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A Critical Examination to the Unitarized IJ ＝ 20 ππ Scattering Chiral Amplitude

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Communications in Theoretical Physics 2001年第11期36卷 563-568页

作者： ANG qin xiao zhi-Guang ZHENG Han-qing SONG Xing-Chang Department of Physics Peking UniversityBeijing 100871China Department of PhysicsPeking UniversityBeijing 100871China Department of PhysicsPeking UniversityBeijing 100871China Department of PhysicsPeking UniversityBeijing 100871China

We discuss the Padé approximation to the ππ scattering amplitudes in one-loop chiral perturbation *** approximation restores unitarity and can reproduce the correct resonance poles,but the approximation violates crossing symmetry and produces spurious poles on the complex s plane and therefore plagues its predictions in some *** we find that one virtual state in the IJ = 20 channel may have physical relevance.

关键词： ππ scattering,Padé approximation,chiral perturbation theory

The Effects of Demographic Features on Differences in Sensitivity between PCL-C and SCL-90 Scores in a Follow-up Study in Secondary School Students in the Wenchuan Earthquake Region

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Biomedical and Environmental Sciences 2011年第6期24卷 642-648页

作者： HOU Feng Su LI Ting LI Juan HU xiao qin LIU zhi Yue YUAN Ping Department of Epidemiology West China School of Public Health Sichuan University Chengdu 610041 SichuanChina

Objective To analyze the sensitivity of effect factors between the PCL-C and the SCL-90, to provide evidence for social psychological crisis screening and post-trauma interventions. Methods We administered the PCL-C and SCL-90 to screen for PTSD and other psychological problems among students who survived the disaster and continued their school studies. The surveys were carried out 3, 6, 9, and 12 months after the earthquake. A bivariate 2-level logistic model was used to explore the different levels of sensitivity among students. The factors influencing the relationships between PTSD and depression, and between PTSD and anxiety were examined. Results We analyzed data from 1677 students, revealing that female students in higher grades were more likely to exhibit symptoms of depression, rather than PTSD, compared with the control group （males in lower grades）, and the difference was significant （P〈0.05）. In contrast, ethnic minorities were more likely to exhibit PTSD symptoms compared to the others. In addition, female students were more likely to exhibit symptoms of anxiety than PTSD. Other effects that did not reach statistical significance were suggested to have a similar influence on PTSD, depression, and anxiety. Conclusion After a natural disaster, specific aspects of depression and anxiety should be examined, avoiding an overemphasis on PTSD in social psychological crisis interventions.

关键词： PTSD Depression Anxiety Bivariate 2-Level Logistic Model Students Natural disaster survivors

Some Convergence Properties for ψ-Mixing Sequences

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Journal of Mathematical Research and Exposition 2011年第3期31卷 443-450页

作者： Xue Jun WANG Shu He HU xiao qin LI Wen zhi YANG School of Mathematical Science Anhui University Anhui 230039 P. R. China

In this paper,we extend the Kolmogorov-type inequality to the case of ψ-mixing ***,we study the strong limit theorems for partial sums of ψ-mixing random *** a result,we extend the Khintchine-Kolmogorov-type converg... 详细信息

关键词： Kolmogorov-type inequality Khintchine-Kolmogorov-type convergence theorem strong law of large numbers.

Cavitation evolution and damage by liquid nitrogen in a globe valve

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第2期23卷 101-117页

作者： Xia ZHOU xiao-qin zhi Xu GAO Hong CHEN Shao-long ZHU Kai WANG Li-min QIU xiao-bin ZHANG Institute of Refrigeration and Cryogenics Zhejiang UniversityHangzhou 310027China State Key Laboratory of Technologies in Space Cryogenic Propellants Beijing 100028China

