bluuebunny/crossref_metadata_2025_split huggingface dataset:
Positive zero-field splitting and unexpected slow magnetic relaxation in the magneto-chemical calibrant HgCo(NCS)4
Authors: Boča Roman , Titiš Ján , Rajnák Cyril , Krzystek J. 
Published: February 2021

Magnetochemical standard HgCo(NCS)4 with positive zero-field splitting parameter D displays a slow magnetic relaxation strongly dependent upon the external magnetic field.
Economic operation of integrated energy systems considering combined production of hydrogen and medical oxygen
Authors: Ding Haohui , Hu Qinran , Ge Yi , Wu Qiuwei , Dou Xiaobo , Li Yang 
Published: February 2021

Developing integrated energy systems have been considered a feasible pathway to renewable‐powered energy systems. The power to hydrogen technology is recognised as a promising method to enhance the economics of integrated energy systems and help reduce renewable curtailments. However, oxygen‐enriched gas, which is the by‐product of power to hydrogen processes (electrolysation), has not been fully utilised yet. It can be purified to produce medical oxygen at a low cost and may further increase the economics of integrated energy systems. Particularly, at this very moment, the consideration of the combined production of hydrogen and medical oxygen also has the potential to relieve the shortage of medical oxygen due to the outbreak of the 2019 novel coronavirus (COVID‐19). This study proposes a model for the operation of integrated energy systems that consider the combined production of hydrogen and medical oxygen. This model is formulated as a convex mixed‐integer optimisation problem that balances the electricity, heat and hydrogen demands every hour in a 24‐hour period and balances oxygen demand on a daily basis. A test case of Taizhou City has been studied and results show that the combined production of hydrogen and medical oxygen improves the integrated energy system economics.
Dual‐band‐independent tunable multiple‐input–multiple‐output antenna for 4G/5G new radio access network applications
Authors: Hussain Rifaqat 
Published: February 2021

AbstractSlot‐based dual‐band, low‐profile frequency reconfigurable (FR) multiple‐input–multiple‐output (MIMO) antenna design is presented here. Each element is composed of concentric annular slots that are loaded reactively using varactor diodes. Accurate placement of diodes and optimal biasing circuit configuration result in complete control on each of the tuned bands. The unique feature of the proposed work is the independent as well as concurrent tuning of each band over a wide frequency range from 1.7 to 3.8 GHz. Moreover, the competitive advantage of independent tuning and its narrow‐band (NB) operation may result in better power management for RF front‐end devices. The proposed antenna is fabricated using an RO‐4350 substrate with board dimensions 60 × 120 × 0.76 mm3. The proposed dual‐band compact antenna design is suitable to be utilized in the current fourth generation (4G) wireless standards as well as for upcoming fifth generation (5G) new radio access networks (RANs) with sub 6‐GHz operation.
A single‐layer high‐gain dipole antenna array with a bidirectional radiation pattern based on parallel‐strip line
Authors: Wu Zhe , Yun Yu , Miao Zhuang , Lennerstad Håkan 
Published: February 2021

AbstractA single‐layer dipole antenna array with quasi‐Yagi configuration has been proposed and demonstrated, which provides a dual radiation pattern with the same sense. This antenna is mainly composed of a substrate‐supported parallel strip line (PSL) and several periodic dipole elements. Fed by PSL, dipole elements can be stimulated with a uniform power, forming a linear dipole antenna array. By adjusting the elements separation appropriately, the step phase of array factor can be tuned to achieve the same directivity as the element dipole. When an SubMiniature version A (SMA) coaxial connector is connected at the beginning of PSL, the fundamental mode TEM in the PSL is excited and the radiation electromagnetic wave from the dipole elements is achieved. A taper line between the SMA and PSL can be used to reduce the discontinuity, minimizing the reflection coefficient of the port. According to the theory of classical Yagi antenna, the gain can be further improved by introducing multiple directors, achieving the gain increment of about 3 dBi in the proposed design. Considering 5 GHz frequency band applications (4.85–5.2 GHz), the experimental and simulated results show the proposed antenna array has a working bandwidth from 4.85 to 12 GHz.
Starspot modelling of the TESS light curve of CVSO 30
Authors: Koen C. 
Published: February 2021

