bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct measurement of the electron turbulence-broadening edge transport barrier to facilitate core–edge integration in tokamak fusion plasmas
Authors: Wang H.Q. , Hong R. , Jian X. , Rhodes T.L. , Guo H.Y. , Leonard A.W. , Ma X. , Watkins J.G. , Ren J. , Grierson B.A. , Shafer M.W , Scotti F. , Osborne T.H. , Thomas D.M. , Yan Z. 
Published: June 2023

Abstract
The integration of a high-performance core and a dissipative divertor, or the so-called ‘core–edge integration,’ has been widely identified as a critical gap in the design of future fusion reactors. In this letter, we report, for the first time, direct experimental evidence of electron turbulence at the DIII-D H-mode pedestal that correlates with the broadening of the pedestal and thus facilitates core–edge integration. In agreement with gyrokinetic simulations, this electron turbulence is enhanced by high η
e (η
e = Ln
/LT

e, where Ln
is the density scale length and LT

e is the electron temperature scale length), which is due to a strong shift between the density and temperature pedestal profiles associated with a closed divertor. The modeled turbulence drives significant heat transport with a lower pressure gradient that may broaden the pedestal to a greater degree than the empirical and theoretically predicted pedestal width scalings. Such a wide pedestal, coupled with a closed divertor, enables us to achieve a good core–edge scenario that integrates a high-temperature low-collisionality pedestal (pedestal top temperature T
e,ped > 0.8 keV and a pedestal top collisionality ν*ped < 1) under detached divertor conditions. This paves a new path toward solving the core–edge integration issue in future fusion reactors.
Electromagnetic turbulence simulation of tokamak edge plasma dynamics and divertor heat load during thermal quench
Authors: Zhu Ben , Xu Xue-qiao , Tang Xian-Zhu 
Published: June 2023

Abstract
The edge plasma turbulence and transport dynamics, as well as the divertor power loads during the thermal-quench phase of tokamak disruptions, are numerically investigated with BOUT++’s flux-driven six-field electromagnetic turbulence model. Here, transient yet intense particle and energy sources are applied at the pedestal top to mimic the plasma power drive at the edge induced by a core thermal collapse, which flattens the core temperature profile. Interesting features, such as surging of divertor heat load (up to 50 times) and broadening of heat-flux width (up to four times) on the outer-divertor target plate, are observed in the simulation, in qualitative agreement with experimental observations. The dramatic changes in divertor heat load and width are due to the enhanced plasma turbulence activities inside the separatrix. Two cross-field transport mechanisms, namely, the E × B turbulent convection and the stochastic parallel advection/conduction, are identified to play important roles in this process. First, an elevated edge pressure gradient drives instabilities and subsequent turbulence in the entire pedestal region. The enhanced turbulence not only transports particles and energy radially across the separatrix via the E × B convection, which causes the initial divertor heat-load burst, but it also induces amplified magnetic fluctuation

B
˜

. Once themagnetic fluctuation is large enough to break the magnetic flux surface, magnetic flutter effect provides an additional radial transport channel. In the late stage of our simulation,

|

B
˜

r

/

B
0

|

reaches to 10−4 level that completely breaks magnetic flux surfaces such that stochastic field lines are directly connecting pedestal top plasma to the divertor target plates or first wall, further contributing to the divertor heat-flux width broadening.
Study on the Phosphogypsum Proportion in Foamed Concrete Based on Concrete Strength and Carbon Emission
Authors: Peng Longfan , Yang Baochun , Deng Jingwen , Xu Xiaoyang , Zhang Shilu 
Published: June 2023

Abstract
The production of concrete will produce a lot of carbon dioxide and pollute the environment. Phosphogypsum is a solid waste generated during wet phosphoric acid treatment, and the use of phosphogypsum blending instead of cement in concrete production can effectively reduce carbon dioxide emissions. Then, experiments were conducted for six concrete groups with different phosphogypsum content as 0%~50% to test the strength in 3 days, 7 days, and 28 days. The results show that as the curing day rise, the compressive strength of concrete increases, meanwhile, with the increment of phosphogypsum content, the 28-day strength decreases significantly. The analysis for the consideration of the balance in carbon emission and the strength evolved, and results could be concluded that although the decrement of 28-day strength as well as the carbon dioxide emissions with the increasing phosphogypsum content in concrete, different trends were found. As the strength and emissions vary, a suggested range of content for phosphogypsum in concrete can be found. Based on these results, the proportion of phosphogypsum in concrete is proposed to achieve the purpose of energy saving and emission reduction and improve the utilization rate of phosphogypsum.
Research on Water-saving, Moisture-keeping and Curing Technology of Cement Stabilized Base Course of Highway
Authors: Wang Jie , Wang Jiangjiao , Xu Yang , Wang Wenyuan 
Published: June 2023

