong GB coupling. In this paper, we focus on the time domain analysis of massive scalar field perturbation around the Schwarzschild de-Sitter black hole in Einstein-scalar–Gauss–Bonnet gravity. By analyzing the scalar field propagation, we find that the scalar field will finally grow when the GB coupling is large enough. This could lead to the instability of the background black hole. Furthermore, we demonstrate how the mass of the scalar field and the GB coupling strength affect the onset of tachyonic instability.
Soliton resolution and asymptotic stability of N-solutions for the defocusing Kundu–Eckhaus equation with nonzero boundary conditions
Authors: Fan Engui , Zhang Yanxi
Published: December 2023

In this paper, we address interesting soliton resolution, asymptotic stability of N-soliton solutions and the Painlevé asymptotics for the Kundu-Eckhaus (KE) equation with nonzero boundary conditions

i

q

t

+

q

xx

−
2
(
∣
q

∣

2

−
1
)
q
+
4

β

2

(
∣
q

∣

4

−
1
)
q

+

4
i
β

∣
q

∣

2

x

q
=
0
,

q
(
x
,
0
)
=

q

0

(
x
)
∼
±
1
,

x
→
±
∞
.

The key to proving these results is to establish the formulation of a Riemann-Hilbert (RH) problem associated with the above Cauchy problem and find its connection with the RH problem of the defocusing NLS equation. With the

∂

¯

-steepest descent method and the results of the defocusing NLS equation, we find complete leading order approximation formulas for the defocusing KE equation on the whole (x,t) half-plane including soliton resolution and asymptotic stability of N-soliton solutions in a solitonic region, Zakharov-Shabat asymptotics in a solitonless region and the Painlevé asymptotics in two transition regions.
Random-search efficiency in a bounded interval with spatially heterogeneous diffusion coefficient
Authors: Menon Jr L , dos Santos M A F , Anteneodo C
Published: December 2023

We consider random walkers searching for a target in a bounded 1D heterogeneous environment, in the interval

[
0
,
L
]

, where diffusion is described by a space-dependent diffusion coefficient D(x). Boundary conditions are absorbing at the position of the target (set at x = 0) and reflecting at the border x = L. We calculate and compare the estimates of efficiency

ε
1

=
⟨
1

/

t
⟩

and

ε
2

=
1

/

⟨
t
⟩

. In the Stratonovich framework of the multiplicative random process, both measures are analytically calculated for arbitrary D(x). For other interpretations of the stochastic integrals (e.g. Itô and anti-Itô), we obtain general results for ɛ
2, while ɛ
1 is obtained for particular forms of D(x). The impact of the diffusivity profile on these measures of efficiency is discussed. Symmetries and peculiar properties arise when the search starts at the border (

x
0

=
L

). In particular, heterogeneity spoils the efficiency of the search within the Stratonovich framework, while for other interpretations the searcher can perform better for certain heterogeneous diffusivity profiles.
Solar insolation and PV module temperature impact on the actual grid connected solar photovoltaic system in German Malaysian Institute
Authors: Mustafa R , Radzi M A Mohd , Hizam H , Soh A Che
Published: December 2023

German Malaysian Institute (GMi) has a great potential for utilising solar photovoltaic (PV) electricity. In this study, the performance of a 3kW grid-connected solar PV (GCSPV) system is monitored using Sunny Portal web in conjunction with Sunny SensorBox. The daily solar energy that strikes a PV array cannot be totally transformed into grid-compatible electricity. As a result of power losses, the production of solar PV systems falls short of expectations. The primary objective of this study is to examine the influence of solar insolation and PV module temperature on the actual output of the GCSPV system compared to the predicted output system by considering elements that affect the conversion of solar power to electrical power in GCSPV systems. The study prediction method based on calculations was carried out. Prediction of output system considered all losses, including efficiency of PV module, solar insolation, temperature of PV module, dirt, manufacturer’s tolerance and module mismatch, the voltage drop in DC cables to inverter, and inverter efficiency. The data indicate that the average power generation is 7.26% lower than predicted by the system. The GCSPV system’s performance efficiency is diminished by the temperature increase and somewhat enhanced by an increase in solar insolation. Temperature has a crucial impact in the energy conversion process of PV module. The effectiveness of the PV module in generating energy and power is dependent on its operating temperature.
Initial Design of Free energy magnetic generator (FEMG)
Authors: Mostaman Nur Afiqah , Sulaiman Erwan , Jenal Mahyuzie , Somroo Irfan Ali
Published: December 2023