Aims. I aim to investigate whether the photometric variability in the candidate host star CVSO 30 can be explained by starspots.
Methods. The Transiting Exoplanet Survey Satellite (TESS) light curve of CVSO 30 is separated into two independent non-sinusoidal periodic components. A starspot modelling technique is applied to each of these components.
Results. Combined, the two model light curves reproduce the TESS observations to a high accuracy, obviating the need to invoke planetary transits to describe part of the variability.
La traduzione del podcast
Authors: Saina Francesco 
Published: February 2021

Abstract
Podcasting is increasingly widespread as a digital medium. However, it has not received sufficient or adequate attention yet, particularly regarding research and translation methodology. This article introduces a translation proposal for Serial, one of the most popular podcasts in the world. The case study aims to raise a debate among scholars and communication experts in order to create common strategies and models for translating podcasts, in the hope that it would pave the way for innovative and valuable communication channels, application in pedagogy, and job opportunities in an unexplored scenario.
A cross-boundary approach to the generative nature of translation
Authors: Tan Zaixi 
Published: February 2021

Abstract
Applying insights from Shi Er’s philosophic-cultural studies-based “boundary theory” to the construal of the nature of
translation, this paper discusses the various aspects of what could be regarded as a generative approach to defining translation, ranging
from the idea that translation is a “cross-boundary” activity of communication to the concept of translational generativity and to analyzing
the fundamental properties of what could qualify or disqualify given texts as translation. It thus provides a new understanding of the
nature of translation enhanced by elements of Chinese philosophy and culture.
Reverse bandgap-bowing in nickel-cadmium sulfide alloys (Ni1−x
Cd
x
S) and its origin
Authors: Paramanik Subham , Chatterjee Soumyo , Pal Amlan J 
Published: February 2021

Abstract
We present evolution of band energies in α-NiS when alloyed with a cationic doping through isovalent cadmium (Cd2+). Optical bandgap of nickel-cadmium sulfide (Ni1−x
Cd
x
S) alloys, as a deviation from the linear relationship or Vegard’s law, have exhibited a reverse bandgap-bowing in the form of downward-concave dependence. Such a phenomenon, which manifests as a negative value of bowing coefficient (b), is uncommon in chalcogenide alloys. In this work, we have deliberated on the origin of reverse bandgap-bowing in nickel-cadmium alloys and identified the band responsible for the bowing phenomenon. While thin-films of the alloys were formed through successive ionic layer adsorption and reaction method, tunnel conductance and thereby density of states of the materials were derived from scanning tunneling spectroscopy. The spectroscopy provided the variation of conduction and valence band-edges (CB and VB, respectively) with respect to the cadmium-content in Ni1−x
Cd
x
S. The CB-edge of the alloys could be seen to remain mostly unaffected with increasing cadmium-content, since the band is composed of only the S 2p orbitals; the VB-energy, on the other hand, which forms due to an effective coupling between the metal d and the anion p orbitals, could be seen to be affected due to a p–d repulsion. Based on our experimental findings, we inferred that an antagonism between volume deformation and structural relaxation had resulted in the reverse bandgap-bowing in Ni1−x
Cd
x
S alloys.
Constructing a capacitive rotating angle sensing system using a hand-made oscillator and testers
Authors: Sakon Takuo , Noissiki Sota , Yamazaki Junya 
Published: February 2021

