bluuebunny/crossref_metadata_2025_split huggingface dataset:
A CT image feature space (CTIS) loss for restoration with deep learning-based methods
Authors: Zheng Ao , Liang Kaichao , Zhang Li , Xing Yuxiang 
Published: February 2022

Abstract

Objective. Deep learning-based methods have been widely used in medical imaging field such as detection, segmentation and image restoration. For supervised learning methods in CT image restoration, different loss functions will lead to different image qualities which may affect clinical diagnosis. In this paper, to compare commonly used loss functions and give a better alternative, we studied a widely generalizable framework for loss functions which are defined in the feature space extracted by neural networks. Approach. For the purpose of incorporating prior knowledge, a CT image feature space (CTIS) loss was proposed, which learned the feature space from high quality CT images by an autoencoder. In the absence of high-quality CT images, an alternate loss function, random-weight (RaW) loss in the feature space of images (LoFS) was proposed. For RaW-LoFS, the feature space is defined by neural networks with random weights. Main results. In experimental studies, we used post reconstruction deep learning-based methods in the 2016 AAPM low dose CT grand challenge. Compared with perceptual loss that is widely used, our loss functions performed better both quantitatively and qualitatively. In addition, three senior radiologists were invited for subjective assessments between CTIS loss and RaW-LoFS. According to their judgements, the results of CTIS loss achieved better visual quality. Furtherly, by analyzing each channel of CTIS loss, we also proposed partially constrained CTIS loss. Significance. Our loss functions achieved favorable image quality. This framework can be easily adapted to other tasks and fields.
Fine-grained calibrated double-attention convolutional network for left ventricular segmentation
Authors: Lu Chenggang , Guo Zhitao , Yuan Jinli , Xia Kewen , Yu Hengyong 
Published: February 2022

Abstract

Objective. Left ventricular (LV) segmentation of cardiac magnetic resonance imaging (MRI) is essential for diagnosing and treating the early stage of heart diseases. In convolutional neural networks, the target information of the LV in feature maps may be lost with convolution and max-pooling, particularly at the end of systolic. Fine segmentation of ventricular contour is still a challenge, and it may cause problems with inaccurate calculation of clinical parameters (e.g. ventricular volume). In order to improve the similarity of the neural network output and the target segmentation region, in this paper, a fine-grained calibrated double-attention convolutional network (FCDA-Net) is proposed to finely segment the endocardium and epicardium from ventricular MRI. Approach. FCDA-Net takes the U-net as the backbone network, and the encoder-decoder structure incorporates a double grouped-attention module that is constructed by a fine calibration spatial attention module (fcSAM) and a fine calibration channel attention module (fcCAM). The double grouped-attention mechanism enhances the expression of information in both spatial and channelwise feature maps to achieve fine calibration. Main Results. The proposed approach is evaluated on the public MICCAI 2009 challenge dataset, and ablation experiments are conducted to demonstrate the effect of each grouped-attention module. Compared with other advanced segmentation methods, FCDA-Net can obtain better LV segmentation performance. Significance. The LV segmentation results of MRI can be used to perform more accurate quantitative analysis of many essential clinical parameters and it can play an important role in image-guided clinical surgery.
Abnormal trend in hot carrier degradation with fin profile in short channel FinFET devices at 14 nm node
Authors: Kuo Ting-Tzu , Chen Ying-Chung , Chang Ting-Chang , Chang Kai-Chun , Yeh Chien-Hung , Ciou Fong-Min , Lin Yu-Shan , Lin Yun-Hsuan , Jin Fu-Yuan , Hung Wei-Chun , Chang Yen-Cheng , Chen Kuan-Hsu , Lin Jia-Hong 
Published: February 2022

