Pub Date : 2024-08-03DOI: 10.1140/epjb/s10051-024-00754-9
D. Stock, R. Linke, A. Heft, B. Grünler
Classical molecular dynamics simulations are used to study structural properties of a planar interface between amorphous silica and sodium tetrasilicate glass in a dry environment. The interface region is characterised by the change of the network connectivity. The effect of the interfacial microstructure on the diffusion of sodium is analysed within the framework of topological constraint theory. It is shown that the interface represents an elastic phase boundary where a transition to a stressed-rigid phase occurs. The onset of rigidity in the interface region makes the out-diffusion of sodium from the sodium silicate glass more difficult. The topological controlled diffusion kinetics provides an explanation for the barrier property of amorphous silica despite its open network structure.
{"title":"Structural and topological properties of the interface between amorphous silica and sodium tetrasilicate glass studied by molecular dynamics simulation","authors":"D. Stock, R. Linke, A. Heft, B. Grünler","doi":"10.1140/epjb/s10051-024-00754-9","DOIUrl":"10.1140/epjb/s10051-024-00754-9","url":null,"abstract":"<div><p>Classical molecular dynamics simulations are used to study structural properties of a planar interface between amorphous silica and sodium tetrasilicate glass in a dry environment. The interface region is characterised by the change of the network connectivity. The effect of the interfacial microstructure on the diffusion of sodium is analysed within the framework of topological constraint theory. It is shown that the interface represents an elastic phase boundary where a transition to a stressed-rigid phase occurs. The onset of rigidity in the interface region makes the out-diffusion of sodium from the sodium silicate glass more difficult. The topological controlled diffusion kinetics provides an explanation for the barrier property of amorphous silica despite its open network structure.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141881383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-01DOI: 10.1140/epjb/s10051-024-00752-x
Sathi Patra, Soovoojeet Jana, Sayani Adak, T. K. Kar
Dengue is an arthropod-borne viral disease prevalent in tropical and subtropical regions. Its adverse impact on human health and the global economy cannot be exaggerated. To improve the efficacy of vector control measures, there is a critical need for mechanisms that can forecast dengue cases with greater accuracy and urgency than before. So, we employ some deep learning techniques using the previous ten years of weekly dengue cases in Laos. A hybrid model combining CNN and stacked LSTM (BiLSTM) is applied along with CNN, LSTM, BiLSTM, and ConvLSTM in this work. Comparing all the outputs we have derived, hybrid CNN and 1 stacked BiLSTM outperform other deep learning models with the one-step-ahead prediction. Further, we have concluded that hybrid CNN and 1 stacked BiLSTM can considerably boost dengue prediction and can be applied in other dengue-prone regions.
{"title":"A deep learning architecture using hybrid and stacks to forecast weekly dengue cases in Laos","authors":"Sathi Patra, Soovoojeet Jana, Sayani Adak, T. K. Kar","doi":"10.1140/epjb/s10051-024-00752-x","DOIUrl":"10.1140/epjb/s10051-024-00752-x","url":null,"abstract":"<p>Dengue is an arthropod-borne viral disease prevalent in tropical and subtropical regions. Its adverse impact on human health and the global economy cannot be exaggerated. To improve the efficacy of vector control measures, there is a critical need for mechanisms that can forecast dengue cases with greater accuracy and urgency than before. So, we employ some deep learning techniques using the previous ten years of weekly dengue cases in Laos. A hybrid model combining CNN and stacked LSTM (BiLSTM) is applied along with CNN, LSTM, BiLSTM, and ConvLSTM in this work. Comparing all the outputs we have derived, hybrid CNN and 1 stacked BiLSTM outperform other deep learning models with the one-step-ahead prediction. Further, we have concluded that hybrid CNN and 1 stacked BiLSTM can considerably boost dengue prediction and can be applied in other dengue-prone regions.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141868968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-29DOI: 10.1140/epjb/s10051-024-00755-8
Shun-Yu Wang, Zhi-Gang Shao, Cang-Long Wang, Lei Yang
Detection of SF(_6) decomposition gases is crucial in power equipment maintenance. This paper investigates the adsorption behavior of SO(_2) and H(_2)S on the intrinsic and Fe-modified net-Y surfaces using density functional theory. The adsorption parameters and electronic attributes of diverse configurations have been scrutinized. Calculations indicate that net-Y exhibits limited adsorption capacity for both gases. The doped substrate exhibits a localized magnetic moment around the Fe atom, indicating the possible occurrence of the Kondo effect in the system. The substrate chemisorbs with the target gas through the Fe 3d orbitals. Additionally, after the adsorption of gases, the system undergoes a transition from metallic to semiconductor properties, accompanied by a near-complete disappearance of magnetism. Specifically, in two adsorption configurations, the systems manifest the characteristics of half-semiconductor and half-metal, respectively. Our study provides evidence that the incorporation of Fe-modified net-Y shows potential as a disposable device for detecting and purifying the decomposition products of SF(_6), presenting a prospective application for net-Y in spintronic devices.