Abstract
In this study, we develop a capacitive rotating angle sensing system using a hand-made 1 kHz oscillator, field-effect transistor (FET) amplifier, and tester through a physics experiment conducted in Ryukoku University. Physics majors of the university can study the fundamentals of electronics through this system because it uses electronic elements, such as transistors and FETs. We fabricated the circuit of a rotation angle sensor system using a fan-type and coaxial variable capacitor. The capacitance of the variable capacitors varied linearly with the rotation angle. Owing to the CR high-pass filter, constructed by capacitors and a 100 kΩ resistor, the output voltage of the system was linear with capacitors and the rotation angle. Not only can this system be used to teach university-level physics, but its applications could extend to various industries.
Motivations and challenges on the inclusion of environmental topics in Brazilian physics teacher education courses
Authors: Leite Danielle Aparecida Reis , Silva Luciano Fernandes 
Published: February 2021

Abstract
In Brazil, environmental topics in teacher education programmes have largely been addressed and explored by the field of research in Environmental Education and subsidized by legislative and normative instruments. Nevertheless, the difficulties in articulating environmental topics within some areas of knowledge compromise their integration in certain subject-specific courses, as is the case for initial physics teacher education courses. In this light, this article seeks to identify the main challenges and motivations to incorporating environmental topics in physics teacher education courses, with the aim of identifying strategies that may contribute to overcoming these difficulties. Interviews were carried out with 15 physics teacher education courses coordinators at state-funded higher education institutions in the state of São Paulo, Brazil. Drawing upon Content Analysis procedures, analysis was conducted on the interview transcripts as well as pedagogical plan courses. The main findings highlight that the presence of environmental topics in these programmes reflects legislative and normative requirements. In addition, other factors motivated the inclusion of environmental topics in these courses, thus indicating recognition of its importance to initial physics teacher education. This study also shows that the small number of university lecturers and professors involved in environmental education working within these programmes is the main challenge to including environmental topics in initial physics teacher education curriculum.
Secondary school students’ conceptions about the viscous behaviour of liquids
Authors: Faltin Lukas , Feser Markus Sebastian 
Published: February 2021

Abstract
Since the viscous behaviour of liquids is evident in many everyday situations, it is plausible to assume that students have (pre-)conceptions about the physics behind these phenomena. As yet, no reliable studies exist on this topic. Therefore, the present study aims to address this research gap by exploring secondary school students’ conceptions about the viscous behaviour of liquids. For this purpose, we conducted structured interviews with 12 ninth grade students, in which the students were asked to describe and explain various viscosity phenomena of everyday life, presented to them as video clips. Our analysis of the interviews revealed that many of the students have the conception that density is associated with viscous behaviour. In addition, some students explain viscous behaviour with reference to the ingredients of a liquid or by its stickiness or compression. Further, both macroscopic- and sub-microscopic-level explanations for the viscous behaviour of liquids emerged in the interviews.
Multiple electrically tunable parametric resonances in a capacitively coupled electromechanical resonator for broadband energy harvesting
Authors: Surappa Sushruta , Erdogan Tuna , Degertekin F Levent 
Published: February 2021

Abstract
Parametric excitation (PE) has widely been employed as a method of mechanical pre-amplification in nonlinear vibration energy harvesting systems. However, despite their advantages, most current PE systems are limited to degenerate parametric operation within a narrow frequency band around the primary instability tongue. In this paper, we simulate and experimentally demonstrate a parametrically driven capacitive electromechanical resonator having multiple electrical degrees of freedom. Multiple modes allow for several frequency bands in which the electrical resonator is driven into nondegenerate (combination) parametric resonance (PR) in addition to degenerate resonance, thereby enabling operation over a broader range of frequencies while maintaining the same mechanical footprint. These frequency bands and PR thresholds are tunable by simply changing the electrical circuit parameters and PR can be achieved in the presence of high mechanical damping making the method more adaptable than purely mechanical approaches. Experimental results are extended by simulations indicating that proper selection of operating parameters can enable the merging of instability tongues to produce a broadband region of PR for elastic wave energy harvesting thereby obtaining superior performance when compared to an equivalent single degree of freedom PE energy harvester.
Finite-time quantum Stirling heat engine
Authors: Hamedani Raja S , Maniscalco S , Paraoanu G S , Pekola J P , Lo Gullo N 
Published: February 2021

