bluuebunny/crossref_metadata_2025 huggingface dataset:
Maximizing the electronic charge carriers in donor-doped hematite under oxygen-rich conditions via doping and co-doping strategies revealed by density functional theory calculations
Authors: El-Gibally Hoda , Shousha Shehab , Allam Nageh K. , Youssef Mostafa
Published: April 2022

The low electronic conductivity of hematite (α-Fe2O3) limits its best performance in many applications. Though highly reducing conditions induce an intrinsic n-type behavior, reaching extremely low oxygen partial pressure (pO2) values is not practical. Alternatively, certain dopants provide hematite with excess electrons at practical pO2 values. This study employs density functional theory with thermodynamic analysis to compute the concentration of electronic defects in hematite as a function of pO2, upon doping with 1% of 3d, 4d, and 5d transition metals. Isothermal Kröger–Vink diagrams at 1100 K are plotted to reveal the charge compensation mechanism controlling the electronic carriers in doped hematite and the maximum attainable pO2 value, which achieves approximately one electron per dopant. A higher pO2 value is a metric for an effective donor. Ti, Zr, Hf, Nb, Ta, Mo, and W are shown to be effective donors, especially Nb, Ta, and W, which achieve a 1:1 electron/dopant ratio around atmospheric pressure and a maximum electron/dopant ratio greater than one. The latter is a new metric introduced in this study to quantify the doping efficacy of a donor. Moreover, our study shows that W, Ta, and Nb co-doping in specific percentages with any of the other investigated dopants ensures the n-type behavior of the co-doped hematite while opening the possibility of improving other properties via the other dopant. The other dopant can be Ni or Co to enhance the surface catalytic properties or Zn to increase the minority hole carriers. Both properties are desirable in applications such as photoelectrochemical cells.
Algorithm of auto-balancing noise-canceling based on noise correlation for high-speed balancing, high-dynamic range, and robustness against DC-offset drift
Authors: Seto Keisuke , Kobayashi Takayoshi , Tokunaga Eiji
Published: April 2022

The influence of the light source noise can be reduced by subtracting the signal of the light source noise (reference signal) from that of the probe light (probe signal). Here, it is essential that the intensities of the signals are equated. To equate the intensities, an auto-balancing method is widely employed, where the gain of the probe signal is feedback-controlled, regarding the DC component in the subtraction as an error signal. However, DC-offset drift causes a deviation from the optimal intensity balance. Additionally, the DC component is often several orders of magnitude larger than the sample signal, which requires a high-dynamic range in the circuitry. Furthermore, if the feedback control is too fast, it cancels out the sample signal. In this study, we formulate a noise correlation auto-balancing method, where the correlation of the reference signal and residual noise in the subtraction is employed as the error signal. With this scheme, all the above problems are avoided. The feasibility of the algorithm was demonstrated by a prototype circuitry and signals emulating the probe and reference signals. It did not suffer from the DC-offset drift, while a 44-dB canceling rate with auto-balancing of a 1.3-MHz cutoff frequency was demonstrated. We foresee, such as in pump/probe measurements, that this scheme improves the robustness, dynamic range, and response time required to follow changes in transmittance and the measurement position of the sample while employing a light source that is advantageous in wavelength selectivity, coherence, and cost but is noisy.
Transient analysis of photomultiplication-type organic photodiodes
Authors: Bai Songxue , Li Ruiming , Huang Huihuang , Qi Yiming , Xu Yalun , Song Jiannan , Yao Fang , Sandberg Oskar J. , Meredith Paul , Armin Ardalan , Lin Qianqian
Published: April 2022

Photomultiplication-type organic photodetectors have emerged as a class of next generation solution-processed photodetectors with high gain. Despite this promising feature, the reported photodectors still suffer from relatively large dark currents at high bias voltages. To overcome this drawback, a mechanistic understanding of the photomultiplication effect in organic photodiodes is required. In this work, we advanced the performance of photomultiplication-type organic photodetectors by tuning the active layer composition and interfacial layers. The optimized devices exhibit small dark currents and flat dark current–voltage curves under the reverse bias condition up to −10 V. The optimized photodetectors also reached an ultra-high responsivity of 23.6 A/W and the specific detectivity of 1.04 × 1012 Jones at −10 V. More importantly, we investigated the photomultiplication process with multiple transient techniques and revealed that the photoconductive gain effect is a slow process, which relies on the photo-Schottky effect enabled by charge carrier tunneling and the accumulation of holes. Furthermore, we also demonstrated prototypical pulsed-light detection based on the optimized devices, which showed great potential for real applications.
Segmented vortex wavefront coherent beam combining
Authors: Jabczynski Jan K. , Gontar Przemyslaw , Gorajek Lukasz , Zendzian Waldemar
Published: April 2022

A concept of a coherent beam combining with a segmented vortex wavefront (V-CBC) was proposed to generate a dark optical trap. Three-dimensional (3D) irradiance distributions in the caustics of V-CBC were modeled. The properties of the V-CBC were compared with those of the classical vortex beams. The impact of random phase disturbances on the V-CBC was preliminarily analyzed.
Bootstrap estimation of the effect of instrument response function uncertainty on the reconstruction of fusion neutron sources
Authors: Lamb Kevin M. , Geppert-Kleinrath Verena , Birge Noah W. , Danly Christopher R. , Divol Laurent , Fittinghoff David N. , Freeman Matthew S. , Pak Arthur E. , Wilde Carl H. , Zylstra Alex B. , Volegov Petr L.
Published: April 2022

