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Character Formulas for a Class of Simple Restricted Modules over the Simple Lie Superalgebras of Witt Type

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Chinese Annals of Mathematics,Series B 2020年第1期41卷 49-60页

作者： Yu-feng yao Department of Mathematics Shanghai Maritime UniversityShanghai 201306China

Let F be an algebraically closed field of prime characteristic, and W(m, n, 1) be the simple restricted Lie superalgebra of Witt type over F, which is the Lie superalgebra of superderivations of the superalgebra ■(m;1) ■∧(n), where ■(m;1) is the truncated polynomial algebra with m indeterminants and ∧(n) is the Grassmann algebra with n indeterminants. In this paper, the author determines the character formulas for a class of simple restricted modules of W(m, n, 1) with atypical weights of type Ⅰ.

关键词： Restricted Lie superalgebra Witt type Lie superalgebra Restricted representation Typical(atypical) weight Character formula

Ice-and-snow tourism and its sustainable development in China: A new perspective of poverty alleviation

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Advances in Climate Change Research 2021年第6期12卷 881-893页

作者： AN Hong-Min XIAO cun-De TONG yao FAN Jie State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing100875China Climate Change Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing100029China Yingkou Meteorological Bureau Yingkou110001China Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China

The development of ice-and-snow tourism (IST) has great potential for poverty alleviation and is of great significance for promoting the sustainable development of alpine areas. However, little attention has been given to evaluating the suitability and potential of ice-and-snow tourism in poverty-stricken areas. Taking 832 poverty-stricken counties in China as samples, this study proposed an integrity suitability index (ISI) based on natural and socioeconomic factors to evaluate the suitability and potential of developing ice-and-snow tourism in poverty-stricken counties. The results showed that there are significant differences between the spatial distributions of the suitability of glacier- and ski-related tourism. The former is mainly distributed in the Qinghai‒Tibet Plateau, while the latter is distributed in low-altitude mountainous areas. Additionally, 36.0% of the total number of poverty-stricken counties have the potential to match medium-to high-level ISIs of ice-and-snow tourism, of which 2.5%, 32.9% and 0.2% are suitable for glacier excursions, ski sports and both, respectively. Furthermore, climate change and environmental protection are the main constraints on the development of ice-and-snow tourism and corresponding development strategies are proposed. This study can provide references for scientific planning and policy making regarding the sustainable development in poverty-stricken areas.

关键词： Ice-and-snow tourism Poverty alleviation Cryosphere service Sustainable development Ski tourism Glacier tourism

Knowledge modeling based on interval-valued fuzzy rough set and similarity inference: prediction of welding distortion

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第8期15卷 636-650页

作者： Zhi-qiang feng cun-gen LIU Hu HUANG Maritime College Qinzhou University State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University

Knowledge-based modeling is a trend in complex system modeling technology. To extract the process knowledge from an information system, an approach of knowledge modeling based on interval-valued fuzzy rough set is presented in this paper, in which attribute reduction is a key to obtain the simplified knowledge model. Through defining dependency and inclusion functions, algorithms for attribute reduction and rule extraction are obtained. The approximation inference plays an important role in the development of the fuzzy system. To improve the inference mechanism, we provide a method of similaritybased inference in an interval-valued fuzzy environment. Combining the conventional compositional rule of inference with similarity based approximate reasoning, an inference result is deduced via rule translation, similarity matching, relation modification, and projection operation. This approach is applied to the problem of predicting welding distortion in marine structures, and the experimental results validate the effectiveness of the proposed methods of knowledge modeling and similarity-based inference.

关键词： Knowledge modeling Interval-valued fuzzy rough set Similarity-based inference Welding distortion prediction

Projective Synchronization in Modulated Time-Delayed Chaotic Systems Using an Active Control Approach

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Chinese Physics Letters 2011年第12期28卷 55-58页

作者： feng cun-Fang WANG Ying-Hai School of Electronic and Electrical Engineering Wuhan Textile UniversityWuhan 430073 Institute of Theoretical Physics Lanzhou UniversityLanzhou 730000

Projective synchronization in modulated time-delayed systems is studied by applying an active control *** on the Lyapunov asymptotical stability theorem,the controller and sufficient condition for projective synchronization are calculated *** give a general method with which we can achieve projective synchronization in modulated time-delayed chaotic *** method allows us to adjust the desired scaling factor *** effectiveness of our method is confirmed by using the famous delay-differential equations related to optical bistable or hybrid optical bistable *** simulations fully support the analytical approach.

