bluuebunny/crossref_metadata_2025 huggingface dataset:
Combined fabrication of terahertz hollow-core metal rectangular waveguide cavity using electrochemical deposition and selective chemical dissolution
Authors: Bi Xiaolei , Meng Lingchao
Published: February 2022

The terahertz hollow-core metal rectangular waveguide cavity is a typical terahertz rectangular cavity structure that has several advantages and is widely used. However, the fabrication of the terahertz hollow-core metal rectangular waveguide cavity with high working frequency has not made recent breakthroughs, especially when the working frequency is 1-THz and above. In this paper, a combined process of electrochemical deposition and selective chemical dissolution is proposed first to manufacture the terahertz hollow-core metal rectangular waveguide cavity with high working frequency. Taking the fabrication of a 1.7-THz hollow-core metal rectangular waveguide as an example, the manufacturing methods and experiments of each step are described systematically. A terahertz hollow-core metal rectangular waveguide cavity with an end face size of 81.9 × 162.7 µm2, the edge radius less than 10 µm, the internal bottom surface roughness less than 0.08 µm, and the internal side surface roughness less than 0.3 µm is obtained. These experimental results are matched with the processing requirements of a 1.7-THz hollow-core metal rectangular waveguide. This flexible and controllable combined process makes it possible to manufacture more types of terahertz hollow-core metal rectangular cavity structures with high working frequency.
Effects of anisotropy on the transition to absolute instability in a porous medium heated from below
Authors: Celli M. , Barletta A.
Published: February 2022

The emerging instability of a forced throughflow in a fluid saturated horizontal porous duct of rectangular cross section is investigated. The duct is heated from below by assuming the horizontal boundaries to be at different temperatures. Both the horizontal and the vertical boundaries are impermeable and the basic flow is parallel to such boundaries. The porous medium is anisotropic with different permeabilities in the vertical and horizontal directions. The effect of anisotropy on the onset of buoyancy-driven modal instability and absolute instability is analyzed. The parametric conditions leading to the instability of the basic flow are determined by employing an analytical dispersion relation. The different permeabilities in the vertical and horizontal directions turn out to play opposite roles in the onset of modal instability and in the transition to absolute instability. It is shown that an increasing vertical permeability has a destabilizing effect, while an increasing horizontal permeability has a stabilizing effect.
Superposition strategies: How and why White people say contradictory things about race
Authors: Hughey Matthew W.
Published: February 2022

Due to the centrality of race and racism in social, economic, and political life, coupled with the racially privileged position of White people, the assessment of White racial attitudes is an ongoing concern. There is a great deal of survey-based, quantitative work that demonstrates a compelling case of White attitudinal polarization—a grouping of authoritarian, racist attitudes versus another alliance of progressive, antiracist attitudes—an increasingly racialized culture war. However, other studies, largely qualitative and open-ended, demonstrate the heterogeneous, shifting, and hypocritical nature of White discourse about race. To resolve this paradox, I refrain from the assumption that White racial “attitudes” are essentially bifurcated, while I also refuse the contention that White people produce spontaneous narratives whole-cloth. Rather, I argue that with sustained attention to time, context, and triangulation, we can better understand how and why White people speak of People of Color in positive ways one moment and negative the next, marshaling both to defend, rationalize, or improve their racialized subject position. I argue that these contradictions are—à la Schrödinger’s famous thought experiment—“superposition strategies.” Both racist and antiracist attitudes are simultaneously alive and dead in the same individual or group. Contradictory White discourse helps maintain a sense of self-efficacy and coherent White racial identity within conflictual and politically supercharged social situations, as well as within racially unequal social structures.
Glycosite-deleted mRNA of SARS-CoV-2 spike protein as a broad-spectrum vaccine
Authors: Wu Chung-Yi , Cheng Cheng-Wei , Kung Chih-Chuan , Liao Kuo-Shiang , Jan Jia-Tsrong , Ma Che , Wong Chi-Huey
Published: February 2022

Significance

To contain the spread of SARS-CoV-2, the mRNA vaccine of viral spike protein has proven to be highly effective, although the efficacy against the emerging variants is decreasing. Here, we show that the mRNA of spike protein with deletion of glycosites in the RBD or especially the S2 domain to expose more conserved epitopes can be used as a broadly protective vaccine against the wild type and variants of concern. The spike protein translated from such mRNA was not properly folded, and thus induced cell apoptosis and a strong T cell response. Our findings demonstrate the importance of the glycosylation effect on the development of broadly protective mRNA vaccines.
Sinful wives and queens
Authors: Alfie Fabian
Published: February 2022

The author of theDivine Comedy, Dante Alighieri (1265–1321), dealt with “sodomites” twice in his masterpiece, once inInfernoand again inPurgatorio. In their examinations of the passage inInferno, literary critics have typically conflated the modern-day definition of “homosexual” with the medieval “sodomite.” In order to see how Dante viewed non-normative sexuality accurately, however, it is necessary first to uncouple the medieval term “sodomite” from today’s term, “homosexual,” and to apply instead the medieval definition of the former. Numerous sources of Dante’s time indicate that “sodomy” did not mean, strictly speaking, same sex practices between men, but rather it encompassed a wide array of sexual activities. The same is probably true of the sodomites in Dante’sInferno, some of whom might not have bedded other men. Examination of the passage inPurgatorio, moreover, indicates a greater degree of subtlety in Dante’s thought regarding non-normative sexual attraction.
Plurilingualism, multimodality and machine translation in medical consultations
Authors: Piccoli Vanessa
Published: February 2022

