bluuebunny/crossref_metadata_2025 huggingface dataset:
Switch Mode Power Supply (SMPS) Utilizing Flyback Converter Topology: Simulation and Experiment
Authors: Fauzi F , Zaidi M E , Udom U , Manaf N A A
Published: August 2022

This paper presents simulation and experimental works of a single, 5 volt DC output switch mode power supply (SMPS). The main objective of this work is to design, build and evaluate the SMPS using flyback converter topology. In this work, a 555 timer was chosen as the pulse width modulator. The 555 timer was chosen because it is easily available, cheap and has the capability to produce stable pulse width modulation. The complete circuit of the SMPS consist of full bridge rectifier, smoothing capacitor, pulse width modulator, high frequency transformer and flyback converter. The complete SMPS circuit was firstly designed and simulated using Proteus software. After obtaining acceptable results from the simulation process, the hardware part of the project, soon follows. Next, the SMPS circuit was constructed on a breadbroad. Testing and measurements of important parameters such as the input and output voltages and duty cycle were carried out using digital oscilloscope and multi meter. Both simulation and experimental results have shown that the designed circuit can convert single 24 Vrms 50 Hz AC voltage input into a stable single 5±0.15 V DC outputs. This work also has shown that pulsed DC voltage with peak value of 3.8 V and frequency lower than 4 kHz is adequate in controlling the switching frequency of a MOSFET transistor, thus regulating the output voltage within the desired range. Further analysis also shows close correlation between the simulation and experimental results.
SAR Evaluation of Flexible UWB Antenna for Wearable Applications
Authors: Ashar Dhyey , yadav Ajay Kumar , Sharma Mamta
Published: August 2022

This manuscript appearance a compact and Ultra-Wideband (UWB) antenna for wearable applications. The proposed coplanar waveguide (CPW) feed circular configuration patch antenna is simulated on two different dielectric materials one flexible polyamide based Cordura fabric and other is FR-4, with small footprint of size 36 × 46 mm2. The antenna works in complete UWB band from 3.1 to 10.6 GHz. The performance of the antenna was examined in free space and three-layer human body phantom. This research work also presents the flexibility analysis of structure for both substrates. These examinations exhibited that proposed UWB antenna is an appropriate contender for wireless body area network (WBAN) operation.
Soil mass movement monitoring for landslide detection using low-cost accelerometer sensor as inclinometer
Authors: Kaharuddin S. , Ain M.F. , Mamat M.N. , Abdullah M.N. , Yusob Mohamad Firdaus Bin Mahamad
Published: August 2022

This paper presents soil mass movement monitoring for landslides detection using low-cost MEMS accelerometer as inclinometer. Commercial inclinometers for geotechnical ground observations are quite expensive. This research aims to study and develop low-cost inclinometer as an alternative using accelerometer. The output of the low-cost accelerometer is noisy and fluctuated make it not suitable for accurate measurement device. We solved this problem in this paper using moving average filter. The digital filter algorithm was tested and showed promising results.
Design of ground-mounted grid-connected photovoltaic system with bifacial modules using PVsyst software
Authors: Mohamed NSS , Sulaiman SI , Rahim SRA
Published: August 2022

Bifacial photovoltaic module has gained significant traction in recent years due to its higher irradiation capture capabilities with cost-effective technology. This paper presents the design, simulation, and techno-economic evaluation of a 45MW fixed-tilt ground-mounted grid-connected photovoltaic system with bifacial photovoltaic modules. The site is located in Sungai Petani, Kedah, Malaysia. The PVsyst 7.2 software was used to design the system by selecting the rating of PV module, inverter and tilt angle of PV modules. In addition, shading and loss calculation, as well as performance evaluation, were also conducted using the software. The simulation of the optimal geometrical parameters had shown an optimal tilt angle of 5°, the pitch of 5.5m and PV array installation height of 1.5m with an albedo value of 0.25. Besides, the performance of system with bifacial and monofacial modules were compared in terms of techno-economic performance indicators. The results showed that the bifacial PV system produces higher energy output with a lower levelized cost of electricity when compared to the system with monofacial PV modules.
DC-DC Buck Converter for Electric Bike with Parameterized DC Motor: Simulation and Experimental Validation
Authors: Abdullah M N , Mat Desa M K , Bakar E A , Akhtar M N
Published: August 2022

This paper presents a single stage DC-DC Buck power converter for an electric bike system which is used as a DC motor driver. The DC motor is firstly parameterized to identify and estimate the dynamic of electrical and mechanical parameters. In this paper, the simulation and the experimental validation of the system are presented. A model of a DC-DC Buck converter fed with DC motor is developed. The simulation was carried out using Matlab-Simulink software and the experimental setup is based on a built prototype of Atmega 328 microcontroller board. The similarities of voltage and current input/output waveforms between simulation and experimental results proved that the single stage DC-DC Buck converter with parameterized DC motor suitable to prototype a low power electric bike model.
Ruby Stone Light Grade Inspection System Using CCD Linear Sensor – A Review
Authors: Rahalim F. M. , Jamaludin J. , Raisin S. N. , Asuhaimi F. A.
Published: August 2022

