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Journal of Earth Science 2025年

作者： Jiangxia Wang Panpan Xu Hui Qian Yongqi Zang Qiming Wang Zhiyuan ma School of Water and Environment， Chang'an University Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education， Chang'an University Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of Ministry of Water Resources， Chang'an University

The Guanzhong Basin， located in Shaanxi Province， China， has abundant geothermal resources in its hinterland. Focusing on typical thermal reservoir structural units， namely the Xianli fault-step (XL) and Xi'an depression (XA)， this study reveals the genesis of geothermal water by combining hydrochemistry and environmental isotopes. The geothermal waters of XL uniformly correspond to the Na-Cl type with high contents of major ions， while the geothermal water of XA has complex hydrochemical types. The quartz geothermometer (with maximum steam loss) and Na-K-Ca geothermometer are recommended for XL and the quartz geothermometer (with no and maximum steam loss) and Na-K geothermometer for XA. Their temperature ranges are 99-159℃ and 93-146℃， respectively. The circulation depth of geofluids in XL and XA range from 2579 to 4766 m and from 2541 to 4330 m， with mean apparent ages of 21543 and 20345 yr B.P.， respectively. The geothermal water in XL originates from a mixture of sedimentary water and ancient infiltration water， and its formation mode was the vertical heat conduction with cooling process. In contrast， the geothermal water in XA originates from the dual process of cooling and mixing， with the process being dominated by ancient infiltration water and supplementation by modern infiltration water.

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Static recrystallization behavior of 25CrMo4 mirror plate steel during two-pass hot deformation

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Journal of Iron and Steel Research International 2017年第2期24卷 222-228页

作者： peng Zhou Qing-xian ma Department of Mechanical Engineering Tsinghua University Beijing 100084 China Key Laboratory for Advanced materials Processing Technology of Ministry of Education Tsinghua University Beijing 100084 China

The static recrystallization behavior of 25CrMo4 mirror plate steel has been determined by hot compression testing on a Gleeble 1500 thermal mechanical simulation tester. Compression tests were performed using double hit schedules at temperatures of 950-- 1 150 ~C, strain rates of 0.01--0.5 s-1 , and recrystallization time of 1--100 s. Results show that the kinetics of static recrystallization and the microstructural evolution were greatly influenced by the deformation parameters （deformation temperature, strain rate and pre strain） and the initial austenite grain size. Based on the experimental results, the kinetics model of static recrystallization has been generated and the comparison between the experimental results and the predicted results has been carried out. It is shown that the predicted results were in good agreement with the experimental results.

关键词： Hot deformation Static recrystallization 25CrMo4 Kinetics equation Microstructure

Theoretical study of interactions between human adult hemoglobin and acetate ion by polarizable force field and fragmentation quantum chemistry methods

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Science China Chemistry 2009年第11期52卷 1925-1931页

作者： YAN XiuFen JIANG nan ma Jing School of Chemistry and Chemical Engineering Institute of Theoretical and Computational ChemistryKey Laboratory of Mesoscopic Chemistry of MOENanjing UniversityNanjing 210093China

A series of theoretical approaches,including conventional FF03 and FF03-based polarization model,as well as the generalized energy-based fragmentation(GEBF) quantum chemistry method,have been applied to investigate the interactions between acetate ion(CH3COO-) and the α-subunit of human adult hemoglobin(designated as Hb-α) at four binding sites(Lys16,Lys90,Arg92,and Lys127),*** FF03-based polarizable force fields show that the interaction energies between the CH3COO-group and Hb-α follow the trend of Arg92>Lys127>Lys90>*** complexation of CH3COO-with Hb-α is governed by the long-range electrostatic interactions and steric effect.

