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The Two Main Mechanisms of Glacier Lake Outburst Flood in Tibet,China

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Journal of Mountain Science 2013年第2期10卷 239-248页

作者： LIU Jing-jing TANG Chuan cheng zun-lan Key Laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences State Key Laboratory of Geohazard Preventions Graduate School of Chinese Academy of Sciences

With the global warming,the disasters of Glacier Lake Outburst Flood(GLOF) have taken place frequently in Tibet in recent years and attracted more and more attention.A systematic survey was conducted on the 19 GLOFs in Tibet to study their two main *** indicated that all the events occurred in end-moraine lakes,and the outburst occurred partially and *** the breach had the shape of an arc or a trapezoid in overflow outburst and its top width was 3-5 times more than the *** two main mechanisms of GLOFs in Tibetan end-moraine Lake were overflow and piping,and the overflow mechanism caused by iceberg collapse was dominated in most cases.A formula was proposed to calculate the critical thickness of iceberg tongue that determines the *** analysis of the moraine materials revealed that seepage deformation is crucial in the outburst ***,we conducted a case study of the Guangxiecuo Lake to show its possible process of outburst and estimated the peak discharge of the resulted flood.

关键词： Glacier Lake Outburst Flood End-moraine Lake Outburst mechanism Overflow Piping Tibet

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气温对西藏冰湖溃决事件的影响

吉林大学学报（地球科学版） 2011年第4期41卷 1121-1129页

作者：刘晶晶唐川程尊兰刘宇中国科学院水利部成都山地灾害与环境研究所成都610041 成都理工大学地质灾害防治与地质环境保护国家重点实验室成都610059 中国科学院山地灾害与地表过程重点实验室成都610041 中国科学院研究生院北京100039 中国水电顾问集团成都勘测设计研究院成都610072

西藏冰湖溃决是多因素引发的突发事件。由于溃决冰湖多位于高海拔、人烟稀少的地方,对于其独特的地貌因素、构造成分提取十分困难,所以作者仅研究气温这一易获取的重要因素对西藏冰湖溃决的影响。冰湖溃决与气候的波动变化有着密切联系... 详细信息

西藏冰湖溃决是多因素引发的突发事件。由于溃决冰湖多位于高海拔、人烟稀少的地方,对于其独特的地貌因素、构造成分提取十分困难,所以作者仅研究气温这一易获取的重要因素对西藏冰湖溃决的影响。冰湖溃决与气候的波动变化有着密切联系,在全球平均地表温度持续上升的背景下,研究气温对于西藏冰湖溃决的影响,是十分重要的。考察了西藏的14次溃决事件,结合邻近12个溃决冰湖的9个气象站的年值气象资料和日值气象资料进行分析,发现冰湖溃决是年均温剧烈波动后区域响应的结果,波动越大,冰湖溃决发生的几率越大。还研究了溃决当年和溃决前一年的正积温值(T)和积温增长速度(积温拟合曲线指数a),发现溃决事件发生当年的正积温值和积温增长速度普遍大于溃决的前一年。根据正积温值与积温拟合曲线指数,建立幂函数曲线公式来界定易溃决事件和不易溃决事件。根据上述分析,推荐选择长序列的正积温值与积温曲线指数,作为考量指标以研究西藏冰湖溃决事件。

关键词：西藏气温冰湖溃决影响

Cleaner production of 3.5 valent vanadium electrolyte from ammonium metavanadate by ammonia reduction-sulfuric acid dissolution method

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Tungsten 2024年第3期6卷 555-560页

作者： cheng Wang lan-Jie Li Hao Du College of Chemical Engineering University of Chinese Academy of Sciences Institute of Process Engineering National Engineering Research Center of Green Recycling for Strategic Metal Resources Chinese Academy of Sciences Hesteel Group Company Limited

The vanadium redox flow battery(VRFB) has been widely used in large-scale energy storage areas due to the advantages of long lifespan and high safety. However, the high preparation cost of vanadium electrolyte limits ... 详细信息

关键词： Ammonia

A unified pre-training and adaptation framework for combinatorial optimization on graphs

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Science China Mathematics 2024年第6期67卷 1439-1456页

作者： Ruibin Zeng Minglong Lei Lingfeng Niu lan cheng School of Computer Science and Technology University of Chinese Academy of SciencesBeijing100049China Faculty of Information Technology Beijing University of TechnologyBeijing100124China School of Economics and Management University of Chinese Academy of SciencesBeijing100190China School of Mathematics and Statistics Central South UniversityChangsha410075China

