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11.
近年来,有些院校在工业设计专业的新教学计划中提出了“课程环”的构想。这样的教学模式试图把先前自成一体的课程有机地融解在数个相对的小系统中,进而形成以课题设计为中心的大系统。而过去的“三段式”教学模式则是以各门独立课程为中心的。在“三段式”教育下,有的学生几乎每门功课都优秀却做不出好设计来,更有甚者不懂设计程序而无法完成完整的设计。这种教学模式存在诸多弊端。 相似文献
12.
Rosa Arboretti Riccardo Ceccato Luca Pegoraro Luigi Salmaso Chris Housmekerides Luca Spadoni Elisabetta Pierangelo Sara Quaggia Catherine Tveit Sebastiano Vianello 《Journal of applied statistics》2022,49(10):2674
Industrial statistics plays a major role in the areas of both quality management and innovation. However, existing methodologies must be integrated with the latest tools from the field of Artificial Intelligence. To this end, a background on the joint application of Design of Experiments (DOE) and Machine Learning (ML) methodologies in industrial settings is presented here, along with a case study from the chemical industry. A DOE study is used to collect data, and two ML models are applied to predict responses which performance show an advantage over the traditional modeling approach. Emphasis is placed on causal investigation and quantification of prediction uncertainty, as these are crucial for an assessment of the goodness and robustness of the models developed. Within the scope of the case study, the models learned can be implemented in a semi-automatic system that can assist practitioners who are inexperienced in data analysis in the process of new product development. 相似文献
13.
海报设计的竞争优势及发展趋向 总被引:3,自引:0,他引:3
朱琪颖 《江南大学学报(人文社会科学版)》2007,6(3):120-123
海报设计在长达一个多世纪的发展过程中,经历了不断的发展和演变,形成了独特的风格和特点。文章主要分析了海报在当代社会的存在状况以及竞争优势;论述了海报设计作为一种设计艺术形态,在全球一体化的社会环境中蕴涵着个人化、艺术化以及多元化的发展趋势。 相似文献
14.
李倡平 《中南林业科技大学学报(社会科学版)》2010,4(2):106-108
申报全国教育科学规划课题的关键是有一个好的选题和科学严谨的设计与论证。要正确把握和了解教育科学与教育科学规划课题的内涵,科学地辨析教育科学规划课题的学科分类,精心选择研究问题,深入透彻地做好研究现状述评;准确地界定课题的核心概念,科学地选取研究理论依据,慎重而又大胆地提出研究假设,重点设定好研究目标与研究内容;恰当地选取研究方法、研究思路与技术路线,注意阶段性和终结性成果的预设,合理地组建研究团队,讲求学术规范,才能充分体现课题设计的规范性,严谨性,科学性,创新性,为评审专家所认可。 相似文献
15.
Thomas DC 《Lifetime data analysis》2007,13(4):565-581
I consider the design of multistage sampling schemes for epidemiologic studies involving latent variable models, with surrogate
measurements of the latent variables on a subset of subjects. Such models arise in various situations: when detailed exposure
measurements are combined with variables that can be used to assign exposures to unmeasured subjects; when biomarkers are
obtained to assess an unobserved pathophysiologic process; or when additional information is to be obtained on confounding
or modifying variables. In such situations, it may be possible to stratify the subsample on data available for all subjects
in the main study, such as outcomes, exposure predictors, or geographic locations. Three circumstances where analytic calculations
of the optimal design are possible are considered: (i) when all variables are binary; (ii) when all are normally distributed;
and (iii) when the latent variable and its measurement are normally distributed, but the outcome is binary. In each of these
cases, it is often possible to considerably improve the cost efficiency of the design by appropriate selection of the sampling
fractions. More complex situations arise when the data are spatially distributed: the spatial correlation can be exploited
to improve exposure assignment for unmeasured locations using available measurements on neighboring locations; some approaches
for informative selection of the measurement sample using location and/or exposure predictor data are considered. 相似文献
16.
17.
转股条款的灵活设计是实现可转债特定融资动因的重要途径之一,本文根据相关理论假说及其对证券条款设计的意义,设计了较为系统的实证分析框架和稳健的模型估计方法,对我国可转债的转股条款进行了较为严格意义上的实证检验。研究发现,高负债率、小规模和获取经营现金能力较差的公司明显倾向于设计较低的转股价格和较高的转换比率;信用记录较短(以上市年限代表)和收益不稳定的公司具有相同的倾向。国内可转债设计主要由财务危机假说解释,而制度性因素对条款设计具有重要影响。总体上,目前可转债的条款设计没有得到发行人的理性对待,本文就此提出了相关政策建议。 相似文献
18.
Marschner IC 《Pharmaceutical statistics》2007,6(1):23-33
Clinical trials are often designed to compare several treatments with a common control arm in pairwise fashion. In this paper we study optimal designs for such studies, based on minimizing the total number of patients required to achieve a given level of power. A common approach when designing studies to compare several treatments with a control is to achieve the desired power for each individual pairwise treatment comparison. However, it is often more appropriate to characterize power in terms of the family of null hypotheses being tested, and to control the probability of rejecting all, or alternatively any, of these individual hypotheses. While all approaches lead to unbalanced designs with more patients allocated to the control arm, it is found that the optimal design and required number of patients can vary substantially depending on the chosen characterization of power. The methods make allowance for both continuous and binary outcomes and are illustrated with reference to two clinical trials, one involving multiple doses compared to placebo and the other involving combination therapy compared to mono-therapies. In one example a 55% reduction in sample size is achieved through an optimal design combined with the appropriate characterization of power. 相似文献
19.
When we want to compare two designs we usually assume the standard linear model with uncorrelated observations. In this paper we use the comparison method proposed by Ghosh & Shen (2006) to compare three level orthogonal arrays with 18, 27 and 36 runs under a possible presence of correlation in observations. 相似文献
20.
论述了互连网络拓扑优化设计问题,建立了必要的数学模型,该数学模型是一个非线性组合优化问题,它属于NP—完备类问题。采取拉格朗日松弛法、次梯度迭代算法和启发式算法,得出最优下确界和结论。 相似文献