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Exact Solutions to the Bidirectional SK-Ramani Equation

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Communications in Mathematical Research 2019年第4期35卷 289-300页

作者： Zou Jia-hui wang yun-hu Gao Wen-jie College of Science University of Shanghai for Science and TechnologyShanghai200093 College of Art and Sciences Shanghai Maritime UniversityShanghai201306 不详

In this paper,the bidirectional SK-Ramani equation is investigated by means of the extended homoclinic test approach and Riemann theta function method,*** on the Hirota bilinear method,exact solutions including one-soliton wave solution are obtained by using the extended homoclinic approach and one-periodic wave solution is constructed by using the Riemann theta function method.A limiting procedure is presented to analyze in detail the relations between the one periodic wave solution and one-soliton solution.

关键词： Hirota bilinear method bidirectional Sawada-Kotera equation extended homoclinic test approach Riemann theta function

FATIGUE CRACK PROPAGATION IN Al-Li ALLOY 8090

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Acta Metallurgica Sinica(English Letters) 1992年第6期5卷 436-442页

作者： wang Zhongguang ZHANG yun hu Zhuangqi State Key Laboratory for Fatigue and Fracture of Materials,Institute of Metal Research,Academia Sinica,Shenyang,ChinaHE Shiyu LI Qingjian Harbin Institute of Technology,Harbin,China Professor Institute of Metal Research Academia SinicaShenyang 110015China

Fatigue crack growth rates of Al-Li alloy 8090 in air were found to be strongly dependent up- on the aging *** naturally aged and underaged specimens showed the highest re- sistance to the fatigue crack *** fatigue crack growth resistance of the overaged specimen is the lowest and that of the peakaged specimen in *** compared to air, 3.5% NaCl solution does not change the effect of aging conditions on the fatigue crack growth,but causes a decrease of the resistance to the fatigue crack growth under the same ag- ing *** short cracks from notch and physically short cracks showed much higher rates of fatigue crack propagation in comparison with long cracks under the same aging condi- tion and stress intensity *** growth behavior of the short crack depends on its *** growth rate of short crack from notch decreases first to a minimum and then increases with in- creasing △***,the physically short crack grows at a progressively increasing rate. The effects of aging conditions are explained in terms of the slip planarity of dislocations and the cyclic slip *** observed short crack behavior is considered to be dependent on the crack closure and the local plasticity near the crack tip.

关键词： Al-Li alloy fatigue crack closure effect slip planarity

Vacuum chamber suppression of gas-explosion propagation in a tunnel

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Journal of China University of Mining and Technology 2008年第3期18卷 337-341页

作者： JIANG Shu-guang WU Zheng-yan LI Qing-hua HE Xin-jian SHAO Hao QIN Jun-hui wang Lan-yun hu Li-ming LIN Bai-quan School of Safety Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

To control and reduce the harm of a gas explosion, a new method is proposed for suppressing gas-explosion propagation in a tunnel by using a vacuum chamber. We studied the suppression effect on gas explosions by placing a vacuum chamber at dif-ferent positions along the tunnel. The results indicate that: 1) the vacuum chamber can absorb the explosion wave and explosion energy as much as possible at the beginning of the gas explosion, and; 2) when the vacuum chamber is used the closer it is to the ignition source the more significant the suppression effect. In addition, by using the vacuum chamber: 1) the flame propagation velocity decreases from ultrasonic to subsonic; 2) the flame propagation distance is remarkably shortened; 3) the maximum peak value of overpressure (pm) decreases from 0.34 to 0.17 MPa or less, and; 4) the impulse of the blast wave (I) decreases from 20 to 8 kPa·s or less.