Nowadays, it is essential for some areas that there would be implemented such ways for electricity cost reductions in the areas, equipment durability and minimal technical labour demand maintenance. There are many type of generator that can help to generate the electricity such as steam turbines, gasoline turbines, electrical generators, solar or wind turbines, internal combustion engines, and biogas engines. However, there are many drawbacks of using these generators. One of the major drawbacks of these non-renewable generators are the released of hazardous exhausts into the environment such as carbon dioxide, nitrogen oxide, or any other dangerous exhaust. These will produce air pollution, although it imposes environmental costs through manufacture and construction. One of the well-known energy sufficient generator is the permanent magnet generator. The main aim for this project is to design a Free Energy Magnetic Generator (FEMG) using conventional induced voltage generating principle for industrial and residential appliances. The design will be used JMAG Designer Software from designing and observing the generator. It can be concluded that this generator can give a continuous output power supply due to the capability of the generator to produce high output power with low cogging torque which is 2.1Nm. Perhaps, the maximum value of magnetic flux between coil is 2.1066 while the minimum value is 0.0418.
Economic analysis of phase change material integrated photovoltaic thermal systems: A short communication
Authors: Jacob Jeeja , Paul John , Selvaraj Jeyraj , Kadirgama K
Published: December 2023

Solar energy is the most prospective renewable resource that humankind has access to, for acquiring the most usable energy. Photovoltaic thermal systems (PVT) are deemed to be one among the most efficient methods for capturing solar energy because of their distinct ability to produce electrical power by photovoltaic conversion while simultaneously dissipating the heat generated in the process. The necessity of financial investment is a major stumbling block in putting this strategy into action in actual application. This paper delivers updated literature on the economic aspects of PVT-Phase change materials (PCM) systems (installation, operation, and maintenance) that several researchers had carried out. Payback time is taken into account while calculating the profitability of PVT systems. Finally, the performances of several PVT-PCM systems were compared, and the economic analysis confirmed that the PVT system is financially viable. PVT system holds tremendous potential to be incorporated in residential/commercial buildings. The PVT system is a promising technology that still needs refinement in terms of overall efficiency and environmental factors, according to the available literature assessments.
Performance analysis of sandwich switched flux switching permanent magnet motor using modular rotor
Authors: Soomro Irfan Ali , Sulaiman Erwan Bin , Jenal Mahyuzie Bin , Ahmad MD Zarafi Bin
Published: December 2023

Conventional flux-switching permanent magnet brushless machines (PMFSM) gained a lot of attraction due to their high torque densities, simple and robust rotor structure, and the permanent magnets and coils on the stator. The sandwich PMFSM machine has been proposed to improve the torque density of the machine in which two PM pieces are sandwiched in one stator pole to enhance the PMs usage efficiency. 2D finite element analysis (2DFEA) method is employed to compare the performance of sandwich PMFSM with salient rotor topology with that of sandwich PMFSM with modular rotor, in terms of flux linkage, flux distribution, flux strengthening, induced back EMF, cogging torque and average torque. From the results it is shown that the salient sandwich PMFSM and sandwich PMFSM modular rotor produces 9.28Nm and 6.7Nm, respectively.
Evaluation of generation cost-based feed-in tariff rate for wind energy in Myanmar
Authors: Min Y , Selvaraj J , Soe T T
Published: December 2023

Feed-in Tariff (FiT) policy is proven to be an effective mechanism for enabling and accelerating the growth of wind energy industry. The determination of remuneration level in designing FiT system is a critical component that governs the extent of success for adoption of the policy. This study conducts a generation cost-based approach, applying the Net Present Value method, to determine the baseline FiT rate for the case of onshore wind energy in Myanmar. The analysis result indicates that USD 0.1453/kWh is required as a baseline rate to attract the energy producers for investing in Myanmar wind energy sector at the weighted average cost of capital of 11.25%, with debt-to-equity ratio of 70%. The sensitivity analysis is carried out to minimize the uncertainties associated with parameterization. It is found that baseline FiT rate is very sensitive to initial investment cost, and capacity factor whereas it is less sensitive to operation and maintenance cost. It is also found that lower cost of debts and higher debt-to-equity ratios could result in lower FiT values.
Low Harmonics Plug-in Home Charging Electric Vehicle Battery Charger Simulation Model of Zero Crossing
Authors: Arof Saharul , Mawby Philip , Arof Hamzah , Noorsal Emilia
Published: December 2023