Several gemmology technologies, including loupes, microscopes, and dichroscopes, are currently utilised to assist gemstone traders in evaluating rubies. These tools, on the other hand, rely heavily on human vision for pictorial assessment. There are no standardized tools for determining ruby stone grading, other from those that rely on human vision, which can lead to errors. Gemmologists, stakeholders in the precious stone and manufacturing industries, as well as dental applications, would benefit from a standardized quantitative grading valuation of ruby stones. Extensive research is required to analyse the light characteristics of rubies. This paper presents a potential research overview of the Charge-Coupled Device (CCD) linear sensor to inspect the grading value of ruby stone based on its light characteristic. This research delves deeper into the relevant light properties of rubies for grading purposes. Numerous types of gemmological instruments are used for grading and appraising rubies, as well as their applications, are discussed in this paper. A standardized approach for quantitative grading valuation of ruby stones utilising a Charge-Coupled Device (CCD) linear sensor is offered due to the limits of current techniques and the strong demand for superior quality in the high-valued stone sectors.
Power Controller for Dual-axis Solar Tracking System using PID
Authors: Suboh S M , Er Lim Che , Sardi J
Published: August 2022

Solar energy is one of the rich and unlimited energy sources in Malaysia which can generate power instead of the burning of fossil fuels which can cause air pollution. In this study, a dual-axis solar tracking system is proposed to improve the harvested power. To encourage the maximum output power is produced, PID controller is used. Its function is to achieve the reference power where the angle of the horizontal and vertical axes is considered. The solar radiation is studied from 7 a.m. (0700) to 5 p.m. (1700) according to the habit of solar altitude angle and the azimuth angle in Perlis, Malaysia. There is two PID controllers are developed for the orientation and inclination axis of the solar tracker. The output power between the dual-axis and single-axis of solar tracking system are compared through the simulation in MATLAB Simulink. In conclusion, the dual-axis solar tracker has a better performance than the single-axis solar tracker due to the higher degree of freedom to follow the motion of sun. This maximum power can keep going to the reference power of the photovoltaic module during the greatest radiation of sun depending on the solar altitude and azimuth angle.
Vibration analysis of 28 kHz horn transducer for ultrasonic cleaning based on harmonic response analysis
Authors: Phophayu Suchada , Thongsri Jatuporn
Published: August 2022

The Horn Transducer (HT) is one of the key components in ultrasonic applications, consisting of a front mass, piezoelectric, and back mass parts. Previously, most of the research focused on vibration study of the front mass part based on modal analysis, but the other parts were ignored; therefore, the research results have limitations to actual usage. This research presents the vibration analysis of HT included all parts, based on harmonic response analysis (HRA). First, a conventional HT of 28 kHz, 50 W, 220 V, front mass-radius (R) of 29 mm, and height (H) of 5 mm was investigated for the vibration analysis. Next, proposed designs were also investigated by varying the R as 27 mm - 32 mm, and H as 4 mm - 8 mm. All results were analyzed to find a suitable shape and investigated the designs that affected the vibration. The simulation results revealed that the longitudinal amplitude depends on R and H. In addition, the simulation results were consistent with an experiment and previous work. Finally, the suitable design with R of 29 mm and H of 7 mm provided the optimum vibration at 27,250 Hz. The outcomes of this research were applied to develop a high-performance ultrasonic cleaner.
Development of Electronic Valve Timing Control Unit for Single Piston Expander with Microcontroller
Authors: Ali A. Z. A. , Zakaria M. F. , Mohamad M. N. A. , Muhammad W. N. A. W. , Salim W. S. I. W.
Published: August 2022

An electronic valve timing control unit has been developed mainly for the internal combustion engine operation. This study aims to implement a similar technology into a single-piston expander (SPE) with readily available and low-cost microcontrollers. The study used an Arduino Mega 2560 and ESP32-WROOM microcontrollers to control the valve timing with the rotational input signal obtained from an absolute encoder. The SPE has been expected to run at the rotational speed of up to 2000 rpm. This setup was prepared to simulate the actual SPE operation using a direct current motor to drive the spindle connected to the encoder shaft to create a similar hardware testing and controlled environment. The study aims to identify the efficiency of the microcontroller’s performance with a variation of the valve’s opening and closing time. Results have shown that the clock rate of the microcontroller affects the performance of valve timing response. By increasing the clock rate, the microcontroller can control the valve at a higher speed.
Application of Automated Machine Learning (AutoML) Method in Wind Turbine Fault Detection
Authors: Fadzail N F , Mat Zali S , Mid E C , Jailani R
Published: August 2022

