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大学生“要分”现象透视 被引量:1
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作者 成跃 《山西高等学校社会科学学报》 2012年第1期95-98,共4页
目前,不少高校大学生要分现象有愈演愈烈之势。在要分现象的影响下,原先的价值标准、价值刚性变得可以变通协商,对高校的教学、管理和大学生的成长都产生了极大的负面影响。大学生要分行为的产生,既有大学生主观方面的原因,也有单位、... 目前,不少高校大学生要分现象有愈演愈烈之势。在要分现象的影响下,原先的价值标准、价值刚性变得可以变通协商,对高校的教学、管理和大学生的成长都产生了极大的负面影响。大学生要分行为的产生,既有大学生主观方面的原因,也有单位、家庭和社会客观因素的影响。学校应加强道德建设、制度建设,改革考试方式,建立科学的评优体系,以维护校纪、校规和校风,还神圣教育殿堂之清名。 展开更多
关键词 考试 大学生 要分 改革
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浅析当代大学生“跑分要分”现象
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作者 沈杨 《河南科技》 2013年第12X期260-260,共1页
当今社会"跑分要分"现象在大学里日益盛行,更有甚者已经成为某些在校大学生的"必修课"。这种现象的出现,有违高校倡导的道德准则,遏制此种乱象,不仅是对广大学生负责,也有利于高校严肃校风校记和社会道德风尚的塑造。
关键词 要分 学术诚信
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大学校园期末考试“要分”现象浅析
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作者 李乃舒 《青年与社会》 2014年第2期204-204,共1页
“要分”现象在大学校园中悄然开始。这种现象不仅损害了校园的纯洁性,影响学生的学习心理,还挫伤了教师的教学热情。文章尝试通过历史考查分析现象产生的原因、并指出该现象带来的危害,最后从教师的角度提出了三点解决方案。
关键词 要分 教学事故 知识传递
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桔皮油中与发泡聚苯乙烯塑料相溶组分的分析 被引量:4
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作者 张秋芬 胡治元 张秀华 《洛阳工业高等专科学校学报》 2003年第2期4-4,54,共2页
气相色谱法测定结果表明:桔皮提取物中有一绝对优势组分。通过红外光谱和核磁共振进一步协同确定,与聚苯乙烯具有良好相溶性的组分是(d)-柠烯,即d-limonene。
关键词 桔皮油 发泡聚苯乙烯塑料 相溶性 气相色谱法 红外光谱 核磁共振 (d)-柠烯 d-1imonene 废物处理 生物降解
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高校学生成绩评定过程中存在的问题及对策
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作者 郑华 杜宇能 乔向兵 《科教导刊》 2015年第11Z期165-167,共3页
目前,不少大学大学生要分现象比较普遍。审视大学生的要分现象,更多老师持否定态度,但仔细分析大学生要分的原因,也有大学和老师的因素。大学在市场经济条件下,在每年都会碰到"最难就业年"的就业背景下,在不同大学大学生出国... 目前,不少大学大学生要分现象比较普遍。审视大学生的要分现象,更多老师持否定态度,但仔细分析大学生要分的原因,也有大学和老师的因素。大学在市场经济条件下,在每年都会碰到"最难就业年"的就业背景下,在不同大学大学生出国留学的歧视性待遇的情况下,如何更好地把控学生培养标准,满足学生校外竞争的合理诉求,并且制定对策,更好地体现大学的以人为本的理念,是当下大学与时俱进应当考虑的一个重要课题。 展开更多
关键词 考试 大学生 要分 对策
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Study on Plant Landscape Design of Urban Comprehensive Park 被引量:3
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作者 胡牮 华鑫娜 颜玉娟 《Agricultural Science & Technology》 CAS 2017年第12期2563-2566,共4页
The urban comprehensive park is the main body of the urban environment construction, and the plant landscape is the most important landscape element of the comprehensive park. It is helpful for the landscape design of... The urban comprehensive park is the main body of the urban environment construction, and the plant landscape is the most important landscape element of the comprehensive park. It is helpful for the landscape design of the comprehensive park to improve the environmental quality and the sustainable development of the city. Taking the "Nanjiang Park" in Xiaoshan District of Hangzhou as the research object, the landscape design of plants was explored and analyzed. The results showed that there were significant differences in the application forms of plant land- scapes in different functional zones in comprehensive parks. The specific forms of the garden elements had different needs of plant landscape construction. According to the results of case studies, it found that comprehensive parks could improve the functions, create the aesthetic sense, enhance the atmosphere and enhance the taste through plant landscape design. In addition, corresponding suggestions were put forward according to the current situation with the aim to provide references for the future plant landscape design related with garden greens. 展开更多
关键词 Plant landscape Comprehensive park Function zoning Landscape ele-ments Optimization analysis
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Feature combination via importance-inhibition analysis
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作者 杨思春 高超 +2 位作者 姚佳岷 戴新宇 陈家骏 《Journal of Southeast University(English Edition)》 EI CAS 2013年第1期22-26,共5页
A new method for combining features via importance-inhibition analysis (IIA) is described to obtain more effective feature combination in learning question classification. Features are combined based on the inhibiti... A new method for combining features via importance-inhibition analysis (IIA) is described to obtain more effective feature combination in learning question classification. Features are combined based on the inhibition among features as well as the importance of individual features. Experimental results on the Chinese questions set show that, the IIA method shows a gradual increase in average and maximum accuracies at all feature combinations, and achieves great improvement over the importance analysis(IA) method on the whole. Moreover, the IIA method achieves the same highest accuracy as the one by the exhaustive method, and further improves the performance of question classification. 展开更多