Abstract
This study investigates the impact of fin profiles under hot carrier stress, which defines different base widths: wide-base samples with the smallest slope, medium-base samples, and narrow-base samples with a larger slope. The performance of the narrow samples is better than the medium samples, regardless of transconductance, on-state current, subthreshold swing or drain-induced barrier lowering, demonstrating that the narrow profile samples’ mobility and gate control are better. In long channel devices, the trend of hot carrier degradation (HCD) is in agreement with previous references, and is dependent on the transverse electric field and the fin shapes. However, this trend does not exist for short-channel devices. Positive bias stress and technology computer aided design simulation are applied for investigation and to clarify the reasons for this abnormal HCD trend. Finally, by fitting the multiple vibrational excitation (MVE) mechanism, the slope of the trend lines in the short channel devices are found to indeed match the bending mode. In other words, the disappearance of the general trend between the HCD and fin profiles is caused by the change in the mechanism in the short-channel device. Because the MVE mechanism is independent from the electric field, the narrow profile fin shape more effectively promotes gate control and better performance without affecting the reliability in short channel devices. These results can provide a clear direction for fin shape designers in the future.
Thermal, mechanical and shape fixity behaviors of shape memory cyanate under γ-ray radiation
Authors: Wang Linlin , Zhang Fenghua , Liu Yanju , Du Shanyi , Leng Jinsong 
Published: February 2022

Abstract
Smart materials and structures have developed rapidly, especially their application in the aerospace field has been widely valued and recognized in recent years. Shape memory cyanate ester (SMCE) resin as a class of smart polymers has a broad application prospect in space deployable structure due to the high glass transition temperature (Tg
) and excellent mechanical properties. In this work, the SMCE resins were prepared by regulating cyanate prepolymer with small molecules, showing high Tg
(> 218 °C) and high storage modulus (E' > 3.15 GPa). The SMCE resins maintained a high shape fixity rate (Rf
> 95%) at high operating temperatures (100 °C and 120 °C) for 30 d, providing a great potential application for active deformation structures. Moreover, the synergy of carboxyl (–COOH) functionalized multi-walled carbon nanotubes and short carbon fiber enhanced the thermodynamic properties and shape-changing function of the SMCE composites. The spring made by SMCE composite exhibits 360° freedom rotation, which can be used as smart structures in the aerospace field.
First principle study of band gap tuning in Cs2InSbX6 (X = Cl, Br, I) for optoelectronic and thermoelectric applications
Authors: Aslam Fatima , Ullah Hamid , Hassan M 
Published: February 2022

Abstract
In this work, density-functional theory based theoretical investigations of novel and less studied double perovskites Cs2InSbX6 (X = Cl, Br, I) are performed to analyze the structural and electronic behaviors. The electronic structures computed using PBEsol are further subjected to Tran-Blaha modified Becke-Johnson (TB-mBJ) potential, and tuning of the semiconducting direct band gap is observed as 1.77 eV, 1.07 eV and 0.35 eV for Cs2InSbX6 (X = Cl, Br, I), respectively. The structural stability is confirmed from the computed tolerance factors and enthalpy of formation. Thermodynamic stability is also revealed by the computed phonon spectra. The halogen ions based band gap tuning in Cs2InSbX6 (X = Cl, Br, I) show systematic variation of the computed optical parameters against impinging energies. The thermoelectric properties are found consistent with various transport parameters. The narrow band gap Cs2InSbI6 (0.35 eV) results comparatively high power factor. The band gap tuning based variations in the optical and thermoelectric parameters have revealed potential applications in energy absorption and conversion devices, respectively.
Electron paramagnetic resonance study of silicon-28 single crystal for realization of the kilogram
Authors: Mizushima Shigeki , Umeda Takahide 
Published: February 2022

