Order Diagrams Research Articles

The Sommerfeld theory with the Uehling potential

The Uehling potential is the one-loop radiative correction to the photon propagator. The correction can be graphically represented by the Feynman diagram of the second order. The physical meaning of this diagram is the process Y-> (e- + e+) -> Y , where Y is denotation for photon, and e-, e+ is the electron-positron pair. It means that photon can exist in the intermediate state with e+, e- being virtual particles. Then, the Coulomb potential with radiative corrections can be inserted in the Sommerfeld quantum equation in order to find the Sommerfeld energy.

VVVX survey dusts off a new intermediate-age star cluster in the Milky Way disk

Context. In the last decade, many new star clusters have been discovered in heavily obscured regions of the Milky Way bulge and disk. Aims. Our primary long-term objective is to seek out additional star clusters in the poorly studied regions of the Milky Way, where detections pose significant challenges. The aim of this pursuit is to finalize the Milky Way’s globular and open cluster system census and to gain a comprehensive understanding of both the formation and evolution of these systems and our Galaxy as a whole. Methods. We report the discovery of a new star cluster, named Garro 03. We investigated this new target using a combination of near-infrared and optical databases. We employed the VISTA Variables in the Via Láctea Survey and Two Micron All Sky Survey data in the near-infrared, and the Gaia Data Release 3 and the DECam Plane Survey datasets in the optical passband. We constructed density maps and vector proper motion diagrams in order to highlight our target. We performed a photometrical analysis in order to derive its main physical parameters. Results. Garro 03 is located at equatorial coordinates RA = 14:01:29.3 and Dec = −65:30:57.0. From our photometric analysis we find that this cluster is not heavily affected by extinction with AKs = 0.25 ± 0.04 mag and AG = 1.54 ± 0.02 mag. It is located at heliocentric distance of 14.1 ± 0.5 kpc, which places Garro 03 at 10.6 kpc from the Galactic centre and Z = −0.89 kpc below the Galactic plane. We also calculated the mean cluster proper motion of (μα*,μδ)=(−4.57 ± 0.29, −1.36 ± 0.27) mas yr−1. We derived an age of 3 Gyr and metallicity [Fe/H] = −0.5 ± 0.2 by the isochrone-fitting method, employing the PARSEC models. The total luminosity was derived in the Ks and V bands, finding MKs = −6.32 ± 1.10 mag and MV = −4.06 mag. Finally, the core and tidal radii were measured constructing the Garro 03 radial density profile and fitting the King model. We obtained rc = 3.07 ± 0.98 pc and rt = 19.36 ± 15.96 pc, respectively. Conclusions. We photometrically confirm the cluster nature for Garro 03, located in the Galactic disk. It is a distant, low-luminosity, metal-rich star cluster of intermediate age. We also searched for possible signatures (streams or bridges) between Garro 03 and Garro 01, but we exclude a companionship with the present analysis. We need spectroscopic data to classify it as an old open cluster or a young globular cluster, and to understand its origin.

EVALUATING THE SOCIAL AND ECONOMIC IMPACT OF ABHA PROJECT UNDER TATA POWER DDL’S CSR INITIATIVES

This research assesses the social and economic effects of the ABHA Project; a CSR intervention by Tata Power DDL targeting vulnerable groups in North and West Delhi. It is expected to include services for the development of deprived communities, which for them mean they will address healthcare, education, and employment services. The method used in the study was ethnographic which included direct observation, surveys, and interviews. The study examines the social, economic and community impact of the project towards empowering the society and enhancing the economic status of the society. According to the data collected, the living standards of the beneficiaries were significantly improved, education, and income sources were enhanced. Nevertheless, some issues concerning distribution of the resources and the sustainability of the programs were raised. Patterns were found with the help of affinity diagrams in order to evaluate the advantages and disadvantages of participants. Based on the findings of this research, the following recommendations are made for Tata Power’s future CSR practices, especially for the expansion of the ABHA project to ensure the delivery of maximum social and economic impact.

