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1.
朴素贝叶斯是一种处理分类问题的常用方法,但它的属性条件独立性假设在实际应用中难以成立,导致其分类性能降低。针对这一问题,文章提出了基于改进PCA的朴素贝叶斯分类算法,该算法通过Pearson和Kendall系数计算出属性间的相关性大小,基于主成分分析筛选出新的属性集,使其尽量满足条件独立性假设,并对新数据集进行朴素贝叶斯分类。实验结果表明,该方法有效地提高了分类准确率。  相似文献   
2.
鲁迅与穆时英笔下都塑造过一系列具有丑角特质的形象。不同的是,穆时英笔下的丑角具有自觉性,以小丑身份为面具,掩盖自己的孤独与恐惧;鲁迅笔下的丑角多是非自觉的,他们认真地践行着自己的人生理念,却因其与周遭环境格格不入,被人当作小丑、疯子。从中折射出两位作家迥异的生命观,穆时英从个体角度出发,写出了都市人在悲哀的脸上戴了快乐面具的无奈,对丑角表演持拥抱态度;鲁迅则从批判国民性的宏观角度出发,敏锐地意识到了丑角表演背后的隐忧,对其持拒斥的姿态。  相似文献   
3.
布罗代尔认为,理想的历史应该是多声部的。现代意义上的口述史的出现使基于文献书写的历史的单声部特征显露无遗。口述史不再是现代社会“沉默的大多数”发出的声音。以口头陈述为基础的口述史的叙事和以文献为基础的历史的书写都同样是有关历史事实的观念的反映。各具独立旋律的叙事与书写理应建立起和谐的关系而形成复调历史。这种复调历史并非杜赞奇基于话语分析方法,以解构民族国家单线叙事为目的的复线历史。口述史与历史二者之间互补互益的差异使反思性知识与批判性知识可以对过去的历史进行检讨并对历史事实进行更为深刻的理解。借鉴历史研究方法及滥觞于研究无文字民族的民族志方法是解决口述史实践中存在的诸多问题的重要路径。  相似文献   
4.
Porter and Kramer’s concept of creating shared value (CSV) has been welcomed as an approach to corporate social responsibility (CSR) among corporations that also provides a practical opportunity for dialogue in public relations, but it has been little examined from the general population’s (i.e., the public’s) perspective. Such scrutiny is important because its findings enable public relations to contribute to the debate and development of CSV from both the public’s and the organization’s viewpoints. Additionally, if public relations professionals understand how the public perceives CSV, they can give a strategic perspective to top management for maximizing moral capabilities of the business and formulate effective communication to promote CSV initiatives. This study investigates whether the public prefers corporations to practice CSV as opposed to intrinsic CSR as a separate pursuit from business interests. It also explores the role of leadership as an influential and ethical construct in implementing effective CSV as perceived by the public. The public’s preference for CSV over intrinsic CSR was revealed in a survey of 1784 participants in the United States (US), Germany, and China. Factor analysis results further suggested that effective CSV competencies of CEOs were construed as a unidimensional concept in the US, but German and Chinese participants viewed it as two-dimensional. The public perceived that leaders’ moral character played a more important, core role in effective CSV than did altruistic and behavioral attributes, across nations. Network analysis of the perceived effective CSV-characteristics provides further implications for CSV communication.  相似文献   
5.
6.
Objective: To compare anthropometric measures of body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), and sagittal abdominal diameter (SAD) as predictors of blood pressure in college students. Participants: Students (N = 116) were recruited from November 2012 to May 2014 at an urban university and rural community colleges. Methods: Students underwent a brief physical examination during which anthropometric measures were obtained and blood pressure was measured. Covariates were measured using self-reported questionnaires. Hierarchical multiple linear regressions were used for the data analysis. Results: All anthropometric measures were predictive of systolic (SBP) and diastolic blood pressure (DBP). WC was the strongest predictor of SBP (β = .582, p < .01) explaining an additional 3–4% of the variance than BMI, WHtR, or SAD. The measures were similar in predicting DBP. WC predicted SBP independent of BMI. Conclusions: Clinicians should consider using WC to assess the risk for hypertension in college students.  相似文献   
7.
Abstract

Risk and performance management are at the core of complex bespoke systems (CBSs). CBSs are developed to customer–specified requirements in terms of structure, functionality and conformance. This article examines how risk and performance management are integrated as essential systems in the successful development of projects across multi-organizational functions in complex bespoke system (CBS) organizations. The article argues for the development of a quality management system that consists of two sub-processes: quality control and quality development. Using three case studies from engineering companies, we provide evidence and insights of the way change control, quality development and quality performance are developed in innovating business solutions.  相似文献   
8.
《Risk analysis》2018,38(8):1634-1655
The work in the article presents the development of an application guide based on feedback and comments stemming from various railway actors on their practices of SIL allocation to railway safety‐related functions. The initial generic methodology for SIL allocation has been updated to be applied to railway rolling stock safety‐related functions in order to solve the SIL concept application issues. Various actors dealing with railway SIL allocation problems are the intended target of the methodology; its principles will be summarized in this article with a focus on modifications and precisions made in order to establish a practical guide for railway safety authorities. The methodology is based on the flowchart formalism used in CSM (common safety method) European regulation. It starts with the use of quantitative safety requirements, particularly tolerable hazard rates (THR). THR apportioning rules are applied. On the one hand, the rules are related to classical logical combinations of safety‐related functions preventing hazard occurrence. On the other hand, to take into account technical conditions (last safety weak link, functional dependencies, technological complexity, etc.), specific rules implicitly used in existing practices are defined for readjusting some THR values. SIL allocation process based on apportioned and validated THR values is finally illustrated through the example of “emergency brake” subsystems. Some specific SIL allocation rules are also defined and illustrated.  相似文献   
9.
In the current investigation, idiosyncratic deals (i-deals; individualized work arrangements) are modeled as differentiated resources that shape leader-member exchange (LMX) relationships in workgroups. We integrate literature on leader-member exchange (LMX) with research on i-deals to argue that employee evaluations of i-deals received from the grantor –typically the leader- enhance employee perceptions of LMX, which in turn become instrumental in generating positive performance outcomes. Furthermore, because workgroup characteristics have potential implications on the relationship between a deal grantor and the deal recipient, drawing upon social identity theory of leadership, we reason that the i-deals-LMX relationship is affected by the overall value congruence among the group members. Cross-level moderated mediation analyses on multi source data obtained from 289 employees nested in 60 workgroups showed that the mediational role of LMX in the i-deals to performance outcomes relationship was weaker in high value congruence groups.  相似文献   
10.
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