Abstract SF(_6) 分解气体的检测在电力设备维护中至关重要。本文利用密度泛函理论研究了 SO(_2) 和 H(_2)S 在本征和 Fe 修饰的净-Y 表面上的吸附行为。对不同构型的吸附参数和电子属性进行了仔细研究。计算表明,Net-Y 对这两种气体的吸附能力有限。掺杂基底在铁原子周围表现出局部磁矩,表明该体系中可能存在近藤效应。基底通过铁 3d 轨道与目标气体发生化学吸附。此外,在吸附气体后,该体系经历了从金属特性到半导体特性的转变,同时磁性几乎完全消失。具体来说,在两种吸附构型中,系统分别表现出半半导体和半金属的特性。我们的研究证明,掺入铁改性的净-Y具有作为一次性器件检测和纯化SF(_6)分解产物的潜力,为净-Y在自旋电子器件中的应用提供了前景。
{"title":"Theoretical investigation of the sensing capabilities of intrinsic and Fe-modified net-Y on SF(_6) decomposition products","authors":"Shun-Yu Wang, Zhi-Gang Shao, Cang-Long Wang, Lei Yang","doi":"10.1140/epjb/s10051-024-00755-8","DOIUrl":"10.1140/epjb/s10051-024-00755-8","url":null,"abstract":"<p>Detection of SF<span>(_6)</span> decomposition gases is crucial in power equipment maintenance. This paper investigates the adsorption behavior of SO<span>(_2)</span> and H<span>(_2)</span>S on the intrinsic and Fe-modified net-Y surfaces using density functional theory. The adsorption parameters and electronic attributes of diverse configurations have been scrutinized. Calculations indicate that net-Y exhibits limited adsorption capacity for both gases. The doped substrate exhibits a localized magnetic moment around the Fe atom, indicating the possible occurrence of the Kondo effect in the system. The substrate chemisorbs with the target gas through the Fe 3d orbitals. Additionally, after the adsorption of gases, the system undergoes a transition from metallic to semiconductor properties, accompanied by a near-complete disappearance of magnetism. Specifically, in two adsorption configurations, the systems manifest the characteristics of half-semiconductor and half-metal, respectively. Our study provides evidence that the incorporation of Fe-modified net-Y shows potential as a disposable device for detecting and purifying the decomposition products of SF<span>(_6)</span>, presenting a prospective application for net-Y in spintronic devices.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141873088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-27DOI: 10.1140/epjb/s10051-024-00753-w
P. M. Centres, F. Nieto
The investigation of site percolation on Sierpinski carpets is carried out through comprehensive numerical simulations. We utilize finite- size scaling theory, staying within the constraints of our computational resources, to determine critical exponents and percolation thresholds. Moreover, we employ an approach developed by Elliot et al. (Phys Rev C 6:3185, 1994; Phys Rev C 55:1319, 1997), which streamlines the process by eliminating the necessity of dealing with large lattices. This method facilitates the extraction of critical quantities that characterize the transition from a single generation within a given structure. By implementing this procedure, we enhance efficiency and accuracy in analyzing the percolation phenomenon on Sierpinski carpets. The obtained values of the percolation thresholds are plotted as a function of the fractal dimensions in order to determine the lower critical dimension of the site percolation problem which is calculated to be (d_c^L=1.52). In addition, the behavior of the critical exponents as a function of the fractal dimension is also shown and discussed.