关键词 question answering system questionclassification feature combination importance-inhibitionanalysis
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Agricultural Development of Nanjing Suburban Counties based on Contribution Models of Production Factors
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作者 李响 张琤琤 +1 位作者 李睿婷 许才明 《Agricultural Science & Technology》 CAS 2012年第12期2663-2666,共4页
According to data in Nanjing Statistical Yearbook, contribution made by agricultural production factors was analyzed with contribution models of agricultural factors and the results showed that with restriction of lab... According to data in Nanjing Statistical Yearbook, contribution made by agricultural production factors was analyzed with contribution models of agricultural factors and the results showed that with restriction of labor force and land, Nanjing suburban counties have entered into a stage of "high input-high output", considering no matter from agricultural total value of output or from agricultural added value. In future, structure configuration of agricultural input factors should be optimized in Nanjing suburban counties by technology input to improve agricultural technology and technical efficiency in order to further achieve sustainable development of agriculture. 展开更多
关键词 Nanjing suburban counties Agricultural output Input factors Contribution analysis
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Plant Developmental Biology in China: Past, Present and Future 被引量:5
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作者 许智宏 种康 《Acta Botanica Sinica》 CSCD 2002年第9期1085-1095,共11页
Plant development is a process from germination of seed to vegetative growth, flower initiation and development, fertilization and finally to the next generation seed formation. A lot of achievements have been obtai... Plant development is a process from germination of seed to vegetative growth, flower initiation and development, fertilization and finally to the next generation seed formation. A lot of achievements have been obtained in plant developmental biology in China. Since the 1990's, those young generation scientists returned to China from abroad to use molecular and genetic techniques to study morphological, physiological and biochemical process of plant development. The present paper reviews the progress in some research area of plant developmental biology in the past decades and also prospects the chance and future of plant developmental studies, due to the recent advances of plant genome sequencing and functional genomics in China under the international research background. 展开更多
关键词 developmental biology organ differentiation flowering physiology sexual differentiation fertilization biology seed physiology
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The Distribution Characteristics of Soil pH Values of Tobacco-growing Areas in Dali City and Its Correlation with Soil Nutrients 被引量:1
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作者 杨春文 赵宇 +5 位作者 王新中 杨成伟 杨志娟 户艳霞 孙军伟 王德勋 《Agricultural Science & Technology》 CAS 2015年第5期951-953,972,共4页
[Objective] The aim was to study the distribution characteristics of soil pH values and its correlation with soil nutrients in tobacco-growing areas. [Method] Soil nutrients of 43 samples from tobacco-growing areas in... [Objective] The aim was to study the distribution characteristics of soil pH values and its correlation with soil nutrients in tobacco-growing areas. [Method] Soil nutrients of 43 samples from tobacco-growing areas in Dali City were analyzed.[Results] The results showed that average pH value of tobacco-planting soil in Dali City was 6.52, soil samples which suited for flue-cured tobacco cultivation accounted for 72.09% of total soil samples. In four soil types of tobacco-growing areas, the pH values in a descending order were as follows: alluvial soil〉 paddy soil 〉purple soil〉 red soil. At the altitude range of 1 780-2 200 m, soil pH values showed a gradual decreasing trend. The average contents of soil organic matters were relatively abundant and generally suited for high-quality tobacco cultivation; the average contents of soil alkali-hydrolyzable nitrogen, available phosphorus, exchangeable calcium and exchangeable magnesium were generally at medium and abundant level, however,their rations under the medium level in some tobacco-growing areas were 6.98%,11.63%, 2.33% and 4.65%, respectively; moreover, soil with lower available potassium contents occupied a large proportion, namely 58.14%. [Conclusion] Soil pH values had significant correlation with exchangeable magnesium and exchangeable magnesium, however, they had no significant correlation with other soil nutrients. 展开更多