This contribution deals with the use of Google Translate as one among many resources that participants mobilize to
overcome the language barrier in plurilingual medical consultations. It is grounded on a two-hour interaction involving a family
of Albanian asylum seekers newly arrived in France and a French general practitioner. To reach mutual comprehension, participants
rely on the mediation of a lay interpreter (one of the family’s children) who translates for the doctor and the other family
members. In this interaction, English is used as a lingua franca, while machine translation is conducted between French and
Albanian. The analysis will focus on the interactional work that participants accomplish in order to: (1) propose or solicit the
use of Google Translate and make the computer accessible to all participants; (2) detect and repair misunderstandings caused by an
unsuitable translation.
Applying augmented feedback in basketball training facilitates improvements in jumping performance
Authors: Leukel Christian , Gollhofer Albert
Published: February 2022

Augmented feedback, which is feedback about movement characteristics provided by an external source, can facilitate performance improvements. Results from recent studies, in which information about the jumping height were presented, indicated increased jumping performance due to augmented feedback. In the present study we aimed to utilize augmented feedback about the jumping height in regular basketball training. Therefore, augmented feedback was implemented and part of the training regime, and information about the jumping height was displayed while subjects performed catch and shoot exercises with the basketball. 18 subjects (9 with augmented feedback, 9 without augmented feedback) practiced for 3 weeks (9 training sessions). The subjects receiving augmented feedback, but not subjects in the control group, displayed increased jumping heights of countermovement‐jumps and drop‐jumps after the training. The ground contact times of countermovement‐jumps and drop‐jumps were not significantly changed after training. The number of successful hits, indicating ball performance, did also not change after training. Thus augmented feedback had no detrimental effect on sport‐specific performance. The unchanged ground contact times of drop‐jumps in combination with increased jumping heights indicate increased efficiency of stretch shortening cycle contractions. According to the positive effect of augmented feedback on jumping performance and the simplicity with which it was integrated into the training regime we recommend this method for regular basketball training.

Highlights

Augmented feedback about the jumping height in basketball training facilitated jumping height of countermovement‐jumps and drop‐jumps.

The ground contact times were not altered, suggesting increased efficiency of the stretch‐shortening cycle during jumping.

According to the positive effect and its simple implementation augmented feedback is recommended for regular basketball training.
Body-worn enzymatic biofuel cell with automated pencil drawn bioelectrodes for energy harvesting from human sweat
Authors: U S Jayapiriya , Goel Sanket
Published: February 2022

Epidermal bioelectronics is a field of integrated electronic system which consists of conductive materials used in a variety of applications with external energy supply. Arguably, biofuel cells, which can produce energy directly from the physiological environment, are the best power sources for wearable bioelectronics. Optimized electrode materials, which are highly flexible, light-weight and disposable, are an key features to be considered. In this work, a novel method of developing enzymatic bioelectrode using automated pencil strokes for biofuel cell application is discussed. The developed lactate/O2 biofuel cell shows a maximum power density of 11.5 µW cm−2 and 7.8 µW cm−2 in the presence of lactate and human sweat, respectively with high open-circuit voltage. This cost-effective and straightforward electrode fabrication technique delivering enhanced performance without any metallic catalyst is commendable for future wearable devices.
SAT-assembly: a new approach for designing self-assembling systems
Authors: Russo John , Romano Flavio , Kroc Lukáš , Sciortino Francesco , Rovigatti Lorenzo , Šulc Petr
Published: February 2022

We propose a general framework for solving inverse self-assembly problems, i.e. designing interactions between elementary units such that they assemble spontaneously into a predetermined structure. Our approach uses patchy particles as building blocks, where the different units bind at specific interaction sites (the patches), and we exploit the possibility of having mixtures with several components. The interaction rules between the patches is determined by transforming the combinatorial problem into a Boolean satisfiability problem (SAT) which searches for solutions where all bonds are formed in the target structure. Additional conditions, such as the non-satisfiability of competing structures (e.g. metastable states) can be imposed, allowing to effectively design the assembly path in order to avoid kinetic traps. We demonstrate this approach by designing and numerically simulating a cubic diamond structure from four particle species that assembles without competition from other polymorphs, including the hexagonal structure.
Bone anatomical landmark localization with cascaded spatial configuration network
Authors: Zhao Qijie , Zhu Junhao , Zhu Junjun , Zhou Anwen , Shao Hui
Published: February 2022