摘要 通过全面的数值模拟研究了西尔品斯基地毯上的点渗流。我们利用有限尺寸缩放理论,在计算资源的限制下,确定了临界指数和渗流阈值。此外,我们还采用了埃利奥特等人开发的一种方法(Phys Rev C 6:3185, 1994; Phys Rev C 55:1319, 1997),通过消除处理大网格的必要性来简化这一过程。这种方法有助于提取临界量,这些临界量是给定结构中单代过渡的特征。通过实施这一程序,我们提高了分析西尔平斯基地毯上渗滤现象的效率和准确性。得到的渗滤阈值与分形维度的函数关系图,以确定位点渗滤问题的下临界维度,计算结果为 (d_c^L=1.52)。此外,还显示并讨论了临界指数作为分形维度函数的行为。
{"title":"Determination of the non-Euclidean lower critical dimension for the site percolation problem","authors":"P. M. Centres, F. Nieto","doi":"10.1140/epjb/s10051-024-00753-w","DOIUrl":"10.1140/epjb/s10051-024-00753-w","url":null,"abstract":"<p>The investigation of site percolation on Sierpinski carpets is carried out through comprehensive numerical simulations. We utilize finite- size scaling theory, staying within the constraints of our computational resources, to determine critical exponents and percolation thresholds. Moreover, we employ an approach developed by Elliot et al. (Phys Rev C 6:3185, 1994; Phys Rev C 55:1319, 1997), which streamlines the process by eliminating the necessity of dealing with large lattices. This method facilitates the extraction of critical quantities that characterize the transition from a single generation within a given structure. By implementing this procedure, we enhance efficiency and accuracy in analyzing the percolation phenomenon on Sierpinski carpets. The obtained values of the percolation thresholds are plotted as a function of the fractal dimensions in order to determine the lower critical dimension of the site percolation problem which is calculated to be <span>(d_c^L=1.52)</span>. In addition, the behavior of the critical exponents as a function of the fractal dimension is also shown and discussed.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141781516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-26DOI: 10.1140/epjb/s10051-024-00738-9
Anil Kumar, D. Bhargavi, P. G. Siddheshwar
The influence of dissipation with viscosity on magnetohydro-convective instability in a saturated Darcy–Brinkman medium is examined. The bottom boundary is designated as adiabatic, whereas the top boundary is isothermal. Numerical linear stability analysis investigates normal modes that disturb the horizontal base flow at different inclinations. The case study shows that the most unstable disturbances are horizontal rolls, normal modes characterized by a wave vector perpendicular to the main flow direction. The horizontal rolls are the favored instability mode. Barletta et al. also showed that horizontal rolls are more unstable than any other oblique roll mode in the hydromagnetic scenario. This finding provides insights into the behavior of MHD fluid flow and heat transfer in porous media, with implications for applications in geoscience, engineering, and environmental science.
