bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seagrass meadows provide multiple benefits to adjacent coral reefs through various microhabitat functions
Authors: Du Jianguo , Hu Wenjia , Nagelkerken Ivan , Sangsawang Laddawan , Loh Kar Hoe , Ooi Jillian Lean-Sim , Liao Jianji , Zheng Xinqing , Qiu Shuting , Chen Bin 
Published: August 2020

ABSTRACT
Tropical seagrass meadows and coral reefs often function as interconnected marine habitats, but they are often studied and managed as homogenous units. As macrohabitats, seagrass meadows provide important benefits to adjacent reef ecosystems by acting as natural filters of sediments and nutrients, and by providing critical feeding, nursery, and refuge habitats for reef fishes and other fauna. Whilst the macrohabitat functions of seagrass meadows have been often acknowledged, their microhabitats functions have largely been neglected. The purpose of the study is to explore how seagrass meadows provide multiple benefits to adjacent coral reefs through various microhabitat functions. The paper reveals some of the diversity of microhabitats that seagrass meadows contain, such as macroalgal mats, rubble cavities, sand patches with sparse seagrass, anemone gardens, hard substratum, and sponges mixed with seagrass. We highlight the ways in which reef creatures have diversified and specialized in using these different microhabitats, and postulate that seagrass microhabitat diversity enhances the habitat function and faunal diversity of seagrass meadows.
High figure-of-merit in the heavy-fermion UN2 system for radioisotope thermoelectric applications
Authors: Zhou Z Z , Fan D D , Liu H J , Liu J 
Published: August 2020

Abstract
The design of uranium-based thermoelectric (TE) materials presents a novel and intriguing strategy for directly converting nuclear heat into electrical power. Using high-level first-principles approach combined with accurate solution of Boltzmann transport equation, we demonstrate that a giant n-type power factor of 13.8 mW m−1 K−2 and a peak ZT value of 2.2 can be realized in the heavy-fermion UN2 compound at 700 K. Such promising TE performance arises from the large degeneracy (N
v = 14) of heavy conduction band coupled with weak electron–phonon interactions, which is in principle governed by the strong Coulomb correlation among the partially filled U-5f electrons in the face-centered cubic structure. Collectively, our theoretical work suggests that the energetic UN2 could serve as both excellent heat source and efficient power convertor, which also uncovers an underexplored area for TE research.
High-performance x-ray source based on graphene oxide-coated Cu2S nanowires grown on copper film
Authors: Zhang Daoshu , Zhang Siyuan , He Ke , Wang Libin , Sui Fan , Hong Xuda , Li Weiwei , Li Nianci , Jia Meiling , Li Weimin , Wang Zhixun , Wang Zongpeng , Du Bi , Wei Lei , Feng Ye , Zhong Guohua , Li Wenjie , Chen Jun , Yang Chunlei , Chen Ming 
Published: August 2020

Abstract
Full static x-ray computed tomography (CT) technology has enabled higher precision and resolution imaging and has been applied in many applications such as diagnostic medical imaging, industrial inspection and security screening. In this technique, the x-ray source section is mainly composed of a thermionic cathode and electron beam scanning system. However, they have several shortcomings such as limited scanning angle, long response time and large volume. Distributed and programmable cold cathode (i.e. carbon nanotubes, ZnO nanowires (NWs)) field-emission x-ray sources are expected to solve these problems. However, there have been several long-standing challenges to the application of such cold field emitters for x-ray sources, such as the short lifetime and rigorous fabrication process, which have fundamentally prevented their widespread use. Here, we propose and demonstrate a cold field-emission x-ray source based on a graphene oxide (GO)-coated cuprous sulfide nanowire (Cu2S NW/GO) cathode. The proposed Cu2S NW/GO x-ray source provides stable emission (>18 h at a direct voltage of 2600 V) and has a low threshold (4.5 MV m−1 for obtaining a current density of 1 μA cm−2), benefiting from the demonstrated key features such as in situ epitaxy growth of Cu2S NWs on Cu, nanometer-scale sharp protrusions within GO and charge transfer between the Cu2S NWs and GO layer. Our research provides a simple and robust method to obtain a high-performance cold field emitter, leading to great potential for the next generation of x-ray source and CT.
Detective quantum efficiency of intensified CMOS cameras for Cherenkov imaging in radiotherapy
Authors: Alexander Daniel A , Bruza Petr , Farwell J Cedar M , Krishnaswamy Venkat , Zhang Rongxiao , Gladstone David J , Pogue Brian W 
Published: August 2020