Harmonic currents are high in conventional rectifiers. The previous work proposed a new battery charger circuit to reduce harmonics effect and improve total harmonic distortion (THD). The design and development of a home charging electric vehicle battery charger circuit should anticipate potential issues. For this reason, the proposed battery charger, buck chopper, and zero cross circuits must be simulated before real hardware implementation. Simulation and simulation models are needed to describe system behaviour because experimentation might be dangerous, expensive, and time-consuming. This paper describes a simulation model of a zero-crossing circuit and its control algorithm, that provide control signals to a five-level single phase Multi Level Rectifier (MLR)) to draw the MLR for a clean sinusoidal line current with low harmonics. The proposed circuit and the algorithms perform as expected when tested using MATLAB/Simulink and PROTEUS software.
Techno-economic evaluation of CO2 utilization from gas processing facility to blue methanol using green hydrogen
Authors: Martanto Tri , Nizami Muhammad , Purwanto Widodo Wahyu
Published: December 2023

The CO2 waste gas from the gas industry contributes to global warming hence it needs to be reduced or further processed. One of the pathways to utilize CO2 produced from the gas industry is used as a raw material for manufacturing chemicals. This study aims to evaluate techno-economic of CO2 hydrogenation to blue methanol. CO2 sources originated from gas fields located in Central Sulawesi and Central Java and hydrogen from PV electrolysis. The process system was simulated using Aspen HYSYS V.12. The technical analysis was performed using CO2 mass consumption, CO2 conversion, and PV area requirement. The economic analysis was performed using a levelized cost of process. The result shows that CO2 mass consumption for gas fields in Central Sulawesi and Central Java were 1.45 and 1.42 ton-CO2/ton-MeOH, respectively. The CO2 conversion was 94.8% and 96.0% for Central Sulawesi and Central Java, respectively. To produce 1-ton of methanol required PV area of 38,146 m2 in Central Sulawesi and 34,965 m2 in Central Java with methanol production cost in Central Sulawesi and Central Java were 1,960.87 and 1,196.21 $/ton-MeOH, respectively.
WITHDRAWN: Electrical impedance tomography: a review on hardware systems and circuits
Authors: Li Wensheng , Shi Hong , Zhang Luping , Zhang Xinyi , Zhang Fu , Yang Yuxiang
Published: December 2023

Withdrawal

This article has been withdrawn by IOP Publishing due to the work containing multiple figures that were reproduced from other sources without any evidence of permission having been obtained. The authors have not provided proof of permissions, therefore IOP Publishing has made the decision to withdraw the work.
Development of a toroidal soft x-ray imaging system and application for investigating three-dimensional plasma on J-TEXT
Authors: ZHAO 赵 Chuanxu 传旭 , LI 李 Jianchao 建超 , ZHANG 张 Xiaoqing 晓卿 , WANG 王 Nengchao 能超 , DING 丁 Yonghua 永华 , YANG 杨 Zhoujun 州军 , JIANG 江 Zhonghe 中和 , YAN 严 Wei 伟 , LI 李 Yangbo 杨波 , MAO 毛 Feiyue 飞越 , REN 任 Zhengkang 正康 , Team the J-TEXT
Published: December 2023

A toroidal soft x-ray imaging (T-SXRI) system has been developed to investigate three-dimensional (3D) plasma physics on J-TEXT. This T-SXRI system consists of three sets of SXR arrays. Two sets are newly developed and located on the vacuum chamber wall at toroidal positions

of

° and

°, respectively, while one set was established previously at

°. Each set of SXR arrays consists of three arrays viewing the plasma poloidally, and hence can be used separately to obtain SXR images via the tomographic method. The sawtooth precursor oscillations are measured by T-SXRI, and the corresponding images of perturbative SXR signals are successfully reconstructed at these three toroidal positions, hence providing measurement of the 3D structure of precursor oscillations. The observed 3D structure is consistent with the helical structure of the m/n = 1/1 mode. The experimental observation confirms that the T-SXRI system is able to observe 3D structures in the J-TEXT plasma.
On the evolution and formation of discharge morphology in pulsed dielectric barrier discharge
Authors: CHEN 陈 Xingyu 星宇 , LI 李 Mengqi 孟琦 , WANG 王 Weiyi 威逸 , ZHANG 张 Quanzhi 权治 , PENG 彭 Tao 涛 , XIONG 熊 Zilan 紫兰
Published: December 2023