关键词 Tobacco-growing areas SOIL pH values Soil nutrients Correlation analysis
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Quasi-χ~2 Distribution and the Independence of Wishart Distribution
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作者 朱道元 赵胜利 《Journal of Southeast University(English Edition)》 EI CAS 2002年第2期173-176,共4页
In this paper, the authors generalize the definition of χ 2 distribution and introduce a quasi χ 2 distribution, and then prove several properties of it, find the necessary and sufficient conditions of i... In this paper, the authors generalize the definition of χ 2 distribution and introduce a quasi χ 2 distribution, and then prove several properties of it, find the necessary and sufficient conditions of independence about multivariate normal distributions, matrix normal distributions and two parts of the Wishart distribution. 展开更多
关键词 quasi χ 2 Wishart distribution INDEPENDENCE
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The Necessary and Sufficient Conditions for Two Kinds of Matrix Equtions Having Semipositive Subdefinite Solutions 被引量:1
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作者 何楚宁 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第4期62-68,共7页
Finding solutions of matrix equations in given set SR n×n is an active research field. Lots of investigation have done for these cases, where S are the sets of general or symmetric matrices and symmetric posit... Finding solutions of matrix equations in given set SR n×n is an active research field. Lots of investigation have done for these cases, where S are the sets of general or symmetric matrices and symmetric positive definite or sysmmetric semiposite definite matrices respectively . Recently, however, attentions are been paying to the situation for S to be the set of general(semi) positive definite matrices(called as semipositive subdefinite matrices below) . In this paper the necessary and sufficient conditions for the following two kinds of matrix equations having semipositive, subdefinite solutions are obtained. General solutions and symmetric solutions of the equations (Ⅰ) and (Ⅱ) have been considered in in detail. 展开更多
关键词 semipositive subdefinite symmetric semipositie definite generalized singualr value decomposition
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Influence of brittleness and confining stress on rock cuttability based on rock indentation tests 被引量:6
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作者 WANG Shao-feng TANG Yu WANG Shan-yong 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第9期2786-2800,共15页
In order to understand the influence of brittleness and confining stress on rock cuttability,the indentation tests were carried out by a conical pick on the four types of rocks.Then,the experimental results were utili... In order to understand the influence of brittleness and confining stress on rock cuttability,the indentation tests were carried out by a conical pick on the four types of rocks.Then,the experimental results were utilized to take regression analysis.The eight sets of normalized regression models were established for reflecting the relationships of peak indentation force(PIF)and specific energy(SE)with brittleness index and uniaxial confining stress.The regression analyses present that these regression models have good prediction performance.The regressive results indicate that brittleness indices and uniaxial confining stress conditions have non-linear effects on the rock cuttability that is determined by PIF and SE.Finally,the multilayer perceptual neural network was used to measure the importance weights of brittleness index and uniaxial confining stress upon the influence for rock cuttability.The results indicate that the uniaxial confining stress is more significant than brittleness index for influencing the rock cuttability. 展开更多
关键词 rock cuttability brittleness index uniaxial confining pressures regression analysis multilayer perceptual neural network importance analysis
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Multivariate Statistical Process Monitoring of an Industrial Polypropylene Catalyzer Reactor with Component Analysis and Kernel Density Estimation 被引量:16
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作者 熊丽 梁军 钱积新 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第4期524-532,共9页
