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Simulation of rock mass balance of two typical altered rocks in Wulong gold deposit of Liaoning, China

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Journal of Central South University 2001年第3期13卷 197-202页

作者： wei jun-hao LIU Cong-qang LI Zhi-de Zhao Yong-xin Faculty of Earth Resources China University of GeosciencesWuhan 430074China Institute of Geochemistry Chinese Academy of SciencesGuiyang 550002China

Wulong gold deposit hosted in granite and fine-grained d io rite dikes, is a typical gold deposit of quartz vein type. Granite and fine-gra ined diorite dikes in the ore deposit were altered by metallogenic fluid. Based on the altered zoning, the samples of petrochemistry were collected and major an d trace elements were analyzed systematically. Calculation of rock mass balance shows that the major elements (SiO 2, K 2O, P 2O 5, Fe 2O 3) in the two ty pical altered rocks are clearly added into the altered system, and that trace el ements (V, Y, Zr, Ni, Co, Sr) assume an increasing and decreasing tendencies in the altered granite and altered diorite dike, respectively. The fluid/rock ratio s are 30.17-181.00 and 115.44-692.67 respectively for altered granite and alte red diorite dike, they have profoundly effects on metallogenesis.

关键词： altered rock rock mass balance Wulong gold deposit

Precipitation evolution and properties of Cu-15Ni-8Sn alloys via Al microalloying during ageing

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Rare Metals 2024年第10期43卷 5216-5228页

作者： wei Luo Li-jun Peng Xu-jun Mi hao-Feng Xie Yi-Cheng Cao Shu-Hui Huang State Key Laboratory of Nonferrous Metals and Processes GRINM Group Co.Ltd. GRIMAT Engineering Institute Co. Ltd. General Research Institute for Nonferrous Metals School of Materials Science and Engineering South China University of Technology

Studies have shown that microalloying Cu-Ni-Sn alloys using Al inhibits discontinuous precipitation reactions;however,the mechanism has not been investigated ***,this study explored the properties and precipitation evolution of Cu-15Ni-8Sn alloys without and with 1 wt%Al（Cu-15Ni-8Sn-1Al） during ageing at 500℃ through X-ray diffraction （XRD）,scanning electron microscopy and high-angle annular dark-field scanning transmission electron *** results revealed that in Cu-15Ni-8Sn alloy,DO22ordering first occurred after spinodal decomposition,subsequently transitioning to an L12ordering phase,during which the discontinuous precipitates gradually nucleated at the grain boundaries and formed *** alloy hardness increased sharply with ordering and then decreased rapidly after reaching its peak value,due to the dominance of the discontinuous precipitation ***,the DO22ordered phase did not appear during the ageing of Cu-15Ni-8Sn-1Al alloy,and a Ni3(Alx,Sn1-x) intermetallic compound with L12structure was formed,consuming Ni and Sn atoms,thereby significantly suppressing the discontinuous precipitation reaction and improving the stability during prolonged *** tensile strength （yield strength） of Cu-15Ni-8Sn and Cu-15Ni-8Sn-1Al alloys at peak hardness were 855 （755） and 936 MPa （892 MPa）,respectively,and their main strengthening mechanisms were solid solution strengthening and precipitation *** addition of 1 wt% Al effectively improved the precipitation strengthening effect of Cu-Ni-Sn alloys but severely decreased the ductility.

关键词： Al addition Cu-15Ni-8Sn Precipitation sequence Strengthening mechanism

Risk identification and safety assessment of human-computer interaction in integrated avionics based on STAMP

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Journal of Systems Engineering and Electronics 2024年第3期35卷 689-706页

作者： Zhao Changxiao LI hao ZHANG wei DAI jun DONG Lei School of Safety Science and Engineering Civil Aviation University of ChinaTianjin 300300China Shenzhen Dajiang Innovation Technology Co. Ltd.Shenzhen 518057China Key Laboratory of Civil Aircraft Airworthiness Technology Civil Aviation Administration of ChinaTianjin 300300China