Abstract
The cement stabilized macadam base has excellent road performance and economy, and it is widely used. However, cement stabilized macadam also has some shortcomings such as poor anti-scour ability and insufficient frost resistance. To solve this problem, this study uses Scanning Electron Microscope (SEM) to analyze the micro-morphology of the specimen surface under four curing methods, namely moisturizing film, sack, polyethylene film and curing room, explaining the mechanism of curing methods affecting the anti-scour performance of cement stabilized macadam. Through the experimental study of anti-scour performance, it was found that the water-saving and moisturizing film was the closest to the experimental condition of curing in the curing room; the scour rates of the specimens of health-preserving sacks and polyethylene films were both high, and they were respectively 12.1g and 16.7g at 15m; through the experimental study of frost resistance, it was found that these curing methods had little influence on the frost resistance of cement stabilized macadam, and the ratio of compressive strength exceeded 0.6%.
Thermal Elastohydronamic Lubrication Characteristics of Inclined Double-roller Enveloping Hourglass Worm Drive
Authors: Li Jinkuan , Wen Yujie , Liu Zaixin 
Published: June 2023

Abstract
To grasp thermal elastohydrodynamic lubrication (TEHL) characteristics of the conjugating tooth-pairs of inclined double-roller enveloping hourglass worm drive in transmission process. The numerical solutions of line contact thermal EHL were obtained based on meshing theory of this worm drive and the theory of EHL. The TEHL line contact numerical solution of this worm drive is solved by using the multigrid method, and the TEHL film pressure and thickness are got at the same time. The effects of roller radius, offset distance, orifice coefficient and inclined angler on the TEHL characteristics and temperature rise are analysed and compared. The results show that with the increase of roller radius, offset distance and inclined angler, the secondary pressure peak decreases and moves to the outlet region, and the oil film thickness decreases accordingly, with increase in orifice coefficient the second pressure peak rises and move toward the inlet, the film thickness increases. The maximum temperature rises of film, worm and worm gear contact surface reduce as the roller radius, orifice coefficient and inclined angler increase, rose as the offset distance increases. It can reduce temperature rise and improve the oil film thickness thought the optimization calculation in the design.
Research Status and Development Trend of Sintered Solid Waste-based Wall Insulation Materials
Authors: Zhao Liang , Yao Shuang , Nan Yunxi , Qin Linyuan , Yi Shanmei 
Published: June 2023

Abstract
Improving the thermal performance of the building envelope and reducing the energy consumption of heat transfer are particularly important for building energy conservation. Wall insulation materials can be divided into sintered and non-sintered two types. Sintered wall insulation materials have unique advantages in the development of self-insulating wall because of their high strength, good insulation ability and wide range of raw materials. In this paper, the research status of shale, fly ash, coal gangue and phosphogypsum as raw materials to develop wall insulation materials are introduced, feasible research direction in view of the significantly reduced thermal performance and durability of sintered self-insulating wall materials in high humidity environment and high sintering temperature are put forward. The research on the formation and control mechanism of high closed porosity structure and the action mechanism of multiple fluxes can provide theoretical support for the design and optimization of self-insulation wall materials with light, high strength, low sintering temperature and meeting the requirements of building energy conservation.
Study on the Vibration Displacement of Hydraulic Pipeline System Excited by Fluid Impact
Authors: Zhou Zhijin , Wen Duo , Liu Aijun 
Published: June 2023