Abstract Data-driven tools, such as principal component analysis (PCA) and independent component analysis (ICA) have been applied to different benchmarks as process monitoring methods. The difference between the t... Abstract Data-driven tools, such as principal component analysis (PCA) and independent component analysis (ICA) have been applied to different benchmarks as process monitoring methods. The difference between the two methods is that the components of PCA are still dependent while ICA has no orthogonality constraint and its latentvariables are independent. Process monitoring with PCA often supposes that process data or principal components is Gaussian distribution. However, this kind of constraint cannot be satisfied by several practical processes. To ex-tend the use of PCA, a nonparametric method is added to PCA to overcome the difficulty, and kernel density estimation (KDE) is rather a good choice. Though ICA is based on non-Gaussian distribution intormation, .KDE can help in the close monitoring of the data. Methods, such as PCA, ICA, PCA.with .KDE(KPCA), and ICA with KDE,(KICA), are demonstrated and. compared by applying them to a practical industnal Spheripol craft polypropylene catalyzer reactor instead of a laboratory emulator. 展开更多
关键词 multivariate statistical process monitoring principal comPonent analysis kermel density estimation POLYPROPYLENE catalyzer reactor fault detection data-driven tools
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APPLICATION OF ADVECTIVE VORTICITY EQUATION TO TYPHOON FUNG-WONG 被引量:1
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作者 周玉淑 朱科锋 刘黎平 《Journal of Tropical Meteorology》 SCIE 2010年第2期134-142,共9页
The momentum advection vorticity equation in the form of cross multiplication is introduced, in which the divergence term in the classic vorticity equation does not appear explicitly. This equation includes the rotati... The momentum advection vorticity equation in the form of cross multiplication is introduced, in which the divergence term in the classic vorticity equation does not appear explicitly. This equation includes the rotation effect of the horizontal wind advection, which are not explicitly included in the classic vortieity equation. The vorticity and its tendency of Typhoon Fung-Wong (0808) that occurred in July 2008 are analyzed. The computed results show that the rotation effect of the advection of the horizontal wind is a leading factor in determining the change of vertical vorticity for Fung-Wong during its life cycle, especially in the period leading up to landfall. The advection term represents the tendency variation of the vertical vortieity, and the positive-value region of the vertical vorticity tendency is almost in accord with the track of Fung-Wong, which may be taken as a factor to locate the key observational region of Fung-Wong. The equation provides a supplementary diagnostic tool for the systems related with strong advection of horizontal wind. 展开更多
关键词 advection vorticity equation synoptic analysis
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Analysis of pH Value and Primary Nutrients in Blueberry Garden Soil
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作者 董克锋 刘方春 +1 位作者 姜惠铁 崔兴国 《Agricultural Science & Technology》 CAS 2016年第4期1028-1032,共5页
In order to explore the soil nutrient characteristics and put forward the improvement measures, a field experiment was arranged and performed. The experiment was conducted to evaluate the pH value and primary nutrient... In order to explore the soil nutrient characteristics and put forward the improvement measures, a field experiment was arranged and performed. The experiment was conducted to evaluate the pH value and primary nutrient status in blueberry garden soil by means of collecting 21 soil samples from the main production base of blueberries in Qingdao, according to the specific requirements of blueberries for soil pH and organic matter and the second national soil survey nutrient classification standard. Results showed that the blueberry garden soil had the following characteristics: acidic soil, low organic matter content with significant differences among different bases, moderate total nitrogen and alkaline hydrolysis nitrogen contents, high available phosphorus content and above moderate available potassium content. Then, it is found that the primary causes were the differences in soil basic fertility, excessive use of sulfur, inadequate inputs of organic matter, not thorough soil improvement, and imperfect fertilizer management in the blueberry gardens. Finally, the corresponding improvement measures were put forward, for example, increasing organic fertilizer and organic matter covering, as well as the application of CaCO_3 and formulated fertilization. 展开更多
关键词 Blueberry garden soil pH Primary nutrient Improvement measure
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A nonlinear PCA algorithm based on RBF neural networks 被引量:1
