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Predictability of Chinese Summer Extreme Rainfall Based on Arctic Sea Ice and Tropical Sea Surface Temperature

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Journal of Ocean University of China 2019年第3期18卷 626-632页

作者： zhu Zhihui HUANG Fei XIE Xiao Shanghai Marine Meteorological Center Shanghai 201306 China Key Laboratory of Physical Oceanography Ocean University of China Qingdao 266100 China Ningbo Collaborative Innovation Center of Nonlinear Harzard System of Ocean and Atmosphere Ningbo University Ningbo 315211 China

Chinese summer extreme rainfall often brings huge economic losses, so the prediction of summer extreme rainfall is necessary. This study focuses on the predictability of the leading mode of Chinese summer extreme rainfall from empirical orthogonal function(EOF) analysis. The predictors used in this study are Arctic sea ice concentration(ASIC) and regional sea surface temperature(SST) in selected optimal time periods. The most important role that Arctic sea ice(ASI) plays in the appearance of EOF1 may be strengthening the high pressure over North China, thereby preventing water vapor from going north. The contribution of SST is mainly at low latitudes and characterized by a significant cyclone anomaly over South China. The forecast models using predictor ASIC(PA), SST(PS), and the two together(PAS) are established by using data from 1980 to 2004. An independent forecast is made for the last 11 years(2005-2015). The correlation coefficient(COR) skills between the observed and cross-validation reforecast principal components(PC) of the PA, PS, and PAS models are 0.47, 0.66, and 0.76, respectively. These values indicate that SST is a major cause of Chinese summer extreme rainfall during 1980-2004. The COR skill of the PA model during the independent forecast period of 2004-2015 is 0.7, which is significantly higher than those of the PS and PAS models. Thus, the main factor influencing Chinese summer extreme rainfall in recent years has changed from low latitudes to high latitudes. The impact of ASI on Chinese summer extreme rainfall is becoming increasingly significant.

关键词： ASI summer extreme rainfall prediction

新疆生产建设兵团经济发展影响因素计量实证分析

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安徽农业科学 2009年第31期37卷 15486-15487,15508页

作者：朱辉石河子大学商学院新疆五家渠831300

以考察影响新疆生产建设兵团经济发展的因素为目的,通过对1990～2008年的相关数据进行回归分析,建立影响兵团经济增长的计量经济学模型,并在此基础上结合兵团实际有针对性地提出建议。

关键词：兵团国内生产总值回归分析多重共线性

The classification of bi-quintic parametric polynomial minimal surfaces

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Applied Mathematics(A Journal of Chinese Universities) 2017年第1期32卷 14-26页

作者： LI Cai-yun zhu Chun-gang School of Mathematics and Physics Science Dalian University of Technology Panjin 124221 China School of Mathematical Sciences Dalian University of Technology Dalian 116024 China

Parametric polynomial surface is a fundamental element in CAD systems. Since the most of the classic minimal surfaces are represented by non-parametric polynomial, it is interesting to study the minimal surfaces represented in parametric polynomial form. Recently,Ganchev presented the canonical principal parameters for minimal surfaces. The normal curvature of a minimal surface expressed in these parameters determines completely the surface up to a position in the space. Based on this result, in this paper, we study the bi-quintic isothermal minimal surfaces. According to the condition that any minimal isothermal surface is harmonic,we can acquire the relationship of some control points must satisfy. Follow up, we obtain two holomorphic functions f（z） and g（z） which give the Weierstrass representation of the minimal surface. Under the constrains that the minimal surface is bi-quintic, f（z） and g（z） can be divided into two cases. One case is that f（z） is a constant and g（z） is a quadratic polynomial, and another case is that the degree of f（z） and g（z） are 2 and 1 respectively. For these two cases,we transfer the isothermal parameter to canonical principal parameter, and then compute their normal curvatures and analyze the properties of the corresponding minimal surfaces. Moreover,we study some geometric properties of the bi-quintic harmonic surfaces based on the B′ezier representation. Finally, some numerical examples are demonstrated to verify our results.

关键词： polynomial parametric curvature canonical compute quadratic satisfy isothermal acquire verify

In-depth observations of fermentative hydrogen production from liquid swine manure using an anaerobic sequencing batch reactor

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Journal of Integrative Agriculture 2017年第6期16卷 1276-1285页

作者： Xiao Wu Jun zhu Hongjian Lin Southern Research and Outreach Center University of Minnesota MN 56093 USA Biological and Agricultural Engineering Department University of Arkansas AR 72701 USA Department of Bioproducts and Biosystems Engineering University of Minnesota MN 55108 USA

In this study,experiments were designed to reveal in-depth information of the effect of pH and hydraulic retention time（HRT）on biohydrogen fermentation from liquid swine manure supplemented with glucose using an Anaerobic Sequencing Batch Reactor（ASBR）*** values of HRT（8,12,16,20,and 24 h）were first tested and the best HRT determined was further studied at five p H levels（4.4,4.7,5.0,5.3,and 5.6）.The results showed that for HRT 24 h,there was a dividing H2 content（around 37%）related to the total biogas production rate for the ASBR System running at p H *** the H2 content went beyond 37%,an appreciable decline in biogas production rate was observed,implying that there might exist an H2 content limit in the *** other HRTs（8 through 20 h）,an average H2 content of 42%could be *** the second experiment（HRT 12 h）,the highest H2 content（35%）in the biogas was found to be associated with p H *** upswing of p H from 5.0 to 5.6 had a significantly more impact on biogas H2 content than the downswing of p H from5.0 to *** results also indicated good linear relationships of biogas and H2 production rates with HRT（r=0.9971 and0.9967,respectively）.Since the optimal ASBR operating conditions were different for the biogas/H2 production rates and the H2 yield,a compromised combination of the running parameters was determined to be HRT 12 h and pH 5.0 in order to achieve good biogas/H2 productions.