Accurate localization of bone anatomical landmarks in medical images is of great significance for decision-making in surgical plans and orthopedic surgery visual navigation systems development. However, due to the high dimensionality and large size of medical images, current automatic anatomical landmarks detection methods still have issues in terms of accuracy, robustness, and efficiency. To improve the accuracy of bone anatomical landmark detection in medical images, a new network model with a two-step strategy (coarse localizing and fine localizing) was proposed in this study. By combining fully convolutional neural networks and the heatmap regression model, a cascaded spatial configuration network was designed to combine the global and local features of 3D image features and localize anatomical landmarks stepwise. The model was evaluated with a collected knee CT image dataset and a published spine CT image dataset. The results were compared to existing state-of-the-art models. The proposed method outperformed other models with an average error of 1.31 mm for knee landmarks and 5.31 mm for the localization of spine landmarks. The outlier rates at error radius 3 mm, 5 mm, and 7 mm are also smaller compared with other models, indicating good robustness of the model. Our proposed method provides a new neural network model with reasonably good accuracy and robustness with a limited computational cost for landmark localization tasks.
Low-cost remote distance and height sensing analog device for laboratory agriculture environments
Authors: Sotner Roman , Polak Ladislav , Jerabek Jan
Published: February 2022

This paper introduces a novel simple readout system for infrared distance measurement and transmission in closed environments, for instance small-area agriculture, employing transformation of distance on settable duty cycle variation. This simple analog system utilizes active devices fabricated in 0.35 μm 3.3 V I3T25 ON Semiconductor complementary metal oxide semiconductor process. Analog system generates and transmits the information in form of the duty cycle of square wave signal with frequency of 3 kHz up to 46.6 kHz in full range (duty cycle approximately between 10% and 90%) or half range (above 50%) due to requirements of various types of receivers. There is no requirement for any special processing software. The transmitted waveform is received by a low-cost phototransistor in distance at least 30 mm (case when the transmitter and receiver are placed directly on both sides of dividing glass plate). The proposed concept was tested for distance measurement (up to 70 mm) by commercially available distance sensor connected to the communication system and can be utilized for different use cases (e.g. monitoring of growth of small plants or mushrooms). The measuring range (sensitivity and dynamical range) of the sensing system can be easily adjusted. The experiments indicate error between the transmitted and received value below 5%. The overall error of the system between the evaluated and real measured distance is below 10%. All the presented tests confirmed operationability of the proposed system.
Dynamic light scattering based on low-cost components
Authors: Talaván Daniel , España Samuel
Published: February 2022

A dynamic light scattering (DLS) instrument has been assembled using low-cost components. This setup includes an inexpensive laser diode, a silicon photomultiplier including amplifier electronics, a digital oscilloscope, and a regular computer. A set of latex nanoparticles with different sizes has been used to fully characterize the instrument for multiple acquisition configurations. In addition, results were compared to those obtained by transmission electron microscopy and a commercial DLS equipment including gold and iron oxide nanoparticles. The size measurements performed with the DLS instrument resulted very robust for multiple acquisition configurations with and error typically below 1%. A very good agreement was obtained when comparing the results with the values obtained with reference techniques. Therefore, accurate and reproducible size measurements can be performed with the DLS instrument developed in this work for a wide range of nanoparticle sizes and materials while significantly reducing the cost.
Constructing MIL-101(Cr) membranes on carbon nanotube films as ion-selective interlayers for lithium–sulfur batteries
Authors: Zhang Feng , Gao Yuan , Wu Feichao , Li Lin , Li Jingde , Wang Guirong
Published: February 2022

It is of significant importance to suppress the polysulfide shuttle effect for the commercial application of lithium–sulfur batteries. Herein, continuous MIL-101(Cr) membranes were successfully fabricated on carbon nanotube films utilizing a simple in situ growth method, aiming at constructing interlayer materials for inhibiting the shuttle effect. Owing to the suitable pore aperture and super electrolyte wettability, the as-developed MIL-101(Cr) membrane can effectively inhibit the shuttle behaviour of polysulfides while allowing the fast transport of Li-ions simultaneously, working as an ionic sieve. Additionally, this MOFs membrane is also helpful in accelerating the polysulfide catalytic conversion. Therefore, the proposed interlayer delivers an extraordinary rate capability, showing a remarkable capacity of 661.9 mAh g−1 under 5 C. Meanwhile, it also exhibits a high initial capacity of 816.1 mAh g−1 at 1 C and an exceptional durability with an extremely low capacity fading of 0.046% per cycle over 500 cycles.
Performance enhancement of gas sensing by modification of molybdenum selenide nanosheets with metal nanoparticles
Authors: Liu Shuai , Liu Yinggang , Li Hanxiao , Bai Yu , Xue Jiale , Xu Ruojun , Zhang Min , Chen Guoxiang
Published: February 2022

In this paper, nanostructured molybdenum selenide (MoSe2) with composited phases are synthesized by hydrothermal method, and the products are modified by metal anoparticles to improve the gas sensing performance. Microstructure characterization shows that few layered 1T/2H-MoSe2 nanosheets have been successfully prepared. Both the morphology and component of nanosheets could be tuned by the reaction parameters. It is shown the MoSe2-based nanomaterials have excellent selectivity to nitrogen dioxide (NO2) according to gas sensing properties measurement. The sensitivity of 1T/2H-MoSe2 nanosheets modified by Cu nanoparticles is 17.73 (50 ppm NO2) at the optimal operating temperature, which is the highest compared with other samples. The sensors also exhibit rapid response/recovery time and high stability. The sensing mechanism of MoSe2 nanosheets toward NO2 is investigated based on the first-principles calculation. The results suggest the modification by metal nanoparticles could significantly improve the adsorption energy and charge transfer between gas molecule and MoSe2. This work demonstrates a promising guidance for the design of new NO2 gas sensing materials and devices.
Review on 3D growth engineering and integration of nanowires for advanced nanoelectronics and sensor applications
Authors: Hu Ruijin , Yu Linwei
Published: February 2022