Valves are key components of the safety of fluid transportation systems because of induced disturbance and cavitation damage in *** this study,a 2D model of a cryogenic globe valve with liquid nitrogen(LN_(2))as working fluid was established by Fluent,and thermal effects were specially considered in the *** validity of the LN_(2) cavitation model was verified by the experimental data of hydrofoil LN_(2) cavitation from earlier studies by *** characteristics of LN2 in the cryogenic globe valve under three typical working conditions were *** average pressure and pressure pulse at different positions of the wall were further studied to reveal cavitation risks from fatigue and *** show that with similar valve structure and openings,the pressure pulsation frequencies of LN_(2) are lower than those of water,and the shape and location of the cavitation clouds also show significant *** LN_(2) cavitation,an extended period of valve opening at 66% should be avoided since its pressure pulse peak is the largest compared to openings of 33% and 100%,and reaches 5×10^(7) *** opening of 33% should also be monitored because of the large torque caused by the pressure difference between the two sides of the valve *** prevent resonance,a critical state for the valve opening and the connecting pipe length is *** predictions of cryogenic cavitation in the globe valve are helpful for the safe and reliable operation of cryogenic fluid transport systems.

关键词： Cavitation Thermal effect Cryogenic liquids Cryogenic globe valve

Prospects on mangrove knowledge services in the smart era: From plant atlas to knowledge graphs

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Science China Earth Sciences 2025年第1期68卷 111-127页

作者： zhi-Wei HOU Wenlong JING Cheng-zhi qin Ji YANG qing XIA xiaoling YIN Key Laboratory of Guangdong for Utilization of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and Application Guangzhou Institute of Geography Guangdong Academy of Sciences Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences School of Traffic & Transportation Engineering Changsha University of Science and Technology

Mangroves are crucial to the ecological security of the Earth and human well-being. Their management, conservation, and restoration are of great importance and necessitate the support of spatio-temporal information and multidisciplinary knowledge such as biology and ecology. Traditional knowledge services such as plant atlas provide illustrated textual knowledge of mangroves. However, this kind of service is oriented to information retrieval and is incapable of effectively mining and utilizing fragmented knowledge from multi-source heterogeneous data, facing the problem of “massive data, rare knowledge”. Knowledge graphs are capable of extracting, organizing, and fusing the knowledge contained in massive data into semantic networks that can be understood and computed by computers. They provide a solution for the realization of intelligent knowledge services. Focusing on the urgent need for mangrove knowledge acquisition, formal representation, and intelligent services, this paper proposes a research prospect on mangrove knowledge graphs and knowledge services. We first analyze the similarities and differences between various domain-specific concepts of Tupu. On this basis, we define the mangrove knowledge graph as a large-scale knowledge base that integrates multi-disciplinary knowledge and spatio-temporal information with mangrove ecosystems as the core. Then, we propose a research framework for mangrove knowledge services that can realize the transformation from multi-modal data to intelligent knowledge services, including multiple research levels such as ubiquitous data sensing and aggregation, knowledge organization and graph construction, and intelligent mangrove knowledge services. Subsequently, the methods and workflow for constructing mangrove knowledge graphs are introduced. Finally, we discuss the challenges and possible future directions of mangrove knowledge services in the smart era, including the construction of a mangrove knowledge system that integra

关键词： Mangrove Tupu Knowledge graph Multi-modal Knowledge service

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两种后路脊柱融合方法治疗腰椎不稳的比较

中国现代医学杂志 2010年第8期20卷 1269-1272,1275页

作者：肖志勤湖南省安化县人民医院骨科湖南安化413500

目的对比分析后外侧横突间植骨融合与经后路椎体间植骨融合术治疗腰椎不稳的疗效。方法 54例腰椎不稳患者分为横突间植骨融合组(A组)25例,椎体间植骨融合组(B组)29例。两组年龄、病程、术前临床表现及影像学资料相近似。A组大部分进行... 详细信息

目的对比分析后外侧横突间植骨融合与经后路椎体间植骨融合术治疗腰椎不稳的疗效。方法 54例腰椎不稳患者分为横突间植骨融合组(A组)25例,椎体间植骨融合组(B组)29例。两组年龄、病程、术前临床表现及影像学资料相近似。A组大部分进行了后路椎板减压,B组全部进行了后路椎板减压,两组均进行了椎弓根钉系统复位与固定。结果 A组手术时间平均187 min,出血量平均640 mL,B组组手术时间平均250min,出血量平均980 mL,两组慢性下腰痛均明显改善,临床疗效两组间无显著性差异。骨融合率A组84%,B组96.5%(P=0.014);优良率A组88%,B组93.1%,两组无显著性差异(P>0.05)。结论横突间植骨与椎体间植骨是目前两种治疗腰椎退行性不稳症疗效确切的方法。两者治疗腰椎不稳的疗效相近,椎体间植骨融合率高,内固定失败率低,但手术创伤较大,失血较多。对没有神经根症状或神经根受压行"开窗"或半椎板切除的患者,横突间植骨不失为一种简便有效的植骨融合方式。对严重不稳定型椎管狭窄、椎体滑脱行全椎板切除患者,建议行椎间植骨融合。