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作者 杨斌 朱仲英 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第1期101-104,共4页
Traditional PCA is a linear method, but most engineering problems are nonlinear. Using the linear PCA in nonlinear problems may bring distorted and misleading results. Therefore, an approach of nonlinear principal com... Traditional PCA is a linear method, but most engineering problems are nonlinear. Using the linear PCA in nonlinear problems may bring distorted and misleading results. Therefore, an approach of nonlinear principal component analysis (NLPCA) using radial basis function (RBF) neural network is developed in this paper. The orthogonal least squares (OLS) algorithm is used to train the RBF neural network. This method improves the training speed and prevents it from being trapped in local optimization. Results of two experiments show that this NLPCA method can effectively capture nonlinear correlation of nonlinear complex data, and improve the precision of the classification and the prediction. 展开更多
关键词 Principal Component Analysis (PCA) Nonlinear PCA (NLPCA) Radial Basis Function (RBF) neural network Orthogonal Least Squares (OLS)
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On the Smarandache Pseudo Number Sequence 被引量:7
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作者 LIU Yah-hi 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第4期581-584,共4页
The main purpose of this paper is to study the mean value properties of thesecond Smarandache pseudo-odd number sequence and pseudo-even number sequence, andgive some interesting asymptotic formula for them.
关键词 pseudo-odd numbers pseudo-even numbers asymptotic formula.
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Fault detection method with PCA and LDA and its application to induction motor 被引量:3
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作者 JUNG D Y LEE S M +2 位作者 王洪梅 KIM J H LEE S H 《Journal of Central South University》 SCIE EI CAS 2010年第6期1238-1242,共5页
A feature extraction and fusion algorithm was constructed by combining principal component analysis(PCA) and linear discriminant analysis(LDA) to detect a fault state of the induction motor.After yielding a feature ve... A feature extraction and fusion algorithm was constructed by combining principal component analysis(PCA) and linear discriminant analysis(LDA) to detect a fault state of the induction motor.After yielding a feature vector with PCA and LDA from current signal that was measured by an experiment,the reference data were used to produce matching values.In a diagnostic step,two matching values that were obtained by PCA and LDA,respectively,were combined by probability model,and a faulted signal was finally diagnosed.As the proposed diagnosis algorithm brings only merits of PCA and LDA into relief,it shows excellent performance under the noisy environment.The simulation was executed under various noisy conditions in order to demonstrate the suitability of the proposed algorithm and showed more excellent performance than the case just using conventional PCA or LDA. 展开更多
关键词 principal component analysis (PCA) linear discriminant analysis (LDA) induction motor fault diagnosis fusionalgorithm
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An equivalent finite element method to kinetics analysis of complex mechanism 被引量:8
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作者 车仁炜 陆念力 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第2期197-200,共4页
The Finite Element Method was combined with the results from considerable analysis, producing a new kinetics analysis method of EFEM for a mechanism in truss, geared system, and assembled system. The equivalent princi... The Finite Element Method was combined with the results from considerable analysis, producing a new kinetics analysis method of EFEM for a mechanism in truss, geared system, and assembled system. The equivalent principle and the motive differential equation of the system were derived by using an equivalent element, a virtual inertia matrix, and a systematic force matrix. The element’s mass matrix expression in the two dimensional and three dimensional mechanisms of the equivalent element was determined. The equivalent mass matrixes fashion of the Jacobin matrix, generalized coordinate matrix, and equivalent forces matrix were also determined. It was validated by two examples that the new method was normal, simple and direct, and had a higher efficiency than alternative methods; this is regardless of whether traditional methods are used with differential equations and calculated by using a computer. 展开更多
关键词 assembled system equivalent element equivalent system EFEM
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