关键词： polarization model fragmentation QM method hemoglobin interaction

Modelling the ZR Relationship of Precipitation Nowcasting Based on Deep Learning

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Computers, materials & Continua 2022年第7期72卷 1939-1949页

作者： Jianbing ma Xianghao Cui nan Jiang Chengdu University of Information Technology Chengdu610225China Bournemouth University BournemouthBH125BBUK

Sudden precipitations may bring troubles or even huge harm to people’s daily *** a timely and accurate precipitation nowcasting is expected to be an indispensable part of our modern ***,the rainfall intensity estimation from weather radar is based on the relationship between radar reflectivity factor(Z)and rainfall rate(R),which is typically estimated by location-dependent experiential formula and arguably ***,in this paper,we propose a deep learning-based method to model the ZR *** evaluate,we conducted our experiment with the Shenzhen precipitation *** proposed a combined method of deep learning and the ZR relationship,and compared it with a traditional ZR equation,a ZR equation with its parameters estimated by the least square method,and a pure deep learning *** experimental results show that our combined model performsmuch better than the equation-based ZRformula and has the similar performance with a pure deep learning nowcasting model,both for all level precipitation and heavy ones only.

关键词： Deep learning meteorology precipitation nowcasting weather forecasting ZR formula

Evaluation of aquatic rehabilitation technologies for polluted urban rivers and the case study of the Foshan Channel

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Frontiers of Environmental Science & Engineering 2010年第2期4卷 213-220页

作者： Haifeng JIA nan DONG Hongtao ma Department of Environmental Sciences&Engineering Tsinghua UniversityBeijing 100084China

An index system for evaluation of technologies for urban river rehabilitation was proposed and *** index system includes indicators of cost,resources,environmental improvement,and social *** calculation method for an objective value of each index based on its attributes and weights was *** Foshan Channel,which is a seriously polluted,black and malodorous urban river in Foshan City,China,was selected as a case *** values of the attributes and the weights of the indices for the Foshan Channel were *** technologies for the rehabilitation of the Foshan Channel were evaluated based on this index ***,a rehabilitation scheme for the Foshan Channel was proposed.

关键词： river rehabilitation urban rivers river pollution multi-objective analysis the Foshan Channel

A sparse autoencoder-based approach for cell outage detection in wireless networks

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Science China(Information Sciences) 2021年第8期64卷 253-254页

作者： Ziang ma Zhiwen PAN nan LIU National Mobile Communications Research Laboratory Southeast University

Dear editor,To meet the requirement of rapid growth in the number of mobile terminals and demand for network service quality from users, wireless networks must implement faster and more intelligent network operation and maintenance *** feasible solution is referred to as self-organizing networks(SON) [1]. As a use case of SON, self-healing technology is aimed to detect and diagnose network faults automatically and recover from them.

关键词： A sparse autoencoder-based approach for cell outage detection in wireless networks

A modified HEART risk score in chest pain patients with suspected non-ST-segment elevation acute coronary syndrome

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Journal of Geriatric Cardiology 2016年第1期13卷 64-69页

作者： Chun-peng ma Xiao WANG Qing-Sheng WANG Xiao-Li LIU Xiao-nan HE Shao-Ping NIE Emergency & Critical Care Center Beijing Anzhen Hospital Capital Medical University Beijing China Department of Cardiology the First Hospital of Qinhuangdao Hebei Medical University Hebei China Department of Endocrinology the First Hospital of Qinhuangdao Hebei Medical University Hebei China

ObjectiveTo validate a modified HEART [History, Electrocardiograph （ECG）, Age, Risk factors and Troponin] risk score in chest pain patients with suspected non-ST-segment elevation acute coronary syndrome （NSTE-ACS） in the emergency department （ED）.Methods This retrospective cohort study used a prospectively acquired database and chest pain patients admitted to the emergency department with suspected NSTE-ACS were enrolled. Data recorded on arrival at the ED were used. The serum sample of high-sensitivity cardiac Troponin I other than conventional cardiac Troponin I used in the HEART risk score was tested. The modified HEART risk score was calculated. The end point was the occurrence of major adverse cardiac events （maCE） defined as a composite of acute myocardial infarction （AMI）, percu-taneous intervention （PCI）, coronary artery bypass graft （CABG）, or all-cause death, within three months after initial *** A total of 1,300 patients were enrolled. A total of 606 patients （46.6%） had a maCE within three months： 205 patients （15.8%） were diag-nosed with AMI, 465 patients （35.8%） underwent PCI, and 119 patients （9.2%） underwent CABG. There were 10 （0.8%） deaths. A progres-sive, significant pattern of increasing event rate was observed as the score increased （P ＆lt; 0.001 byχ2 for trend）. The area under the receiver operating characteristic curve was 0.84. All patients were classified into three groups： low risk （score 0-2）, intermediate risk （score 3-4）, and high risk （score 5-10）. Event rates were 1.1%, 18.5%, and 67.0%, respectively （P ＆lt; 0.001）.ConclusionsThe modified HEART risk score was validated in chest pain patients with suspected NSTE-ACS and may complement maCE risk assessment and patients triage in the ED. A prospective study of the score is warranted.

