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821.
本文报告一种金融时间序列预测的信号分析、信息融合与智能计算组合模型,简称FEPA,由针对金融时间序列(FTS)信号分析的经验模态分解(EMD)、用于数据降维的主成分分析(PCA)和用于非线性建模的人工神经网络(ANN)三部分组成。该模型首先应用滑动窗口截取原始金融时间序列最近期数据集,应用EMD分解算法把数据集分解成不同尺度的本征模态函数(IMF),然后通过主成分分析将分解后的数据降维,提取最有信息量的特征;然后将这些特征输入到神经网络进行组合预测。本文提出的组合预测模型FEPA是基于分解-提优-合成的信息融合思想,有效提高了预测可靠性。其创新点在于:1)首次给出了EMD算法的结构化表达,提供了今后融合更多信息的算法接口;2)通过多步长预测输出深入研究EMD分解的有效信息结构;3)通过切换到更细时间框架来处理EMD的端点效应,并探索了两级时间框架下的预测效果;4)给出了金融时间序列组合预测模型的一般性架构,具有可升级性和可扩展性。并且通过滑动窗口EMD使得实证更能切近实际。通过在沪深300股指和澳大利亚股指上的实证,结果表明FEPA预测模型在沪深300股指日线和15分钟线上的预测命中率高达78%和82%,在澳大利亚股指日线上也达到了74%的命中率,经比较,明显高于文献中常见的5种模型。  相似文献   
822.
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   
823.
Africa’s developing economies remain in critical need for leadership. This paper asserts that Africa’s new growth opportunities rest with leadership that could champion organizational performance, innovativeness, and good ethics among others. A review of extant literature on leadership development programmes (LDPs) was done to examine possible initiatives that leadership developers can use to influence leadership practices in Africa. This paper proposes that in Africa, LDPs can be used to inculcate authentic leadership practices and enhance networking and acquisition of innovative skills among others. Furthermore, LDPs could target the youth considering them as an investment into tomorrow’s leadership talent pool. The paper suggests that Africa’s niche for the global highway rests in contextualization of LDPs from other regions to Africa’s unique environment.  相似文献   
824.
“翻转课堂”,即将知识传授和知识内化的顺序颠倒安排。知识传授由学生在课前自主完成,知识内化则放到课堂上实现,即从“课堂授课听讲+课后完成作业”转变为“课前自主学习+课堂协作探究”。从分析当前大学英语视听说的教学现状入手,阐述了以TBLT为基础的英语视听说翻转课堂的构建与实施,并进一步指出这种新型教学模式所带来的优势和挑战,以期为大学英语视听说教学更为合理、有效地利用翻转课堂模式提供一定的借鉴和参考。  相似文献   
825.
This article examines three novels by Ukrainian realist Ivan Franko (1856–1916): Dlia domashn'oho ohnyshcha (For the Home Hearth, 1892), Osnovy suspil'nosti (Pillars of Society, 1894), and Perekhresni stezhky (Fateful Crossroads, 1900). Previous scholars saw elements of crime fiction in these works, but the actual relationship between the two genres of crime fiction and realism has not been fully developed. By studying the conventions of crime fiction, along with its antecedent, the Gothic, and their influence on Franko, the author shows the make-up of the early Ukrainian crime fiction genre and points to its importance in understanding Franko’s vacillation between realist and modernist tendencies. As she argues, the scales of his vacillation are tipped toward modernism in its decadent form, an existential void that characterized fin de siècle Europe. Hence, Franko’s “ideal” or programmatic realism (defined by Franko as a literary style with a didactic tendency aimed at educating society), which he introduced under the appealing cover of crime and Gothic motifs, ultimately failed him. The author proposes that it is the creative modes (Gothic and crime fiction) that Franko chose for voicing his ideas about social reforms that led him, unsuspectingly, away from his programmatic goal and toward the decadent aspects of modernism.  相似文献   
826.
Social work graduate programs have long grappled with ways to attract and retain students at the intersection of race and gender. The central structure of this analysis is a hermeneutic phenomenological qualitative study on the pursuit and persistence of African-American women in graduate Social Work programs at a Historically Black Institution (HBI). The data in this article were derived from the responses of 13 participants written in their own words. The themes that emerged around the pursuit of a social work degree were (a) service to Black communities, (b) resistance to misrecognition, and (c) a seat at the table. After sharing the salient characteristics of the findings, the article opens a discussion around the significance of HBIs in educating social workers to work in urban communities and the implications for policy and practice.  相似文献   
827.
John Uwa 《Social Dynamics》2018,44(2):221-238
ABSTRACT

The culture of sewage management in Lagos dates back to pit latrines (Shalanga) in precolonial Lagos; this culture gave way to bucket latrines in the wake of British colonial administration in Lagos and then to mobile toilets in postcolonial Lagos. The introduction of bucket latrines created a new job category known as Agbepo (night-soil men) and a new material practice in the management of faecal waste among ethnicities and races inhabiting the urban space of Lagos. This material practice, I argue, created ethnic tensions and reveals the extent to which varying perceptions of sewage management determine how people perceive and relate with one another in Lagos. To validate my argument, my paper proceeds from the vantage point of the phenomenology of disgust, drawing on Chinua Achebe’s No Longer at Ease, archival materials, and selected live interviews to examine how varying perceptions of sewage management play out in the construction of relationships in Lagos.  相似文献   
828.
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   
829.
Adult Protective Services (APS) workers are exposed to substantial occupational hazards and job stress, but these stressors are underdocumented. Therefore, we sought to describe APS workers’ work environments and responses to occupational hazards and stressors, including compassion fatigue, burnout, and secondary traumatic stress. Survey data were gathered with closed-ended questionnaires administered to APS workers in an urban setting. Virtually all workers (97%) reported exposure to one or more environmental hazards in their work, and 80% reported hazard exposure in the past month. Workers also reported mixed responses to their work environment and to experiences with supervision. A sizable minority (22.7%) was at high risk for burnout, 24.6% were at risk for secondary traumatic stress, and 19.9% reported low compassion satisfaction. The results document multiple stressors in APS work. The APS partner is committed to ongoing efforts to better support its staff, and these findings can inform future efforts to enhance supervisor support and worker self-care, to minimize burnout and secondary traumatic stress.  相似文献   
830.
Despite government interest in promoting birth registration, more than a third of Indonesian children do not have a birth certificate, affecting the realisation of both their human and citizen rights. While barriers to registering children's births in Indonesia have been assessed, there is limited research on how communities perceive the importance of having a birth certificate. This study used focus group discussions to explore parental motivations around birth registration. The results of a thematic analysis found that perceived use of birth certificates, perceived control over the application process and social norms related to certificate ownership affect the intention to apply.  相似文献   
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