Abstract
Hydraulic impact had an effect on pipeline vibration displacement, so it was important to study the external lateral impact periodic force on fluid-structure coupling vibration displacement of hydraulic pipeline. Based on Bernoulli beam model, the fluid-structure coupling vibration equation of flexible pipeline was established by analyzing the stress of flexible pipeline under the action of internal flow. The hydraulic system pipeline was simulated whether the pipeline was subject to periodic impact force. The displacement-time curves in x, y and z directions of vibration monitoring points of hydraulic flexible pipelines were obtained, and the maximum displacement-time curves of fluid-structure coupling vibration under different pressure hydraulic impact were obtained. The simulation results were shown that the vibration of monitoring points in x, y and z directions of hydraulic impact pressure increased and the total displacement of the pipeline middle section of the hydraulic system decrease continuously, and then they tend to stabilize after a period of attenuation. The maximum displacement value of the X-direction monitoring point in the middle part of the hydraulic system pipeline was 9.5e
−5
m, and the displacement vibration was stable at 0.135s. The maximum y-displacement was 3.1e
−4m, and the vibration was stable at 0.2 s. The maximum z displacement was 1.32e-4 m, and the vibration was stable at 0.36 s. The total displacement was 3.35e
−4
m, and the vibration was stable at 0.43s. Increasing the impact pressure, the maximum displacement of the hydraulic pipeline vibrations were larger, and the attenuation of the maximum values were faster. The research results provide a reference for the hydraulic system to prevent pressure shock and reduce vibration.
The Method for Selecting Analogous Reservoirs Based on SEC
Authors: Liu Zhaolong , Geng Meng , Zhang Yongzhong 
Published: June 2023

Abstract
To support remaining economic recoverable reserves and undeveloped reserves compliant with SEC rules, different types of recovery analogous reservoir sequences need to be established. Based on the SEC reserves estimation standards and the actual development characteristics of the oilfield, a classified and optimal evaluation method of analogous reservoirs, which can select a reasonable analogous reservoir fast, has been proposed. This method mainly includes 7 steps to select analogous reservoirs. With practical application in an oilfield, this method has obtained good effects. Selection results can cover all the typical reservoir blocks, and it provides a reliable basis for analogizing the target reservoir in the future. The method herein could provide a new method to select analogous reservoirs based on SEC, and it can be widely used in other oil fields.
Modelling of Photovoltaic Modules Based on Hybrid Artificial Bee Colony Algorithm
Authors: Li Xiaofeng 
Published: June 2023

Abstract
In recent decades, the application of photovoltaic (PV) power generation and other new energy begins to attract people’s attention. The modelling of PV modules is significant for accurately estimating the generation power and electrical characteristic of the PV modules or arrays under complicated outdoor conditions. In this paper, a hybrid ABC algorithm is proposed. The model parameters of PV modules can be identified. In the proposed algorithm, three kinds of bees are hybrid, and they can complement each other and change roles dynamically, which makes the performance of the algorithm better than other basic optimization algorithms. Experimental results verify that the proposed hybrid ABC can effectively identify the model parameters and achieves better modelling accuracy of the I-V characteristics.
Laboratory Investigation of Cryogenic Fracturing of HDR Wellbores Under Triaxial-Confining stresses
Authors: Yang Zheqi , Zhang Baosheng , Bi Jianfei 
Published: June 2023

Abstract
Hot dry rock (HDR) contains abundant thermal energy, which can be extracted through fracturing and used for electricity generation. Due to its deep depth, high temperature and high-pressure conditions, it is difficult to initiate fractures for conventional hydraulic fracturing technology. This paper studies the advantage of cryogenic fracturing on the HDR. We have carried out a series of laboratory experiments on granite samples with different lengths of the open hole under triaxial-confining stresses (10 MPa). The nitrogen fracturing wellbores of high temperature (100−300 °C) granites are processed by LN2 (liquid nitrogen) and NoLN2 (no liquid nitrogen) and retained with 20 mm and 30 mm open hole to form four control groups. The fracturing results showed that LN2 cryogenic stimulation is more effective in reducing the HDR initiation pressure. With a 20 mm open hole, the breakdown pressure of samples with LN2 decreases by 13.9%-18.7% compared with untreated samples. When the open hole changes from 20 mm to 30 mm, the breakdown pressure of samples with NoLN2 is reduced by 6.7%-15%. The longer the open hole of the samples is, the more complex the fracture patterns after the nitrogen fracturing are. This can be attributed to the length of the open hole. The longer it is, the more complex the micro-fractures on the surface are, and the force of the direction parallel to the cross-section is significantly increased. The results of our research afford Enhanced Geothermal Systems (EGS) basics and help the early realization of thermal power generation from HDR.
Comprehensive Recovery of Valuable Metals from Lead-zinc Tailings by Flotation
Authors: Gao Tengyue , Ji Qiang , Li Guangsheng , Zhu Xingfu 
Published: June 2023