Recent years have witnessed increasing efforts devoted to the growth, assembly and integration of quasi-one dimensional (1D) nanowires (NWs), as fundamental building blocks in advanced three-dimensional (3D) architecture, to explore a series of novel nanoelectronic and sensor applications. An important motivation behind is to boost the integration density of the electronic devices by stacking more functional units in the out-of-plane z-direction, where the NWs are supposed to be patterned or grown as vertically standing or laterally stacked channels to minimize their footprint area. The other driving force is derived from the unique possibility of engineering the 1D NWs into more complex, as well as more functional, 3D nanostructures, such as helical springs and kinked probes, which are ideal nanostructures for developping advanced nanoelectromechanical system (NEMS), bio-sensing and manipulation applications. This Review will first examine the recent progresses made in the construction of 3D nano electronic devices, as well as the new fabrication and growth technologies established to enable an efficient 3D integration of the vertically standing or laterally stacked NW channels. Then, the different approaches to produce and tailor more sophisticated 3D helical springs or purposely-designed nanoprobes will be revisited, together with their applications in NEMS resonators, bio sensors and stimulators in neural system.
Simulation for multiwavelength large-aperture all-silicon metalenses in long-wave infrared
Authors: Hao Junbo , Ma Ting , Ye Zilin , Chen Chen , Yang Dahai , Zhou Keya , Wang Yiqun , Jin Peng , Lin Jie
Published: February 2022

Long-wave infrared imaging systems are widely used in the field of environmental monitoring and imaging guidance. As the core components, the long-wave infrared lenses suffer the conditions of less available materials, difficult processing, large volume and mass. Metalens composed of sub-wavelength structures is one of the most potential candidates to achieve a lightweight and planar optical imaging systems. Meanwhile, it is essential to obtain large-aperture infrared lenses with high power and high resolution. However, it is difficult to use the finite-difference time-domain method to simulate a large-aperture metalens with the diameter of 201 mm due to the large amount of computational memory and computational time required. Here, to solve the mentioned problem, we firstly propose a simulation method for designing a large-aperture metalens, which combines the finite-difference time-domain algorithm and diffraction integration. The finite-difference time-domain algorithm is used to simulate the meta-atom’s transmitted complex amplitude and the one-dimensional simplification of the diffraction integral is to calculate the focused field distributions of the designed metalens. Furthermore, the meta-atom spatial multiplexing is applied to design the all-silicon metalenses with the aperture of 201 mm to realize dual-wavelength (10 and 11 μm) achromatic focusing, super anomalous dispersion focusing and super normal dispersion focusing. The designed metalenses are numerically confirmed, which reveal the feasibility of all-silicon sub-wavelength structures to accomplish the multiwavelength dispersion control. The designed all-silicon metalenses have the advantage of lightweight and compact. The proposed method is effective for the development of large-aperture imaging systems in the long-wave infrared.
Investigating the thermal stability of metallic and non-metallic nanoparticles using a novel graphene oxide-based transmission electron microscopy heating-membrane
Authors: Batra Nitin M , Mahalingam Dinesh K , Doggali Pradeep , Nunes Suzana P , Costa Pedro M F J
Published: February 2022

In recent years, graphene has been explored as a heating membrane for studying high-temperature dynamics inside the transmission electron microscope (TEM) due to several limitations with the existing silicon nitride-based membrane. However, the transfer of monolayer graphene films for TEM experiments is challenging and requires many complicated steps with a minimum success rate. This work developed a novel in situ heating platform by combining the graphene oxide (GO) flakes in the pre-patterned chips. The isolated GO flake was self-suspended between the metal electrodes by a simple drop-casting process. The GO was reduced and characterized using Raman and electron energy-loss spectroscopy. Furthermore, a GO-based heater was used to investigate the thermal stability of gold and silica nanoparticles. The gold nanoparticles evaporated non-uniformly and left an empty carbon shell, while silica disappeared uniformly by etching carbon support. We successfully demonstrated a GO flake as a heating membrane to study high temperature thermal dynamic reactions: melting/evaporation, agglomeration, Rayleigh instability, and formation/or removal of carbon in the nanoparticles.
μs and ns twin surface dielectric barrier discharges operated in air: from electrode erosion to plasma characteristics
Authors: Nguyen-Smith R T , Böddecker A , Schücke L , Bibinov N , Korolov I , Zhang Q-Z , Mussenbrock T , Awakowicz P , Schulze J
Published: February 2022