关键词： Acute coronary syndrome Chest pain Emergency Risk assessment Troponin 1

An online data driven actor-critic-disturbance guidance law for missile-target interception with input constraints

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Chinese Journal of Aeronautics 2022年第7期35卷 144-156页

作者： Chi peng Jianjun ma Xiaoma LIU College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China

In this article,we develop an online robust actor-critic-disturbance guidance law for a missile-target interception system with limited normal acceleration ***,the missiletarget engagement is formulated as a zero-sum pursuit-evasion game *** key is to seek the saddle point solution of the Hamilton Jacobi Isaacs(HJI)equation,which is generally intractable due to the nonlinearity of the ***,based on the universal approximation capability of Neural Networks(NNs),we construct the critic NN,the actor NN and the disturbance NN,*** Bellman error is adjusted by the normalized-least square *** proposed scheme is proved to be Uniformly Ultimately Bounded(UUB)stable by Lyapunov ***,the effectiveness and robustness of the developed method are illustrated through numerical simulations against different types of non-stationary targets and initial conditions.

关键词： Actor-critic-disturbance structure Data driven Differential game Guidance systems Input constraints

Distributed Gradient Tracking Methods with Finite Data Rates

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Journal of Systems Science & Complexity 2021年第5期34卷 1927-1952页

作者： ma Xiaoyu YI peng CHEN Jie Department of Control Science and Engineering Tongji UniversityShanghai 200082China. Shanghai Research Institute for Intelligent Autonomous Systems Tongji UniversityShanghai 200082China

This paper studies the distributed optimization problem over an undirected connected graph subject to digital communications with a finite data rate,where each agent holds a strongly convex and smooth cost *** agents need to cooperatively minimize the average of all agents’cost *** agent builds an encoder/decoder pair that produces transmitted messages to its neighbors with a finite-level uniform quantizer,and recovers its neighbors’states by a recursive decoder with received quantized *** the adaptive encoder/decoder scheme with the gradient tracking method,the authors propose a distributed quantized *** authors prove that the optimization can be achieved at a linear rate,even when agents communicate at 1-bit data *** examples are also conducted to illustrate theoretical results.

关键词： Distributed optimization gradient tracking method quantization

Removal of phenol by activated alumina bed in pulsed high-voltage electric field

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Journal of Environmental Sciences 2007年第4期19卷 409-415页

作者： ZHU Li-nan ma Jun YANG Shi-dong School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

A new process for removing the pollutants in aqueous solution-activated alumina bed in pulsed high-voltage electric field was investigated for the removal of phenol under different conditions. The experimental results indicated the increase in removal rate with increasing applied voltage, increasing pH value of the solution, aeration, and adding Fe^2＋. The removal rate of phenol could reach 72.1% when air aeration flow rate was 1200 ml/min, and 88.2% when 0.05 mmol/L Fe^2＋ was added into the solution under the conditions of applied voltage 25 kV, initial phenol concentration of 5 mg/L, and initial pH value 5.5. The addition of sodium carbonate reduced the phenol removal rate. In the pulsed high-voltage electric field, local discharge occurred at the surface of activated alumina, which promoted phenol degradation in the thin water film. At the same time, the space-time distribution of gas-liquid phases was more uniform and the contact areas of the activated species generated from the discharge and the pollutant molecules were much wider due to the effect of the activated alumina bed. The synthetical effects of the pulsed high-voltage electric field and the activated alumina particles accelerated phenol degradation.

关键词： pulsed high-voltage electric field hybrid gas-liquid electrical discharge activated alumina phenol Fenton's reaction water treatment