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An Information Entropy-Based Methodology to Construct the Avulsion Threshold in the Tail Reach of the Estuarine Alluvial Plain

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China Ocean Engineering 2023年第5期37卷 794-806页

作者： YANG Zhuo-yuan XIA Jun-qiang DENG Shan-shan ZHOU Mei-rong JI Zu-wen YU Xin State Key Laboratary of Water Resources and Management Wuhan UniversityWuhan 430072China Changjiang survey PlanningDesign and Research Co.LtdWuhan 430010China State Key Laboratary of Simulation and Regulation of River Basin Water Cycle China Insititute of Water Resources and Hydropower ResearchBeijing 100048China Yellow River Institute of Hydraulic Research Yellow River Conservancy CommisionZhengzhou 450003China

Channel avulsion is a natural phenomenon that occurs abruptly on alluvial river deltas,which can affect the channel *** causes for avulsion could be generally categorized as topography-and flood-driven ***,previous studies on avulsion thresholds usually focused on topography-driven factors due to the centurial or millennial avulsion timescales of the world’s most deltas,but neglected the impacts of flood-driven *** the current study,a novel demarcation equation including the two driven factors was proposed,with the decadal timescale of avulsion being considered in the Yellow River Estuary(YRE).In order to quantify the contributions of different factors in each category,an entropy-based methodology was used to calculate the contributing weights of these *** factor with the highest weight in each category was then used to construct the demarcation equation,based on avulsion datasets associated with the *** avulsion threshold was deduced according to the demarcation *** avulsion threshold was then applied to conduct the risk assessment of avulsion in the *** results show that:two dominant factors cover respectively geomorphic coefficient representing the topography-driven factor and fluvial erosion intensity representing the flood-driven factor,which were thus employed to define a two dimensional mathematical space in which the demarcation equation can be obtained;the avulsion threshold derived from the equation was also applied in the risk assessment of avulsion;and the avulsion threshold proposed in this study is more accurate,as compared with the existing thresholds.

关键词： avulsion threshold threshold conditions entropy weight method tail reach Yellow River Estuary

A survey on blockchain systems:Attacks,defenses,and privacy preservation

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High-Confidence Computing 2022年第2期2卷 7-26页

作者： Yourong Chen Hao Chen Yang Zhang Meng Han Madhuri Siddula Zhipeng Cai Zhejiang Shuren University HangzhouChina Changzhou University ChangzhouChina Binjiang insititute of Zhejiang University HangzhouChina Zhejiang University HangzhouChina North Carolina A&T State University GreensboroUSA Georgia State University AtlantaUSA

Owing to the incremental and diverse applications of cryptocurrencies and the continuous development of distributed system technology,blockchain has been broadly used in fintech,smart homes,public health,and intelligent transportation due to its properties of decentralization,collective maintenance,and *** the dynamism of blockchain abounds in various fields,concerns in terms of network communication interference and privacy leakage are gradually *** of the lack of reliable attack analysis systems,fully understanding some attacks on the blockchain,such as mining,network communication,smart contract,and privacy theft attacks,has remained ***,in this study,we examine the security and privacy of the blockchain and analyze possible *** systematical classify the blockchain attack techniques into three categories,then discuss the corresponding attack and defense methods based on these *** focus on(1)the attack and defense methods of mining pool attacks for blockchain security issues,such as block withholding,51%,pool hopping,selfish mining,and fork after withholding attacks,in the attack type of consensus excitation;(2)the attack and defense methods of network communication and smart contracts for blockchain security issues,such as distributed denial-of-service,Sybil,eclipse,and reentrancy attacks,in the attack type of middle protocol;and(3)the attack and defense methods of privacy thefts for blockchain privacy issues,such as identity privacy and transaction information attacks,in the attack type of application ***,we discuss future research directions for blockchain security.

关键词： Blockchain System Defense Attack Privacy

A major breakthrough in geological survey of coal measure gas in Southern Sichuan, China

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China geology 2020年第4期3卷 646-648页

作者： Cai-qin Bi Han-you Zhu Jia-qiang Zhang Yan-sheng Shan Yang Chen Huan-peng Chi Yong Luo Zhi-jun Zhang Oil and Gas Resources survey China Geological SurveyMinistry of Natural ResourcesBeijing 100083China Key Laboratory of Unconventional Oil and Gas geology China Geological SurveyMinistry of Natural ResourcesBeijing 100083China Sichuan insititute of Coal Field Geological Engineering Exploration and Designing Chengdu 610072China

*** Southern Sichuan is located in Xuyong-Junlian superimposed fold belt in the southern margin of Sichuan Foreland Basin,with an area of about 15000 km^*** coal measures of Upper Permian Xuanwei Formation and Longtan Formation are characterized by mudstone,clayey mudstone,fine sandstone,siltstone,and coal seams *** coal seams and carbonaceous mudstone have good hydrocarbon generation *** coal measure“three gas”includes coalbed methane(CBM),coal shale gas and coal measure tight sandstone gas *** was a breakthrough in the CBM survey in Junlian,Gulin,and other areas in Southern Sichuan(Yin ZS et al.,2019).But it lacks a comprehensive and systematic evaluation of coal measure gas resource potential.

关键词： mudstone sandstone survey

Interactions among Micronutrient Deficiencies and Undernutrition in the Philippines

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Biomedical and Environmental Sciences 1996年第2期9卷 348-357页

作者： R. F. FLORENTINO C. C. TANCHOCO M. P. RODRIGUEZ A. J. CRUZ AND W. L. MOLANO(Food and Nutrition Research insititute-Department of Science and Technology Science Compound Bicutan, Tagig, Metro Manila, Philippines) Food and Nutrition Research insititute-Department of Science and Technology Science Compound Bicutan Tagig Manila Philippines.