Electrode erosion through continual long-timescale operation (60 min) of identical twin surface dielectric barrier discharges (twin SDBDs) powered either by a microsecond (μs) or a nanosecond timescale (ns) voltage source is investigated. The twin SDBDs are characterized using current–voltage measurements, optical emission spectroscopy, and phase integrated ICCD imaging. The temporally and spatially averaged gas temperature, consumed electric power, and effective discharge parameters (reduced electric field, and electron density) are measured. The μs twin SDBD is shown to operate in a filamentary mode while the ns twin SDBD is shown to operate in a more homogeneous mode (i.e. non filamentary). Despite a similarity of the effective discharge parameters in both the μs and ns twin SDBD, erosion of the nickel coated electrodes caused by operation of the twin SDBD differs strongly. Only the formation of a moderate number of nickel oxide species is observed on the surface of the ns twin SDBD electrodes. In contrast, the nickel coated electrodes are locally melted and considerably higher densities of oxides are observed around the eroded areas of the μs twin SDBD, due to the filamentary nature of the discharge.
Application of edge detection based on hexagonal image structure to delamination detection of carbon fiber reinforced polymer material
Authors: Chen YongQiang , Luo Kai , Chen Liang , Weng Haobo , Liang Wei
Published: February 2022

Delamination is one of the most critical damage modes in carbon fiber reinforced polymer (CFRP) materials, and is invisible to the naked eye. Although delamination defect images of CFRP materials can be obtained through ultrasonic tomography, it is still difficult to accurately identify the position and contours of defect images. In this study, four different delamination defect images of CFRP composite plates were obtained through a finite element simulation and fan-beam ultrasonic tomography. A hexagon algorithm based on interpolation is proposed that transforms the reconstructed defect images from square pixels into hexagonal pixels. The interpolation algorithm is based on the overlap between the square and hexagonal pixels. As the experiment results verify, the use of the hexagonal structure-based morphological method for edge detection significantly reduces the recognition error from 7.74% to 0.148% in comparison with a traditional quadrilateral structure. The experimental results also showed that this method can effectively reduce the artifact interference and obtain complete and accurate target edge information more effectively than a square structure.
Structural design of flexible interdigital capacitor based upon 3D printing and spraying process
Authors: Tu Zhige , Xia Zhidong , Luo Weichu , Huang Pei , Lin Jian
Published: February 2022

Traditional substrates of metallic interdigital electrodes (IEs) are rigid and undeformable, flexible interdigital capacitors are therefore appealing as strain sensors. In this study, interdigital capacitors were parametrically designed by 3D printing and encapsulated by spraying process. The interdigital circuits of the structure were printed with conductive silicone rubber filled with silver-coated glass fiber and carbon fiber, and the circuits were encapsulated with polydimethylsiloxane. Herein, the interdigital-flexible structures were parametrically designed and firstly served as capacitive sensor, namely flexible interdigital capacitive sensors (FICSs). The spaces between IEs, are extremely sensitive to strain, therefore provide the capacitors with excellent electromechanical behaviors. The optimized FICS benefited for a wide working range of strain (0%∼45%), high sensitivity (gauge factor = 2.7) to a tiny strain of 0.3%, stable working duration at different stretching speeds (18 mm min−1, 36 mm min−1 and 72 mm min−1), prolonged service life (>800 cycles), as well as excellent capability to detect human movement (bulging, grasping and bending). Response mechanism of the FICS was modeled based upon its microstructure evolution, including the distances between IEs and the fillers migration. The printed FICSs with optimized structure provide a comprehensive thought in the design of electronics, further would inspire the branch of 3D printed electronics.
Comment on ‘Angles in the SI: a detailed proposal for solving the problem’
Authors: Leonard B P
Published: February 2022

Paul Quincey makes a compelling argument for recognizing angle as a base quantity with the radian as the base unit. Solid angle is then a derived quantity with the steradian a coherent derived unit equal to one square radian. The author demonstrates how familiar equations of rotational motion appear to result from dimensionally consistent explicit-radian equations by ‘setting the radian equal to one’—which he calls the radian convention. Quincey also claims, based (solely) on assumed analogies with translational motion, that for rotation, the so-called ‘improved’ units for torque, angular momentum and moment of inertia must be J/rad, J/(rad/s) and J/(rad/s)2, respectively, and that the conventional units (N m, kg m2 s−1 and kg m2) result from application of the radian convention to these quantities. However, based on fundamental physical principles, I show here that, although the radian convention may help in understanding a confusing notational change applied to angular displacement and its time derivatives when comparing explicit-radian equations to their equivalent familiar forms, it cannot be applied to torque, angular momentum or moment of inertia. The dimensionally correct SI units for these quantities are, respectively, the well-established angle-independent units: newton metre, kilogram metre-squared per second and kilogram metre-squared.
Reply to Comment on ‘Angles in the SI: a detailed proposal for solving the problem’
Authors: Quincey Paul
Published: February 2022