Fault detection has drew much attention nowadays, as it can save time and operational maintenance costs, especially in the wind turbine (WT) that is becoming familiar with renewable energy. Machine learning became widespread use in fault detection methods. However, most available machine learning needs more data and much time to train. Therefore, there is a need to detect faults using a few data during the training process. This paper aims to apply Automated Machine Learning (AutoML) method for fault detection in WT systems. The fault detection in the WT system focuses on the internal stator fault in the generator as it is the main part of the WT. The AutoML model was developed using a neural network (NN) algorithm in python based on the Auto-Keras model. The model was developed using four inputs, i.e. stator and rotor currents in the d-q axis (Iqs, Ids, Iqr
and Idr
) while the outputs are impedance values, i.e. stator resistance, Rs
, and stator inductance, Ls
. The WT system used in this research is the doubly-fed induction generator (DFIG) in MATLAB/Simulink. In the Auto-Keras model, the impedance values (Rs
and L
s) indicated the condition of the DFIG, either normal or fault conditions. Two fault types were applied to the WT system, i.e. inter-turn short circuit and open circuit fault. The Auto-Keras model was trained and tested with the various values of data. The accuracy and the root means square error (RMSE) value of the model were calculated. The result shows that the accuracy is high as it is more than 93% in most conditions, and the RMSE value is low, close to the zero value. Applying the AutoML method in fault detection of the WT system shows its capability to identify faults accurately.
A Comparative Study of Hybrid Energy Storage System using Battery and Supercapacitor for Stand-Alone Solar PV System
Authors: Uloom N A , Mansur T M N T , Ali R , Baharudin N H , Abdullah A M
Published: August 2022

The standalone solar power system has long been used to meet the electrical needs of basic building structures. To counter the natural supply–demand imbalance caused by solar energy, standalone solar PV system often include energy storage devices, primarily lead–acid batteries. Due to lead-acid battery limitations, solar systems often have higher operational costs compared to traditional power systems. It has been discovered that a supercapacitor-battery hybrid energy storage device can be used to prolong the cycle life of a battery system by reducing the charge–discharge stress caused by variable power exchange. This research examines the influence of a supercapacitor on a photovoltaic system that makes use of a hybrid energy storage system that includes both batteries and supercapacitors in order to lessen the stress placed on the batteries. The methodology involves data collection for load profile and meteorological information, designing solar PV system, and simulation using Matlab SIMULINK to study the effect of supercapacitor on battery current of the evaluated system. Three different energy storage system topologies in building applications were simulated, and their ability in managing battery stress was investigated and evaluated. From the result, it is clear that by applying passive HES system, 53% of battery current can be reduced compared to battery-only system and 92% of reduction can be achieved by using semi-active HES system.
Electronic Ballast using Half Bridge Resonant Converter
Authors: Sukhi Y , Jeyashree Y , Jenifer A , Anita S , Ahamed A Fayaz
Published: August 2022

This paper presents a front-end ac-dc high power factor single stage topology. The proposed topology has good efficiency, better power factor and small size structure. The electronic ballast is designed with buck boost converter. The electronic ballast supplies power to fluorescent lamp. The lamp power regulation for the variations in the input voltage is assured. The steady state operation of the electronic ballast is done. The design of the converter in carried out from the basic principle. The equations for the electronic ballast circuit is derived from the basic principle and the analysis of the converter is done based on the equations. The elements used in the converter circuit is designed using the derived equations. The proposed converter circuit is developed for testing using 40W lamp and to determine the performance of the converter. The input pf measured has become more than 0.99. The electronic ballast efficiency with PFC circuit and buck boost converter is 94.46%
Feasibility study on the conversion of a small engine into a single-piston expander operating under different pressure and valve timing conditions
Authors: Mohamad M N A , Salim W S I W , Muhammad W N A W
Published: August 2022

There are limited studies on improving the piston expander performance for a wider operating range by adopting the variable valve timing method. This study uses a simple conversion technique to develop a single-piston expander (SPE) from a small two-stroke engine. The SPE is being tested at different operating conditions to study the feasibility of the SPE operating under different intake pressure and valve timing conditions. By fixing the exhaust valve timing, the SPE was tested at four intake pressure; 3, 4, 5, and 6 bar, while the intake valve closing varied from 30° to 110°. From the study, the highest power produced by the SPE was only 64 Watt when tested at 6 bar, with the intake valve opening at TDC and closed at 70°. The results show that the converted SPE is feasible in terms of functionality, but it is not performance-wise because much power has been lost through the recompression process. The study also observed that the intake valve timing could significantly affect the SPE power output, besides the intake pressure alone.
Fusion of Thermal and Depth Image to Improve Human Segmentation for a Mobile Robot
Authors: Hadi H S , Rosbi M , Sheikh U U
Published: August 2022

In machine vision, surveillance systems are a kind of security that concentrates on the safety of the human and property. One of the main tasks of a surveillance system is the detection of humans. This paper presents a system of human detection and the development of a technique of human segmentation using a combination of information thermal and depth in a real indoor setting from a mobile robot. A novel fusion of thermal-depth information (FTDI) is introduced to enhance the efficiency of the segmentation process and expedite processing. In experimental studies, evaluation of the performance for the proposed system is carried out using Ground Truth (GT), in which the proposed system yield is compared to GT. The proposed system performs well with an approximate accuracy of over 90% for all data sets as illustrated in the quantitative results and even outperformed state-of-the-art algorithms. This paper presents the novelty of the work, in which the detection method can improve the classification of persons and their occlusion. The advantages, such as being computationally inexpensive and performs well even under severe occlusion and poor illumination, show that this proposed system is robust.
Image reconstruction by shapefree radial basis function neural networks (RBFNs)
Authors: Paewpolsong P , Sriapai N , Tavaen S , Kaennakham S
Published: August 2022