Abstract
This study takes lead-zinc flotation tailings as the research object. The process of “tailings regrinding-lead-zinc mixed floatation-activation zinc separation” is used to comprehensively recover valuable metal elements from the original tailings. The results show that the grinding fineness is -74 μm under the condition that m accounts for 82%; the recovery rates of lead and zinc in the lead-zinc mixed concentrate obtained from the open-circuit test are 36.4% and 18.0%, respectively; the recovery rate of zinc in the coarse zinc concentrate is 57.6%; the valuable metal elements in the original tailings are effectively recovered.
Study on Overpressure Explosion of Oil and Gas Pipelines and Risk Prevention & Control Measures
Authors: Liu Yan , Chen Lin , Wang Xuting , Zhao Yaqi , Zhao Zhen , Zhang Chen , Xu Jinghan 
Published: June 2023

Abstract
In view of the flammable and explosive characteristics of oil and gas pipeline transportation medium, once it leaks, production safety accidents are easy to occur. This study uses explosions with severe consequences caused by natural gas pipeline leakage as an example. The risk factors and accident modes of oil and gas storage and transportation pipelines are analyzed; the explosion load is calculated by a scaling explosion prediction model with the TNO multi-energy method; the relationship between overpressure load and combustible gas cloud radius is studied. The methane-air explosion volume fraction of 9.5% is taken as another example, with which the overpressure attenuation law of explosion wave is obtained. Based on the above research, safety risk prevention and control measures are proposed. The research results can provide technical support for daily management and risk prevention and control of oil and gas storage and transportation pipelines.
Unit health state prediction based on VMD-TCN
Authors: Xie Jie-min , Huang Bo , Tian Hai-ping , Pan wei-feng , Mo jian , Zheng hui-juan 
Published: June 2023

Abstract
To address the problem that it is difficult to accurately predict the health status of hydropower units using real-time monitoring data, this paper proposes a method for predicting the health status trend of hydropower units based on variational modal decomposition (VMD) and time convolution network (TCN); considering the nonlinear factors of the trend series of hydropower unit vibration index, a time series prediction model based on VMD-TCN is established to achieve accurate prediction of unit health status. And multiple sets of comparison experiments are designed to verify the higher accuracy and faster time of the proposed model.
Study on Hydrate Control Measures in Deepwater Gas Wellbore under Intervention Operations
Authors: Zou Fabao , Zhang Haixiang , Gan Bicheng , Xuan Yinglong , He Jingang , Zhang Zhibo 
Published: June 2023

Abstract
Hydrate control research is of great significance to the efficient development of deepwater gas wells. A deepwater gas well intervention wellbore hydrate suppression experimental device was built to simulate the field intervention operation and monitor the hydrate generation in the kettle in real time. The physical simulation experiments were conducted for the injection concentration, injection volume, and injection rate of the glycol inhibitor for different working conditions of the intervention operation. The results show that the hydrate inhibition effect is good when the injection concentration of glycol solution is 40%, the hydrate plugging in the wellbore is slow when the injection volume is 20 mL, and the hydrate inhibition is effective when the injection rate is 4 mL/min. The injection of glycol inhibitor can effectively delay the time required for wellbore hydrate plugging and ensure the intervention operation. The above research results provide ideas for in-wellbore hydrate control in deepwater gas well intervention operations in the field.
Online Calibration Based on Laser-Encoder Odometry
Authors: Gao Bingshu , Yu Dongdong , Chen Gong , Lu Wei 
Published: June 2023