Neutron imagers are important diagnostics for the inertial confinement fusion implosions at the National Ignition Facility. They provide two- and three-dimensional reconstructions of the neutron source shape that are key indicators of the overall performance. To interpret the shape results properly, it is critical to estimate the uncertainty in those reconstructions. There are two main sources of uncertainties: limited neutron statistics, leading to random errors in the reconstructed images, and incomplete knowledge of the instrument response function (the pinhole-dependent point spread function). While the statistical errors dominate the uncertainty for lower yield deuterium-tritium (DT) shots, errors due to the instrument response function dominate the uncertainty for DT yields on the order of 1016 neutrons or higher. In this work, a bootstrapping method estimates the uncertainty in a reconstructed image due to the incomplete knowledge of the instrument response function. The main reconstruction is created from the fixed collection of pinhole images that are best aligned with the neutron source. Additional reconstructions are then built using subsets of that collection of images. Variations in the shapes of these additional reconstructions originate solely from uncertainties in the instrument response function, allowing us to use them to provide an additional systematic uncertainty estimate.
Single-shot phase retrieval based on anisotropic metasurface
Authors: Zhou Hongqiang , Li Xin , Ullah Naqeeb , Geng Guangzhou , Li Junjie , Li Xiaowei , Wang Yongtian , Huang Lingling
Published: April 2022

Phase retrieval is a generic calculating phase method through intensity images and prior conditions. Usually, the image recording system requires stable mechanical movement and accurate alignment between different phase-shift images, which greatly limits the imaging speed and stability, resulting in mismatch or low phase retrieval quality. In this work, we propose a single-shot polarization-sensitive phase retrieval developed from triple transport of the intensity method with anisotropic metasurface. By applying gradient phase along the interface, three images with diffractive phase differences are projected on the recording plane. The three images are formed with known diffraction distances due to the conjugate Pancharatnam−Berry phase modulation of metasurface. The recorded images are calculated and post-processed using transport of intensity equation technique to obtain the phase of object. As a proof-of-principle, we demonstrate the phase imaging results through measuring phase-only objects with single-shot capture. Compared to traditional transport-of-intensity equation optical systems, our method requires no mechanical or system tuning, and polarization or electric controller switching. Thus, it can acquire three differently focused images with single-shot. This significantly improves the time efficiency of the experiments. Such compact metadevice with simplified manipulation and easy post-processing for phase retrieval can be applied to various applications, such as optical microscopy, fluid measurement, and on-ship integration.
Development of mixed modeling method to obtain parameter distributions in a high-speed propulsion combustion system
Authors: Ruyi Tao , Shenshen Cheng
Published: April 2022

The gas–solid flow state of the high-speed combustion system varies with the propellant combustion and the movement of the projectile. In this paper, to accurately obtain the motion characteristics and flow field distribution in the chamber, a mixed calculation model of interior ballistic two-phase flow combined with the particle element method and the two-fluid method was established. First, considering the different states of the combustion system in different periods, the particle element method was used to describe the initial charging state, while the two-fluid method was used to calculate the subsequent homogeneous flow. Next, the coupling and transformation of the two methods were realized by the boundary mapping. Finally, the mixed modeling method was validated by comparing the classic code results. Based on the novel approach, parameter distributions in the high-speed combustion chamber are obtained, and the particle movement and the development of the flow field in the chamber are described accurately. In the initial stage of ignition and flame-spreading, the flame front and heat transfer process appear completely. With the movement of the projectile, the flow field in the chamber changes drastically, and the particles gather toward the bottom of the projectile. When the propellant is burned out, the uniform distribution in the chamber is presented. The results indicate that the proposed method may be promising for a novel idea to obtain accurate parameter distributions in interior ballistic.
A radio-frequency Bose–Einstein condensate magnetometer
Authors: Cohen Y. , Maddox B. , Deans C. , Marmugi L. , Renzoni F.
Published: April 2022

We report on a radio frequency magnetometer employing a Bose–Einstein condensate of 87Rb atoms held in a dipole trap. An AC sensitivity of 296 pT/Hz is achieved at a probing volume of 3.2×10−8 cm3, leading to a volume-normalized sensitivity of 53 fT/Hz cm−3. At larger probing volumes with the atoms released from the magnetic trap used in the initial phase of the evaporation sequence, the AC sensitivity is improved to 1.4 pT/Hz, allowing a two-mode approach for applications requiring improved sensitivity. Immediate application in high-resolution electromagnetic induction imaging is expected when compared to performance of other induction-based imaging platforms.
Great Southern Reef
Authors: Venzo Paul , Francis Prue , James Cate
Published: April 2022

Have you heard of the Great Southern Reef?
Join Professor Seaweed and her friends Frankie and Sam to learn more about one of Australia's best kept secrets!
The Great Southern Reef spans thousands of kilometres along the coast from northern New South Wales to Western Australia. It is home to giant kelp forests and fascinating animals such as rock lobsters, sea snails and sponges. Explore the sandy beaches with this inquisitive trio, and discover marine curiosities that are washed up along the coast after a big storm.
You may be inspired to go beachcombing yourself, to learn and care about the animals and seaweed that you find!
Reading level varies from child to child, but we recommend this book for ages 6–9.
Patterns of specialist out-of-pocket costs for Australian Medicare services: implications for price transparency
Authors: Chalmers Kelsey , Elshaug Adam G. , Pearson Sallie-Anne , Landon Bruce E.
Published: April 2022