To solve the problem of risk identification and quantitative assessment for human-computer interaction(HCI)in complex avionics systems,an HCI safety analysis framework based on system-theoretical process analysis(STPA)and cognitive reliability and error analysis method(CREAM)is *** can identify unsafe control actions and find the causal path during the interaction of avionics systems and pilot with the help of formal verification tools *** common performance conditions(CPC)of avionics systems in the aviation environment is established and a quantitative analysis of human failure is carried *** the head-up display(HUD)system interaction process as an example,a case analysis is carried out,the layered safety control structure and formal model of the HUD interaction process are *** the interactive behavior“Pilots approaching with HUD”,four unsafe control actions and35 causal scenarios are identified and the impact of common performance conditions at different levels on the pilot decision model are *** results show that HUD's HCI level gradually improves as the scores of CPC increase,and the quality of crew member cooperation and time sufficiency of the task is the key to its *** case analysis,it is shown that STPACREAM can quantitatively assess the hazards in HCI and identify the key factors that impact safety.

关键词： avionics human-computer interaction(HCI) safety assessment system-theoretic accident model and process human reliability analysis

Relationship of level of sex hormone and sex hormone receptor with development of metabolic syndrome in elderly men

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Journal of Geriatric Cardiology 2009年第4期6卷 199-203页

作者： Jian Li Jian Cao Bing-Po Zhu hao Wang wei-jun hao Hai-Yan Shi Yu Ding Xiao-Ying Li First Department of Geriatric Cardiology South Building Chinese PLA General Hospital Beijing 100853 China

Objective The sex hormone and the corresponding receptor may play some roles in the development of the metabolic syndrome （MS） in the elderly men. This study was designed to examine the relationship of level of the sex hormone and androgen receptor with MS in elderly men, thus to investigate the possible pathogenesis of MS. Methods This cross sectional study enrolled 587 elderly men, including 400 healthy controlls aged 62-92 years and 187 MS patients aged 60-87 years in Wan Shou Lu area of Beijing city. Dehydroepiandrosterone sulfate （DHAE-S）, total testosterone （TT）, sex hormone binding globulin （SHBG）, free testosterone （FT）, follicle-stimulating hormone （FSH）,Estradiol （E2）,luteinizing hormone（LH） and androgen receptor （AR） in blood were tested. Statistical analyses included the comparison analysis of variables and independent variables, correlation analysis using multi-factor linear regression, and multiple logistic regression analysis. Results DHAE-S, TT, SHBG, FT and AR fluorescence intensity in healthy control group were higher than those in MS group, however, FSH and E2 levels were lower in healthy group. Age was negatively correlated with diastolic blood pressure （DBP） and FT, but positively correlated with systolic blood pressure （SBP） and E2. AR fluorescence intensity was negatively correlated with SBP and LH. The logistic regression equation showed the negative correlation between DHEA-S, SHBG and the development of MS. Conclusions There are low levels of DHEA-S, TT, SHBG, FT and AR in the elderly patients with MS. On the contrary, FSH and E2 concentration are higher. It can be suggested that low levels of DHEA-S and SHBG may be the potential risk factors of MS in elderly men.

关键词： metabolic syndrome sex hormones receptor, androgen

Investigation on UV-curing Reprocessable Thermosets Bearing Hindered Urea Bonds and Their Composites with Modified Zinc Oxide Nanoparticles

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Chinese Journal of Polymer Science 2024年第6期42卷 751-765页

作者： jun-hao Zhou Li-Ming Tang Key Laboratory of Advanced Materials of Ministry of Education of China Department of Chemical EngineeringTsinghua UniversityBeijing100084China