Abstract
To realize the kilogram with high accuracy using the x-ray crystal density method, mass deficit correction to account for the number of vacancy defects in silicon-28 crystals is necessary. In this paper, we present the results of electron paramagnetic resonance (EPR) spectroscopy experiments performed on a silicon-28 crystal. The crystal was cut from near the radial center of the Si28–23Pr11 crystal boule where a relatively high vacancy defect concentration was expected within the boule, which was grown by the floating zone method. We obtained both the in-phase and out-of-phase EPR spectra, which focused on the fast- and slow-spin relaxation centers, respectively. Based on EPR measurements both in the dark and under illumination, the concentrations of phosphorus impurities with unpaired electrons were found to be between 1.6 × 1012 cm−3 and 3.4 × 1012 cm−3. In contrast, EPR-active vacancy defects in the silicon-28 crystal were not detected at the detection sensitivity of the present measurements (around 1 × 1012 cm−3), although at the Si/SiO2 interface, dangling-bond defects (P
b0 centers) were detected with an areal density between 0.4 × 1012 cm−2 and 1.7 × 1012 cm−2. The experimental detection of a larger amount of phosphorus donors under illumination indicates the presence of compensation centers (electronic levels acting as acceptors) with a concentration of at most 1.6 × 1012 cm−3. We determined that such a concentration is mainly compensated by the boron acceptors, and that there is little contribution of electrically active vacancy defects, 0.0(6) × 1012 cm−3. This value is much smaller than the previously reported concentrations of 1 × 1014 cm−3 to 4 × 1014 cm−3 for vacancy defects determined by positron annihilation spectroscopy.
New synergy effects of the lower hybrid wave and the high harmonic fast wave current drive
Authors: Yin Lan , Zheng Pingwei , Gong Xueyu , Yang Cheng , Yin Xianghui , Song Chengyi , Huang Qianhong , Chen You , Zhong Yijun 
Published: February 2022

Abstract
The combined drive current of the lower hybrid wave (LHW) and the high harmonic fast wave (HHFW) was studied theoretically for the first time, based on the use of low and higher β
e operational parameters in EAST. Broad and significant synergistic effects are found in the simulation, the current drive (CD) efficiency is greatly improved, and the current profile is modified as a result of the synergy between the two types of waves. The LHW interacted with the resonant electrons in low parallel velocity region and pushes them into the adjacent resonance region of the high phase velocity wave (HHFW), thus the number of fast electrons resonant with the HHFW is increased dramatically, and the driven current is enhanced. Therefore the synergy effect strongly depends on the positional relation between the velocity resonance regions of the two waves. Moreover, the effects of the parallel refractive index, the wave frequency and the wave power on the synergy effect are examined. Some problems well known in the single LHW CD or the HHFW CD may be overcome by the combined CD.
An Improved Whale Optimization Algorithm for Robot Time-jerk Optimal Trajectory Planning
Authors: Zhao Jing , Zhu Xijing , Song Tianjiao , Meng Xiaoling 
Published: February 2022

Abstract
Optimal path planning in the welding process enhances the processing and manufacturing efficiency. An effective algorithm for optimum path planning of a six-axis welding industrial robot is established in this paper. The robot’s trajectory is constructed using 5-th B spline interpolation in the joint space, and a cost function is constructed in terms of both time and mean jerk. An improved whale optimization algorithm (IWOA) is presented to address the time-jerk optimal trajectory planning issue. The robot’s joint positions are considered the IWOA input, while the MATLAB 2018b software is utilized to perform the optimization algorithm. Numerical simulations demonstrate that IWOA can effectively reduce the jerk of the robot while improving its work efficiency.
Research on Self-Tracking Car Based on Fuzzy-PID Control Algorithm
Authors: Zhou Yukun 
Published: February 2022

Abstract
Aiming at the problem that the traditional PID control algorithm can not control the motor speed of intelligent self-tracking car facing the dynamic changes of the system, this paper proposes a control algorithm based on fuzzy control rules. And the comparison between the proposed Fuzzy-PID control algorithm and the traditional PID control algorithm is analyzed by using MATLAB simulation model. The simulation results show that Fuzzy-PID control algorithm not only retains the advantages of the traditional PID control algorithm is simple and needs small calculation, but also can adapt to the dynamic changes of the system to enhance the anti-interference performance and adaptive ability of the system, and has a faster response speed compared with the traditional PID algorithm.
Nonsingular fast terminal sliding mode control for manipulator based on combinatorial reaching law
Authors: Wang Binghui , Mi Gensuo 
Published: February 2022

Abstract
Aiming at the problems of external disturbance, modeling errors, tracking speed and chattering in manipulator trajectory tracking control, a nonsingular fast terminal sliding mode control strategy for manipulator based on combinatorial reaching law was proposed. First, the nonlinear disturbance observer was used to observe the system’s external disturbance and modeling errors. Then, on the basis of the nonsingular fast terminal sliding mode surface, an improved nonsingular fast terminal sliding mode surface was proposed, which improves the convergence speed in the sliding motion process of sliding mode control. At the same time, a combinatorial reaching law combining the power reaching law and the variable speed reaching law was proposed, which improved the approach speed of the system under the premise of weakening the chattering. The simulation results verified the effectiveness of this control strategy.
Matching and Planning of Machining Process Based on Similarity Principles
Authors: Zhao Ping , Gao Hongbo 
Published: February 2022