Risk-forming areas of mine hoisting equipment and directions for reducing contact loads on shaft reinforcement

The paper considers the influence of diagram of peripheral rotational speed of the rope-driving body (pulley, drum) of a mine hoist on dynamic processes in the system “hoisting vessel - reinforcement” of a vertical mine shaft. It is shown that areas of abrupt speed changes (acceleration or deceleration, override in case of smooth motion disturbances, accidental rubbing, vessel catching on ledges in the guides, etc.) create a peripheral acceleration or deceleration of the pulley or drum rims, which causes longitudinal excitation of the upper ends of the main ropes. These and other factors lead to a sharp increase in the contact loads of shaft guides and braces, and an increased risk of their sudden failure, especially when the safety margins are reduced due to significant wear and tear of metal structures. The ways to adjust and optimize the actual hoisting speed diagram in order to reduce the contact loads on the shaft reinforcement and the associated risks of accidental hazards of mine hoisting equipment (MHE) are determined.

Performance Optimization for 5GWireless Network

Fifth Generation (5th G) wireless network is a challengeable research area. As it is intended to serve growing number of subscribers, and to handle various types of data. Therefore, the need for more number of channels and higher performance is increasing. In this paper, we focus on the adopted modulation scheme by 5th G (256 QAM), where the signals set have been arranged among the constellation diagram in order to reach minimum Bit Error Rate (BER) using Gradient Search Method [1]. The novelty of this study comes from adding permutation loop, which is applied on the resulting signals set of Gradient Algorithm, in order to achieve better performance (lower BER).The results show that acceptable BER under given Signal to Noise Ratio (SNR) could be reached with the relatively large amount of data that is required by this digital modulation scheme.

From micro to bio: using Vee Diagram, concept map and mind map in the framework of REACT strategy in environmental education

Within the scope of the current study, the researchers developed activities for middle school students to raise their awareness on the harm of plastics and microplastics, which are detrimental to nature and living things. In addition, through the activities developed, the study aimed to provide students with knowledge of and experience with bioplastics, which have emerged as an alternative to plastic materials and are environmentally friendly. Twelve eighth grade students participated in the current study. The activities developed by the researchers within the framework of the REACT strategy covered a four-week period. The researchers made sure that the activities designed included each step of the REACT strategy (Relating, Experiencing, Applying, Cooperating, Transferring) and the researchers used different tools (mind map, concept map, Vee diagram). The study suggests that activities designed for classroom use should be integrated with tools such as Vee diagram, concept map and mind map in order to increase students’ knowledge and awareness about global environmental problems as well as support students’ ability to produce solutions to such problems.

On Line Diagrams Plus Modality

In this paper, we produce an extension of Englebretsen’s line diagrams in order to represent modal syllogistic, i.e., we add some diagrammatic objects and rules to his system in order to reason about modal syllogistics in a diagrammatic, linear fashion.

Magnetic Properties of a Mixed Spin-1/2 and Spin-7/2 Hexagonal Core-Shell Nanotube

"The magnetic properties and phase diagrams of a hexagonal nanotube with core-shell structure have been examined within the framework of the mean field theory based on the Bogoliubov inequality as well as the Monte Carlo simulation via the Metropolis algorithm. We have studied in detail the influences of the different ex- change couplings and the crystal field on the phase diagrams of the system. This study allowed us to discover the existence of interesting critical phenomena, in particular the compensation behavior. Moreover, we have investigated the behavior of the magne- tizations corresponding to each of the phase diagrams in order to verify the obtained results."

Landau-Khalatnikov-Fradkin Gauge Transformations for the Propagator and Vertex in QED and QED2

The non-perturbative Landau-Khalatnikov-Fradkin (LKF) transformations describe how Green functions in quantum field theory transform under a change in the photon field’s linear covariant gauge parameter (denoted ξ). The transformations are framed most simply in coordinate space where they are multiplicative. They imply that information on gauge-dependent contributions from higher order diagrams in the perturbative series is contained in lower order contributions, which is useful in multi-loop calculations. We study the LKF transformations for the propagator and the vertex in both scalar and spinor QED, in some particular dimensions. A novelty of our work is to derive momentum-space integral representations of these transformations; our expressions are also applicable to the longitudinal and transverse parts of the vertex. Applying these transformations to the tree-level Green functions, we show that the one-loop terms obtained from the LKF transformation agree with the gauge dependent parts obtained from perturbation theory. Our results will be presented in more comprehensive form elsewhere.