关键词： vacuum chamber liquid venting flame quenching pressure venting impulse explosion suppression

Left ventricular reconstruction with no-patch technique：early and late clinical outcomes

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Chinese Medical Journal 2010年第23期123卷 3412-3416页

作者： hu Sheng-shou FAN Hong-guang ZHENG Zhe FENG Wei wang Wei SONG yun-hu wang Li-qing YUAN Xin ZHANG Shi-ju Department of Cardiovascular Surgery Research Center for Cardiovascular Regenerative Medicine Fu Wai Hospital Peking Union Medical College and Chinese Academy of Medical Sciences Beijing 100037 China

Background Few studies have evaluated late clinical outcome of no-patch technique in patients with large left ventricular aneurysms. The objectives of this study were to evaluate a no-patch surgical technique to reconstruct the left ventricle in patients with left ventricular aneurysm and to assess early and late clinical *** In 1995, we began using a no-patch technique in patients with dyskinetic left ventricular aneurysms. A total of 145 patients underwent left ventricular reconstruction with this technique and were followed up for （59±29） months （range,1-127 months）. Risk factors for early mortality were analyzed by bivariate analyses. Cox＇s proportional hazards model was used to calculate risk factors for all-cause mortality and hospital readmission. Kaplan-Meier methodology was used to analyze late *** One week after operation, left ventricular end-diastolic diameter had decreased from （61±8） mm to （55±8）mm, and geometry of the left ventricle was restored to a more normal conical shape. Early mortality was 3% and late mortality 11%. Over a 5-year follow-up period, hospital readmission was 28%. One-, 5-, and 10-year survival estimates were 95% （95% confidence interval （CI） 91%-99%）, 86% （95% CI 78%-94%）, and 74% （95% CI 60%-88%）.Readmission-free survival at 1 and 5 years after operation was 87% （95% CI81%-93%） and 60% （95% CI50%-70%）,*** The no-patch technique for left ventricular reconstruction is an effective and simple procedure that can achieve satisfactory early and late clinical outcomes in patients with left ventricular aneurysms.

关键词： left ventricular reconstruction no-patch technique follow-up clinical outcome

Effect of Nb-V microalloying on the hot deformation behavior of medium Mn steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 360-368页

作者： Yumeng wang Qinyi Guo Bin hu Haiwen Luo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow *** concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.

关键词： medium manganese steel niobium-vanadium microalloying flow behavior dynamic recrystallization hot workability

IoT Empowered Early Warning of Transmission Line Galloping Based on Integrated Optical Fiber Sensing and Weather Forecast Time Series Data

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Computers, Materials & Continua 2025年第1期82卷 1171-1192页

作者： Zhe Li yun Liang Jinyu wang Yang Gao State Grid Henan Electric Power Company Electric Power Scientific Research Institute State Grid Henan Electric Power CompanyZhengzhou450052China

Iced transmission line galloping poses a significant threat to the safety and reliability of power systems,leading directly to line tripping,disconnections,and power *** early warning methods of iced transmission line galloping suffer from issues such as reliance on a single data source,neglect of irregular time series,and lack of attention-based closed-loop feedback,resulting in high rates of missed and false *** address these challenges,we propose an Internet of Things(IoT)empowered early warning method of transmission line galloping that integrates time series data from optical fiber sensing and weather ***,the method applies a primary adaptive weighted fusion to the IoT empowered optical fiber real-time sensing data and weather forecast data,followed by a secondary fusion based on a Back Propagation(BP)neural network,and uses the K-medoids algorithm for clustering the fused ***,an adaptive irregular time series perception adjustment module is introduced into the traditional Gated Recurrent Unit(GRU)network,and closed-loop feedback based on attentionmechanism is employed to update network parameters through gradient feedback of the loss function,enabling closed-loop training and time series data prediction of the GRU network ***,considering various types of prediction data and the duration of icing,an iced transmission line galloping risk coefficient is established,and warnings are categorized based on this ***,using an IoT-driven realistic dataset of iced transmission line galloping,the effectiveness of the proposed method is validated through multi-dimensional simulation scenarios.