In this study,a series of hindered urea bond(HUB)containing polyurethane-urea methacrylate prepolymers and a none HUB containing polyurethane methacrylate prepolymer were prepared using isobornyl methacrylate as the reactive diluent via one-pot *** prepolymers were characterized fully by various ***,their thermosets were fabricated via UV curing in presence of a photo initiator,and their mechanical property and thermal behavior were investigated and *** from the none HUB containing thermoset,the HUB containing thermosets(defined as PUT)could be recycled and reprocessed by hot press under relatively mild conditions with high recovery ratio of mechanical ***,zinc oxide(ZnO)nanoparticles were modified with 3-(trimethoxysilyl)propyl methacrylate and the modified ZnO(defined as ZnO-TPM)was dispersed and polymerized into PUT matrix to prepare their *** influence of ZnO-TPM on the mechanical performance of the composites was evaluated,which indicated that the Young’s modulus and tensile strength increased gradually to the maximum values at ZnO-TPM content of 1 wt%and then *** composites also displayed good reprocessability with improved recovery ratio compared to the pure PUT *** addition,the composite materials exhibited strong UV absorption capacity,implying their potential application in the circumstance where UV-shielding was required.

关键词： Polyurethane-urea methacrylate Hindered urea bond ZnO nanoparticles Reprocessing UV curing

Joint UAV trajectory and communication design with heterogeneous multi-agent reinforcement learning

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Science China(Information Sciences) 2024年第3期67卷 225-245页

作者： Xuanhan ZHOU jun XIONG Haitao Zhao Xiaoran LIU Baoquan REN Xiaochen ZHANG Jibo wei hao YIN College of Electronic Science and Technology National University of Defense Technology Systems Engineering Institute Academy of Military Sciences PLA

Unmanned aerial vehicles(UAVs) are recognized as effective means for delivering emergency communication services when terrestrial infrastructures are unavailable. This paper investigates a multiUAV-assisted communication system, where we jointly optimize UAVs’ trajectories, user association, and ground users(GUs)’ transmit power to maximize a defined fairness-weighted throughput metric. Owing to the dynamic nature of UAVs, this problem has to be solved in real time. However, the problem’s non-convex and combinatorial attributes pose challenges for conventional optimization-based algorithms, particularly in scenarios without central controllers. To address this issue, we propose a multi-agent deep reinforcement learning(MADRL) approach to provide distributed and online solutions. In contrast to previous MADRLbased methods considering only UAV agents, we model UAVs and GUs as heterogeneous agents sharing a common objective. Specifically, UAVs are tasked with optimizing their trajectories, while GUs are responsible for selecting a UAV for association and determining a transmit power level. To learn policies for these heterogeneous agents, we design a heterogeneous coordinated QMIX(HC-QMIX) algorithm to train local Q-networks in a centralized manner. With these well-trained local Q-networks, UAVs and GUs can make individual decisions based on their local observations. Extensive simulation results demonstrate that the proposed algorithm outperforms state-of-the-art benchmarks in terms of total throughput and system fairness.

关键词： unmanned aerial vehicle (UAV) trajectory design resource allocation multi-agent deep reinforcement learning (MADRL) heterogeneous agents

UDT:U-shaped deformable transformer for subarachnoid haemorrhage image segmentation

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CAAI Transactions on Intelligence Technology 2024年第3期9卷 756-768页

作者： wei Xie Lianghao Jin Shiqi Hua hao Sun Bo Sun Zhigang Tu jun Liu Hubei Provincial Key Laboratory of Artificial Intelligence and Smart Learning Central China Normal UniversityWuhanChina School of Computer Science Central China Normal UniversityWuhanChina National Language Resources Monitoring and Research Center for Network Media Central China Normal UniversityWuhanChina The First Affiliated Hospital of Dalian Medical University DalianChina State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina Information Systems Technology and Design Pillar Singapore University of Technology and DesignSingaporeSingapore