Influence of graphene-based additives on behaviours of electrode materials of Li-ion batteries: A systematic evaluation

Two-dimensional (2D) materials offer interesting properties which cannot be found in bulk materials. Clearly, one of the most important 2D materials is graphene (G) and its derivatives (e.g. graphene oxide, GO, reduced graphene oxide, rGO, etc.). Requirement of the electron conductivity make the G-based materials as potentially promising additives to modify the electrode properties of Li-ion batteries. Consequently, a systematic analytical evaluation is required to understand the effect of these additives in the electrode behaviours and its origins. To this aim, charge-discharge data of the various cathode materials with G-based additives prepared in different situations and labs are taken from literature. The data are applied to three specific diagrams in order to assess the additives' effect on rate-capability, performance, particle activations, and goodness of the active particles. We evaluate the influence of G-based additives, its origins, and their functionalization on each electrode materials as well as entire considered materials. The results show that effectiveness of the additives highly depends on nature of the electrode material, synthesis route, and functionalization of the G-based components during the synthesis; and slightly depends on the preparation parameters and fraction of the additives.

Drawing Order Diagrams Through Two-Dimension Extension

Ordinal real-world data such as concept hierarchies, ontologies, genealogies, or task dependencies in scheduling often has the property to not only contain pairwise comparable, but also incomparable elements. Order diagrams provide an important tool for understanding and thus discovering knowledge in such data. Easily readable drawings of such order diagrams are hard to come by, even for small ordered sets. Many attempts were made to transfer classical graph drawing approaches to order diagrams. Although these methods produce satisfying results for some ordered sets, they unfortunately perform poorly in general. In this work, we present the novel algorithm DimDraw to decompose an ordered set (e.g., a concept hierarchy) in linear orders and to produce a corresponding order diagram. This algorithm is based on a relation between the dimension of an ordered set and the bipartiteness of its transitive incompatibility graph. To evaluate the quality of the algorithm, a user study was conducted where generated drawings were compared with ones from state-of-the-art drawing algorithms.

(γ, χcJ(J = 0,1)) and (γ, ηc) production in electron-positron annihilation at [formula omitted] GeV and 4.6 GeV in the framework of Bethe-Salpeter equation

In present work we study the production of ground and excited charmonium states in e−e+→γχcJ(nP)(J=0,1), and e−e+→γηc(nS), through leading order (LO) diagrams, which proceed through exchange of a virtual photon that couples to γ and ηc/χcJ through the triangular quark loop diagram, in the framework of 4×4 Bethe-Salpeter equation (BSE), at center of mass energies s=10.6 GeV (Belle energy), and 4.6 GeV (BESIII energy). The amplitude simplifies to a general form required by Lorentz-covariance, in terms of its form factors. The cross sections for these processes with leading order diagrams alone at s=10.6 GeV provide a sizable contribution, which might be mainly due to the BSE being a fully relativistic approach that incorporates the relativistic effect of quark spins and can also describe internal motion of constituent quarks within the hadron in a relativistically covariant manner. Our results are compared with recent Belle data at 10.6 GeV, and BESIII data at 4.6 GeV, as well as other models. Plots of cross sections versus the center-of mass energy, s reveal mild fluctuations in their behaviour for all the three processes in the low energy (s=4–6 GeV) region, and are analyzed in terms of the form factors.

Deformation behavior and mechanism of p-type (Bi,Sb)2Te3 alloy during three-point bending test at room temperature

In order to improve the machining process to engineer microstructure and defect types so as to further enhance the thermoelectric properties, it is desirable to understand the deformation behavior and mechanism of polycrystalline Bi2Te3 alloys. This work investigated the deformation behavior and mechanism of (Bi,Sb)2Te3 alloy during three-point bending tests using electron backscatter diffraction (EBSD). Results indicated that both dislocation slip and twinning occurred during the bending tests. The twins with the twin orientation relationship of (0001)M//(0001)T were observed. In addition, the nano-grains extruded the coarse grains in such a way that coarse grains assumed an orientation vulnerable to fracture along the basal planes. Slip trace analysis revealed that 13<112¯0> dislocation slipping on basal planes broke the Van der Waals bonds between the basal planes which eventually led grains to fracture. Additionally, a novel model was introduced that first incorporated the bending moment diagram in order to deduce the deformation process.