Objective To explore out-of-pocket (OOP) costs within specialties and individual specialists, and use of Medicare Benefits Schedule (MBS) data for potential price transparency initiatives. Methods We conducted a cross-sectional descriptive study of claims for a 10% random sample of Medicare enrolees for out-of-hospital MBS-billed subsequent and initial consultations between 1 January 2014 and 31 December 2014, specific to cardiologist, oncologist and ophthalmologists (with at least 10 patient visits in 2014). Our main outcomes were the number of locations per provider, number of unique OOP consultation costs per provider and provider-location, and the proportion of bulk-billed visits for these visits. Results We studied 970 cardiologists, 913 ophthalmologists and 376 oncologists. At least 67% of specialists across each specialty had at least two practice locations: cardiologists had a median of three (interquartile range [IQR]: 2–4) and ophthalmologists and oncologists both had a median of two (IQR: 1–3). For subsequent consultations, cardiologists had a median of three unique costs per location (IQR: 2–3), whereas ophthalmologists had a median of four unique costs per location (IQR: 3–5). In contrast, oncologists had a median of one unique cost per location (IQR: 1–2) (57.6% of oncologists’ provider-locations charged only the bulk-billing amount). Conclusions Specialists have distinct fee lists that can vary based on location. Summary statistics on price transparency websites based on a single amount (like a median or mean OOP charge) might mask substantial variation in costs and lead to bill shock for individual patients.
Freeze-thaw cycles enable a prebiotically plausible and continuous pathway from nucleotide activation to nonenzymatic RNA copying
Authors: Zhang Stephanie J. , Duzdevich Daniel , Ding Dian , Szostak Jack W.
Published: April 2022

Significance

The replication of RNA without the aid of evolved enzymes may have enabled the inheritance of useful molecular functions during the origin of life. Template-directed RNA copying is a posited step in RNA replication. Key steps on the path to copying of RNA templates have been studied in isolation, including chemical nucleotide activation, generation of a key reactive intermediate, and template-directed polymerization. Here we report a prebiotically plausible scenario under which these reactions can happen together under mutually compatible conditions. Thus, this pathway could potentially have operated in nature without the complicating requirement for exchange of materials between distinct environments.
The narrowing of literature use and the restricted mobility of papers in the sciences
Authors: Varga Attila
Published: April 2022

Significance

A narrower range of literature is being read as citations are concentrating more on top papers. This is a long-standing trend, present since 1970. Citation concentration may lead to a less flexible scholarly communication system, whereby novel findings have a harder time resurfacing. In line with this argument, the popularity of a paper is more predictable today based on its previous citation impact. I present a mechanism of cumulative advantage that links increased concentration to the restricted mobility of papers. Citations are more dispersed from the 1990s, in the sense that papers are more likely to be cited at least a few times. Information technologies to disseminate papers are likely behind this latter trend.
Ancient DNA gives new insights into a Norman Neolithic monumental cemetery dedicated to male elites
Authors: Rivollat Maïté , Thomas Aline , Ghesquière Emmanuel , Rohrlach Adam Benjamin , Späth Ellen , Pemonge Marie-Hélène , Haak Wolfgang , Chambon Philippe , Deguilloux Marie-France
Published: April 2022

Significance

By integrating genomic and archaeological data, we provide new insights into the Neolithic French monumental site of Fleury-sur-Orne in Normandy, where a group of selected individuals was buried in impressively long monuments. The earliest individuals buried at Fleury-sur-Orne match the expected western European Neolithic genetic diversity, while three individuals, designated as genetic outliers, were buried after 4,000 calibrated BCE. We hypothesize that different, unrelated families or clans used the site over several centuries. Thirteen of 14 of the analyzed individuals were male, indicating an overarching patrilineal system. However, one exception, a female buried with a symbolically male artifact, suggests that the embodiment of the male gender in death was required to access burial at the monumental structures.
Electronic, optical and magnetic characteristics of V doped BeS
Authors: Ambreen Hina , Aldaghfag Shatha A , Yaseen Muhammad , Iqbal Javed , Zahid Muhammad , Dahshan A , Hegazy H H
Published: April 2022

Electronic, magnetic and optical features of V doped BeS compound are obtained with FP-LAW technique. A comparative investigation is performed among electronic band structure (BS), total and partial density of states (PDOS) is presented with 6.25, 12.5, 18.75 and 25% concentration of V. The results of electronic BS and density of states (DOS) show half metallic ferromagnetic (HMF) behavior with direct band gap (Eg). The calculated Eg are 2.8, 2.9, 3.3 and 3.7 for Be0.9375V0.0625S, Be00875V0.125S, Be0.8125V0.1875S and Be0.75V0.25S, respectively. For the optical feedback of TM doped BeS material, the imaginary and real part of dielectric function