Abstract
We study the thermodynamic performance of a finite-time non-regenerative quantum Stirling-like cycle used as a heat engine. We consider specifically the case in which the working substance (WS) is a two-level system (TLS). The Stirling cycle is made of two isochoric transformations separated by a compression and an expansion stroke during which the WS is in contact with a thermal reservoir. To describe these two strokes we derive a non-Markovian master equation which allows to study the real-time dynamics of a driven open quantum system with arbitrary fast driving. Following the real-time dynamics of the WS using this master equation, the endpoints of the isotherms can deviate from the equilibrium thermal states. The role of this deviation in the performance of the heat engine is addressed. We found that the finite-time dynamics and thermodynamics of the cycle depend non-trivially on the different time scales at play. In particular, driving the WS at a time scale comparable to the resonance time of the bath enhances the performance of the cycle and allows for an efficiency higher than the efficiency of the quasistatic cycle, but still below the Carnot bound. However, by adding thermalization of the WS with the baths at the end of compression/expansion processes one recovers the conventional scenario in which efficiency decreases by speeding up the processes. In addition, the performance of the cycle is dependent on the compression/expansion speeds asymmetrically, which suggests new freedom in optimizing quantum heat engines. The maximum output power and the maximum efficiency are obtained almost simultaneously when the real-time endpoints of the compression/expansion processes are considered instead of the equilibrium thermal endpoint states. However, the net extractable work always declines by speeding up the drive.
A path integral approach to electronic friction of a nanometer-sized tip scanning a metal surface
Authors: Wang Yang , Jia Yu 
Published: February 2021

Abstract
In this work, we study the dissipation mechanism and frictional force of a nanometer-sized tip scanning a metal surface via a path integral approach. The metal, with internal degrees of freedom (c, c
†) and a tip with an internal degree of freedom (d, d
†) couple with one another by means of an exchanged potential, V. Having integrated out all internal degrees of freedom, we obtain the in-out amplitude. Moreover, we calculate the imaginary part of the in-out amplitude and the frictional force. We find the imaginary part of the in-out amplitude to be positive, and correlated to the sliding velocity in most cases. The frictional force is proportional to the sliding velocity for the case where v < 0.01. However, for cases where v > 0.01, the frictional force demonstrates nonlinear dependence on sliding velocity.
Infinitely many nonlocal symmetries and nonlocal conservation laws of the integrable modified KdV-sine-Gordon equation
Authors: Liang Zu-feng , Tang Xiao-yan , Ding Wei 
Published: February 2021

Abstract
Nonlocal symmetries related to the Bäcklund transformation (BT) for the modified KdV-sine-Gordon (mKdV-SG) equation are obtained by requiring the mKdV-SG equation and its BT form invariant under the infinitesimal transformations. Then through the parameter expansion procedure, an infinite number of new nonlocal symmetries and new nonlocal conservation laws related to the nonlocal symmetries are derived. Finally, several new finite and infinite dimensional nonlinear systems are presented by applying the nonlocal symmetries as symmetry constraint conditions on the BT.
On the uncertainties in the realization of the kelvin based on thermodynamic temperatures of high-temperature fixed-point cells
Authors: Todd A D W , Anhalt K , Bloembergen P , Khlevnoy B B , Lowe D H , Machin G , Sadli M , Sasajima N , Saunders P 
Published: February 2021

Abstract
In July 2016 the Consultative Committee for Thermometry’s Non-Contact Thermometry Working Group formed a task group to compile a complete list of uncertainties for high-temperature fixed points, categorize them as well specified or not, and recommend areas of future research. We describe herein two paths to realizing T by indirect primary radiometry using high-temperature fixed-point blackbody cells: one in which published values for the metal–carbon eutectic material transition temperatures are used and the other where a set of cells has their transition temperatures determined directly. The uncertainty components that need to be considered for each path are given together with typically achievable values and how well those values are known. This work concentrates on Co–C, Pt–C and Re–C.
Research on Influencing Factors of Power Grid Security Risk Based on “Cognitive-Constraint” Model
Authors: Yu Lei , Lv Jin , Peng Qiwei , Zhao Linying , Li Gang 
Published: February 2021

