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1.
“Creative development” and “creativity” have become important topics in the field of education research. The assessment of creativity is a key to understanding how instructional strategies influences the creative process and the output of learners. At present, most methods of assessing creativity are paper-and-pencil tests scored by individuals. Despite the professional training of evaluators, subjectivity in scoring assessments remains inevitable. Therefore, a completely objective tool of measurement is crucial for the progress of education to eliminate the subjectivity in manual grading. This paper presents at first place a review of the literature related to the development of creativity, the assessment of creativity, and further on the means of measuring creativity, particularly in a digital game environment. Our focus is on the application of computing technologies for the assessment of creativity, while exploring the possibility of using computerized systems such as fuzzy logic and hybrid methods to produce objective measurement results. The results of Pearson correlation coefficient between the fuzzy inference scores and the Williams CAP scores is 0.805, which shows the strong construct validity. Additionally, the fuzzy inference system can eliminate subjectivity in scoring and provide analysis results to enhance creativity, unlike paper-and-pencil scores provided without explanations.  相似文献   
2.
We consider a class of stochastic Nash equilibrium problems (SNEP). Under some mild conditions, we reformulate the SNEP as a stochastic mixed complementarity problem (SMCP). We apply the well-known sample average approximation (SAA) method to solve the SMCP. We further introduce a semismooth Newton method to solve the SAA problems. The comprehensive convergence analysis is given as well. In addition, we demonstrate the proposed approach on a stochastic Nash equilibrium model in the wholesale gas–oil markets.  相似文献   
3.
Gut microbiota community shift with coronary artery disease (CAD) has been reported in several limited cohorts during the past several years. However, whether the enriched or decreased microbiota taxa with CAD can be reproducible deserves further investigation and validation. In this study, 78 human subjects were recruited. Of these, 19 were diagnosed without stenosis in coronary artery (control group, referred to herein as Ctrl), 14 with stenosis less than 50% (LT50), and 45 with stenosis greater than 50% (GT50). Fecal samples were collected and DNA was extracted to perform 16S ribosomal RNA (rRNA) gene sequencing. The operational taxonomic units (OTUs) were analyzed to identify taxa specific to different groups; next, multivariate logistic regression was employed to test whether the defined taxa could independently predict CAD risk. We found that Deltaproteobacteria, Fusobacterium, Bilophila, Actinomyces, and Clostridium XIX were enriched in Ctrl; Prevotellaceae, Parabacteriodes, and Butyricicoccus were enriched in LT50; and Roseburia and Butyricimonas were enriched in GT50. Further analysis revealed that increased populations of Deltaproteobacteria, Fusobacterium, Bilophila, and Desulfovibrionaceae were associated with a 0.26-fold, 0.21-fold, 0.18-fold, and 0.26-fold decreased risk of CAD, respectively (p < 0.05), and an increased Prevotellaceae population was associated with a 5.63-fold increased risk of CAD (p < 0.01). A combination of the 20 microbial taxa achieved an area under the receiver operating characteristic (ROC) curve of higher than 0.88 for all discriminations between LT50 vs Ctrl, GT50 vs Ctrl, LT50 + GT50 vs Ctrl, and GT50 vs Ctrl + LT50. However, the microbial taxa previously reported as enriched in CAD patients or healthy controls could not be observed in our cohort except for Bacteroides. In conclusion, CAD patients showed a different microbial taxa signature than the healthy controls. However, the non-reproducibility of the microbiota taxa enriched in CAD across different cohorts limits the use of this signature in early diagnosis and prevention. Only decreased Bacteroides abundance was found to be a reliable marker to indicate CAD progression.  相似文献   
4.