Abstract
This paper proposes a new online calibration method for the differential-drive mobile robot equipped with a laser scanner. Our algorithm can jointly estimate the 3-DoF extrinsic parameters of the laser scanner and the intrinsic parameters (radii and wheel spacing) of the differential-drive kinematic model. Applying the pre-integration theory initially developed the for IMU sensor to the differential-drive kinematic model, we adopt iterative nonlinear optimization to minimize the cost derived from laser and encoder measurements. Experiments results confirm that the proposed method can do online calibration precisely.
Fiber Raman Amplifier Based on Improved Whale Algorithm
Authors: Yao Jiajia , Deng Huaqiu 
Published: June 2023

Abstract
In this paper, an improved whale algorithm to optimize pump power and wavelengths of second-order fiber Raman amplifier (FRA) has been proposed. Adopted by the strategies of adaptive gradients and reverse learning, the normal whale algorithm is greatly improved. An optimized FRA is designed based on the six-wavelength backward pump structure. Compared by optimizing both wavelength and power with optimizing only power, the gain flatness curves of the two algorithms, the optimal combination scheme, and the corresponding noise characteristics are got. A 6-pumped FRA has been designed in which the error of on-off gain is 0.08% and the ripple is only 0.18dB.
Infrared image enhancement algorithm based on improved wavelet threshold function and weighted guided filtering
Authors: Yang Haitao , Tong Yaonan , Cao Zhiqi , Chen Zhenguang 
Published: June 2023

Abstract
Aiming at the problems such as the poor visual effect of infrared thermal imaging under low illumination conditions, an enhanced infrared image recognition method based on wavelet decomposition is proposed for this paper. First, according to wavelet decomposition, the infrared image is divided into a low-frequency sub-band (LFS) and high-frequency sub-band (HFS) in each orientation, and HFS in each orientation is denoised using a modified wavelet threshold function to strengthen the denoising effect of the infrared image; Second, the multi-scale Retinex (MSR) algorithm based on weighted guided filtering (WGIF) is used to evaluate the component of illumination in the basic layer of the LFS, and the WGIF-segmented detail layer images are fused with the MSR processed ones to effectively highlight the texture details of the LFS; Finally, the LFS and the HFS are wavelets reconstructed (WR) to obtain the infrared enhanced images. This paper applies the algorithm to a low-resolution (resolution 32x32 pixels) infrared thermal imaging module, and the results of combining subjective and objective evaluation indexes show that the overall property index of the algorithm in this paper is superior to other contrasting algorithms and can effectively improve the infrared image quality.
A Novel Wave-transparent and Decoupling Antenna in Broadband Dual-Polarized Dual-Band Shared-Aperture Array
Authors: Lan Zhe-Peng , Zhang Rui , Sun Bao-Hua 
Published: June 2023

Abstract
This letter proposes a novel wave-transparent and decoupling antenna in broadband dual-Polarized dual-Band shared-aperture array. It is implemented by kneading the double-arrow-stripe-shaped decoupling structure into the frequency-selective metasurface structure of the lower-frequency-band (LFB) antenna arms. The LFB antenna radiator can be considered as frequency-selective and array-decoupling metasurface for the higher-frequency-band (HFB) antennas placed below. The antenna system consists of 2 × 2 HFB (3.3-3.6 GHz)arrays and an LFB (1.65-2.58 GHz) antenna with wave-transparent and decoupled structure (WTDS). Then, without adding additional structure, the in-band isolations of co- and cross-polarized between HFB antennas are promoted to >25.6 dB and >25 dB only by relying on the antenna form of the LFB antenna itself.
A Four-cell Division Method for Pilot Sequence Design to Reduce Pilot Pollution in Massive MIMO systems
Authors: Wang Qiong , Xiang Mo , Miao Sha 
Published: June 2023

Abstract
A method for pilot sequence design with the Zadoff-Chu (ZC) sequence as a base sequence is proposed to address the problem of pilot pollution in massive multi-input multi-output (MIMO) systems. Instead of the odd-length ZC sequence currently in use, the ZC sequence of even length serves as the basis of the pilot. It has the advantage of a very small cross-correlation coefficient under the premise that the sum of cyclic displacement is odd. The results of the four-cell division method are compared between the even-length and odd-length ZC pilot sequences. The MATLAB simulation shows that the signal-to-noise ratio and the channel estimation mean square error of the designed even-length ZC pilot sequence are better than those of the existing odd-length ZC pilot sequence in the case of four-cell division.