Abstract
In this study the metric of detective quantum efficiency (DQE) was applied to Cherenkov imaging systems for the first time, and results were compared for different detector hardware, gain levels and with imaging processing for noise suppression. Intensified complementary metal oxide semiconductor cameras using different image intensifier designs (Gen3 and Gen2+) were used to image Cherenkov emission from a tissue phantom in order to measure the modulation transfer function (MTF) and noise power spectrum (NPS) of the systems. These parameters were used to calculate the DQE for varying acquisition settings and image processing steps. MTF curves indicated that the Gen3 system had superior contrast transfer and spatial resolution than the Gen2+ system, with

f

10

values of 0.52 mm−1 and 0.31 mm−1, respectively. With median filtering for noise suppression, these values decreased to 0.50 mm−1 and 0.26 mm−1. The maximum NPS values for the Gen3 and Gen2+ systems at high gain were 1.3 × 106 mm2 and 9.1 × 104 mm2 respectively, representing a 14x decrease in noise power for the Gen2+ system. Both systems exhibited increased NPS intensity with increasing gain, while median filtering lowered the NPS. The DQE of each system increased with increasing gain, and at the maximum gain levels the Gen3 system had a low-frequency DQE of 0.31%, while the Gen2+ system had a value of 1.44%. However, at a higher frequency of 0.4 mm−1, these values became 0.54% and 0.03%. Filtering improved DQE for the Gen3 system and reduced DQE for the Gen2+ system and had a mix of detrimental and beneficial qualitative effects by decreasing the spatial resolution and sharpness but also substantially lowering noise. This methodology for DQE measurement allowed for quantitative comparison between Cherenkov imaging cameras and improvements to their sensitivity, and yielded the first formal assessment of Cherenkov image formation efficiency.
Transient non-classical transport in the hollow cathode plume II: evaluation of models for the anomalous collision frequency
Authors: Georgin Marcel P , Jorns Benjamin A 
Published: August 2020

Abstract
The ability of fluid-based closure models to describe the non-classical electron collision frequency in the plume of a hollow cathode is experimentally investigated. Six models—all predicated on the assumption that the non-classical collision frequency can be attributed to ion acoustic turbulence (IAT)—are considered. Experimental measurements of the time-resolved plasma properties in the cathode plume (Georgin M P, Jorns B A and Gallimore A D 2020 PlasmaSources Sci. Technol, 29 105010) are used to evaluate each closure model and compare it to experimental measurements of the effective electron collision frequency. Though more than one of the considered closures can predict the time-average behavior of the plasma in the cathode plume, it is found that only one model accurately predicts the measurements in both space and time for the cathode and operating conditions that were studied. This new highest fidelity model is derived using a single-equation approach based on modeling the average frequency of the IAT as it evolves in space and time. The implications of the success of this model are discussed in the context of the understanding of the dynamics of the IAT in the cathode plume as well as on-going fluid-based modeling efforts related to cathode plumes.
Design and Implementation of CNC System for WEDM Machine Tool Based on Active Object
Authors: Yuanlong Chen , Zhuangzhuang Wang , Bolin Dong 
Published: August 2020

Abstract
A software framework design method for embedded real-time control system is proposed for the conversion of internal behavior state of CNC machine tool control system. This method uses the active object calculation model to plan and model the internal state of the linear cutting CNC system. On this basis, an open machine tool control system is built, and the design of the linear cutting machine bed control system is realized. The system design realizes the middle layer of the system based on a lightweight framework, and truly realizes the separation of the hardware and software of the control system. Each object is independent of each other and does not share resources. Information events are distributed through the “Publication-Subscription” method, and the line is designed to be cut. It can solve the problem of poor reconstruction ability of the original system and improve the portability of the system.
Influencing factors of self-rotating micro device based on water droplet
Authors: Guan Fusheng , Sun Jing 
Published: August 2020

Abstract
Self-propelling micro devices, which means moving spontaneously without traditional motor, have been widely studied in recent years. We proposed a new kind of self-rotating micro device based on water droplet, which can achieve rotating without any external energy. It can transform surface energy of the water droplet into kinetic energy of the micro device. And the feasibility experiment showed that the micro device work well, the numerical analysis of the micro device about the rotating velocity varied with the different center distance and number of the inclined pores provided us an empirical equation to predict the rotating property of the micro device, and an application model in micro generator field was proposed. The self-rotating micro device is a totally original self-propelling device with a green propelling mechanism to the environment.
Design and Research on the detection system of controllable distance measuring device
Authors: Gan Yong , Zhang Qiufeng , Luan Junkai , Jia Cuiyun 
Published: August 2020