ε

ω

has been studied with the absorption coefficient, extinction coefficient, reflectivity, optical conductivity, and refractive index up to 15 eV. It is noted that with the increment of Eg, the static dielectric constant increases. Furthermore, the magnetic characteristics of resultant compound are examined. The HMF nature of TM doped BeS in electronic and magnetic properties may makes resultant compounds a potential candidate for optical and spintronic appliances.
Scattering amplitude and two-body loss of ultracold alkaline-earth atoms in a shaking synthetic magnetic field
Authors: Yang Shu , Chen Yue , Zhang Peng
Published: April 2022

The idea of manipulating the interaction between ultracold fermionic alkaline-earth (like) atoms via a laser-induced periodical synthetic magnetic field was proposed in Kanász-Nagy et al (2018 Phys. Rev. B 97, 155156). In that work, it was shown that in the presence of the shaking synthetic magnetic field, two atoms in 1S0 and 3P0 states experience a periodical interaction in a rotated frame, and the effective inter-atomic interaction was approximated as the time-averaged operator of this time-dependent interaction. This technique is supposed to be efficient for 173Yb atoms which have a large natural scattering length. Here we examine this time-averaging approximation and derive the rate of the two-body loss induced by the shaking of the synthetic magnetic field, by calculating the zero-energy inter-atomic scattering amplitude corresponding to the explicit periodical interaction. We find that for the typical cases with shaking angular frequency λ of the synthetic magnetic field being of the order of (2π) kHz, the time-averaging approximation is applicable only when the shaking amplitude is small enough. Moreover, the two-body loss rate increases with the shaking amplitude, and is of the order of 10−10 cm3 · s−1 or even larger when the time-averaging approximation is not applicable. Our results are helpful for the quantum simulations with ultracold gases of fermionic alkaline-earth (like) atoms.
Constraints on cosmic-ray boosted dark matter in CDEX-10 *
Authors: Lei Zhan-Hong , Tang Jian , Zhang Bing-Long
Published: April 2022

Dark matter (DM) direct detection experiments have been setting strong limits on the DM–nucleon scattering cross section at the DM mass above a few GeV, but leave large parameter spaces unexplored in the low mass region. DM is likely to be scattered and boosted by relativistic cosmic rays in the expanding universe if it can generate nuclear recoils in direct detection experiments to offer observable signals. Since low energy threshold detectors using Germanium have provided good constraints on ordinary halo GeV-scale DM, it is necessary to re-analyze 102.8 kg

day data in the CDEX-10 experiment assuming that DM is boosted by cosmic rays. For the DM mass range 1 keV

1 MeV and the effective distance within 1 kpc, we reach an almost flat floor limit at

cm2 for the spin-independent DM–nucleon scattering cross section, at a 90% confidence level. The CDEX-10 result is able to close the gap unambiguously in the parameter space between the MiniBooNE and XENON1T constraints, which were partially hindered by the Earth attenuation effect. We also quantitatively calculate the expected neutrino floor on searching for CRBDM in future direct detection experiments using Germanium.
106 New Emission-line Galaxies and 29 New Galactic H ii Regions are Identified with Spectra in the Unknown Data Set of LAMOST DR7
Authors: Lu Yan , Luo A-Li , Wang Li-Li , Wang You-Fen , Li Yin-Bi , Han Jin-Shu , Qin Li , Tang Yan-Ke , Qiu Bo , Zhang Shuo , Zhang Jian-Nan , Zhao Yong-Heng
Published: April 2022

This work is to retrieve emission-line spectra from the “Unknown” data set in LAMOST DR7 V1.2, most of which are low signal-to-noise ratios spectra. In the work, we perform emission line search and redshift calculations on the Unknown data set to get possible emission line galaxy spectra. Taking the galaxy spectra released by LAMOST as templates, the Product Quantization (PQ) based approximate nearest neighbor (ANN) search is used to retrieve the nearest neighbors of each spectrum. We keep the spectra for which the calculated redshift and the published redshift of the template meet the threshold, and 16,188 spectra with emission lines are obtained from the LAMOST DR7 Unknown data set. After visual inspection of spectra 10,266 spectra are left, in which 5828 spectra are identified as emission-line galaxies, 1782 spectra show ionization nebula features, and other 2656 are not clearly classified. Among 5828 spectra, 5720 can be found in Strasbourg astronomical Data Center catalog, Sloan Digital Sky Survey catalog, or NASA/IPAC Extragalactic Database catalog. The 108 spectra (corresponding to 106 unique coordinates of R.A. and decl.) which have no record in these three databases are new discoveries; for the 1782 spectra showing ionization nebula features, most of them have radial velocities less than 150 kilometers per second. We check them with the latest version of WISE H ii catalog V2.0 (short for HIICat V2) and 985 out of the 1782 spectra belong to 72 H ii regions. Of these H ii regions, 43 were previously identified while the other 29 are newly identified in this work including 797 newly observed spectra. Besides, there are still 2656 spectra that cannot be clearly classified although they have obvious emission lines and with small redshift. Finally, 106 new emission-line galaxies and 29 new Galactic H ii regions are identified, and we conclude that the ANN method sped up by the PQ algorithm is efficient in solving the problem of pairing spectra with massive data set to figure out their classes. We present our result at the link http://paperdata.china-vo.org/LY_paper/Work2/pressWork2_last.zip.
PASTE: FPGA-based Portable At-speed Scan Test Equipment
Authors: Luo Min , Hu Chunmei , Yin Xingyi , Wang Yaohua , Zhao Zhenyu , Hu Xiao
Published: April 2022