With the growth of artificial intelligence technologies, the research on artificial neural networks (ANNs) has been paid much more attention. Radial basis function neural networks (RBFNs) are a type of ANNs that are referred to as models that replicate the role of biological neural networks. While their applications are growing in a wide range of areas, conventional forms of RBFs contain a highly problem-dependent shape parameter, making it not as convenient as one would expect. This work investigates the numerical effectiveness of RBFs containing no shapes, so they are referred to as ‘shapefree’, under the application of image reconstruction. Nine forms of shapefree RBFs have been gathered and implemented in conjunction with the RBFNs. Two popular images (known as Lena and Plane) are damaged in Salt-and-Pepper manner before being repaired by the networks using these shapefree RBFs. The overall performances are monitored based on error norm, CPU-time and storage, and condition number. This aims to provide useful information regarding choices of RBFs for future uses, to overcome the pain one faces from choosing a suitable value of shape parameter.
Carbon nanotubes’ amount and type: crucial parameters in mechanical performance enhancement on cement paste nanocomposites
Authors: Maria Falara , Athanasia Thomoglou , Fani Gkountakou , Anaxagoras Elenas
Published: August 2022

Single-wall (SWCNTs) and multi-wall (MWCNTs) carbon nanotubes’ affection on mechanical properties of cement-based nanocomposites is investigated in the present research. Three different amounts of CNTs, namely 0.05 %, 0.1 %, and 0.5 wt.% by weigth of cement were incorporated in nanomodified cementitious specimens. Flexural and compressive strength were determined for both types. The results reveal that MWCNT nanocomposites exhibit an improved mechanical performance for both flexure and compression as a function of the concentration up to 0.1 wt.% of the cement in contrast to SWCNT modified cementitious composites where the CNT addition leads either to a slight increase or a decrease. Results clearly reveal that the different type of reinforcement at the nanoscale beneficially alters the structure of the cement paste and enables the material to perform multiple structural functions. This investigation is expected to contribute significantly to create a cement based materials with improved mechanical performance.
Slice-to-voxel reconstruction of porous media using style-based generative adversarial networks
Authors: Huang Yubo , Xiang Zhong
Published: August 2022

Prediction of microstructure properties is of great significance for porous media, and the use of limited two-dimensional data to synthesize three-dimensional (3D) structural samples is an important support for this task. Although generative adversarial network technology has been successfully migrated to this scenario, its applicability is limited by the development of deep network technology. In this work, we use a more advanced StyleGAN architecture to accomplish this task and show that this method can achieve or even exceed the reconstruction effect of the previous voxel-to-voxel method.
Crack failure analysis of a temperature transmitter sleeving of a gas transmission station
Authors: Zhang Hongbo , Ren Guoqi , Wang Gaofeng , Yang Fengping
Published: August 2022

Based on the exterior morphology, fracture morphology and metallographic analysis and energy dispersive spectroscopy analysis, the causes of cracking of a temperature transmitter sleeving tube of a gas station are analyzed, the results showing that the main cause of the sleeving crack was the raw material of sleeving has not been treated with solid solution annealing or the heat treatment was not completely processed. therefore, the lack of treatment makes the material gathered a large number of Cr carbides on grain boundary, this leaded to the low anti intergranular corrosion ability; The thread in the sleeving does not meet the requirements of thread processing specifications, which caused the thread near the port to be squeezed in the service process of the sleeving, resulting in large tensile stress at the outer port of the sleeving. In the case of stress concentration caused by mechanical damage at the port position and the corrosion environment, stress corrosion cracking occurred at the port mechanical damage position and eventually lead to leakage.
Pretreatment method for BX24 Decon water of HD, VX and GD before GC analysis
Authors: Xu Mengxue , Wang Lianyuan , Zhu Haiyan , Zhang Hongpeng , Ge Liang
Published: August 2022

Chlorine-based decontaminant BX24 is effective for the decontamination of chemical warfare agents (CWAs) VX, GD and HD. In this paper, main factors affecting the agent recovery from decontamination water (decon water) were studied, a pretreatment method was subsequently developed for GC analysis of residual chemical warfare agents in BX24 decon water. Results showed that dichloromethane was the most suitable extractant, especially for sample of VX and GD. Neutralization process should be done to obtain a high recovery, especially for samples under low CWAs concentration and samples with high speed of CWAs degradation like HD decon water. When optimized neutralizer of sodium sulfite or sodium thiosulfate and extractant of dichloromethane were used, where neutralization and extraction were done simultaneously, a recovery above 85% could be obtained for BX24 decon water. The appropriate CWAs concentration ranged from 20 mg/l to 10000 mg/l.
Study on Thermo-oxidative Aging Mechanism of Air Spring Rubber Cord Composites
Authors: Guo Xiaohui , Yuan Xiaojing
Published: August 2022