关键词：腰椎不稳定后外侧横突间植骨融合后路椎体间植骨融合

GPS: graph contrastive learning via multi-scale augmented views from adversarial pooling

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Science China(Information Sciences) 2025年第1期68卷 145-158页

作者： Wei JU Yiyang GU Zhengyang MAO Ziyue QIAO Yifang qin xiao LUO Hui XIONG Ming ZHANG School of Computer Science National Key Laboratory for Multimedia Information ProcessingPeking University Artificial Intelligence Thrust The Hong Kong University of Science and Technology Department of Computer Science University of California

Self-supervised graph representation learning has recently shown considerable promise in a range of fields, including bioinformatics and social networks. A large number of graph contrastive learning approaches have shown promising performance for representation learning on graphs, which train models by maximizing agreement between original graphs and their augmented views(i.e., positive views). Unfortunately, these methods usually involve pre-defined augmentation strategies based on the knowledge of human experts. Moreover, these strategies may fail to generate challenging positive views to provide sufficient supervision signals. In this paper, we present a novel approach named graph pooling contrast(GPS) to address these *** by the fact that graph pooling can adaptively coarsen the graph with the removal of redundancy, we rethink graph pooling and leverage it to automatically generate multi-scale positive views with varying emphasis on providing challenging positives and preserving semantics, i.e., strongly-augmented view and weakly-augmented view. Then, we incorporate both views into a joint contrastive learning framework with similarity learning and consistency learning, where our pooling module is adversarially trained with respect to the encoder for adversarial robustness. Experiments on twelve datasets on both graph classification and transfer learning tasks verify the superiority of the proposed method over its counterparts.

关键词： graph representation learning graph neural networks graph contrastive learning graph augmentations graph pooling

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电话传输心电信息的应用

医学信息（西安上半月） 2007年第8期20卷 1333-1335页

作者：秦孝智延边大学附属医院吉林延吉133000

电话传输心电信息技术是在医学不断发展的基础上,随着计算机网络和通信技术的发展而形成的心血管疾病新的诊断技术。本文首先介绍了电话传输心电信息技术的概念和基本组成,接着介绍了其特点以及临床应用情况,最后介绍了存在的问题和发... 详细信息

电话传输心电信息技术是在医学不断发展的基础上,随着计算机网络和通信技术的发展而形成的心血管疾病新的诊断技术。本文首先介绍了电话传输心电信息技术的概念和基本组成,接着介绍了其特点以及临床应用情况,最后介绍了存在的问题和发展前景。

关键词：电话传输心电监护通讯技术计算机网络

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老年冠心病患者的心率变异性分析

吉林医学 2008年第11期29卷 901-902页

作者：秦孝智延边大学附属医院心内科吉林延吉133000

目的:探讨老年冠心病患者的心率变异性及其临床价值。方法:应用24h动态心电图对79例老年冠心病患者进行HRV分析,并与68例正常对照者比较。结果:老年冠心病患者HRV的时域和频域指标即SDNN、SDANNI、TI、LF及LF/HF较对照组明显降低(P(0.01... 详细信息

目的:探讨老年冠心病患者的心率变异性及其临床价值。方法:应用24h动态心电图对79例老年冠心病患者进行HRV分析,并与68例正常对照者比较。结果:老年冠心病患者HRV的时域和频域指标即SDNN、SDANNI、TI、LF及LF/HF较对照组明显降低(P(0.01)。而两组RR间期、rMSSD、HF差异无显著性(P(0.05)。结论:老年冠心病患者存在心脏自主神经失调,老年冠心病患者的HRV降低,表明交感神经活性及迷走神经活性均受损,迷走神经活性受损更为严重,两者协调作用失衡。

关键词：冠心病心率变异性动态心电图