Abstract
In order to meet the requirements of intelligent and digital process planning, a similarity-based process planning method is studied. Firstly, the characteristics of part machining features and machining process are analyzed, and the representation and retrieval model of part feature cases is established; Secondly, the principle of process combination based on factory and parallel principle is put forward, and the clustering hierarchy method is used to combine the processes, and the process elements in the process family are sorted and combined to generate the part process. The feasibility of this method is verified by an example, which can realize the digital design of machining process for complex parts such as engine cylinder block and cylinder head, thereby realize high-precision flexible machining.
Deviated Direction of Arrival Method for Radial Velocity Measurement based on Spatial Spectrum Estimation
Authors: Mei Hui , Yi Kun , Song Ke , Zhu Weicai , Wang Chao , Li Qian 
Published: February 2022

Abstract
In this paper, a new scheme to measure radial velocity based on direction of arrival (DOA) estimation with multiple signal classification (MUSIC) algorithm is proposed. The MUSIC algorithm usual applications in Uniforms Linear Arrays (ULA) don’t enable velocity estimation because the array signals in one snapshot are synchronous and the radial motion does not affect the steering vector. In the proposed scheme, signal snapshot is rearranged so that each vector now contains a sequence of signals from adjacent elements delayed in time, this way the steering vector input to the MUSIC algorithm includes both information of the DOA and radial velocity. An equation describing the relationship of the deviated DOA (dDOA) from the rearranged snapshot with the radial velocity and the DOA is presented. For multi-source situation, pairing problem of DOAs and dDOAs is solved by extracting the combination factors of the steering vectors and the eigenvectors in comparison between the two MUSIC implementations. Comparison with the traditional FFT method shows that a higher accuracy of velocity can be achieved by the proposed method.
Performance Enhancement of Finned Tube Heat Exchanger using New Vortex Generator
Authors: Rai Shubhanshu , Singh Shobhana 
Published: February 2022

Abstract
The present work aims to investigate a performance enhancement in an H-shaped finned tube heat exchanger using a new design of winglet vortex generator. The new design has an aerodynamic shape that reduces the pressure drop and enhances the heat transfer, resulting into an improvement in the overall thermo-hydraulic performance. A three-dimensional model is developed using ANSYS fluent to carry out simulations for Reynolds number varying between 5000 ≤ Re ≤ 11000 and to predict the net enhancement in the heat exchanger performance. The validation of the model is done using experimentally developed correlations of dimensionless pressure drop and heat transfer characteristics. Comparative results for the finned tube heat exchanger with and without vortex generator are presented. Results indicate a significant enhancement in the heat transfer characteristics of the finned tube heat exchanger with the new design of vortex generator. Volume goodness ratio and Colburn j-factor found to be 19.63% and 30.33% higher than the baseline finned tube heat exchanger without any vortex generator.
Estimation of Shearing and Peeling Thermal Stress of Spinel Coated Metallic Interconnects of Solid Oxide Fuel Cells
Authors: Pavan Sai Dosawada , Singh Sikarwar Basant , Kumar Singh Rajeev 
Published: February 2022

AbstractInterconnects are used in solid oxide fuel cells (SOFCs) for connecting the fuel cell stacks. These interconnect are coated with spinel oxides to prevent the formation of a native scale oxide layer under high heat flux conditions. Generally, the SOFCs are subjected to thermal shock during their operation. At the interfaces of these coating, shear stresses and peeling stresses were induced due to a mismatch between the thermal expansion coefficient of coating and native scale thickness. These stresses peel off the coating layers which affect the interconnect performance. In this paper, the effect of varying native scale thickness at two different coating thicknesses on the shearing stress and peeling stress of the interconnects is analytically calculated along the two different interconnect thicknesses. The oxidation kinetics of spinel-coated SOFCs interconnects with the analytical equations relating native scale thickness with the time of SOFCs operation were reported. As per our analysis, we concluded that these stresses majorly depend on the thickness and the mechanical properties of the interconnects, native scale and a coating layer.
Computational study for the optimization of Ranque-Hilsch vortex tube with the variation of number of inlet chamber and distance between the chambers
Authors: Kant Singh Ravi , Kumar Pramanick Achintya , Chandra Rana Subhas 
Published: February 2022

