一种改进的基于峭度指标的FastICA算法     

孟令博  耿修瑞  杨炜暾 《中国科学院大学学报》2019,36(3):410-416

基于峭度指标的FastICA算法具有较快的收敛速度和较高的计算效率，被广泛应用于多光谱图像的特征提取。经典的FastICA算法基于固定点迭代法得到图像的各个独立成分，在迭代过程中，每一个独立成分的求解都需要所有像元的参与。因此，当数据量较大或图像中像元较多时，FastICA的计算量很大，此时它的速度优势就会大打折扣。遥感数据一般都具有较大的尺寸，因此如何将FastICA直接应用于遥感数据，是一个具有实际意义的问题。通过引入多光谱图像协峭度张量的概念，将FastICA的固定点迭代问题转化为代数形式的张量计算，避免每次迭代过程中需所有像元参与的缺陷，因而大大降低计算复杂度。多光谱图像实验结果表明，该算法明显快于传统的基于峭度指标的FastICA算法。  相似文献   

基于“立德树人”的我国青少年体育品德评价指标体系构建研究     

汤利军  蔡皓 《武汉体育学院学报》2019,53(10):75-80

运用文献资料法、问卷调查法、德尔菲法、层次分析法等研究方法，以人的全面发展理论、马斯洛的需要层次理论、道德认知发展心理学理论为基础，以国家出台的各类关于学生道德、品德发展的文件、中小学生手册和奥林匹克精神等为依据，构建出青少年体育品德评价指标体系。指标体系包括体育精神、体育品格、体育道德行为3个一级指标，爱国主义精神、集体主义精神、竞争开拓精神、拼搏进取精神、团队合作精神、创新精神、法制精神、爱、志、信、义、体育道德意应能力、体育道德创造能力和体育道德自我教育能力14个二级指标，并采用层次分析法分析出各指标的权重。青少年体育品德评价指标体系具有一定的科学性、适用性及操作性。  相似文献   

网络舆情衍进指数构建与实证分析   总被引：1，自引：0，他引：1  

黄微  朱镇远  许烨婧  孙悦 《图书情报工作》2019,63(20):26-33

[目的/意义]提出和构建网络舆情衍进指数，以描述网络舆情演化过程中常衍生出新的子话题的现象，对于舆情预警、预测具有重要的理论及实践意义。[方法/过程]以文本聚类结果和文本聚类有效性为依据，提出网络舆情衍进的判别标准和舆情衍进指数的构建过程，并以"教科书老赖"这一事件作为样本数据进行实证分析。[结果/结论]所构建的舆情衍进速率指数可以用于描述舆情衍进。在突发期阶段话题舆情衍进指数最高，此后逐渐下降，这一阶段的舆情衍进最为剧烈，子话题的出现呈现爆发性增长；舆情衍进指数在舆情蔓延期内出现阶梯式下降，此后保持为负值，舆情的子话题开始逐渐减少，舆情内容本身由发散转为收敛；进入消散期后，子话题数量趋于稳定。作为舆情衍进速率的测度和舆情衍进的判别方式，舆情衍进指数为舆情监管和舆情预警提供了全新的角度。  相似文献   

我国农村体育精准扶贫改革路径分析     

赵嘉磊 《广州体育学院学报》2019,(6):16-19

为了丰富户外用品上市公司的评价研究，提升企业的经营绩效，以我国户外用品6家上市公司2016年度财务数据为样本，采用熵权法从偿债能力、运营能力、盈利能力和成长能力四个纬度，对其进行了综合评价。结果显示：（1）公司经营结构中，偿债能力所占的权重最大，运营能力次之，盈利能力排名第三，成长能力所占权重最小；（2）6家公司中，4项一级指标的评分存在明显的两极分化现象。其中，三夫户外的偿债能力最强，牧高笛最弱；牧高笛的运营能力和盈利能力最突出，三夫户外的运营能力和嘉麟杰的盈利能力比较薄弱；中潜股份的成长能力最优秀，浙江永强成长能力最小；（3）综合实力强弱顺序依次为探路者、三夫户外、牧高笛、中潜股份、嘉麟杰、浙江永强。  相似文献   

2019年篮联世界杯广州赛区小组赛对中国队的启示     

崔曼峰  赵毅砥 《广州体育学院学报》2020,(1):82-85

2019年国际篮联篮球世界杯在中国圆满举行,广州作为分赛场,承接了西班牙、波多黎各、突尼斯以及伊朗四支代表队的小组比赛6场。通过对广州赛区四支队伍在小组赛中的表现技术进行分析,并对比中国队在本次赛事中的表现,发现中国男篮在备赛与参赛阶段,存在大赛目标不清晰,心理训练与细节训练不足,教练团队执教水平不稳定,篮球基本功不扎实等一系列问题,反映出我国篮球的发展正处于困境。系统地分析广州小组赛中四支队伍的赛况,并与中国队做出对比,有针对性地提出建议,为中国篮球的发展提供参考。  相似文献   