Combinatorial optimization(CO)on graphs is a classic topic that has been extensively studied across many scientific and industrial ***,solving CO problems on graphs through learning methods has attracted great *** deep learning methods,e.g.,graph neural networks(GNNs),have been used to effectively assist the process of solving ***,current frameworks based on GNNs are mainly designed for certain CO problems,thereby failing to consider their transferable and generalizable abilities among different COs on ***,simply using original graphs to model COs only captures the direct correlations among objects,which does not consider the mathematical logicality and properties of *** this paper,we propose a unified pre-training and adaptation framework for COs on graphs with the help of the maximum satisfiability(Max-SAT)*** first use Max-SAT to bridge different COs on graphs since they can be converted to Max-SAT problems represented by standard formulas and clauses with logical *** we further design a pre-training and domain adaptation framework to extract the transferable and generalizable features so that different COs can benefit from *** the pre-training stage,Max-SAT instances are generated to initialize the parameters of the *** the fine-tuning stage,instances from CO and Max-SAT problems are used for adaptation so that the transferable ability can be further *** experiments on several datasets show that features extracted by our framework exhibit superior transferability and Max-SAT can boost the ability to solve COs on graphs.

关键词： combinatorial optimization graph neural networks domain adaptation maximum satisfiability problem

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川藏公路东久河下游段路基水毁防护工程对策

四川大学学报（工程科学版） 2005年第3期37卷 5-9页

作者：程尊兰张正波耿学勇中国科学院水利部成都山地灾害与环境研究所四川成都610041 西藏自治区交通科学研究所西藏拉萨850000

针对川藏公路东久河下游段特殊水文水力条件和自然环境特征,选择(K4113+280～K4113+365)典型水毁段为例,对该段路基水毁的形成因素、特征、活动规律及公路路基水毁防护经验教训分析,根据野外路基防护工程冲刷模拟试验,建立适合该段路基... 详细信息

针对川藏公路东久河下游段特殊水文水力条件和自然环境特征,选择(K4113+280～K4113+365)典型水毁段为例,对该段路基水毁的形成因素、特征、活动规律及公路路基水毁防护经验教训分析,根据野外路基防护工程冲刷模拟试验,建立适合该段路基护墙冲刷深度计算公式,在保证足够基础埋深的基础上,提出了浆砌石挡土墙+钢丝网混凝土护坦的长期(永久性)防护工程方案,为西藏高山峡谷区沿河路基水毁防护工程建设提供了示范。

关键词：川藏公路路基水毁钢丝网混凝土护坦

Modifications in aroma characteristics of'Merlot'dry red wines aged in American,French and Slovakian oak barrels with different toasting degrees

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Food Science and Human Wellness 2024年第1期13卷 381-391页

作者： Haocheng Lu Binhao cheng Yibin lan Changqing Duan Fei He Center for Viticulture and Enology College of Food Science and Nutritional EngineeringChina Agricultural UniversityBeijing 100083China Key Laboratory of Viticulture and Enology Ministry of Agriculture and Rural AffairsBeijing 100083China

Aging in oak barrels is widely used in enology which could bring flavor changes and aromatic complexity to *** the present study,the aroma compounds were analyzed from the‘Merlot’dry red wines,which were fermented in two types of fermenters(stainless steel tank and rotated oak barrel)and aged in six types of oak barrels(three geographic origins×two toasting degrees)for different time(0,3,6 and 9 months,respectively).Results showed that 30 volatiles were associated with barrels and increased during oak *** fermenters could influence the intensities of the toast,leathery,smoky,fruity,floral and caramel *** concentration of whisky lactone,eugenol,cis-isoeugenol,and the intensities of the toast and spicy aromas were highest in the wines aged in American oak and were lowest in the wines aged in French oak *** concentrations of guaiacol,syringol,trans-isoeugenol,furfural alcohol,vanilla,cis-whisky lactone enabled the medium toasting barrels to be distinguished from the light toasting *** compounds originating from the barrels could be used to distinguish the types of different barrels,but the other general grape-derived and fermentation-derived volatiles could *** fermenters,oak species and toasting degrees of the barrels all had significant effects on the aroma profiles of the aged‘Merlot’dry red wines,but the influence of the geographic origin was not obvious.