Abstract
The purpose of the present study is to analyse the improvement in the performance of vortex tubes numerically. The air is taken as the working fluid in the compressible, axisymmetric 3-D, turbulent flow, and steady-state vortex tube. The standard k-ɛ turbulent model has been used for flow simulation in ANSYS FLUENT software with different pressure at the inlet and validated with experimental outcomes. It is found that there is an increment of 9.09 % in the cold temperature gradient with three inlet chambers as compared to single chamber. When inlet chamber numbers change from three to four, a decrease in the cold temperature gradient is recorded. When the distance between the inlet chamber increases from 8 mm to 32 mm, there is a decrease in the vortex tube’s cold temperature gradient. Therefore, it indicates that the optimum number of inlet chambers to obtain maximum cold temperature gradient, i.e., minimum cold exit temperature for the given specification of the vortex tube essential to have three inlet chambers, and the optimum distance between the inlet chambers 8 mm, is recommended.
Application of Hybrid Method Based On MRT-Lattice Boltzmann and Finite Difference to Study Heat Transfer in Three Dimensions
Authors: Benhamou J. , Lahmer E. B. , Jami M. , Moussaoui M. A. , Mezrhab A. , Phanden R. K. 
Published: February 2022

Abstract
The importance of studying the cooling of electronic components, which can be represented by obstacles, by natural or forced convection, has led our research laboratory to study this type of problem in 2D for many years. In this present article, the code is developed to be able to simulate heat transfers in 3D using a hybrid method. This approach is built on two numerical approaches viz the “Lattice Boltzmann method” (LBM) for the study of the fluid flow and the “Finite Difference Method” (FDM) for the calculation of the temperature field. The present numerical code is validated in the case of natural convection in a cubic cavity packed with air. Subsequently, the heat exchange between two cold vertical walls and a heated obstacle placed at center of cavity is studied.
Effect of anti-oxidant additive on oxidation stability of biodiesel
Authors: Yadav Khushbu , Bisht Anshul , Anwar Sohrab , Kharbanda Civarin 
Published: February 2022

Abstract
Due to growth in population and lifestyle, energy consumption is also rapidly increasing with our everyday life. The demand for petroleum products is constantly increasing ever since it has been discovered and being a non-renewable resource, we have it in limited quantities. We are in need to discover an alternate fuel that can be used to replace petroleum products. Considering this, the use of biodiesel can be one of the possible solutions for the future energy demand if the properties of biodiesel can be matched with that of petroleum products, as biodiesel is a renewable and bio-degradable fuel. The biodiesel has been prepared by using Sesame oil and its oxidation stability has been tested with the help of the rancimat test. It has been attempted to increase the oxidation stability of the biodiesel by the addition of antioxidant additives and the most common additives like TBHQ and PY have been used. The research compares the effect of Diphenylamine (DPA) as an antioxidant additive with the results of other additives. And it has been observed that all three of the additives have an almost similar effect on oxidation stability.
Investigation on corrosion characteristics of SS316L by thermal spray coating technique using Ni-80Cr alloy
Authors: Kumari Sinha Ragini , Nagpal Yatan , Sharma Rohit , Kumar Niraj 
Published: February 2022

AbstractIn the current study, an investigation was carried out to evaluate the corrosion characteristics of thermal spray coated SS316L with Ni-80Cr as a coating material developed by Detonation-Gun method. The corrosion behavior was investigated on uncoated SS, single layer coated SS316L and multilayer coated SS316L by conducting the corrosion test for 90 hours in stagnant seawater. Results showed that corrosion resistance of SS316L was found to be increased by single and multilayer coating of Ni-80Cr. The coating of Ni-80Cr alloy was found to enhance corrosion resistance.