Subarachnoid haemorrhage(SAH),mostly caused by the rupture of intracranial aneu-rysm,is a common disease with a high fatality *** lesions are generally diffusely distributed,showing a variety of scales with irregular *** complex characteristics of lesions make SAH segmentation a challenging *** cope with these difficulties,a u-shaped deformable transformer(UDT)is proposed for SAH ***,first,a multi-scale deformable attention(MSDA)module is exploited to model the diffuseness and scale-variant characteristics of SAH lesions,where the MSDA module can fuse features in different scales and adjust the attention field of each element dynamically to generate discriminative multi-scale ***,the cross deformable attention-based skip connection(CDASC)module is designed to model the irregular edge char-acteristic of SAH lesions,where the CDASC module can utilise the spatial details from encoder features to refine the spatial information of decoder ***,the MSDA and CDASC modules are embedded into the backbone Res-UNet to construct the proposed *** experiments are conducted on the self-built SAH-CT dataset and two public medical datasets(GlaS and MoNuSeg).Experimental results show that the presented UDT achieves the state-of-the-art performance.

关键词： image segmentation medical image processing

Establishing a predictive model for aspirin resistance in elderly Chinese patients with chronic cardiovascular disease

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Journal of Geriatric Cardiology 2016年第5期13卷 458-464页

作者： Jian CAO wei-jun hao Ling-Gen GAO Tian-Meng CHEN Lin LIU Yu-Fa SUN Guo-Liang HU Yi-Xin HU Li FAN Department of Geriatric Cardiology Chinese PLA General Hospital Beijing China Health Division of Guard Bureau General Staff Department of Chinese PLA Beijing China

Background Resistance to anti-platelet therapy is detrimental to patients. Our aim was to establish a predictive model for aspirin resistance to identify high-risk patients and to propose appropriate intervention. Methods Elderly patients （n = 1130） with stable chronic coronary heart disease who were taking aspirin （75 mg） for 〉 2 months were included. Details of their basic characteristics, laboratory test results, and medications were collected. Logistic regression analysis was performed to establish a predictive model for aspirin resistance. Risk score was finally established according to coefficient B and type of variables in logistic regression. The Hosmer-Lemeshow （HL） test and receiver operating characteristic curves were performed to respectively test the calibration and discrimination of the model. Results Seven risk factors were included in our risk score. They were serum creatinine （〉 110 μmol/L, score of 1）; fasting blood glucose （〉 7.0 mmol/L, score of 1）; hyperlipidemia （score of 1）; number of coronary arteries （2 branches, score of 2; 〉 3 branches, score of 4）; body mass index （20-25 kg/m2, score of 2; 〉 25 kg/m2, score of 4）; percutaneous coronary intervention （score of 2）; and smoking （score of 3）. The HL test showed P ≥ 0.05 and area under the receiver operating characteristic curve ≥ 0.70. Conclusions We explored and quantified the risk factors for aspirin resistance. Our predictive model showed good calibration and discriminative power and therefore a good foundation for the further study of patients undergoing anti-platelet therapy.

关键词： Aspirin resistance Cardiovascular disease Predictive model Risk score

Adaptive Memetic Algorithm with Dual-Level Local Search for Cooperative Route Planning of Multi-Robot Surveillance Systems

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Complex System Modeling and Simulation 2024年第2期4卷 210-221页

作者： hao Cheng Jin Yi wei Xia Huayan Pu jun Luo the State Key Laboratory of Mechanical Transmission for Advanced Equipment Chongqing UniversityChongqing 400044China the Department of Electronics Information and BioengineeringPolitecnico di MilanoMilano 20133Italy

The heightened autonomy and robust adaptability inherent in a multi-robot system have proven pivotal in disaster search and rescue,agricultural irrigation,and environmental *** study addresses the coordination of multiple robots for the surveillance of various key target positions within an *** involves the allocation of target positions among robots and the concurrent planning of routes for each *** tackle these challenges,we formulate a unified optimization model addressing both target allocation and route ***,we introduce an adaptive memetic algorithm featuring dual-level local search *** algorithm operates independently among and within robots to effectively solve the optimization problem associated with *** proposed method’s efficacy is substantiated through comparative numerical experiments and simulated experiments involving diverse scales of robot teams and different target positions.

关键词： multi-robot system surveillance memetic algorithm