The increasing integration and complexity of chips driven by Moore’s Law has placed higher demands on chip verification and testing efforts. Automated Test Equipments (ATE) in conjunction with design for testability can effectively screen out faulty chips, but ATE is too costly and can be functionally redundant to be practical for small and medium-sized chip design companies and scientific research in universities. Therefore, in recent years, there has been a lot of research work on FPGA-based low-cost test equipment, but few studies have used the scan test method and have not been able to realize the at-speed test of the chip. In this paper, we propose a portable, low-cost and configurable FPGA-based chip scan test method, which can realize both normal and at-speed test, and can effectively filter the stuck-at faults and transition faults of the chip. We also optimize the test code size via run-length code compression algorithm and achieve a 68.16% compression rate for the test code, which effectively reduces the overall data storage and transmission overhead.
Design and Optimization of Metal Cavity Bandpass Filter and Fragmented Patch Antenna By Combining Simulation Software and Genetic Algorithm
Authors: Li Wenqi , Wong Sai-Wai , Ou-Yang Le , Wang Diji
Published: April 2022

An electromagnetic (EM) structure optimization method based on Genetic algorithm (GA) and EM simulation software is proposed. The aim is to accelerate optimization speed of electromagnetic structure and improve designed performance. An algorithm considered continuous and discrete problems is adopted to expand design domain of electromagnetic structures. In order to evaluate the performance of proposed method, a fourth-order cavity bandpass filter and a fragmented patch antenna are considered as two examples to verify the analysis.
A Fourth-order Dielectric Narrow-band Bandpass Filter Using Coaxial Resonator
Authors: Wang Diji , Wong Sai-Wai , Li Wenqi
Published: April 2022

In this paper, a compact fourth-order dielectric bandpass filter is proposed. The filter adopts the mode of linear coupling and is composed of four coaxial resonators and two coupling slots, which are fed by two probes, and the four coaxial resonators are resonated to form a passband. The resonant frequency can be controlled by the radius and height of the resonators, and the inter-cavity coupling is controlled by the width of the coupling windows formed by the coupling slots. At last, the simulation results of the filter show that the filter has narrow bandwidth and good in-band matching performance and out-of-band suppression.
Implementation and Verification of Steganography IP Core Based on HLS and OpenCV
Authors: He J J , Sun W , Jiang H
Published: April 2022

Steganography is a safe transmission method that hides secret data in public information to avoid attacks as much as possible. However, the current steganography research and application mainly stay in the software stage. Although the secure transmission of data is realized, it is difficult to realize the purpose of high-speed data transmission. This thesis solves this problem with the help of a fully parallel, high-speed and high-bandwidth FPGA. This paper uses HLS to design a steganography IP core that can be applied to FPGA, and uses OpenCV to quickly and effectively verify the IP core. The final result proves that this paper successfully designed a high-performance IP core that can realize steganography, which effectively solves the problem of difficult high-speed transmission of encrypted data. This IP core combines the AXI bus protocol, which not only facilitates data interaction with DDR3 and other devices, but also conducive to the design and optimization of the complete secret data transmission system in the future.
Multi-scale cooperative search simplified particle swarm optimization algorithm and performance analysis
Authors: Zheng Yanling , Wang Zhankui
Published: April 2022

A multi-scale cooperative searching simplified PSO (MSPSO) was put forward to avoid the standard PSO (SPSO) premature, which was put forward by simulating ants working cooperatively in nature. Its particles trajectories were analyzed and its convergence was proved. The numerical experiment indicates that the MSPSO has better searching performance, especially in solving the higher dimensional optimization problems.
An Improved Particle Swarm Optimization Algorithm for Unmanned Aerial Vehicle Route Planning
Authors: Wang Xiaolu , Huang Chen , Chen Fuhao
Published: April 2022

A global path planning method based on improved particle swarm optimization (PSO) algorithm was proposed to find a high quality flight trajectory in three-dimensional complex environment under multiple threats for UAV. The improved path planning algorithm combines the standard PSO with A* method to compensate for the slow convergence rate of PSO. The objective function with multiple constraints of A* method is used to evaluate the quality of the waypoint, and the objective function of PSO algorithm is designed to evaluate the quality of the candidate path. To verify the effectiveness of the improved algorithm, the improved PSO algorithm is used to compare with basic PSO algorithms. The experiment in complex environment shows it has stronger search ability, convergence ability due to the improvement of population diversity and convergence speed.
A FPGA-based Accelerator Implementation for Path Planning using Q_learning Algorithm
Authors: Liu Xiaojuan , Diao Jietao , Li Nan
Published: April 2022

As one of the most classic reinforcement learning, Q_learning has a very wide range of applications in the control filed of robot. Path planning which is the center of robot control has high computation speed requirements for algorithms, so we need to accelerate by hardware while planning path using Q_learning. In this paper, a hardware accelerator architecture based on FPGA is implemented to accelerate Q_learning while used in path planning. And we evaluate our design on Artix-7 DDR3 board, leading to less FPGA resource consumption and swifter computation speed. Comparing to Q_learning which implemented based on CPU, the speed has improved approximately 519 times, achieving the purpose of accelerating the Q_learning algorithm.
Research on High Precision Linear Motor Driving Technology
Authors: Zhu Min , Shang Zhixia
Published: April 2022