关键词： biohydrogen fermentation swine manure hydraulic retention time pH values anaerobic sequencing batch reactor

投资者情绪与上市公司投资决策——基于迎合渠道的研究

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商业经济与管理 2013年第6期 60-67,85页

作者：朱朝晖浙江工商大学财务与会计学院浙江杭州310018 浙江大学心理与行为科学系浙江杭州310028

资本市场的投资者并不完全理性,会对股票价值高估或低估,而公司管理层在投资决策时可能迎合这种错误定价。文章以2003-2010年我国上市公司为对象,证实了公司在投资决策时对投资者情绪的迎合效应,并且这种效应受到市场状况、个体投资者... 详细信息

资本市场的投资者并不完全理性,会对股票价值高估或低估,而公司管理层在投资决策时可能迎合这种错误定价。文章以2003-2010年我国上市公司为对象,证实了公司在投资决策时对投资者情绪的迎合效应,并且这种效应受到市场状况、个体投资者短视程度以及企业自身融资约束的影响。

关键词：投资者情绪迎合渠道股权融资渠道融资约束

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探索性学习、挖掘性学习和创新绩效

科学学研究 2008年第4期26卷 860-867页

作者：朱朝晖浙江工商大学浙江杭州310018

本研究基于March提出的探索性学习和挖掘性学习及其平衡理论,提出了在开放式创新模式下,两类学习的协同及其它们对创新绩效的共同促进作用,并进而分析了环境动荡性在其中的调控效应。最后,基于大样本问卷调查对假设进行了实证研究。

关键词：探索性学习挖掘性学习创新绩效环境动荡性

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英语专业博士生“研究方法论”教学探索

中国外语 2008年第4期5卷 75-76,99页

作者：朱徽四川大学

尽管博士生在硕士生阶段接受过一些专业训练,但对于研究方法、论文撰写和学术规范等仍缺乏了解。"研究方法论"课程可以帮助他们比较系统全面地了解和掌握学术研究的方法与规范。虽然英语专业博士生分属不同的研究方向,有不同的专业特征... 详细信息

尽管博士生在硕士生阶段接受过一些专业训练,但对于研究方法、论文撰写和学术规范等仍缺乏了解。"研究方法论"课程可以帮助他们比较系统全面地了解和掌握学术研究的方法与规范。虽然英语专业博士生分属不同的研究方向,有不同的专业特征,但是,他们在博士生阶段的学习研究中也存在着不少共性,这使"研究方法论"能够成为一门行之有效的博士生课程,其主要内容和教学方式也在不断实践中逐渐被师生接受。

关键词：博士生课程研究方法学术规范

Mutation on Knots and Whitney's 2-Isomorphism Theorem

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Acta Mathematica Sinica,English Series 2013年第6期29卷 1219-1230页

作者： Zhi Yun CHENG Hong zhu GAO School of Mathematical Sciences Beijing Normal UniversityLaboratory of Mathematicsand Complex SystemsMinistry of Education

Whitney＇s 2-switching theorem states that any two embeddings of a 2-connected planar graph in S2 can be connected via a sequence of simple operations, named 2-switching. In this paper, we obtain two operations on planar graphs from the view point of knot theory, which we will term ＂twisting＂ and ＂2-switching＂ respectively. With the twisting operation, we give a pure geometrical proof of Whitney＇s 2-switching theorem. As an application, we obtain some relationships between two knots which correspond to the same signed planar graph. Besides, we also give a necessary and sufficient condition to test whether a pair of reduced alternating diagrams are mutants of each other by their signed planar graphs.

关键词： Planar graph twisting 2-switching mutation

Learning Dual-Layer User Representation for Enhanced Item Recommendation

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Computers, Materials & Continua 2024年第7期80卷 949-971页

作者： Fuxi zhu Jin Xie Mohammed Alshahrani Applied Research Center of Artificial Intelligence Wuhan CollegeWuhan430212China College of Computer Science South-Central MINZU UniversityWuhan430074China Unmanned.Company Riyadh11564Saudi Arabia

User representation learning is crucial for capturing different user preferences,but it is also critical challenging because user intentions are latent and dispersed in complex and different patterns of user-generated data,and thus cannot be measured ***-based data models can learn user representations by mining latent semantics,which is beneficial to enhancing the semantic function of user ***,these technologies only extract common features in historical records and cannot represent changes in user ***,sequential feature can express the user’s interests and intentions that change time by *** the sequential recommendation results based on the user representation of the item lack the interpretability of preference *** address these issues,we propose in this paper a novel model with Dual-Layer User Representation,named DLUR,where the user’s intention is learned based on two different layer ***,the latent semantic layer adds an interactive layer based on Transformer to extract keywords and key sentences in the text and serve as a basis for *** sequence layer uses the Transformer model to encode the user’s preference intention to clarify changes in the user’s ***,this dual-layer user mode is more comprehensive than a single text mode or sequence mode and can effectually improve the performance of *** extensive experiments on five benchmark datasets demonstrate DLUR’s performance over state-of-the-art recommendation *** addition,DLUR’s ability to explain recommendation results is also demonstrated through some specific cases.

关键词： User representation latent semantic sequential feature interpretability