To study the thermo-oxidative aging mechanism of air spring rubber cord composites, observe the changes in surface micro-morphology, study the thermo-oxidative aging mechanism of air spring rubber cord composites, observe the changes in surface micro-morphology, infrared spectrum, quality, hardness, and mechanical properties during the process of thermo-oxidative aging, and analyze the aging mechanism. The results show that the micro-morphological changes of the rubber surface of the rubber cord composites go through two stages: at 0-72 h, the rubber surface The results show that the micro-morphological changes of the rubber surface of the rubber cord composites go through two stages: at 0-72 h, the rubber surface develops from no cracks to a large number of cracks; at 96-336 h, the rubber surface changes from a cracked state. The size of the crack on the rubber surface affects the rate of change of IRHD hardness. The larger the crack, the greater the hardness growth rate, otherwise the opposite. In the aging process, the rubber is in a state of dynamic development. The increase of cross-linking density causes changes in microscopic The increase of cross-linking density causes changes in microscopic morphology and accessible volume, which affects the IRHD hardness. The aging mechanism is more complicated. Material failure is dominated by the failure of the rubber matrix.
Research on the Fluorescence Properties of Protoporphyrin-Modified Amphiphilic Polysilane
Authors: Pu Wenjing , Li Yue , Han Jiajia , Wang Shenhao , Lu Wei
Published: August 2022

Polysilanes are polymers with unique luminescent properties, which will be enhanced by functional side group modifications. In this paper, amphiphilic functional polysilane is synthesized by Si-H addition reaction between Si-H and alkene bonds. Polymethylsilane is selected as matrix which is full of reactive Si-H groups and azobisisobutyronitrile is used as the initiator. The product shows good luminescence (emission band between 400-650 nm), good solubility (soluble in various solvents such as toluene, tetrahydrofuran, n-hexane, dimethyl sulfoxide, alcohol and water) and environmental friendliness, which can be applied to flexible luminescent devices and solvent-based fluorescence detection in the future.
Preparation and Mechanical Properties of Thermal Insulation Silicone Rubber Composites
Authors: Pan Hongwei , Zang Chongguang , Chen Yijun
Published: August 2022

In this paper, three different functional phases of thermal insulation, hollow ceramic microspheres (HCM), hollow silica microspheres (HSM) and hydroxy silicone oil blowing agent (OH-3#)were selected, and a flexible and efficient thermal insulation composite with low thermal conductivity and high thermal structural strength was designed and prepared using the synergistic effect between the three. The results show that the thermal stability and mechanical performance of composites were significantly enforced.
Self-healing of structured light: a review
Authors: Shen Yijie , Pidishety Shankar , Nape Isaac , Dudley Angela
Published: August 2022

Self-healing of light refers to the ability of a light field to recover its structure after being damaged by a partial obstruction placed in its propagation path. Here, we will give a comprehensive review of the history and development of self-healing effects, especially highlighting its importance in vector vortex beams carrying spin and orbital angular momenta. Moreover, an unified zoology of self-healing, structured light is proposed to unveil a deeper understanding of its physical mechanism and provide a bird’s eye view on diverse forms of self-healing effects of different kinds of complex structured light. Finally, we outline the open challenges we are facing, potential opportunities and future trends for both fundamental physics and applications.
Quantitative evaluation of biaxial compressive strain and its impact on proton conduction and diffusion in yttrium-doped barium zirconate epitaxial thin films
Authors: Hyodo Junji , Yamazaki Yoshihiro
Published: August 2022

Proton-conducting oxides, including 20 mol% yttrium-doped BaZrO3 (BZY20), have attracted considerable attention as electrolytes for environmentally friendly electrochemical cells, such as proton ceramic fuel cells (PCFCs) and proton-conducting solid oxide cells. These oxides exhibit fast proton conduction due to the complex physicochemical phenomena of hydration, chemical lattice expansion, proton migration, proton trapping, and local distortion. Using a proton-conducting oxide as an electrolyte film in electrochemical devices introduces an interface, which thermally and chemically generates mechanical strain. Here, we briefly review the current state of research into proton-conducting oxides in bulk samples and films used in electrochemical devices. We fabricated 18 and 500 nm thick 20 mol% BZY20 epitaxial films on (001) Nb-doped SrTiO3 single-crystal substrates to form a model interface between proton-conductive and non-proton-conductive materials, using pulsed laser deposition, and quantified the mechanical strain, proton concentration, proton conductivity, and diffusivity using thin-film x-ray diffractometry, thermogravimetry, secondary ion mass spectrometry, and AC impedance spectroscopy. Compressive strains of −2.1% and −0.85% were measured for the 18 and 500 nm thick films, respectively, and these strains reduced both the proton conduction and diffusion by five and one orders of magnitude, respectively, at 375 °C. Analysis based on a simple trapping model revealed that the decrease in proton conduction results from the slower diffusion of mobile protons with a negligible change in the proton trapping contribution. The model shows that the high ohmic resistance reported for a high-performance PCFC with a power density of 740 mW cm−2 at 600 °C can be solely explained by the estimated compressive strain in the cells. This study shows that minimizing biaxial compressive strain by appropriate choices of the electrolyte–electrode combination and fabrication process is important for maximizing the performance of electrochemical cells.
Superconducting routing platform for large-scale integration of quantum technologies
Authors: Thomas C , Michel J-P , Deschaseaux E , Charbonnier J , Souil R , Vermande E , Campo A , Farjot T , Rodriguez G , Romano G , Gustavo F , Jadot B , Thiney V , Thonnart Y , Billiot G , Meunier T , Vinet M
Published: August 2022