Aiming at the problem that the output of motor driver driving linear motor is not stable enough and will be accompanied by large power ripple, which makes the motor speed unstable and has a great impact on the accuracy, a linear driver is designed. The AB power amplifier circuit is mainly used by the linear driver to achieve linear output of current, and the negative current feedback is used to stabilize the output current. For the software part, a program based on ARM is designed to parse the commands of the upper computer and control the hardware circuit according to the commands, so as to achieve specific functions. The test results show that the non-linear error of the power amplifier driver is only 3.6%, and the three-phase sinusoidal current with different frequencies and amplitudes can be output as needed.
Coplanar Dual-Band Dual-Polarized Shared-Aperture Antenna Array For 4/5G Base Station Applications
Authors: Lin Yecong , Wong Sai-Wai
Published: April 2022

A novel dual-band dual-polarized shared-aperture antenna array is presented for fifth generation wireless communication application. This novel antenna array is a combination of a low-band antenna and four high-band antennas. In order to simplify the design model while achieving broadband, antenna working on low-band (from 0.68 to 0.99 GHz) and antenna working on high-band (from 3.3 to 5.1 GHz) are both loop-shape radiator fed by Y-shape feed. Coplanar, dual-band and shared-aperture are resolved by embedding four HB antenna elements in the LB antenna. From simulation, the proposed coplanar antenna array respectively achieves 43% (from 0.68 to 0.99 GHz) and 37% (from 3.3 to 5.1 GHz) impedance bandwidth in the low-band and high-band.
PANDORE: an environmental box for ITk integration tests
Authors: Costanza F. , Allemandou N.G. , Chabanne E. , Cornudet E. , Delebecque P. , Gaglione R. , Jeremie A. , Leveque J. , Massol N. , Mievre I. , Prevost O. , Vilalte S.
Published: April 2022

PANDORE is the environmental box that is going to be used for the quality control of loaded local supports of the ATLAS ITk Pixel Outer Barrel at LAPP (Annecy, France). First PANDORE, its interlock system, diphasic CO2 cooling station, and data acquisition system are described. Subsequently, the results of the qualification tests are shown. Given the complexity of the ITk Pixel Outer Barrel system, several loading sites are going to be needed. By documenting the state-of-the-art of PANDORE, this note aims to help the wide ITk Pixel community in the discussion for standardizing the quality control procedure and equipment of the loaded local supports.
A modular and flexible data acquisition system for a cosmic rays detector network
Authors: Saito G.T. , Leite M.A.L. , Menegasso R. , Kuriyama M.K. , Munhoz M.G. , de Paula R.E.
Published: April 2022

In this paper, we describe a modular data acquisition system developed as the foundation of a cosmic ray detector network. Each detector setup (henceforth referred as a station) is composed of an independent hardware device that can be controlled and read-out through the Internet. This device is designed to acquire and process the signal of up to eight different detector planes. Each of these detector planes uses plastic scintillator slabs that are optically coupled to silicon photomultipliers (SiPM). Within a single station, different geometries and plane orientations are possible using the same baseline design. The main readout is based on a programmable system-on-a-chip (PSoC), a flexible and re-configurable commodity hardware that is used to implement the trigger and timing logic. A Time to Digital Converter (TDC) is used to determine the precise timing of the event relative to a GPS timing signal and to estimate the signal amplitude through the Time-over-Threshold (ToT) method. An auxiliary set of sensors provide environmental information and station detector planes orientation that, together with other operation data, are periodically sent to a server using the MQTT protocol. Data is cached using an in-memory database for online monitoring and further persisted into a SQL database for offline analysis. The server framework is based in software application containers allowing easy replication of the server infrastructure.
A radiation tolerant 12 bit, 160 MS/s data conversion and transmission ASIC for the CMS electromagnetic calorimeter
Authors: Mazza G. , Argirò S. , Dellacasa G. , Mignone M. , Soldi D. , Varela J. , Wheadon R.
Published: April 2022

The readout electronics for the CMS electromagnetic calorimeter is undergoing a re-design in order to cope with the LHC ugrade. In particular, a fourfold increase in the sampling frequency (from 40 to 160 MS/s) is required. Therefore a new readout ASIC has been developed. The ASIC, named LiTE-DTU, is designed in a CMOS 65 nm technology. The LiTE-DTU embeds two 12 bit, 160 MS/s ADCs, a time window based sample selection, lossless data compression and 1.28 Gb/s serialization. An on-chip PLL provides the 1.28 GHz clock required by the ADCs and the serializers from the 160 MHz clock.
Hydrodynamic cavitation through a bio-inspired fast-closing plunger mechanism: experiments and simulations
Authors: Godínez F A , Guzmán J E V , Salinas-Vázquez M , Valdés R , Palacios C , Chávez O
Published: April 2022

