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The purpose of this paper is to show how pre-school children, both from Zagreb and refugees, experienced and comprehended the war during 1992. The study included 98 children from Zagreb kindergartens (pre-school nurseries). The children were asked five questions about the war in Croatia. Each was interviewed individually. A content analysis of the answers revealed that the children, in defining the warring parties and the causes of the war, besides using much information obtained through the media, based their concepts of the war on personal experience. The worst war-related experience for Zagreb children was the air-raid alarms, while the displaced or refugee children felt worst when there were bombardments, destruction and shooting—mostly personally experienced events. Generally, the children's answers suggest more mature comprehension of war than usually expected and found at the pre-school age. 相似文献
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In this paper we describe a stochastic method for global optimization based on a uniform sampling in the search domain. After a reduction of the sample, computing the distance between the remaining points and using the distribution of the kth nearest neighbour enables clusters of points to be built up, hopefully fitting the regions of attraction of significant local optima; from each of these a local search is started. The properties of the method are analysed, and detailed computational results on standard test functions are provided. 相似文献
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Nicholas Bloom Renata Lemos Raffaella Sadun Daniela Scur John Van Reenen 《Journal of the European Economic Association》2014,12(4):835-876
Over the last decade the World Management Survey (WMS) has collected firm‐level management practices data across multiple sectors and countries. We developed the survey to try to explain the large and persistent total factor productivity (TFP) differences across firms and countries. This review paper discusses what has been learned empirically and theoretically from the WMS and other recent work on management practices. Our preliminary results suggest that about a quarter of cross‐country and within‐country TFP gaps can be accounted for by management practices. Management seems to matter both qualitatively and quantitatively for performance at the level of the firm and the nation. Competition, governance, human capital, and informational frictions help account for the variation in management. We make some suggestions for both policy and future research. 相似文献
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This study investigates the differences in select organizational characteristics, managerial practices and work attitudes among 670 public and private sector workers in Brazil. The results indicate that in some aspects there is a moderation effect by type of organization. For example,when public employees score high on autonomy and task significance, perceive organizational practices as favourable, and keep membership in the same organization, they tend to be more satisfied than private sector workers. Overall, the findings highlight the need for more international comparisons to gain a better understanding of the public-private distinction. 相似文献
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The quadratic shortest path problem (QSPP) is the problem of finding a path with prespecified start vertex s and end vertex t in a digraph such that the sum of weights of arcs and the sum of interaction costs over all pairs of arcs on the path is minimized. We first consider a variant of the QSPP known as the adjacent QSPP. It was recently proven that the adjacent QSPP on cyclic digraphs cannot be approximated unless \(\hbox {P}=\hbox {NP}\). Here, we give a simple proof for the same result. We also show that if the quadratic cost matrix is a symmetric weak sum matrix and all s–t paths have the same length, then an optimal solution for the QSPP can be obtained by solving the corresponding instance of the shortest path problem. Similarly, it is shown that the QSPP with a symmetric product cost matrix is solvable in polynomial time. Further, we provide sufficient and necessary conditions for a QSPP instance on a complete symmetric digraph with four vertices to be linearizable. We also characterize linearizable QSPP instances on complete symmetric digraphs with more than four vertices. Finally, we derive an algorithm that examines whether a QSPP instance on the directed grid graph \(G_{pq}\) (\(p,q\ge 2\)) is linearizable. The complexity of this algorithm is \({\mathcal {O}(p^{3}q^{2}+p^{2}q^{3})}\). 相似文献
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Sara Molgora Valentina Fenaroli Laura Elvira Prino Luca Rollè Cristina Sechi Annamaria Trovato Laura Vismara Barbara Volpi Piera Brustia Loredana Lucarelli Renata Tambelli Emanuela Saita 《Women and birth : journal of the Australian College of Midwives》2018,31(2):117-123
Background
The prevalence of fear of childbirth in pregnant women is described to be about 20–25%, while 6–10% of expectant mothers report a severe fear that impairs their daily activities as well as their ability to cope with labour and childbirth. Research on fear of childbirth risk factors has produced heterogeneous results while being mostly done with expectant mothers from northern Europe, northern America, and Australia.Aims
The present research investigates whether fear of childbirth can be predicted by socio-demographic variables, distressing experiences before pregnancy, medical-obstetric factors and psychological variables with a sample of 426 Italian primiparous pregnant women.Methods
Subjects, recruited between the 34th and 36th week of pregnancy, completed a questionnaire packet that included the Wijma Delivery Expectancy Questionnaire, the Edinburgh Postnatal Depression Scale, the State-Trait Anxiety Inventory, the Dyadic Adjustment Scale, the Multidimensional Scale of Perceived Social Support, as well as demographic and anamnestic information. Fear of childbirth was treated as both a continuous and a dichotomous variable, in order to differentiate expectant mothers as with a severe fear of childbirth.Findings
Results demonstrate that anxiety as well as couple adjustment predicted fear of childbirth when treated as a continuous variable, while clinical depression predicted severe fear of childbirth.Conclusions
Findings support the key role of psychological variables in predicting fear of childbirth. Results suggest the importance of differentiating low levels of fear from intense levels of fear in order to promote adequate support interventions. 相似文献30.