To reach large-scale quantum computing, three-dimensional integration of scalable qubit arrays and their control electronics in multi-chip assemblies is promising. Within these assemblies, the use of superconducting interconnections, as routing layers, offers interesting perspectives in terms of (1) thermal management to protect the qubits from control electronics self-heating, (2) passive device performance with significant increase of quality factors and (3) density rise of low and high frequency signals thanks to minimal dispersion. We report on the fabrication, using 200 mm silicon wafer technologies, of a multi-layer routing platform designed for the hybridization of spin qubit and control electronics chips. A routing level couples the qubits and the control circuits through one layer of Al0.995Cu0.005 and superconducting layers of TiN, Nb or NbN, connected between them by W-based vias. Wafer-level parametric tests at 300 K validate the yield of these technologies while low temperature electrical measurements in cryostat are used to extract the superconducting properties of the routing layers. Preliminary low temperature radio-frequency characterizations of superconducting passive elements, embedded in these routing levels, are presented.
General spiking neural network framework for the learning trajectory from a noisy mmWave radar
Authors: Liu Xin , Yan Mingyu , Deng Lei , Wu Yujie , Han De , Li Guoqi , Ye Xiaochun , Fan Dongrui
Published: August 2022

Emerging usages for millimeter wave (mmWave) radar have drawn extensive attention and inspired the exploration of learning mmWave radar data. To be effective, instead of using conventional approaches, recent works have employed modern neural network models to process mmWave radar data. However, due to some inevitable obstacles, e.g., noise and sparsity issues in data, the existing approaches are generally customized for specific scenarios. In this paper, we propose a general neuromorphic framework, termed mm-SNN, to process mmWave radar data with spiking neural networks (SNNs), leveraging the intrinsic advantages of SNNs in processing noisy and sparse data. Specifically, we first present the overall design of mm-SNN, which is adaptive and easily expanded for multi-sensor systems. Second, we introduce general and straightforward attention-based improvements into the mm-SNN to enhance the data representation, helping promote performance. Moreover, we conduct explorative experiments to certify the robustness and effectiveness of the mm-SNN. To the best of our knowledge, mm-SNN is the first SNN-based framework that processes mmWave radar data without using extra modules to alleviate the noise and sparsity issues, and at the same time, achieve considerable performance in the task of trajectory estimation.
A review of non-cognitive applications for neuromorphic computing
Authors: Aimone James B , Date Prasanna , Fonseca-Guerra Gabriel A , Hamilton Kathleen E , Henke Kyle , Kay Bill , Kenyon Garrett T , Kulkarni Shruti R , Mniszewski Susan M , Parsa Maryam , Risbud Sumedh R , Schuman Catherine D , Severa William , Smith J Darby
Published: August 2022

Though neuromorphic computers have typically targeted applications in machine learning and neuroscience (‘cognitive’ applications), they have many computational characteristics that are attractive for a wide variety of computational problems. In this work, we review the current state-of-the-art for non-cognitive applications on neuromorphic computers, including simple computational kernels for composition, graph algorithms, constrained optimization, and signal processing. We discuss the advantages of using neuromorphic computers for these different applications, as well as the challenges that still remain. The ultimate goal of this work is to bring awareness to this class of problems for neuromorphic systems to the broader community, particularly to encourage further work in this area and to make sure that these applications are considered in the design of future neuromorphic systems.
AdipoQ—a simple, open-source software to quantify adipocyte morphology and function in tissues and in vitro
Authors: Sieckmann Katharina , Winnerling Nora , Huebecker Mylene , Leyendecker Philipp , Juliana Silva Ribeiro Dalila , Gnad Thorsten , Pfeifer Alexander , Wachten Dagmar , Hansen Jan N.
Published: August 2022

AdipoQ, an open-source software implemented as ImageJ plugins, allows us to analyze adipocytes in tissue sections and in vitro after histological and/or immunofluorescent labeling. AdipoQ implements batch processing of large datasets, provides a broad band of parameters, and allows combining multiple fluorescent readouts.
Mechanism of commitment to a mating partner in Saccharomyces cerevisiae
Authors: Jacobs Katherine C. , Gorman Olivia , Lew Daniel J.
Published: August 2022

In mating in yeast, cells use mobile polarity sites to explore the cortex until they come into alignment with a partner, at which point the polarity site stops moving and the cells “commit” to each other. The outstanding question of how the cells know when they have reached alignment is addressed.
Comparative studies of AlphaFold, RoseTTAFold and Modeller: a case study involving the use of G-protein-coupled receptors
Authors: Lee Chien , Su Bo-Han , Tseng Yufeng Jane
Published: August 2022