Abstract
In view of the defects of the existing hand-held Multimeter in measurement, such as difficult to operate and low measurement accuracy, a new type of component measurement device based on controllable distance expansion is proposed, and its detection system is designed and studied based on the device. By using LabVIEW programming software as the development environment and calling DAQ assistant function to configure the relevant voltage and current parameters, the DAQ acquisition board module integrated in the measurement device realizes the interactive communication between the data, and realizes the voltage and current acquisition of the system control. The experimental results show that the system can detect the voltage, current or resistance of components quickly, and the system has strong readability and high data precision.
A new Construction Method of Vehicle Digital Camouflage Spraying Model
Authors: Zhang Qirong , Jin Xin , Liu Qi , Zou Yuchu 
Published: August 2020

Abstract
Digital camouflage plays an important role in improving the combat performance of vehicles. The reconstruction of the spraying model of the automobile surface can improve the automation level of the digital camouflage painting operation. The surface digital camouflage spraying model construction method is a processing flow that incorporates a variety of technical methods, including surface point cloud data collection technology, point cloud synthesis and segmentation method, surface model reconstruction method and spray pattern fusion technology. Four linear laser sensors are used to scan the vehicle surface to obtain the local point cloud data of the vehicle. The vehicle CAD model and the painting pattern figures are analysed. And the region growing segmentation method is used to subdivide the scanned point cloud data. For the point cloud after partitioning, the point set of the digital camouflage pattern is directly searched by using the constructed discrete metric. Then each point cloud is merged with the 2D camouflage pattern to obtain the digital camouflage spraying model of the vehicle surface.
Mechanical Influence Analysis and Experimental Study of 3D Printing Fault
Authors: Lianghua Zeng 
Published: August 2020

Abstract
The occurrence of faults in 3D printing is random. Faults in the printing have a great influence on printing quality, which may affect the surface quality, dimensional accuracy and mechanical properties of the printed part. Serious malfunctions can cause printing to fail, resulting in waste. In order to better understand the influence mechanism and extent of faults on printed parts, the paper conducts the analysis of generation mechanism and mechanical influence of two types of printing faults such as congealed tumor and overhang printing based on experiments. The paper also summarizes the mathematical expressions of the influence of printing fault, which aims to provide a reference for further fault monitoring, removing and compensating.
Design of High-lightweight Space Mirror Component Based on Automatic Optimization
Authors: Wu Jianfu 
Published: August 2020

Abstract
Aiming at the problems of high weight, low cost and extremely short development cycle faced by commercial aerospace space remote sensing cameras, a mathematical model with modal fundamental frequency as the objective function under the constraints of weight and size has been established. Through the automatic optimization method, the lightening rate of the mirror can reach 71.8%. Using the “2 + 2 + 2” quasi-static constraint as the criterion, the flexible support structure of the mirror is optimally designed to realize the high rigidity of the component and ensure the high bearing capacity of the force and thermal environment. Static simulation analysis of the design results of the mirror assembly using hypermesh shows that under the combined influence of gravity field and temperature field, the change of the mirror surface shape (RMS) is within 0.0056λ. At the same time, the modal analysis of the design results shows that the first-order natural frequency of the component can reach 146.52 Hz, which has extremely high dynamic stiffness. It can effectively adapt to the dynamic environment, and the design of the mirror assembly can fully meet the needs of commercial aerospace space remote sensing cameras.
Efficiency Evaluation of Air-defense Early-warning Detection Based on Communication Support
Authors: Zhou Zheshuai , Li Yuntao , Tang Yubo , Li Yan 
Published: August 2020

Abstract
In order to quantitatively analyze the impact of communication support capability on early-warning detection efficiency under electronic jamming condition, based on the study of the air-raid targets searching process, this paper build the detection probability calculating model of target indicating radar by evaluating the jamming efficiency of the air intelligence informing communication. Combined with the typical combat scenario, analysis of examples simulation is done and the results show that the jamming effect of using airborne jamming is better than using subgrade jamming on communication and the target indicating error which is caused by early-warning information does not affect the improvement of early warning detection capability.
State algorithm and double optimization design of safety cable retractor for gecko climbing robot
Authors: Gu Lizhi , Gao Shanping , Song Jinling , Xu Jianmin , Xiao Junyan , Chen Helu , Liang Chenglong 
Published: August 2020

Abstract
Gecko climbing robot cable is the core part of the robot system, which plays an important role in the basic life support of the operator. Based on the analysis of the function and performance requirements of the safety cable in the climbing process, the modular design scheme of the retractor is proposed according to the system engineering principle and optimization method, and the system is divided into retractor module, guidance and control module and mechanical structure module. Based on the analysis of the characteristics of the operator’s safety state during the climbing operation, the operator’s safety state set, the operator’s safety state set and the operator’s safety state set are formed. The whole process/full state algorithm is proposed. In the structural design, the basic functions of the retractor are divided into retractor module, guidance and control module and mechanical structure module. Considering the limited space and bearing capacity of the robot vehicle, on the premise of ensuring the safety and reliability, the lightweight optimization design is carried out to realize the function module and the double-pawl-bidirectional backstop-double-optimization retraction and release system with the most concise connection of each function module.
New Curve Fitting Based Roller Modification Method for Spherical Roller Bearing
Authors: Songyang Jia 
Published: August 2020