Data gathered from the 1987 National Nutrition survey in the Philippines provided the opportunity to study the interactions among micronutrient deficiencies and undernutrition in different age groups as basis for program targeting. A randomly selected set of 50% of the households (3,200) covered by the national survey served as source of subjects. Results showed that there was a greater proportion of anemia among the undernourished (as judged by weight for age in children and weight for height in adults) (66.0%)than among the adequately nourished (54.6%) (P <0.01 ). However, the observed differencesin the proportion of serum vitamin A deficiency and of goiter among the undernourished compared to the adequately nourished were not significant. Also not significant were the observed higher prevalence of anemia among subjects with acceptable serum vitamin A levels for both adequately nourished and undernourished, and the higher prevalence of vitamin A deficiency among the non-anemics. Again there were no significant differences in the prevalence of anemia among goitrous and non-goitrous subjects, as well as the prevalence of goiter among anemic and non-anemic subjects. Neither were there significant differences in the prevalence of vitamin A deficiency among goitrous and non-goitrous subjects, but there were significant differences in the prevalence of goiter among vitamin A deficient and non-vitamin A defjcient subjects among the 7-14 years old and among pregnant and lactating *** study concludes that at the national level, there is apparently an interaction between anemia and protein-energy undernutrition and possibly also between goiter and vitamin A deficiency in the high-risk age groups, but between anemia on the one hand and goiter and vitamin A deficiency in the other, perhaps because of clustering in the latter conditions not found in anemia and general undernutrition. These findings may be useful in targeting communities with high prevalence of micronutri

关键词： World Organization WHO Interactions among Micronutrient Deficiencies and Undernutrition in the Philippines

A Research of the Cretaceous-Paleogene Boundary in the Pingyi Basin, Shandong Province

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Open Journal of geology 2019年第10期9卷 661-664页

作者： Jun Chen Shengxian Du Cheng Chen Fengchen Liu Zhengguo Ning Xiangsuo Song Shucai Liu Huinan Lu Yongqing Liu Hongwei Kuang Shandong Institute of Geological Sciences Jinan China Key Laboratory of Gold Mineralization Processes and Resources Utilization Subordinated to the Ministry of Land and Resources Jinan China Key Laboratory of Metallogenic Geological Process and Resources Utilization in Shandong Province Jinan China Shandong Institute of Geological survey Jinan China Nanjing Institute of geology and Palaeontology Chinese Academy of Sciences Nanjing China insititute of geology Chinese Academy of Geological Sciences Beijing China

The Bianqiao Formation (in the Pingyi Basin, Shandong Province, China) is a typical set of continuous lacustrine carbonate deposits during the Cretaceous-Paleogene period, which is considered as an ideal stratigraphic unit for KPB research. This study is based on the borehole PYZK01, which is located at Tongjiazhuang village in Bianqiao Town of Pingyi country. According to biostratigraphy research, the Bianqiao Formtion establishes one charophyte assemblage: Porocharaanluensis-Charayuntaishanensis var. acuta-Turbocharaspecialis, and one sporopollen assemblage: Deltoidosporaadriensis-Rugubivesiculites- Schizaeoisporites. This result indicates that the stratigraphic age during 0 - 12.25 m is the Paleogene, 37.8 m - 60 m is the Late Cretaceous, and 12.25 - 37.8 m is a transition stage from the Late Cretaceous to the Paleocene. By geochemical study, it was established carbon and oxygen isotopic strata in the drill. Through the magnetostratigraphy research, we find eight positive polarity zones and seven reversed polarity zones, build the magnetic polarity sequences of the borehole, and propose a contrast scheme with the international standard magnetic polarity time column. After comprehensive discussion, it is preliminarily believed that the Cretaceous-Paleogene boundary is located at the depth of 31.98 m in PYZK01, namely, in the first section of the Bianqiao Fm.

关键词： Cretaceous-Paleogene Boundary Biostratigraphy Isotopic Stratigraphy Magnetostratigraphy Pingyi Basin

Association of Health-related Quality of Life with Health Examination and Lifestyles of Government Managers in China

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2007年第3期27卷 343-348页

作者：侯长荣吕斌卢祖询覃世龙 Department of Health Care Tongji HospitaTongji Medical College Huazhong Unversity of Science and Technology insititute of Environmental Medicine Tongji Medical College Huazhong Unversity of Science and Technology Department of Social Medicine School of Public Health Tongji Medical College Huazhong Unversity of Science and Technology

In order to study the association of each item of a health examination and lifestyles with health-related quality of life (HRQoL), a cross-sectional survey by a self-administered questionnaire using the 12-Item Short Form Health survey (SF-12, version 1) was conducted on 145 government managers that took health examinations in Tongji Hospital, Wuhan, China during 2005. The results showed that the determinations of organic functions including BMI, hemoglobin, blood platelet count, urine protein, urine WBC and lipid metabolism (LDL) were associated with HRQoL. The lifestyle items including age, sex, life satisfaction, drinking alcohol and kind of alcohol drunk, drinking tea, sleep quality and adhering to bedtime, working overtime, work stress were associated with HRQoL in the multiple regression models. Sex, age and life satisfaction were the lifestyle items most closely associated with HRQoL, while LDL, hemoglobin and urine protein were the health examination items most closely associated HRQoL. This study revealed that both lifestyle and health examination items were associated with HRQoL.

关键词： health promotion lifestyle health examination questionnaire quality of life