Evidence for a large off-centered galactic outflow and its connection to the extraplanar diffuse ionized gas in IC 1553

Aims. We analyze a MUSE optical integral field spectrum of the star-forming edge-on galaxy IC 1553 in order to study its extraplanar diffuse ionized gas (eDIG) and the processes shaping its disk-halo interface. Methods. We extracted the optical emission line properties from the integral field spectrum and generated the commonly used emission line diagnostic diagrams in order to analyze the ionization conditions and the distribution of the eDIG. Furthermore, we performed gravitational potential fitting to investigate the kinematics of a suspected galactic outflow. Results. We find that the eDIG scale height has a maximum value of approximately 1.0 kpc and decreases roughly linearly with the radial distance from the galactic center in projection. The ionization state of the eDIG is not consistent with a pure photoionization scenario and instead requires a significant contribution from shock ionization. This, in addition to the gas kinematics, strongly suggests the presence of a galactic scale outflow, the origin of which lies at least 1.4 kpc away from the galactic center. The inferred shock velocity in the eDIG of approximately 225 km s−1 is comparable to the escape velocity estimated from our potential modelling. The asymmetric distribution of currently star-forming clusters produces a range of different ionization conditions in the eDIG. As a result, the vertical emission line profiles vary quantitatively and qualitatively along the major axis of the galaxy. This analysis illustrates that it is crucial in studies of the eDIG to use observations that take the spatial and kinematical distributions into account, such as those done with integral field units, to form an accurate picture of the relevant physical properties.

Numerical Simulation of PFRC Fracture Subjected to High Temperature by Means of a Trilinear Softening Diagram.

Fibre-reinforced concrete (FRC) has been used for decades in certain applications in the construction industry, such as tunnel linings and precast elements, but has experienced important progress in recent times, boosted by the inclusion of guidelines for its use in some national and international standards. Traditional steel fibres have been studied in depth and their performance is well-known, although in recent years new materials have been proposed as possible alternatives. Polyolefin macro-fibres, for instance, have been proven to enhance the mechanical properties of concrete and the parameters that define their behaviour (fibre length, fibre proportion or casting method, for instance) have been identified. These fibres overcome certain traditional problems related to steel fibres, such as corrosion or their interaction with magnetic fields, which can limit the use of steel in some applications. The behaviour of polyolefin fibre-reinforced concrete (PFRC) has been numerically reproduced with success through an embedded cohesive crack formulation that uses a trilinear softening diagram to describe the fracture behaviour of the material. Furthermore, concrete behaves well under high temperatures or fire events, especially when it is compared with other construction materials, but the behaviour of PFRC must be analysed if the use of these fibres is to be extended. To this end, the degradation of PFRC fracture properties has been recently experimentally analysed under a temperature range between 20 °C and 200 °C. As temperature increases, polyolefin fibres modify their mechanical properties and their shape, which reduce their performance as reinforcements of concrete. In this work, those experimental results, which include results of low (3 kg/m3) and high (10 kg/m3) proportion PFRC specimens, are used as reference to study the fracture behaviour of PFRC exposed to high temperatures from a numerical point of view. The experimental load-deflection diagrams are reproduced by modifying the trilinear diagram used in the cohesive model, which helps to understand how the trilinear diagram parameters are affected by high temperature exposure. Finally, some expressions are proposed to adapt the initial trilinear diagram (obtained with specimens not exposed to high temperature) in order to numerically reproduce the fracture behaviour of PFRC affected by high temperature exposure.

Application of a system dynamics model to evaluate the implementation of payment for environmental services as a reconversion mechanism in high mountain farming

In Colombia, livestock farming has been developed in highlands areas, with influence on these ecosystems and their ecosystem services. Reason why, in 2017, the Colombian issued legal regulations (Decree Law 870), which establishes the payment for environmental services (PES) as a key instrument in the conservation of strategic areas to achieve comprehensive rural development. The objective of this study was to evaluate the response of two type of highlands livestock agroecosystems to the implementation of a mechanism such as the PES, through scenario simulation based on the System Dynamics methodology. It should contribute to the understanding of this activity and to the formulation of policies for land management, use and conservation. Data and information used in this study came from farms located in La Nevera, municipality of Palmira, Department of Valle del Cauca. Gathered information were used to develop qualitative models (i.e. causal loop diagrams) and quantitative models (stock and flow diagrams) in order to built a mechanistic model aimed to improve understanding of the multiple interactions and synergies that constitute the local agro-ecosystems. It includes the livestock and landscape components and their interaction influencing the ecosystem. The developed model evaluated three alternative scenarios of management with eventual economic incentives to farmers: i) business as usual; ii) incentive for areas destined to preservation; iii) areas released for restoration and future conservation. The main results showed that the proposed PES are a viable strategy for obtaining additional income for the land owners and they would also contribute to the maintenance of the typical natural coverage of the territory. However only considering economic balances, the opportunity cost of reducing livestock farming to preserve land is lower than cost of expected preservation. It might impair the choice of modifying the preferences of land use within the farms. The novelty of the study was the use of a system dynamic model to evaluate future sustainable patterns of PES to prevent side effects on the Colombian mountain area from a social and environmental point of view.