Evaluation of soccer players under the Moneyball concept     

Luiz Octávio Gavião  Annibal Parracho Sant’Anna  Gilson Brito Alves Lima  Pauli Adriano de Almada Garcia 《Journal of sports sciences》2020,38(11-12):1221-1247

ABSTRACT

The recruitment of athletes with limited resources is a global problem in professional sports. In US Major League Baseball, the experience of the Oakland Athletics’ general manager in the last decade turned his “Moneyball” model into a synonym of quantitative analysis in the transfer market of baseball players. His strategy focused on hiring players with outstanding technical skills but relatively low market value. This study adapted this model to the framework of a multiple criteria decision aid (MCDA), by selecting undervalued players who have complementary abilities. The novelty here refers to the joint use of four algorithms explored by the composition of probabilistic preferences (CPP) (i.e., ranking, classification, dynamic evaluation and regularity analysis) and their application to soccer player performance evaluation. The new model analysed the recent transfer of a left-back soccer player to Europe. The results indicated 12 opportunities for better investment, among 32 left and right-back players considered. Two years later, the value of the same player was considerably lower. He played only five matches in the 2018–2019 season, without scoring or providing any assists. On the other hand, the players better classified by the CPP-MB model presented higher performances and market values.  相似文献   

What is the Australian National Maritime Museum Ilma collection?     

Dominique Sweeney 《档案与原稿》2019,47(1):153-163

ABSTRACT

The Australian National Maritime Museum (ANMM) in their Darling Harbour warehouse store just over one thousand Ilma. The Ilma are performance symbols of Bardi law and custom, which tell stories of the lands and seas of the Dampier Peninsula, King Sound and surrounding islands of Western Australia. Ilma performances are public and meant for all to see. The ANMM in 2007 resourced detailed documentation of the collection. In 2018 the collection still does not appear on the online catalogue and remains unavailable for public view. While recent efforts have been put into the collection there are important questions to be raised about the responsibility of museums to collections that have contested meanings and serve multiple purposes.  相似文献   

基于STAR-CCM+的汽车挡风玻璃除霜性能提升的仿真分析与研究     

胡忠文 《苏州市职业大学学报》2021,(1)

采用计算流体动力学的方法,利用STAR-CCM+软件对某一车型挡风玻璃除霜性能进行数值模拟分析。通过对出风口格栅进行调整,改变了暖风气流与挡风玻璃之间碰撞角的大小与碰撞点的位置,优化了挡风玻璃表面暖风气流的分布,提升了除霜性能,为汽车除霜风道的设计和改善车辆除霜性能提供了参考。  相似文献   

The impact of socioeconomic status on parental factors in promoting academic achievement in Chinese children     

《International Journal of Educational Development》2020

Children from families of low socioeconomic status (SES) tend to experience lower academic achievement than children from middle-SES families. This discrepancy can be attributed to a range of parental factors. The present study tested: (1) the extent to which academic achievement in three core subjects differs between children from low- and middle-SES backgrounds; (2) the differences in parental expectation, parental involvement, and child engagement across the two groups; and (3) the mediating role of parental expectation, parental involvement, and child engagement in explaining how SES influences children’s academic achievement. The sample consisted of 184 primary students with low SES and 165 primary students with middle SES from mainstream primary schools in Hong Kong. Results revealed significant differences in parental expectation, parental involvement, child engagement, as well as academic achievement in Chinese and English subjects between the low-SES and middle-SES groups. Our findings also suggest that parental expectation, parental involvement, and child engagement may be important mediators in the relationship between SES and academic achievement.  相似文献   

The intermediating role of organizational culture and internal analytical knowledge between the capability of big data analytics and a firm’s performance     

《International Journal of Information Management》2020

Firms are increasingly relying on business insights obtained by deploying data analytics. Analytics-driven business decisions have thus taken a strategic imperative role for the competitive advantage of a firm to endure. The extent and effectiveness through which business firms can actually derive benefits by deploying big data-based practices requires deep analysis and calls for extensive research. This study extends the big data analytics capability (BDAC) model by examining the mediatory effects of organizational culture (CL) between internal analytical knowledge (KN) and BDAC, as well as the mediating effects of BDAC between CL and firm performance. The findings bring into focus that CL plays the role of complementary mediation between BDAC and KN to positively impact firm performance (FP); BDAC also plays a similar mediatory role between CL and the performance of a firm.  相似文献