关键词： Wine Aroma Oak Barrel Oak species Toasting degrees Geographic origin Aging

Structured Multi-Head Attention Stock Index Prediction Method Based Adaptive Public Opinion Sentiment Vector

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Computers, Materials & Continua 2024年第1期78卷 1503-1523页

作者： cheng Zhao Zhe Peng Xuefeng lan Yuefeng Cen Zuxin Wang School of Economics Zhejiang University of TechnologyHangzhouChina College of Management Zhejiang University of TechnologyHangzhouChina Informatization Office Zhejiang University of TechnologyHangzhouChina School of Information and Electronic Engineering Zhejiang University of Science&TechnologyHangzhouChina School of Economics and Management Universiti Putra MalaysiaDaerah PetalingNegeri SelangorMalaysia

The present study examines the impact of short-term public opinion sentiment on the secondary market,with a focus on the potential for such sentiment to cause dramatic stock price fluctuations and increase investment *** quantification of investment sentiment indicators and the persistent analysis of their impact has been a complex and significant area of *** this paper,a structured multi-head attention stock index prediction method based adaptive public opinion sentiment vector is *** proposedmethod utilizes an innovative approach to transform numerous investor comments on social platforms over time into public opinion sentiment vectors expressing complex *** then analyzes the continuous impact of these vectors on the market through the use of aggregating techniques and public opinion data via a structured multi-head attention *** experimental results demonstrate that the public opinion sentiment vector can provide more comprehensive feedback on market sentiment than traditional sentiment polarity ***,the multi-head attention mechanism is shown to improve prediction accuracy through attention convergence on each type of input information *** absolute percentage error(MAPE)of the proposedmethod is 0.463%,a reduction of 0.294% compared to the benchmark attention ***,the market backtesting results indicate that the return was 24.560%,an improvement of 8.202% compared to the benchmark *** results suggest that themarket trading strategy based on thismethod has the potential to improve trading profits.

关键词： Public opinion sentiment structured multi-head attention stock index prediction deep learning

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西藏古乡沟泥石流与气象条件的关系

科学技术与工程 2015年第9期35卷 45-49,55页

作者：刘建康程尊兰中国地质科学院探矿工艺研究所中国地质调查局地质灾害防治技术中心成都611734 中国科学院成都山地灾害与环境研究所/中国科学院山地灾害与地表过程重点实验室成都610041

古乡沟位于西藏波密县境内,是发育在念青唐古拉山脉冰川边缘地区的一条大型冰川泥石流沟。自1953年暴发特大泥石流以来,在夏秋季节连续高温或多雨的气候条件下,就会频繁暴发泥石流,几次至百余次不等。为了研究古乡沟泥石流活动与气象条... 详细信息

古乡沟位于西藏波密县境内,是发育在念青唐古拉山脉冰川边缘地区的一条大型冰川泥石流沟。自1953年暴发特大泥石流以来,在夏秋季节连续高温或多雨的气候条件下,就会频繁暴发泥石流,几次至百余次不等。为了研究古乡沟泥石流活动与气象条件的关系,以古乡沟1964~1965年暴发的中等及以上规模泥石流（Qmax≥50 m3/s）作为研究对象,结合所在期间（5~9月）的气象资料,通过非参数检验方法,发现泥石流暴发与日降雨R和日最高气温Tmax存在密切关系。最后,分别就多雨（R≥5 mm）和少雨（R〈5 mm）两种气象条件下,分别讨论泥石流暴发概率与降雨和气温的关系,其相关性好。

关键词：冰川泥石流 Kolmogorov-Smirnov检验气象条件西藏

Effect of multiple coulomb scattering on the beam tests of silicon pixel detectors

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Nuclear Science and Techniques 2024年第4期35卷 200-207页

作者： lan-Kun Li Ming-Yi Dong Ze Gao Liang-cheng-Long Jin Shu-Jun Zhao School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Particle Detection and Electronics(Institute of High Energy Physics CAS)Beijing 100049China University of Chinese Academy of Science Beijing 100049China University of South China Hengyang 421001China

In the research and development of new silicon pixel detectors,a collimated monoenergetic charged-particle test beam equipped with a high-resolution pixel-beam telescope is crucial for prototype verification and performance *** the beam energy is low,the effect of multiple Coulomb scattering on the measured resolution of the Device Under Test(DUT)must be considered to accurately evaluate the performance of the pixel chips and *** study aimed to investigate the effect of multiple Coulomb scattering on the measured resolution,particularly at low beam *** were conducted using Allpix^(2) to study the effects of multiple Coulomb scattering under different beam energies,material budgets,and telescope *** simulations also provided the minimum energy at which the effect of multiple Coulomb scattering could be *** with the results of a five-layer detector system tested with an electron beam at DESY,the simulation results were consistent with the beam test results,confirming the reliability of the simulations.

关键词： Silicon Pixel Detectors Beam Telescope Multiple Coulomb Scattering Spatial Resolution