{"title":"Magnetohydro-convective instability in a saturated Darcy–Brinkman medium with viscous dissipation","authors":"Anil Kumar, D. Bhargavi, P. G. Siddheshwar","doi":"10.1140/epjb/s10051-024-00738-9","DOIUrl":"10.1140/epjb/s10051-024-00738-9","url":null,"abstract":"<div><p>The influence of dissipation with viscosity on magnetohydro-convective instability in a saturated Darcy–Brinkman medium is examined. The bottom boundary is designated as adiabatic, whereas the top boundary is isothermal. Numerical linear stability analysis investigates normal modes that disturb the horizontal base flow at different inclinations. The case study shows that the most unstable disturbances are horizontal rolls, normal modes characterized by a wave vector perpendicular to the main flow direction. The horizontal rolls are the favored instability mode. Barletta et al. also showed that horizontal rolls are more unstable than any other oblique roll mode in the hydromagnetic scenario. This finding provides insights into the behavior of MHD fluid flow and heat transfer in porous media, with implications for applications in geoscience, engineering, and environmental science.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><img></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141781518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-25DOI: 10.1140/epjb/s10051-024-00744-x
R. Meyer, Graham W. Gibson, Alexander N. Robillard
{"title":"Publisher Correction: Effects of ballistic transport on the thermal resistance and temperature profile in nanowires","authors":"R. Meyer, Graham W. Gibson, Alexander N. Robillard","doi":"10.1140/epjb/s10051-024-00744-x","DOIUrl":"10.1140/epjb/s10051-024-00744-x","url":null,"abstract":"","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjb/s10051-024-00744-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142413658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-25DOI: 10.1140/epjb/s10051-024-00746-9
Yann Lucas Silva, Ariadne de Andrade Costa
Understanding boundary conditions is crucial for properly modeling interactions and constraints within a system. In particular, periodic boundary conditions play an important role, because they allow systems to be treated as if existing in a continuous, constraint-free space, with significant relevance across diverse scientific fields. Our study explores the effects of periodic boundary conditions on Small-World networks by comparing traditional and flat versions derived from Ring and Line networks, respectively, through comparisons of network metrics and disconnection assessments. Recognizing the critical role of network topology in the behavior of dynamical models, we use an epidemic model to show that the structure of a network can either facilitate or hinder the spread of disease, emphasizing the importance of boundary conditions on these dynamics. The faster spread of disease in Ring networks, with shorter Average Shortest Paths, as well as their resilience on keeping network connectivity under rewiring, illustrate the impact that periodic boundary conditions can have on epidemic scenarios.
{"title":"Periodic boundary condition effects in small-world networks","authors":"Yann Lucas Silva, Ariadne de Andrade Costa","doi":"10.1140/epjb/s10051-024-00746-9","DOIUrl":"10.1140/epjb/s10051-024-00746-9","url":null,"abstract":"<p>Understanding boundary conditions is crucial for properly modeling interactions and constraints within a system. In particular, periodic boundary conditions play an important role, because they allow systems to be treated as if existing in a continuous, constraint-free space, with significant relevance across diverse scientific fields. Our study explores the effects of periodic boundary conditions on Small-World networks by comparing traditional and flat versions derived from Ring and Line networks, respectively, through comparisons of network metrics and disconnection assessments. Recognizing the critical role of network topology in the behavior of dynamical models, we use an epidemic model to show that the structure of a network can either facilitate or hinder the spread of disease, emphasizing the importance of boundary conditions on these dynamics. The faster spread of disease in Ring networks, with shorter Average Shortest Paths, as well as their resilience on keeping network connectivity under rewiring, illustrate the impact that periodic boundary conditions can have on epidemic scenarios.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141781600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-25DOI: 10.1140/epjb/s10051-024-00748-7
M. S. Woldesenbet, N. G. Debelo, M. M. Woldemariam
This study employs density functional theory, utilizing plane wave ultra-soft pseudopotentials (PW-USPPs) within the generalized gradient approximation (GGA) and incorporating the Hubbard potential (GGA + U), to investigate the structural, electronic, and magnetic characteristics of Mn-doped 2D—WSe2 monolayers. The pristine WSe2 monolayer is identified as a nonmagnetic direct band gap semiconductor with a band gap of 1.55 eV. Upon substituting Mn for W in the WSe2 monolayer, the resulting structure exhibits enhanced stability, indicated by a negative formation energy. The Mn-doped monolayer-WSe2 adopts a semi-metallic nature, deviating from the nonmagnetic characteristics of the pristine 2D—WSe2, showcasing impurity bands dispersion near the Fermi level. The total magnetic moment within the nearest neighboring interactions of the Mn impurity atoms increases notably and it is attributed to the electron-correlation effect in the high spin state under the GGA + U approximation. However, this correlation effect proves insignificant on the total magnetic moment for the second nearest neighboring interactions, yielding consistent outcomes in both GGA and GGA + U approximations. The transition of ferromagnetic to antiferromagnetic states occurs within the temperature range of 400 K–450 K for low Mn-atom concentrations (below 12.5%), indicating long-range ferromagnetic ordering crucial for high-temperature 2D-diluted magnetic semiconductors. However, at high concentrations of impurity atoms, the temperature drops below room temperature (220 K in 22.2%) in the doped monolayer WSe2, showing weak magnetic interaction. Lastly, the optical properties of the doped system is studied by applying polarization in perpendicular and parallel directions to the plane of the monolayer.