AbstractIn the field of roller modification affecting the service life of rolling bearings, Different from point contact of ball bearing and line contact of cylindrical or tapered roller bearing, Spherical roller bearing is very special because it has the characteristics of point contact and line contact at the same time. To solve the problem that the spherical roller cannot be modified by line contact type roller modification method, this paper provides a new modification method of spherical roller. The spherical roller profile is divided into two parts: non modification profile and modification profile. The concept of gap space is put forward. Curve fitting is carried out in the non modified part, and then the fitting logarithmic curve is used in the modified part of the spherical roller. This method can provide reference for engineering application.
Feasibility Analysis of Cross Wedge Rolling (CWR) of Hexahedral Billet
Authors: Chang Y , Shu X D , Chen T Z 
Published: August 2020

Abstract
In order to expand the product range of cross wedge rolling (CWR) and realize the CWR of hexahedral billet, the hexahedral CWR is studied. In this paper, a three-dimensional finite element model (FEM) of hexahedral cross wedge rolling is established by using DEFORM software. In this paper, a three-dimensional FEM of hexahedral CWR is established by using DEFORM finite element software. The change and distribution of equivalent stress and strain in the rolling process of hexahedral billets are analyzed. By tracking the strain in the rolling core of hexahedral billet, the change law of strain in each stage of forming process is obtained. The equivalent strain during the manufacturing process, the obtained CWR of hexahedral billet and round billet are basically the same. The feasibility of CWR of hexahedral billet is further verified by experiments. The research results provide theoretical guidance for realizing CWR of hexahedral billet.
Sound Quality Prediction of Fuel Cell Vehicles Based on Regression Analysis
Authors: Liu Zeyu , Liu Hai , Zhang Yanyi , Hao Dong , Sun Xiuxiu , Ji Xiang 
Published: August 2020

Abstract
The typical fuel cell vehicle(FCV)was taken as the research object. The noise test of the FCV was carried out in the environment of the semi-anechoic room of the vehicle. The noise samples in the vehicle were collected under the condition of constant speed, which was intercepted and processed with equal time. Noise was subjectively evaluated using a pairwise comparison method. The objective evaluation parameters suitable for evaluating the sound quality of FCV were selected. The objective evaluation parameters were calculated and solved. According to the subjective and objective evaluation results of sound quality, run multiple linear regression analysis to quantitatively solve the correlation between the subjective and objective evaluation results. MAPE results showed that the accuracy of the multiple linear regression prediction model was low, in order to further improve the accuracy of the prediction model of the sound quality of FCVs, The GA-BP neural network prediction model was used to establish the evaluation prediction model between the subjective and objective evaluation results. The weight of the influence of objective parameters on the subjective evaluation results was calculated. The MAPE calculation results showed that the neural network model was more suitable for the establishment of FCV sound quality prediction According to the model, A-weighting and roughness were the most influential to the subjective evaluation results. The two algorithms had the same results.
Progressive stamping process and die design of high strength steel automobile structural parts
Authors: Gen Yang , Yunong Wu 
Published: August 2020

Abstract
High strength steel has high strength and poor plasticity. When it is used in parts with large material thickness, complex shape and many working procedures, higher requirements are put forward for mold design. This paper introduced the forming characteristics, layout scheme, overall structure design of multi-station progressive die and design key points of important parts of a high-strength steel plate car mounting part. The progressive die including blanking, drawing, local forming and bending and other 13 processes was designed. The preforming and secondary forming were adopted to form the reinforcing ribs. The double-row with center carrier layout pattern was adopted to reduce the bending side force, and made the material utilization higher. The sub-die and insert structure’s using was convenient for die machining and debugging. The practice has proved that the die structure is reasonable and reliable, which can guarantee the quality of the products. It can be used as a reference for the design of similar products.
Variant design of typical aircraft parts based on CATIA technology
Authors: Hao B , Liu F , Liu M 
Published: August 2020

Abstract
In order to improve the efficiency of product design, the component framework technology was studied. With the help of CATIA secondary development platform, the variant design of typical aircraft parts was realized on the basis of parametric modeling technology, the feature information was extracted quickly, and the intelligent operation was realized. By using object-oriented programming language, a variant design module integrated with CATIA system is developed to improve the design efficiency of typical aircraft parts. Taking the tie rod in the typical aircraft parts as an example, the verification of the variation design method shows that using CATIA secondary development technology and CAA programming tools, the parametric modeling of typical aircraft parts can be achieved to achieve the variation design.