蔡瑞初  谢伟浩  郝志峰  王丽娟  温雯 《软件学报》2015,26(11):2884-2896
如何在人群密度大、变化快、存在大量遮挡的密集场景中实现可靠的人群事件检测,是领域研究的难点和热点.在密集场景时空建模的基础上提出了一种基于多尺度时间递归神经网络的人群异常事件检测和定位方法.首先对人群场景进行网格化划分,并利用多尺度光流直方图对每个网格的人群动态进行刻画;然后,连接各个局部的人群动态获得整体的人群动态,实现整体人群动态的时间序列建模;最后,利用多尺度时间递归神经网络实现异常事件的检测和定位.其中,多尺度隐含层实现了密集场景中不同规模相邻网格之间的空间联系,节点间的反馈关系则为时间维度上的关系表达提供了有效方案.与多种代表性算法的对比实验,验证了本方法的有效性.  相似文献   
5.
主要对室内定位技术展开研究,首先通过手持智能设备收集指定范围样本点的坐标及wifi热点信息;然后应用位置指纹定位方法进行绝对定位;为了提高行走过程中定位的准确性和实时性,采用行人航迹推算算法,即通过手机传感器采集并经处理的数据进行步频检测、步长估算和方向检测,实现相对位置变化的估算.行人航迹算法克服位置指纹定位的不稳定性,而位置指纹定位算法及时调整行人航迹算法带来的累积误差.实验结果表明两种室内定位技术的结合有效提高了室内定位的准确性,能充分应用到实际生活中.  相似文献   
6.
The evaporative heat transfer of the non-boiling annular two-phase flow of air-water in a small vertical tube with uniform wall heat flux was studied both theoretically and experimentally. A simplified two-phase flow boundary layer model was used to calculate the thickness of the water film attached to the wall, and from the liquid film thickness the evaporative heat transfer coefficients of the annular two-phase flow were obtained. Theoretical equations and semi-theoretical equations were proposed for predicting the evaporative heat transfer of the annular two-phase flow of air-water in a small vertical tube. The semi-theoretical prediction agrees well with the experimental data. The mechanism of the heat transfer enhancement is the evaporation of the thin liquid film attached on the wall.  相似文献   
7.
A gradient-domain-based edge-preserving sharpen filter   总被引:1,自引:0,他引:1  
As one of the most fundamental operations in computer graphics and computer vision, sharpness enhancement can enhance an image in respect of sharpness characteristics. Unfortunately, the prevalent methods often fail to eliminate image noise, unrealistic details, or incoherent enhancement. In this paper, we propose a new sharpness enhancement approach that can boost the sharpness characteristics of an image effectively with affinity-based edge preserving. Our approach includes three gradient-domain operations: sharpness saliency representation, affinity-based gradient transformation, and gradient-domain image reconstruction. Moreover, we also propose an evaluation method based on sharpness distribution for analyzing all sharpness enhancement approaches in respect of sharpness characteristics. By evaluating the sharpness distribution and comparing the visual appearance, we demonstrate the effectiveness of our sharpness enhancement approach.  相似文献   
8.
Bulletin of Engineering Geology and the Environment - This paper presents a review on the land subsidence caused by groundwater withdrawal in Xi’an, China. With the increasing demands of...  相似文献   
9.
Anatase titanium(Ⅳ) oxide(TiO_2) particles with exposed {001} and {101} facets were prepared by hydrothermal treatment of amorphous TiO_2 with H_2O_2-NH_3 solution. Crystal phase, shape, and size of TiO_2 particles are found to be greatly dependent on the ratio of H_2O_2-NH_3 solution. The prepared TiO_2 particles with specific exposed crystal faces show higher photocatalytic activity for acetaldehyde decomposition than commercial spherical TiO_2 particles. This result implies that recombination is prevented by spatial separation of redox sites in the particles because of selective migration of electrons and positive holes to specific exposed crystal faces and/or different reactivity of electrons and positive holes on the specific exposed crystal face.  相似文献   
10.
Existing standards show a clear discrepancy in the specification of the maximum proton energy for qualified ground-based evaluation of single-event effects,which can range from 180 to 500 MeV. This work finds that the threshold linear energy transfer of a tested device is a critical parameter for determining the maximum proton energy. The inner mechanisms are further revealed. Highenergy deposition events(10 MeV) in sensitive volumes are attributed to the interaction between protons and the tungsten vias in the metallization layers.  相似文献   
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