Graphical abstract
本研究采用密度泛函理论,利用广义梯度近似(GGA)中的平面波超软伪势(PW-USPPs)并结合哈伯德势(GGA + U),研究了掺锰二维 WSe2 单层的结构、电子和磁性特征。原始 WSe2 单层被确定为非磁性直接带隙半导体,带隙为 1.55 eV。在 WSe2 单层中用锰取代 W 后,所产生的结构表现出更高的稳定性,形成能为负值。掺杂锰的单层 WSe2 具有半金属性质,偏离了原始二维 WSe2 的非磁性特征,在费米级附近显示出杂质带的分散。锰杂质原子近邻相互作用内的总磁矩显著增加,这归因于高自旋态下 GGA + U 近似的电子相关效应。然而,这种相关效应在第二近邻相互作用的总磁矩上被证明是微不足道的,在 GGA 和 GGA + U 近似中产生了一致的结果。在锰原子浓度较低(低于 12.5%)的情况下,铁磁态向反铁磁态的转变发生在 400 K-450 K 的温度范围内,这表明长程铁磁有序对高温二维稀释磁性半导体至关重要。然而,当杂质原子浓度较高时,掺杂单层 WSe2 的温度会降至室温以下(22.2% 时为 220 K),显示出弱磁相互作用。最后,通过在垂直和平行于单层平面的方向上施加偏振,研究了掺杂体系的光学特性。
{"title":"The effect of Mn-doping on structural, electronic, ferromagnetic, and optical properties of monolayer-WSe2 using first-principles calculations","authors":"M. S. Woldesenbet, N. G. Debelo, M. M. Woldemariam","doi":"10.1140/epjb/s10051-024-00748-7","DOIUrl":"10.1140/epjb/s10051-024-00748-7","url":null,"abstract":"<div><p>This study employs density functional theory, utilizing plane wave ultra-soft pseudopotentials (PW-USPPs) within the generalized gradient approximation (GGA) and incorporating the Hubbard potential (GGA + U), to investigate the structural, electronic, and magnetic characteristics of Mn-doped 2D—WSe<sub>2</sub> monolayers. The pristine WSe<sub>2</sub> monolayer is identified as a nonmagnetic direct band gap semiconductor with a band gap of 1.55 eV. Upon substituting Mn for W in the WSe<sub>2</sub> monolayer, the resulting structure exhibits enhanced stability, indicated by a negative formation energy. The Mn-doped monolayer-WSe<sub>2</sub> adopts a semi-metallic nature, deviating from the nonmagnetic characteristics of the pristine 2D—WSe<sub>2</sub>, showcasing impurity bands dispersion near the Fermi level. The total magnetic moment within the nearest neighboring interactions of the Mn impurity atoms increases notably and it is attributed to the electron-correlation effect in the high spin state under the GGA + U approximation. However, this correlation effect proves insignificant on the total magnetic moment for the second nearest neighboring interactions, yielding consistent outcomes in both GGA and GGA + U approximations. The transition of ferromagnetic to antiferromagnetic states occurs within the temperature range of 400 K–450 K for low Mn-atom concentrations (below 12.5%), indicating long-range ferromagnetic ordering crucial for high-temperature 2D-diluted magnetic semiconductors. However, at high concentrations of impurity atoms, the temperature drops below room temperature (220 K in 22.2%) in the doped monolayer WSe<sub>2</sub>, showing weak magnetic interaction. Lastly, the optical properties of the doped system is studied by applying polarization in perpendicular and parallel directions to the plane of the monolayer.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141781519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-22DOI: 10.1140/epjb/s10051-024-00747-8
Tatsuaki Wada, Antonio M. Scarfone
We have studied the gradient-flow equations in information geometry from a point-particle perspective. Based on the motion of a null (or light-like) particle in a curved space, we have rederived the Hamiltonians which describe the gradient-flows in information geometry.