The comment by Leonard (2022 Metrologia
59 038001) primarily proposes that if angle is treated as a base quantity, with the radian as its base unit, it would be wrong to change the units for torque (from N m to J rad−1), angular momentum (from J s to J s rad−1) and moment of inertia (from kg m2 to kg m2 rad−2), as was proposed in the letter being commented on (Quincey 2021 Metrologia
58 053002). This reply clarifies the situation by looking directly at the consequences of the two proposals. Apart from the comfort of retaining the familiar units for these quantities, the benefit of Leonard’s proposal would be the preservation of a few favoured equations used in specific situations, while the general relationships between many physical quantities would need to change. The revised units proposed in the letter would leave all the established general relationships unchanged, and are the best option for allowing the longstanding problem of angles being wrongly treated as numbers within the SI to be resolved. This reply includes some historical context, which describes how Euler implicitly introduced the idea that ‘the radian is another name for the number one’ into the mathematics used for rotating objects, at a time long before anyone had thought about unit systems.
Space charge compensation of positive ion beams used in magnetic fusion applications
Authors: Holmes A.J.T. , McAdams R.
Published: February 2022

A model is presented for space charge neutralisation of positive ion beams. The model is used for the particular case of the beams used for magnetic based fusion applications. The beams consist, after a gas neutraliser, of ions and atoms at different energies. Account is taken of the contribution of all beam components to ionization of the background gas. Consideration is also given to not only beam heating of the plasma generated by the beam, due to Coulomb collisions, but also to Coulomb heating by fast electrons produced in ionization by all beam particles and stripping of the neutral components. Two approximations are considered for the motion of the secondary ions out of the beam potential; a drift approximation and a freefall approximation. All the beam plasma parameters can be calculated. The model is applied to a typical extracted beam of deuterium ions of 120 kV, 60 A. It is found that these beams are very highly compensated and that beam plasma heating by the electrons produced is generally greater than that due to the beam ions.
Large-scale collecting mirrors for ITER optical diagnostic
Authors: Samsonov D. , Tereschenko I. , Mukhin E. , Gubal A. , Kapustin Yu. , Filimonov V. , Babinov N. , Dmitriev A. , Nikolaev A. , Komarevtsev I. , Koval A. , Litvinov A. , Marchii G. , Razdobarin A. , Snigirev L. , Tolstyakov S. , Marinin G. , Terentev D. , Gorodetsky A. , Zalavutdinov R. , Markin A. , Bukhovets V. , Arkhipushkin I. , Borisov A. , Khripunov V. , Mikhailovskii V. , Modestov V. , Kirienko I. , Buslakov I. , Chernakov P. , Mokeev A. , Kempenaars M. , Shigin P. , Drapiko E.
Published: February 2022

The challenges of a large-scale mirror design for the in-vessel collection system of ITER divertor Thomson scattering (DTS) are under consideration. These are the mirrors located out-of-line vision of fusion plasma (so called ‘second mirrors’) with a high-reflective Ag-based coating. The paper outlines: approaches providing optical surface shape and angular position stability; Ag coating applicability for ITER in-vessel environment, including resistance to accidental steam ingress. The proposed solutions may also appear to be of some use in other ITER diagnostics and in diagnostics of other fusion devices.
The synergetic effects of three-dimensional magnetic perturbations and finite beta on collisionless trapped electron mode in tokamak plasmas
Authors: Huang Zhangsheng , Guo Weixin , Wang Lu
Published: February 2022

The effects of three-dimensional (3D) magnetic perturbations (MPs) and finite beta (β, i.e., the ratio of plasma kinetic pressure to magnetic pressure) on the instability of collisionless trapped electron mode (CTEM) have been studied. Based on the local 3D equilibrium model, we have derived general expressions for longitudinal invariant and the corresponding precession drift frequency of trapped electrons, which include the synergetic effects of MPs and finite β. It is found that 3D effects can either stabilize or destabilize CTEM instability by analytically solving the linear dispersion relation of CTEM. These effects depend on the poloidal and toroidal mode numbers as well as the phase of 3D MPs. Specially, for the destabilizing phase of MPs, the stabilizing effect of finite β on CTEM can be even reversed when the displacement of magnetic flux surface exceeds a critical value. Moreover, the synergetic effects of 3D MPs with stabilizing phase and finite β can further reduce the required absolute value of negative magnetic shear to completely stabilize CTEM instability. This indicates that 3D MPs might be used as an actuator for lowing the level of anomalous electron heat transport, and thus facilitate the formation of electron internal transport barrier (eITB).
Illustrating the physics of core tungsten (W) transport in a long-pulse steady-state H-mode discharge on EAST
Authors: Shi Shengyu , Chen Jiale , Jian Xiang , Odstrčil Tomáš , Clarrisse Bourdelle , Wu Muquan , Wu Mingfu , Duan Yanmin , Chao Yan , Zhang Ling , Cheng Yunxin , Qian Jinping , Garofalo Andrea M. , Gong Xianzu , Gao Xiang , Wan Yuanxi , EAST Team the
Published: February 2022