关键词： Optical fiber sensing multi-source data fusion early warning of galloping time series data IoT adaptive weighted learning irregular time series perception closed-loop attention mechanism

Genetic Analysis and Primary Mapping of pms4, a Photoperiod-Sensitive Genic Male Sterility Gene in Rice (Oryza sativa)

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Rice science 2008年第2期15卷 153-156页

作者： huANG Ting-you wang Zhi hu yun-gao SHI Shou-pei PENG Tao Chu Xu-dong SHI Jun XIANG Zu-fen LIU Ding-you Mianyang Agricultural Science Research Institute Mianyang 621023 China

To understand the genetic characteristics of a new photoperiod-sensitive genic male sterile line Mian 9S, some reciprocal crosses were made between Mian 9S and six indica rice materials, Yangdao 6, Luhui 602, Shuihui 527, Mianhui 725, Fuhui 838 and Yixiang 1B. Genetic analysis results suggested that the photoperiod-sensitive genic male sterility （PGMS） of Mian 9S was controlled by a single recessive nuclear gene. Thus, the F2 population derived from the cross of Yangdao 6/Mian 9S was used to map the PGMS gene in Mian 9S. By using SSR markers, the PGMS gene of Mian 9S was mapped on one side of the markers, RM6659 and RM1305, on rice chromosome 4, with the genetic distances of 3.0 cM and 3.5 cM, respectively. The gene was a novel PGMS gene and designated tentatively as pms4. In addition, the application of the pms4 gene was discussed.

关键词： genetic analysis gene mapping photoperiod-sensitive genic male sterility rice (Oryza sativa)

Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 181-191页

作者： Senkuan Meng Zheng wang Ruisong Zhu Ruijie Liu Jiang Ma Lina hu Weihua wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University College of Mechatronics and Control Engineering Shenzhen University Songshan Lake Materials Laboratory Institute of Physics Chinese Academy of Sciences

As a microforming technique, micro/nano-structural replication possesses advantages of high precision and efficiency. With the remarkable superplasticity in the supercooled liquid region, amorphous alloys or metallic glasses(MGs) are regarded as ideal materials for miniature fabrication. However, due to the intrinsic metastable nature of supercooled liquids, the design of imprinting processes for MGs poses a challenge. In the past, process parameters have largely relied on trial-and-error *** this work, a low-frequency active force modulation system is employed to apply a stable, precise, and real-time feedback stress field for imprinting of MG samples. Low-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled liquid. With the dataset composed of orthogonal experiments, a machine learning strategy based on back-propagation(BP) neural networks was utilized to construct a 3D parameter space for temperature, stress, and time, and to predict the corresponding filling ratio. Furthermore, the optimal combination of imprinting process parameters was identified, and its filling ratio was experimentally validated to reach as high as 0.94. The near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter design. At the same time, this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning

A functional cathode sodium compensation agent for stable sodium-ion batteries

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Green Energy & Environment 2025年第1期10卷 173-182页

作者： Wei Wu Zhenglin hu Zhengfei Zhao Aoxuan wang Jiayan Luo Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China Shanghai Jiao Tong University Shaoxing Research Institute of Renewable Energy and Molecular Engineering Shaoxing312000China

Hard carbon(HC)is widely used in sodium-ion batteries(SIBs),but its performance has always been limited by lowinitial Coulombic efficiency(ICE)and cycling *** compensation agent is a favorable strategy to make up for the loss of active sodium ions consumed *** it lacks agent that effectively decomposes to increase the active sodium ions as well as regulate carbon defects for decreasing the irreversible sodium ions ***,we propose 1,2-dihydroxybenzene Na salt(NaDB)as a cathode compensation agent with high specific capacity(347.9 mAh g^(-1)),lower desodiation potential(2.4–2.8 V)and high utilization(99%).Meanwhile,its byproduct could functionalize HC with more C]O groups and promote its reversible ***,the presodiation hard carbon(pHC)anode exhibits highly reversible capacity of 204.7 mAh g^(-1) with 98%retention at 5 C rate over 1000 ***,with 5 wt%NaDB initially coated on the Na3V2(PO4)3(NVP)cathode,the capacity retention of NVP t NaDBjHC cell could increase from 22%to 89%after 1000 cycles at 1 C *** work provides a new avenue to improve reversible capacity and cycling performance of SIBs through designing functional cathode compensation agent.

关键词： Hard carbon ICE Cathode compensation agent Reversible capacity Stability