Experimental and numerical results are reported for the internal and external flow fields evolving in a bio-inspired snapping plunger. The experimental evidence underlines the nature of the dynamic-coupling between the processes taking place inside and outside the device. Two main structures dictate the properties of the external flow field: a strong jet which is followed by a vortex ring. Internally, complex patterns of cavitating structures are simultaneously produced in the chamber and the venturi-like conduit. We find the cavitation cycle to be suitably described by the Rayleigh–Plesset model and, thus, proceed to characterize the coupling of both fields in terms of the fluctuations of the velocity. All main parameters, as well as the energy released to the fluid during the collapse, are found to be within the same order-of-magnitude of previously known experimental results for isolated bubbles of comparable size.
Diurnal and seasonal patterns of global urban dry islands
Authors: Meili Naika , Paschalis Athanasios , Manoli Gabriele , Fatichi Simone
Published: April 2022

Urban heat islands (UHIs) are a widely studied phenomenon, while research on urban-rural differences in humidity, the so called urban dry or moisture islands (UDIs, UMIs), is less common and a large-scale quantification of the seasonal and diurnal patterns of the UDI is still lacking. However, quantification of the UDI/UMI effect is essential to understand the impacts of humidity on outdoor thermal comfort, building energy consumption, and urban ecology in cities worldwide. Here, we use a set of globally distributed air temperature and humidity measurements (1089 stations) to quantify diurnal and seasonal patterns of UHI and UDI resulting from rapid urbanization over many regions of the world. The terms ‘absolute UDI’ and ‘relative UDI’ are defined, which quantify urban–rural differences in actual and relative humidity metrics, respectively.

Results show that absolute UDI is largest during daytime with the peak humidity decrease in urban areas occurring during late afternoon hours. In contrast, relative UDI is largest during night and the peak urban relative humidity (RH) decrease and vapor pressure deficit (VPD) increase occurs in the late evening hours with values of around −10% to −11% for RH and 2.9–3.6 hPa for VPD between 20–00 local time during summer. Relative and absolute UDIs are largest during the warm season, except for daytime RH UDI, which does not show any seasonal pattern. In agreement with literature, canopy air UHI is shown to be a nighttime phenomenon, which is larger during summer than winter. Relative UDI is predominantly caused by changes in actual humidity during day and UHI during nighttime.
Spatiotemporal analysis of deforestation patterns and drivers reveals emergent threats to tropical forest landscapes
Authors: Jamaludin Johanness , De Alban Jose Don T , Carrasco L Roman , Webb Edward L
Published: April 2022

As deforestation breaches into new tropical frontiers, proactive conservation strategies require a trifecta of information on where deforestation is accelerating (emergent), how drivers of deforestation vary spatiotemporally, and where to focus limited conservation resources in protecting the most integral yet threatened forested landscapes. Here we introduce Emergent Threat Analysis, a process integrating Emerging Hot Spot Analysis of deforestation, visual classification of deforestation outcomes over time, and spatial quantification of contemporary forest condition. We applied Emergent Threat Analysis to tropical Southeast Asia, a global epicentre of biodiversity threatened by deforestation. We found that emergent hot spots (EHS)—a subset of hot spots characterized by strong, recent, and clustered patterns of deforestation—accounted for 26.1% of total forest loss from 1992 to 2018, with deforestation within EHS proceeding at 2.5 times the regional rate of gross loss. Oil palm and rubber plantation expansion were the principal drivers of deforestation within EHS of insular and mainland SE Asia, respectively. Over the study period, oil palm shifted in importance from Sumatra and Sarawak to Papua and Kalimantan, whereas rubber became prominent in Cambodia and Tanintharyi from 2006 to 2015. As of 2019, more than 170 000 km2 of SE Asia’s remaining forest occurred within EHS, of which 21.7% was protected. High and medium-integrity forest constituted 19.2% and 49.1% of remaining EHS forest, respectively, but of these, 35.0% of high-integrity and 23.9% of medium-integrity EHS forest were protected. Because we anticipate that tree plantation expansion will continue to drive deforestation in SE Asia, significantly heightened protection is needed to secure the long-term preservation of high and medium-integrity forest, especially in highly contested forest frontier regions. Finally, as a flexible, integrated process, Emergent Threat Analysis is applicable to deforestation fronts across the global tropics.
Intermediate statistics in singular quarter-ellipse shaped microwave billiards*
Authors: Dietz Barbara , Richter Achim
Published: April 2022

We report on experiments with a flat, superconducting microwave billiard with the shape of a quarter ellipse simulating a singular billiard, that is, a quantum billiard containing zero-range perturbations. The pointlike scatterers were realized with long antennas. Their coupling to the microwaves inside the cavity depends on frequency. A complete sequence of 1013 eigenfrequencies was identified rendering possible the investigation of spectral properties as function of frequency. They exhibit intermediate statistics and are well described by analytical results derived by Bogomolny, Gerland, Giraud and Schmit for singular billiards with shapes that generate an integrable classical dynamics. This comparison revealed a quadratic frequency dependence of the coupling parameter. The size of the chaotic component induced by the diffractive effects of the scatterers was determined by comparison with analytical results derived by Haake and Lenz for an additive random-matrix model, which interpolates between the models applicable for quantum systems with an integrable and chaotic classical dynamics, respectively.
The role of land use/cover type in influencing hydrological component of a watershed in Chancho and Sorga Sub-watersheds, East Wollega Zone, Oromia, Ethiopia
Authors: Megersa Tolera , Nedaw Dessie
Published: April 2022