{"title":"A Hamiltonian approach to the gradient-flow equations in information geometry","authors":"Tatsuaki Wada, Antonio M. Scarfone","doi":"10.1140/epjb/s10051-024-00747-8","DOIUrl":"10.1140/epjb/s10051-024-00747-8","url":null,"abstract":"<p>We have studied the gradient-flow equations in information geometry from a point-particle perspective. Based on the motion of a null (or light-like) particle in a curved space, we have rederived the Hamiltonians which describe the gradient-flows in information geometry.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141781520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-15DOI: 10.1140/epjb/s10051-024-00739-8
Tiago de Sousa Araújo Cassiano, Fábio Luís de Oliveira Paula, Leonardo Luiz e Castro
The appropriate amount of regulation to reconcile social stability and economic prosperity is a subject of intense study and debate. In practice, the degree of regulatory enforcement is at least as important as the regulation itself. In this work, we present a simulation model of society as a network of interacting agents subject to regulation of their economic activities, with varying degrees of enforcement. Each agent’s compliance with regulation is modeled as a string of bits, which also governs the probability of connection with other agents. Each agent has an initial share of the total wealth that changes over the course of transactions. At each simulation step, the poorest agent takes action to achieve a wealth change at the expense of its first neighbors in the network. Non-conformity to regulation is punished with a probability parameter representing the strength of regulatory enforcement. Our results suggest that regulation has the benefit of reducing wealth inequality but also the disadvantage of increasing job instability, which could lead to lower wealth production in the real world. Our analysis indicates a possible method for choosing an optimal level of regulatory enforcement.
{"title":"Does a severe regulatory policy on trade benefit the economy?","authors":"Tiago de Sousa Araújo Cassiano, Fábio Luís de Oliveira Paula, Leonardo Luiz e Castro","doi":"10.1140/epjb/s10051-024-00739-8","DOIUrl":"10.1140/epjb/s10051-024-00739-8","url":null,"abstract":"<p>The appropriate amount of regulation to reconcile social stability and economic prosperity is a subject of intense study and debate. In practice, the degree of regulatory enforcement is at least as important as the regulation itself. In this work, we present a simulation model of society as a network of interacting agents subject to regulation of their economic activities, with varying degrees of enforcement. Each agent’s compliance with regulation is modeled as a string of bits, which also governs the probability of connection with other agents. Each agent has an initial share of the total wealth that changes over the course of transactions. At each simulation step, the poorest agent takes action to achieve a wealth change at the expense of its first neighbors in the network. Non-conformity to regulation is punished with a probability parameter representing the strength of regulatory enforcement. Our results suggest that regulation has the benefit of reducing wealth inequality but also the disadvantage of increasing job instability, which could lead to lower wealth production in the real world. Our analysis indicates a possible method for choosing an optimal level of regulatory enforcement.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141715541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}