Neural network (NN)-based protein modeling methods have improved significantly in recent years. Although the overall accuracy of the two non-homology-based modeling methods, AlphaFold and RoseTTAFold, is outstanding, their performance for specific protein families has remained unexamined. G-protein-coupled receptor (GPCR) proteins are particularly interesting since they are involved in numerous pathways. This work directly compares the performance of these novel deep learning-based protein modeling methods for GPCRs with the most widely used template-based software—Modeller. We collected the experimentally determined structures of 73 GPCRs from the Protein Data Bank. The official AlphaFold repository and RoseTTAFold web service were used with default settings to predict five structures of each protein sequence. The predicted models were then aligned with the experimentally solved structures and evaluated by the root-mean-square deviation (RMSD) metric. If only looking at each program’s top-scored structure, Modeller had the smallest average modeling RMSD of 2.17 Å, which is better than AlphaFold’s 5.53 Å and RoseTTAFold’s 6.28 Å, probably since Modeller already included many known structures as templates. However, the NN-based methods (AlphaFold and RoseTTAFold) outperformed Modeller in 21 and 15 out of the 73 cases with the top-scored model, respectively, where no good templates were available for Modeller. The larger RMSD values generated by the NN-based methods were primarily due to the differences in loop prediction compared to the crystal structures.
R5hmCFDV: computational identification of RNA 5-hydroxymethylcytosine based on deep feature fusion and deep voting
Authors: Shi Hongyan , Zhang Shengli , Li Xinjie
Published: August 2022

RNA 5-hydroxymethylcytosine (5hmC) is a kind of RNA modification, which is related to the life activities of many organisms. Studying its distribution is very important to reveal its biological function. Previously, high-throughput sequencing was used to identify 5hmC, but it is expensive and inefficient. Therefore, machine learning is used to identify 5hmC sites. Here, we design a model called R5hmCFDV, which is mainly divided into feature representation, feature fusion and classification. (i) Pseudo dinucleotide composition, dinucleotide binary profile and frequency, natural vector and physicochemical property are used to extract features from four aspects: nucleotide composition, coding, natural language and physical and chemical properties. (ii) To strengthen the relevance of features, we construct a novel feature fusion method. Firstly, the attention mechanism is employed to process four single features, stitch them together and feed them to the convolution layer. After that, the output data are processed by BiGRU and BiLSTM, respectively. Finally, the features of these two parts are fused by the multiply function. (iii) We design the deep voting algorithm for classification by imitating the soft voting mechanism in the Python package. The base classifiers contain deep neural network (DNN), convolutional neural network (CNN) and improved gated recurrent unit (GRU). And then using the principle of soft voting, the corresponding weights are assigned to the predicted probabilities of the three classifiers. The predicted probability values are multiplied by the corresponding weights and then summed to obtain the final prediction results. We use 10-fold cross-validation to evaluate the model, and the evaluation indicators are significantly improved. The prediction accuracy of the two datasets is as high as 95.41% and 93.50%, respectively. It demonstrates the stronger competitiveness and generalization performance of our model. In addition, all datasets and source codes can be found at https://github.com/HongyanShi026/R5hmCFDV.
Advanced bioengineering of female germ cells to preserve fertility
Authors: Ghorbani Sadegh , Eyni Hossein , Norahan Mohammad Hadi , Zarrintaj Payam , Urban Nadine , Mohammadzadeh Alireza , Mostafavi Ebrahim , Sutherland Duncan S
Published: August 2022

Oogenesis and folliculogenesis are considered as complex and species-specific cellular differentiation processes, which depend on the in vivo ovarian follicular environment and endocrine cues. Considerable efforts have been devoted to driving the differentiation of female primordial germ cells toward mature oocytes outside of the body. The recent experimental attempts have laid stress on offering a suitable microenvironment to assist the in vitro folliculogenesis and oogenesis. Despite developing a variety of bioengineering techniques and generating functional mature gametes through in vitro oogenesis in earlier studies, we still lack knowledge of appropriate microenvironment conditions for building biomimetic culture systems for female fertility preservation. Therefore, this review paper can provide a source for a large body of scientists developing cutting-edge in vitro culture systems for female germ cells or setting up the next generation of reproductive medicine as feasible options for female infertility treatment. The focal point of this review outlines advanced bioengineering technologies such as 3D biofabricated hydrogels/scaffolds and microfluidic systems utilized with female germlines for fertility preservation through in vitro folliculogenesis and oogenesis.
Optimal row-column designs
Authors: Zhou Zheng , Zhou Yongdao
Published: August 2022

Row-column designs have been widely used in experiments involving double confounding. Among them, one that provides unconfounded estimation of all main effects and as many two-factor interactions as possible is preferred, and is called optimal. Most current work focuses on the construction of two-level row-column designs, while the corresponding optimality theory has been largely ignored. Moreover, most constructed designs contain at least one replicate of a full factorial design, which is not flexible as the number of factors increases. In this study, a theoretical framework is built up to evaluate the optimality of row-column designs with prime level. A method for constructing optimal row-column designs with prime level is proposed. Subsequently, optimal full factorial three-level row-column designs are constructed for any parameter combination. Optimal fractional factorial two-level and three-level row-column designs are also constructed for cost saving.
Phylogeography of the desert scorpion illuminates a route out of Central Asia
Authors: Shi Cheng-Min , Zhang Xue-Shu , Liu Lin , Ji Ya-Jie , Zhang De-Xing
Published: August 2022