Abstract
With the improvement of the intelligent level of the power grid, the operation safety of the power system has received extensive attention. The current accident analysis mostly relies on the experience of personnel, which is prone to omissions. Firstly, this article analyzes the safety risk factors of power grid accidents from four aspects: man factors, equipment factors, management factors, and environmental factors based on the accident causes theory. Secondly, the fault tree model is used to explore the mechanism of each failure factor and quantify the structural importance of each event. Finally, summarize the rules of accidents and make reasonable suggestions for scientifically and reasonably avoiding similar accidents and building a safe power grid.
Research on Modeling and Simulation of Smart Substation Cyber-Physical System Considering Coupling Analysis
Authors: Yang Huifeng , Chen Liandong , Cheng Kai , Li Gang , Wang Xinying 
Published: February 2021

Abstract
With the rapid development of Internet of Things and communication technologies, substations are becoming more intelligent, which brings opportunities for cyber attacks, threatens the safety of substations, and the high coupling of equipment in substations increases the threat. This paper analyzes and studies the information-physical characteristics and equipment coupling problems of smart substations, constructs a smart substation CPS model based on the balance equation of state quantity, and designs a line fault simulation example to verify the stability of the model.
Analysis on the Layout and Capacity Adaptability of China’s Coastal Iron Ore Unloading Terminals
Authors: Yao Haiyuan , Wang Dachuan , Li Yijun , Su Mengchao , Tang Guo-lei 
Published: February 2021

Abstract
As the most important raw material for the iron and steel industry, demand for iron ore is rapidly recovering with the steady recovery of domestic machinery, manufacturing and other iron and steel-related industries. Recently, the number of ore ships waiting to berth has increased significantly at the major iron ore unloading ports along the coast of China. Factors, such as weather influences and concentrated arrivals, make the problem of port ore ships under pressure reappear. This article describes the overall situation of China’s iron and steel market and coastal iron ore transportation and analyzes the characteristics of iron ore import transportation in various regions. The construction layout, stockpiling situation conditions and the capacity adaptability of China’s iron ore terminals are systematically studied. And it proposes that the specialized ore unloading terminals generally need to meet the demand of foreign trade imports. However, the capacity of the Bohai Rim, the Yangtze River Delta and the regions are-as along the coast is still tight, and the local port pressure is still prominent. In the future, further research and the optimization of China’s iron ore unloading terminal system should be done. Through AIS dynamic data monitoring, port and shipping big data mining and analysis, and the other new technical means, the adaptability of iron ore unloading capacity at terminal is refined research, the peak arrival of ships and other situations are properly handled, and China’s iron ore foreign trade Import transportation is protected stablly and safely.
Study on Scheme Optimization of bridge reinforcement increasing ratio
Authors: Shuai Song , Xili Qi , Shiyong Cao , Yi Xu , Huiying Ou , Hongbo Tao , Xiaoxu Huang 
Published: February 2021

Abstract
The bridge reinforcement methods, each method has its advantages and disadvantages. The load-bearing capacity of bridge members is controlled by the ultimate strain of concrete in the compression zone or the ultimate strain of reinforcement in the tension zone, so the selection of the bridge reinforcement method is affected by the section reinforcement ratio. When the reinforcement ratio of the section is between the minimum reinforcement ratio and the critical reinforcement ratio, we should choose the beam bottom reinforcement plan; when the section reinforcement ratio is between the critical reinforcement ratio and the maximum reinforcement ratio, it should be adopted Reinforcement method of bridge deck reinforcement layer.