Watershed hydrology can be influenced by land use/cover types of the study areas. The activities of humans exert more pressure in influencing the natural dynamism of the watersheds and hydrology through continuous and steep slope cultivation of land. The objective of this study was to assess the influences of land use/cover types and slope gradient on hydrological component of a watershed. The hydrological component of a watershed was simulated by SWAT model with arc-GIS where land use/cover map, slope map and hydrological response unit were used as an input. Farmland land has produced more surface runoff and water yield as compared to the other land use types followed by urban land, while Forest and grassland produced less surface runoff and water yield but higher in evapotranspiration, percolation, ground and lateral flow of water than cultivated and urban land. Area of farmland land is more responsive to the change of surface runoff and water yield than others land use/cover types. As farmland land size increases both surface runoff and water yield tends to decrease and had a negative correlation, whereas, other hydrological variables were less responsive to the change in land size. Slope gradient of land use/covers type contributes to the water imbalance of the watersheds. As slope increases surface runoff and water yield also decreases in farmland, grass, and forest land, whereas, increases in urban land as slope increased. The influences of land use/cover types and slope gradient on the watershed hydrology were more observed where human action is high in terms of continuous and steep slope cultivation and urban built-up expansion and appropriate land use and watershed management is paramount important for water balance in the watershed.
Identification of Sambiloto agroecology as a basis for utilization and conservation of germplasm
Authors: Pujiasmanto Bambang , Rumia Manurung Ida
Published: April 2022

Climate change can affect the diversity and growth of tropical plants, one of which is Sambiloto. Sambiloto is a wild plant with medicinal potential that is experiencing scarcity due to climate change in Indonesia. This study aims to identify the agroecological suitability of Sambiloto. The research was carried out using the survey method. The survey method includes the study of description and identification and the distribution pattern of sambiloto. The results showed that Sambiloto could grow at an altitude of 180 – 861 meters above sea level with a temperature of 20.32 °C -26.93 °C, relative humidity 78% - 87%, rainfall 2053.2-3555.6 mm/year. Sambiloto can grow on soils with moderate N, low P, low Mg, very low to low Ca, low to moderate organic C, while the pH is slightly acidic to acidic. The distribution pattern of sambiloto in the middle and lowlands is clustered, while in the highlands, it is uniform. The highest andrographolide content was obtained from sambiloto in the middle plains (2.27%), while in the lowlands (1.37%) and highlands (0.89%). Sambiloto is more commonly found in the middle lands (RD 76.87%, RF 10%, RK 27.75%, IVI 114.62%) than in the lowlands (RD 59.50%, RF 9.09%, RK 31.41%, IVI 99.98%), and highlands. (RD 42.20%, RF 3.88%, RK 11.62%, and IVI 78.21%).
Growth of soybean (Glycine max L.) on various types of biochar
Authors: Nurmalasari A I , Rahayu Muji , Nabila Nur Owena Evita
Published: April 2022

Climate change especially in agriculture, have a serious impact on soil fertility. Low soil fertility can affect the quality and quantity of agricultural produce. Biochar is one of the soil-fixing materials that can be used to increase soil fertility i.e. physical, chemical and biological fertility especially in vertisol soil. The purpose of this research was to find out the influence of various types of biochar and the best dose of biochar on the growth of soybean plants. The research was conducted at Screen House, Faculty of Agriculture, Universitas Sebelas Maret, Surakarta on March to June 2021. The research was designed in randomized complete block design (RCBD) with two factors. The first factor is the type of biochar consisting of three levels, which consist of coconut shell biochar, rice husk biochar, and biochar corn cob. The second factor is the biochar dose consisting of five levels, which consist of 0 ton.ha−1, 5 tons.ha−1, 10 tons.ha−1, 15 tons.ha−1, and 20 tons.ha−1. Each experiment was repeated three times. The results showed no interaction between the type and dose of biochar in all variables. Treatment of the type of biochar rice husk with a dose of 20 tons.ha-1 can increase the plant height by 14.6%. Treatment of the type of rice husk biochar with a dose of 15 tons.ha-1 can increase the number of leaves by 11.345%, the number of branches by 36.63%, wet weight by 17.74%, dry weight by 15.9%. Biochar treatment of coconut shell with a dose of 5 tons.ha-1 can increase the leaf area by 63.45%.
A study of Flickingeria angulata (Blume) A.D.Hawkes and host trees (Phorophytes) at Wilis Mountain, Ponorogo, East Java, Indonesia
Authors: Dwi Yulia Nina
Published: April 2022

Flickingeria angulata (Blume) A.D.Hawkes is one of the species of orchids found in natural habitats in Wilis Mountain, Ponorogo, East Java. This study was aimed to explore, document, and analyze the diversity of Flickingeria angulata at a natural forest area in Wilis Mountain. The method used is an exploratory method by exploring the forest area in the study site. All data of Flickingeria angulata was recorded including its number, host trees and zone at the host tree where this orchid is attached. The result shows that orchid epiphytic F. angulata was found in 6 host tree species, with the two most important species being Pinus merkusii and Schima wallichii. Zone three (bottom part of the branches) was noted as the most preferred zone at host trees to be attached by Flickingeria angulata. Evaluation of these orchid species in natural habitats needs to be done at the same location to determine the impact of climate change.