The discharge morphology of pulsed dielectric barrier discharge (PDBD) plays important roles in its applications. Here, we systematically investigated the effects of the voltage amplitude, discharge gap, and O2 content on the PDBD morphology, and revealed the possible underlying mechanism of the U-shaped formation. First, the morphological evolution under different conditions was recorded. A unique U-shaped region appears in the middle edge region when the gap is larger than 2 mm, while the entire discharge region remains columnar under a 2 mm gap in He PDBD. The width of the discharge and the U-shaped region increase with the increase in voltage, and decrease with the increase of the gap and O2 content. To explain this phenomenon, a two-dimensional symmetric model was developed to simulate the spatiotemporal evolution of different species and calculate the electric thrust. The discharge morphology evolution directly corresponds to the excited-state atomic reduction process. The electric thrust on the charged particles mainly determines the reaction region and strongly influences the U-shaped formation. When the gap is less than 2 mm, the electric thrust is homogeneous throughout the entire region, resulting in a columnar shape. However, when the gap is larger than 2 mm or O2 is added, the electric thrust in the edge region becomes greater than that in the middle, leading to the U-shaped formation. Furthermore, in He PDBD, the charged particles generating electric thrust are mainly electrons and helium ions, while in He/O2 PDBD those that generate electric thrust at the outer edge of the electrode surface are mainly various oxygen-containing ions.
Scalable and cost-effective fabrication of high-performance self-powered heterojunction UV-photodetectors using slot-die printing of triple-cation lead perovskite coupled with triboelectric nanogenerators
Authors: Mahmoodpour Sajjad , Shooshtari Leyla , Rafiefard Nassim , Mohammadpour Raheleh , Taghavinia Nima , Vashaee Daryoosh
Published: December 2023

The demand for continuous monitoring of ultraviolet (UV) radiation, which poses significant health risks, has grown significantly with the advent of the internet of things (IoT) for human health. The need for a self-powered system that does not rely on battery charging in environmental conditions has led to the exploration of triboelectric nanogenerators (TENGs) as a promising energy source for sensor systems. In this study, we present a fully printed UV photodetector (UV-PD) that is fabricated through scalable slot-die printing of either single-layer triple-cation mixed halide perovskite (TCMHP) or a heterojunction of TiO2/TCMHP on patterned fluorine-doped tin oxide (FTO). The integrated TENG generates the required energy from the tapping of Kapton to the FTO contact, making the device self-powered. Our self-powered PD exhibits an excellent responsivity and detectivity of 71.4 mA W−1 and 6.92 × 1010 Jones, respectively, under a 395 nm wavelength, significantly outperforming spin-coated TCMHP-based devices. We further optimized the performance of our integrated TENG-powered heterojunction TiO2/TCMHP UV-PD by fabricating sensors with groove spacings of 2, 3, 5, and 8 mm. The optimized device demonstrated an unprecedented responsivity, detectivity, and EQE% of 151.9 mA W−1, 1.29 × 1011 Jones, and 47.8%, respectively, under UV irradiation. Our work represents a significant step towards large-scale industrial flexible self-powered UV detection devices that can protect human health and safety. This study highlights the potential of scalable and cost-effective slot-die printing techniques for the industrial production of high-performance self-powered UV sensors, with significant implications for IoT-based health monitoring and environmental protection applications.
Using random forest for brain tissue identification by Raman spectroscopy
Authors: Zhang Weiyi , Giang Chau Minh , Cai Qingan , Badie Behnam , Sheng Jun , Li Chen
Published: December 2023

The traditional definitive diagnosis of brain tumors is performed by needle biopsy under the guidance of imaging-based exams. This paradigm is based on the experience of radiogolists, and accuracy could be affected by uncertainty in imaging interpretation and needle placement. Raman spectroscopy has the potential to improve needle biopsy by providing fingerprints of different materials and performing in situ tissue identification. In this paper, we present the development of a supervised machine learning algorithm using random forest (RF) to distinguish the Raman spectrum of different types of tissue. An integral process from raw data collection and preprocessing to model training and evaluation is presented. To illustrate the feasibility of this approach, viable animal tissues were used, including ectocinerea (grey matter), alba (white matter) and blood vessels. Raman spectra were acquired using a custom-built Raman spectrometer. The hyperparameters of the RF model were determined by combining a cross-validation-based algorithm and manually adjusting. The experimental results show the ability of our approach to discriminate different types of tissues with high accuracy.