The Star Formation Across Cosmic Time (SFACT) Survey. III. Spectroscopy of the Initial Catalog of Emission-line Objects

The Star Formation Across Cosmic Time (SFACT) survey is a new narrowband survey designed to detect emission-line galaxies (ELGs) and quasi-stellar objects (QSOs) over a wide range of redshifts in discrete redshift windows. The survey utilizes the WIYN 3.5 m telescope and the Hydra multifiber positioner to perform efficient follow-up spectroscopy on galaxies identified in the imaging part of the survey. Because the objects in the SFACT survey are selected by their strong emission lines, it is possible to obtain useful spectra for even the faintest of our sources (r ∼ 25). Here, we present the 453 objects that have spectroscopic data from the three SFACT pilot-study fields, 415 of which are confirmed ELGs. The methodology for processing and measuring these data is outlined in this paper, and example spectra are displayed for each of the three primary emission lines used to detect objects in the survey (Hα, [O III]λ5007, and [O II]λ3727). Spectra of additional QSOs and nonprimary-emission-line detections are also shown as examples. The redshift distribution of the pilot-study sample is examined, and the ELGs are placed in different emission-line diagnostic diagrams in order to distinguish the star-forming galaxies from the active galactic nuclei.

Identifying local climate change measures and blockades in a tested DBCA-diagram to stimulate learning between cities

Most of the world's cities are coastal, and most of them face the increasing threats associated with climate change. Coastal cities are also growing the fastest, which makes them a risk for millions of people. This increasing threat occurs when sea level rises, compounded by heavy rainfall and high river levels occurring simultaneously (Sanders 2020a). While measures to address climate change in coastal cities are being taken, or are in preparation and/or planning, along with measures for mitigation and adaptation (Sanders &amp; Oliveira 2020), these measures all too often run into blockages, sometimes physical, but often also due to local special circumstances or a lack of financial resources. These are the results of the H2020 Marie Curie 'SOS Climate Waterfront' 2019-2023 research project, in which researchers exchanged their observations on European coastal cities. To make their insights available to other cities in the EU and beyond, the diagram of the 2020 study has been expanded, in line with the recommendations of this study. Observed blockages have also been added to the diagram concerning heritage protection, lack of finances, or opposition from the commons. Subsequently, the diagram was worked out for each of the six cities of the 'SOS Climate Waterfront' project to investigate whether they can be matched on the basis of their diagrams in order to learn from each other. As the research shows, many of the blockages could have been identified earlier in order to lift them in time, so that well-prepared measures could have been implemented. Only then can a city and its citizens become resilient.

Lannér diagrams and combinatorial properties of compact hyperbolic Coxeter polytopes

In this paper we study×0\times _0-products of Lannér diagrams. We prove that every×0\times _0-product of at least four Lannér diagrams with at least one diagram of order≥3\geq 3is superhyperbolic. As a corollary, we obtain that known classifications exhaust all compact hyperbolic Coxeter polytopes that are combinatorially equivalent to products of simplices.We also consider compact hyperbolic Coxeter polytopes whose every Lannér subdiagram has order22. The second result of this paper slightly improves recent Burcroff’s upper bound on the dimension of such polytopes to1212.

The Radiative Corrections to the Maxwell Equations

The one-loop radiative correction to the photon propagator can be graphically represented by the Feynman diagram of the second order. The physical meaning of this diagram is the process Y-&gt; (e- + e+) -&gt; Y , where Y is denotation for photon, and e-, e+ is the electron-positron pair. It means that photon can exist in the intermediate state with the electron and positron as virtual particles. The photon propagation function based on such process with electron-positron pair e-, e+ is derived. The modified Lagrangian of electromagnetic field is derived supposing the modified Green function of photon. The Schwinger source methods of quantum field theory was applied. Then, the modified Maxwell equations are derived from the new Lagrangian.