The behavior of core tungsten (W) in a pure radio-frequency-heated long-pulse steady-state H-mode discharge in the Experimental Advanced Superconducting Tokamak (EAST) with an ITER-like divertor (ILD) is analyzed using experimental diagnostic data and modeled using a combination of drift-kinetic neoclassical and gyro-fluid turbulent software. In the steady state, the experimental core line-averaged W concentration (C
W) is about 2 × 10−5, which is evaluated using the intensity of the W unresolved transition array (W-UTA) spectral structure in the region of 45–70 Å (which is composed of W
27+–W
45+ line emissions) through spectroscopy in the extreme ultraviolet region. W produces a peak of the radiated power density profile around a normalized radius of ρ ∼ 0.3. Therefore, W does not centrally accumulate in the experiment. A time slice of the steady-state is modeled, which accounts for both the neoclassical and turbulent transport components of W based on the self-consistent background plasma profiles simulated by TGYRO (Candy et al 2009 Phys. Plasmas
16 060704). It is found that turbulent transport dominates over neoclassical transport for W. In addition, the turbulent diffusion coefficient is large enough to offset the sum of the neoclassical and turbulent pinch (convection) velocities, so that the W density profile for a zero particle flux is not strongly peaked. By combining TGLF (Staebler et al 2017 Nucl. Fusion
57 066046) and NEO (Belli and Candy 2008 Plasma Phys. Control. Fusion
50 095010; 2012 Plasma Phys. Control. Fusion
54 015015) for the W transport coefficient with the impurity transport code STRAHL (Dux 2006 STRAHL User Manual), the experimental C
W and the information radiated by W can be reproduced closely. In addition, the effect of toroidal rotation on the W transport is also clarified.
Analysis of CO2 Emissions from Low Strength Recycled Concrete
Authors: Yang Huijun , Li Yuexia , Ji Chao
Published: February 2022

In this paper, we determined the calculation boundary of CO2 emissions from low strength recycled concrete, and calculated the CO2 emissions from the low strength recycled broken brick concrete RC15 with the target strength of 15 MPa and the ordinary concrete C15, as well as the proportion of CO2 emissions from each material of the low strength recycled concrete. The results showed that the low strength recycled concrete had less CO2 emissions. The results of the proportion of CO2 emissions from each material of the low strength recycled concrete showed that cement was in the largest proportion and other materials were in a smaller proportion.
Allocation of Energy Storage Capacity Based on Optimal Power Flow
Authors: Jiang Minglei
Published: February 2022

Under the continuous development of new power system, the double high characteristics become more and more obvious in the characteristics of power system. How to make good use of electrochemical energy storage and participate in the power market has become an urgent problem to be solved. In view of this, based on the day ahead market forecast,this paper establishes a model for the participation of electrochemical energy storage in the operation of the electricity market and sets up three different scenarios with the goal of maximizing gross profit. Finally, it is concluded that the operation strategy of electrochemical energy storage proposed in this paper can effectively improve the benefits of electrochemical energy storage.
Resource Integrated Urban Design Method and Mathematical Model in Regulatory Detailed Planning
Authors: Yuan Li
Published: February 2022

In order to promote the rationality of urban resource integration process, an urban resource integration method based on repeated game control scheme is proposed in the Article. Firstly, construct the optimal model of urban integration decision-making, quantify the operation level of dominant factor, consider the hardware and software strength for urban resource integration; secondly, a repeated game control scheme is proposed in the Article, in which the algorithm is based on Nash bargaining solution and the finite repeated game process, which could fully optimize the optimal model of urban integration decision-making; lastly, verify the effectiveness of proposed methods by simulation examples.
Research On the Characteristics of Sediment and the Release Law of Nitrogen and Phosphorus Pollutants in Landscape Lake
Authors: Zhu Zhaoliang , Zhou Hao , Li Qi , Zou Jiale , Liu Mengmeng
Published: February 2022

Under the premise that the external input of nitrogen and phosphorus is controlled, the endogenous release has become the dominant factor of lake eutrophication. In order to understand the degree of eutrophication of the landscape lake and the release of nitrogen and phosphorus in the sediment, a sediment lake in Jinan was used as a test object,three sampling points were set near the inlet, outlet and reed bushes of the landscape lake to collect water samples. And sediment samples, the three indicators of TN, NH4+-N and TP in the water body and TN, NH4+-N, TP, pH, DW, LOI in the sediment were analyzed. Release of TN, NH4+-N and TP in sediments under different temperature, pH, dissolved oxygen (DO), and disturbance conditions. The results show that both elevated temperature and low DO can accelerate the release of nitrogen and phosphorus in the sediment, while high DO can inhibit the release of N and P in the sediment; acidic conditions are favorable for the release of TN and NH4+-N, and alkaline conditions are favorable for TP release; disturbance can accelerate the release of nitrogen in the sediment, but has little effect on total phosphorus release.
The Design of Four Channel TR Module for Ku Band
Authors: Wang Yi , Ji Shuai , Guan Yang
Published: February 2022

This paper presents the design and development of four channel digital TR module for Ku band.The four channel TR module for Ku band consists of consists of digital part and RF part. DDS, TR control, AD, DDC and echo transmission constitute the digital transceiver part of the digital TR module. Two-stage frequency conversion and filtering, circulator, limiter, multi-stage LNA and multi-stage PA constitute the the RF transceiver part of the digital TR module. At present, the digital TR module has completed the program design, production and processing, testing.
Design of Multi-channel Real-time Signal Acquisition System
Authors: Wang Yi , Zhang Meng , Ji Shuai , Wang Jingdong
Published: February 2022