A comprehensive understanding of phylogeography requires the integration of knowledge across different organisms, ecosystems, and geographic regions. However, a critical knowledge gap exists in the arid biota of the vast Asian drylands. To narrow this gap, here we test an “out-of-Central Asia” hypothesis for the desert scorpion Mesobuthus mongolicus by combining Bayesian phylogeographic reconstruction and ecological niche modeling. Phylogenetic analyses of one mitochondrial and three nuclear loci and molecular dating revealed that M. mongolicus represents a coherent lineage that diverged from its most closely related lineage in Central Asia about 1.36 Ma and underwent radiation ever since. Bayesian phylogeographic reconstruction indicated that the ancestral population dispersed from Central Asia gradually eastward to the Gobi region via the Junggar Basin, suggesting that the Junggar Basin has severed as a corridor for Quaternary faunal exchange between Central Asia and East Asia. Two major dispersal events occurred probably during interglacial periods (around 0.8 and 0.4 Ma, respectively) when climatic conditions were analogous to present-day status, under which the scorpion achieved its maximum distributional range. M. mongolicus underwent demographic expansion during the Last Glacial Maximum, although the predicted distributional areas were smaller than those at present and during the Last Interglacial. Development of desert ecosystems in northwest China incurred by intensified aridification might have opened up empty habitats that sustained population expansion. Our results extend the spatiotemporal dimensions of trans-Eurasia faunal exchange and suggest that species’ adaptation is an important determinant of their phylogeographic and demographic responses to climate changes.
Concurrent cardiac and central nervous system complications of acute infective endocarditis: case report
Authors: Prandi Francesca Romana , Anastasius Malcolm O , Matsoukas Stavros , Zhang Lily , Scaggiante Jacopo , Fifi Johanna T , Romeo Francesco , Lerakis Stamatios
Published: August 2022

Background

Cerebral mycotic aneurysms represent a rare but life-threatening complication of infective endocarditis (IE), with high mortality rate when ruptured. Due to the lack of randomized controlled trials, management of infectious aneurysms complicating endocarditis remains a controversial topic.

Case summary

We describe a case of Streptococcus salivarius bicuspid aortic and mitral valve endocarditis with concurrent spontaneous mycotic aneurysm rupture and acute subarachnoid haemorrhage (SAH). A 40-year-old man with history of intravenous drug abuse presented to our emergency department with altered mental status and dyspnoea. Echocardiography documented large vegetations on a bicuspid aortic valve and on the mitral valve, causing acute severe aortic and mitral regurgitation. Brain computed tomography imaging documented a ruptured fusiform aneurysm in a distal branch of the right middle cerebral artery causing acute SAH and acute obstructive hydrocephalus. An external ventricular drain was emergently placed and endovascular embolization of the aneurysm was achieved with deployment of six coils. Blood cultures grew S. salivarius and antibiotic therapy according to microbiological sensitivities was administered. Hospital stay was complicated by acute heart failure, ST-elevation myocardial infarction, conduction disturbances, cerebral vasospasm, recurrent mycotic aneurysm rupture, and death.

Discussion

Clinicians should be mindful of the rare, potentially severe complication of IE with cerebral mycotic aneurysms to enable prompt treatment. Generally, central nervous system procedures are performed prior to cardiac surgical management of IE, since cardiopulmonary bypass may exacerbate cerebral haemorrhage, ischaemic damage, and oedema in areas of blood–brain barrier disruption. A multidisciplinary collaboration is crucial for optimal patient management.
Understanding the digital impact of World Hypertension Day: key takeaways
Authors: Malhotra Kashish , Kalra Ankur , Kumar Ashish , Majmundar Monil , Wander Gurpreet Singh , Bawa Ashvind
Published: August 2022

Aim

To understand the global digital impact of World Hypertension Day and identify areas for further improvement to steer future policy development.

Methods and results

We used three social media assessment tools (Sprout Social, SocioViz, and Symplur) and Google Trends to obtain data about the total tweets and global impressions from countries worldwide about World Hypertension Day. Social network analysis of top influencers, associated hashtags, and keywords was performed to understand the context of the posts. With over 60 000 tweets reaching more than 250 million impressions, World Hypertension Day was a highly impactful event. A large spike of over 800% yearly increase was seen in 2021 that has greatly facilitated wider dissemination. However, there was limited collaboration among the top influencers and negligible participation from several African and non-English-speaking European countries.

Conclusion

With support from several governmental bodies, organizations and media outlets, World Hypertension Day is a highly impactful healthcare awareness day and presents a global case study of effectively utilizing digital resources for creating awareness among the global audience. Prioritizing equitable involvement from underrepresented and underprivileged communities must be focused. Future policy development of other awareness events shall extract the constructive feedback from these findings to promote global and public health.
Modified slide tracheoplasty technique in the management of a long-segment tracheoesophageal fistula
Authors: Duan Liang , Li Qiuyuan , Dai Jie , Jiang Gening
Published: August 2022

Post-tracheotomy tracheoesophageal fistula remains a challenge because it frequently involves a considerable length of the trachea. We report a case in which a modified slide tracheoplasty was successfully used to repair a long-segment, subglottic post-tracheotomy tracheoesophageal fistula. This technique not only shortened the length of the resected tracheal segment but also maintained the patency of the tracheal lumen.