关键词： method projective applying

Primary squamous cell carcinoma of the liver associated with hepatolithiasis:A case report

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World Journal of Gastroenterology 2012年第40期18卷 5830-5832页

作者： Ke-Lei Zhu Ding-yao Li cun-Bing Jiang Department of Hepatopancreatobiliary Surgery Yin Zhou People's HospitalNingbo 315040Zhejiang ProvinceChina

Primary squamous cell carcinoma(SCC) of the liver is rare and reported *** to date,only 24 such cases have been reported in the *** is associated with hepatic teratoma,congenital cysts,solitary benign non-parasitic hepatic cysts,hepatolithiasis/Caroli's disease or *** reported a case of primary SCC of the liver associated with multiple intrahepatic cholesterol *** patient underwent hepatectomy followed by radiotherapy,and has survived for over 19 mo without recurrence.

关键词： Hepatolithiasis Surgery Radiotherapy Squa-mous cell carcinoma

Extreme precipitation detection ability of four high-resolution precipitation product datasets in hilly area:a case study in Nepal

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Advances in Climate Change Research 2024年第3期15卷 390-405页

作者： Sunil Subba yao-Ming Ma Wei-Qiang Ma cun-Bo Han Land-Atmosphere Interaction and its Climatic Effects Group State Key Laboratory of Tibetan Plateau Earth SystemEnvironment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China College of Atmospheric Science Lanzhou UniversityLanzhou 730000China National Observation and Research Station for Qomolongma Special Atmospheric Processes and Environmental Changes Dingri 858200China Kathmandu Center of Research and Education Chinese Academy of SciencesBeijing 100101China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of SciencesIslamabad 45320Pakista

Given Nepal's vulnerability to extreme precipitation(EP),it is imperative to conduct a comprehensive analysis to comprehend the historical trends of such ***,acquiring precise precipitation data for EP remains challenging in mountainous countries like Nepal owing to the scarcity of densely gauged *** limitation impedes the dissemination of knowledge pertaining to EP variability events in *** current research on this topic is deficient for two main reasons:1)there is a lack of studies leveraging recently released high-resolution precipitation products to identify their EP detection capabilities,which further hinders the usability of those products in data-scarce regions like Nepal,and 2)most studies have focused on the characterisation of EP events in Nepal rather than their spatial and temporal *** address these issues,this study evaluated the EP detection capabilities of four high-resolution precipitation product datasets(PPDs)across Nepal from 1985 to *** datasets include the ERA5 Land reanalysis data,satellite-based precipitation data(PERSIANN_CCS_CDR and CHIRPS_V2.0)and a merged dataset(TPHiPr).We used various statistical and categorical indices to assess their ability to capture the spatial and temporal variability of EP *** annual EP events were characterised by 11 indices divided into frequency and intensity *** TPHiPr merged dataset offered a robust depiction of monthly precipitation estimates,achieving the highest critical success index,accuracy,probability of detection and a low false alarm ratio for daily precipitation detection of 0.1 mm in ***,the PERSIANN_CCS_CDR dataset exhibited poor *** PPDs showed increasing trends in EP ***,the TPHiPr dataset showcased those trends with fewer errors and stronger correlations for many frequency(R10mm,R20mm and R25mm)and intensity(RX1day,RX5day,PRCPTOT and R99p)*** results indicate that TPHiPr outperformed ot

关键词： Extreme precipitation Precipitation product Nepal TPHiPr ERA5 land PERSIANN_CCS_CDR CHIRPS_V2.0

Reduction of die roll height in duplex gears through a sheet-bulk metal forming method

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Advances in Manufacturing 2019年第1期7卷 42-51页

作者： Xiao-Long Sun Xin-cun Zhuang feng-Chun Yang Zhen Zhao Institute of Forming Technology and Equipment School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai 200030 People's Republic of China National Engineering Research Center of Die & Mold CAD Shanghai Jiao Tong University Shanghai 200030 People's Republic of China

In the existing shearing processes for fabricating parts such as duplex gears, die roll is difficult to avoid. Accordingly, a method based on sheet-bulk metal forming for fabricating a duplex gear with extremely small die roll in one stroke is proposed in the current work. The process could be divided into three stages according to the forming features: upsetting and shearing stage, lateral extrusion stage, and local filling stage. The die roll appeared in the shearing stage, which could be reduced in the subsequent extrusion and local filling stages. To reveal the underground mechanism, material flows under two situations, as a key factor to influence the forming quality, were compared and investigated. The results revealed that by controlling material flow, one could avoid the defects and reduce the die roll.