In order to improve the accuracy of the real-time signal acquisition, a real-time signal acquisition system based on high speed ADC and FPGA is proposed in this paper. AD9208 is used to realize high speed acquisition and DDC processing of original signal. FPGA 7V690T is used to realize digital channelization and fine FFT processing. This system can realize massive data storage and real-time signal display. The test results show that this system can effectively realize real-time signal acquisition and processing, and has strong anti-interference ability.
A miniaturized seven-electrode conductivity and temperature integrated sensor
Authors: Sun Wei , Guo Fengxiang , Chai Xu , Hu Ding , Zhang Xueyu , Xu Mingxia , Wang Yibao , Wang Shaoyan , Wu Xiaofan , Qu Chuang , Gai Zhigang
Published: February 2022

Marine environmental monitoring technology is the support of marine development, and its development level and innovation capability have become important criteria for measuring a country’s marine science and technology indicators. In order to meet the application demand of large-scale and high-density deployment of marine observation network, a planar open seven-electrode conductivity and platinum resistance temperature integrated sensor is developed by using Micro Electro Mechanical System(MEMS) technology, combined with semiconductor micro and nano precision processing technologies such as mask lithography and physical sputtering. The measurement principle, probe design preparation, packaging and calibration method of this conductivity temperature sensor are presented. By calibrating and fitting the measurement data of this sensor, good measurement accuracy results were obtained. The miniaturized conductivity temperature sensor has the advantages of small size, low power consumption, low cost and high accuracy of probe processing, high batch consistency, and fully meets the application requirements of marine observation network.
Optimization Design and Development of UHF Antenna for PD Detection in Substation
Authors: Xing Zhen-hua , Wang Zhen , Xu Hang , Xu Miao , Mou Xiao-lin , Wu Lu-xiao , Yang Kun , Liu Zhao
Published: February 2022

In this paper, a directional logarithmic periodic antenna is designed to meet the application requirements of local discharge detection in substation.The model of log-periodic dipole antenna was established by using high frequency electromagnetic wave simulation software, and the effects of dielectric substrate thickness, dielectric constant of dielectric substrate and patch size parameters on antenna return loss and standing wave ratio were analyzed.Finally, the dielectric substrate thickness of the antenna is 1.6mm, the material is TEflon, and the width of the assembly line is 4mm.According to the selected antenna type and size, the uHF signal receiving antenna is manufactured.
Implementation of Fast Huffman Encoding Based on FPGA
Authors: Shan Yongxin , Chen Xin , Qiu Cao , Zhang Ying
Published: February 2022

In order to improve the efficiency of JPEG encoding architecture, some imagine compression systems use pipeline technology. Different modules will spend different cycles in the image compression, so the pipeline is prone to blockage. This paper proposes uses doublebyte splicing output Huffman code architecture and double Huffman encoding units on FPGA, so that Huffman encoding process spent less clock cycles in JPEG encoding, and pipelined JPEG encoding algorithm can be encoded in real time without blocking. According to the FPGA verification, although the number of logic units used will increase, Huffman encoding takes less clock cycles.
An Optimization method for the Internet of vehicles oriented to moving relay
Authors: Liang Cai
Published: February 2022

Moving relay (MR) is a relay node deployed on public transportation such as cars and trains, which can effectively combat the vehicle penetration loss (VPL) problem in vehicle communication. outage probability (OP) is an expression of link capacity. When the link capacity cannot meet the required user rate, an outage will occur. For the downlink multi-user network, we compared the performance of direct transmission and MR-assisted transmission with the probability of interruption as a performance indicator. Subsequently, we design a joint optimization scheme for transmission mode selection and user scheduling, select the transmission mode suitable for the user, schedule the user with the largest information rate, and derive the closed-form expression of the scheduling scheme. And compared with random selection scheduling. The experiment compares random scheduling with the scheduling scheme we proposed. Experimental results show that compared with random selection and scheduling scheme, the proposed scheduling scheme can reduce OP, thereby improving system performance.
A pointer meter reading recognition method based on improved ORB algorithm for substation inspection robot
Authors: Liu Zhe , Huang Hua , Wang Na , Cao Yingshuang , Zeng Liang , Zhang Jianhuan , Zhang Chentao
Published: February 2022

Currently, pointer meters in substations are read manually, which causes a waste of human resources. To realize automatic reading of such meters, an accurate method for recognizing and reading of pointer meters was proposed for the inspection robot in substation. The new method consists of three steps. Step 1: the image is preprocessed with grayscale, noise reduction and piecewise linear grayscale transformation. Step 2: the Gaussian scale space is used to enhance the scale invariace of the ORB algorithm. Meanwhile, the RANSAC algorithm is used to screen the matching point pairs, which improves the accuracy of the feature pointer matching. Step 3: the Hough transform algorithm is utilized to fit the pointer. Finally, the reading result is obtained according to the angle method and the prior information of the pointer meter. The proposed approach can recognize and read the meter accurately. It has high reliability and engineering application value.