关键词： Die roll Duplex gear part Sheet-bulk metal forming Lateral extrusion Material flow

Numerical investigation of fluid phase momentum transfer in carbonate acidizing

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Petroleum Science 2022年第2期19卷 639-650页

作者： cun-Qi Jia Kamy Sepehrnoori Hai-Yang Zhang Yong-Fei Yang Jun yao School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Hildebrand Department of Petroleum and Geosystems Engineering The University of Texas at AustinAustinTX78705USA Petroleum Department Khalifa University127788Abu DhabiUnited Arab Emirates

This work mainly studies the effect of fluid phase momentum transfer mechanisms on the acidizing results,including the retardation effect of the porous structure and the interaction between the fluid phase,such as viscous dissipation and inertial *** results show that the acid fluid momentum transfer is influenced by the complex porous structure and fluid viscous ***,the Stokes-Darcy equation is recommended to be adopted to describe the fluid phase momentum transfer in the following numerical simulation studies of the carbonate acidizing *** on this model,a parametric research is carried out to investigate the impact of acid on rock physical characteristics in the stimulation *** the acid concentration appears to minimize the quantity of acid consumed for the *** acid surface reaction rate has a considerable impact on the pore volume to breakthrough and the optimum acid injection *** influence of permeability on the acidizing results basically shows a negative correlation with the injection *** difference between the acidizing curves of different permeability gradually becomes insignificant with the decrease in injection *** existence of isolated fracture and vug significantly reduces acid consumption for the breakthrough.

关键词： Fluid phase momentum transfer Carbonate acidizing Continuum model Reactive flow simulation

Expression patterns and action analysis of genes associated with blood coagulation responses during rat liver regeneration

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World Journal of Gastroenterology 2006年第42期12卷 6842-6849页

作者： Li-feng Zhao Wei-Min Zhang cun-Shuan Xu Faculty of Life Science and Technology Ocean University of China Qingdao 260003 Shandong Province China College of Life Science Henan Normal University Xinxiang 453007 Henan Province China Key Laboratory for Cell Differentiation Regulation Xinxiang 453007 Henan Province China

AIM: To study the blood coagulation response after partial hepatectomy (PH) at transcriptional level. METHODS: After PH of rats, the associated genes with blood coagulation were obtained through reference to the databases, and the gene expression changes in rat regenerating liver were analyzed by the Rat Genome 230 2.0 array. RESULTS: It was found that 107 genes were associated with liver regeneration. The initially and totally expressing gene numbers occurring in initiation phase of liver regeneration (0.5-4 h after PH), G0/G1 transition (4-6 h after PH), cell proliferation (6-66 h after PH), cell differentiation and structure-function reconstruction (66-168 h after PH) were 44, 11, 58, 7 and 44, 33, 100, 71 respectively, showing that the associated genes were mainly triggered in the forepart and prophase, and worked at different phases. According to their expression similarity, these genes were classified into 5 groups: only up-, predominantly up-, only down-, predominantly down-, up- and down-regulation, involving 44, 8, 36, 13 and 6 genes, respectively, and the total times of their up- and down-regulation expression were 342 and 253, respectively, demonstrating that the number of the up-regulated genes was more than that of the down- regulated genes. Their time relevance was classified into 15 groups, showing that the cellular physiological and biochemical activities were staggered during liver regeneration. According to gene expression patterns, they were classified into 29 types, suggesting that their protein activities were diverse and complex during liver ***: The blood coagulation response is enhanced mainly in the forepart, prophase and anaphase of liver regeneration, in which the response in the forepart, prophase of liver regeneration can prevent the bleeding caused by partial hepatectomy, whereas that in the anaphase contributes to the structure-function reorganization of regenerating liver. In the process, 107 genes associated with

关键词： Partial hepatectomy Rat Genome 230 2.0 array Blood coagulation response Genes associated with liver regeneration