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21.
The configuration of the novel three-stage L-band erbium-doped fiber amplifier with very large and flat gain and very low noise figure presented in this paper uses the forward ASE (amplified spontaneous emission) from the first section of the EDF (erbium-doped fiber) and the backward AS E from the third section of the EDF (both serve as the secondary pump sources of energy) to pump the second EDF. To improve the pump efficiency, the power of the pump is split into two parts(with a ratio of e.g. 2:7). The characteristics of this L-band EDFA are studied on the basis of the Giles Model with ASE.  相似文献   
22.
This mixed-methods research compared job satisfaction among counselors working in pre-schools and primary-schools. Its quantitative phase included 223 counselors, 70 of whom also participated in the qualitative phase. A demographic information form, job-satisfaction scale and a semi-structured interview protocol were used to collect data. Quantitative analysis indicated that the primary-school counselors’ job satisfaction was higher than that of the pre-school counselors. There were no statistically significant differences in satisfaction between the two groups based on gender, age, or marital status, or the interaction of any of those three demographic factors with the type of school where they worked. In the qualitative phase, approximately half of the primary-school counselors but just one-third of the pre-school counselors reported their job satisfaction as being high; and around half of the pre-school group and one-third of the primary-school group reported that school type where they worked had a negative impact on their job satisfaction.  相似文献   
23.
This paper addresses a neglected topic in the knowledge management literature: how the size of a network of actors affects the nature of intra-network social relations and knowledge processes. It makes a theoretical contribution to developing understanding in this area drawing on a range of literatures including practice-based perspectives on knowledge, the literature on the embeddedness of social relations, and relevant knowledge management literature. The central focus of this paper is on the relationship between network size, network density, and how these variables affect intra-network knowledge processes. It suggests that as network size increases network density is likely to decrease (as it becomes problematic for the actors in such networks to retain strong ties with a significant proportion of the network's members), which it will be suggested has significant ramifications for intra-network knowledge processes. This paper concludes by reflecting on the implications of the ideas developed for network-based forms of organizing, and innovation processes.  相似文献   
24.
OBJECTIVE: While research has supported associations between experiencing abuse and engaging in risky sexual behaviors during adolescence, research regarding these associations among adult women is much more equivocal. In addition, few studies have attempted to identify potential pathways from abuse experiences to sexual risk behaviors. The current study examined the associations between a history of physical or sexual abuse and recent sexual risk behaviors among adult women. Additionally, this study evaluated binge drinking and depressive symptomatology as potential mediators of any relationships between abuse history and sexual risk behaviors. METHODS: A total of 1,428 women between 18 and 40 years of age attending family planning clinic appointments completed a self-report survey regarding their recent sexual behaviors and sexual and physical abuse history. Logistic regressions using backward elimination were conducted to identify factors associated with sexual risk behavior. RESULTS: A history of physical abuse by a romantic partner was associated with several sexual risk behaviors. Few significant associations between intrafamilial physical or sexual abuse and recent sexual risk behaviors were found. Additionally, there was no evidence that these relationships were mediated by binge drinking or depressive symptomatology. CONCLUSIONS: Familial abuse experiences are not necessarily associated with recent sexual risk behaviors among adults. In contrast, physical abuse experiences, particularly those perpetrated by a romantic partner, are associated with engaging in adult sexual risk behaviors among women. However, these associations are not mediated by alcohol use or depressive symptomatology.  相似文献   
25.
导师如何通过“因材施教”的指导提升博士生的创新能力,是博士生培养的关注热点。基于481份“双一流”建设高校理工科博士生的调查数据,从导生双主体角度,以控制和支持两个维度的导生组合类型为自变量、博士生年级为调节变量,探索二者对理工科博士生创新能力的影响机制。研究发现,相较于导师低控制和学生低投入、导师低支持和学生低投入,其他导生组合类型均对理工科博士生的创新能力具有显著正向影响。年级在控制维度的导生组合类型对理工科博士生创新能力的影响中起调节作用。研究结果验证了导师阶段式培养的重要性,同时强调了博士生作为学习主体的关键性。  相似文献   
26.
Pigeons' keypecking was reinforced by food on baseline schedules of multiple variable interval (VI) x VI x and on contrast schedules of multiple VI x VI y. Deprivation of food was varied by maintaining subjects at 75%, 85%, and 95% (+/- 2%) of their free-feeding weights. Positive and negative behavioral contrast were observed. The size of the contrast was not systematically altered by changes in deprivation. Positive and negative contrast were both larger later in the session than they were earlier. Within-session decreases in responding were steeper for the baseline than for the contrast schedules for positive contrast. Within-session decreases were steeper for the contrast than for the baseline schedules for negative contrast. These results were predicted by the idea that different amounts of habituation to the reinforcer during the baseline and contrast schedules contribute to behavioral contrast. The results show that contrast occurs under conditions that reduce the effect of the following component. The results support the assumption that positive and negative contrast are produced by symmetrical theoretical variables.  相似文献   
27.
Today all parties within the health-care system demand more information and evidence to take more efficient and pinpointed management decisions. Their goal is a better patient and patient-care management. This paper presents an information visualisation approach to discover knowledge for the management of tele-home care for the elderly using the video-telephone: what type of elderly need what type of video-telephone interventions? This document focuses on the synthesis aspects of data mining with a view to knowledge discovery: the global, holistic, synthesis approach. More specifically, it summarises visually the relationships among the types of video-telephony care, among the segments of elderly, and between the types of interventions and the segments of elderly simultaneously. The graphical display allows delineating areas that group elderly with a similar/dissimilar video-telephony care profile. Information visualisation is a promising approach to provide insight into large multidimensional data sets. It fosters knowledge discovery.  相似文献   
28.
In this paper, social network analysis techniques and regression models are used to explain the impact of the level of knowledge development on ego-network redundancy in a community of hospital physicians. Our findings document that the level of knowledge development and the extent to which knowledge is homogeneously distributed amongst collaborating physicians are related to the redundancy of their advice networks, albeit with opposite effects. Our results highlight also that the impact of these relationships on network redundancy is moderated based on whether partnering individuals belong to different professional groups. Our results provide valuable input for the management of knowledge networks within professional organizations.  相似文献   
29.
Despite the large volume of research and managerial literature on knowledge management, many practitioners seem to find it difficult to appreciate its added value for their managerial work. This paper aims to understand and elaborate the added value that knowledge management as a managerial approach can bring to the management of knowledge-intensive organizations. This study explores empirically the actual management practices of a knowledge-intensive organization and examines how knowledge-related phenomena are managed as embedded aspects of management. This paper makes a contribution to prior discussions concerning the relevance of knowledge management and the role of knowledge management as an embedded management practice. The findings of this study should be useful in explaining practitioners the nature, relevance and value of knowledge management.  相似文献   
30.
This paper provides an overview of the knowledge management systems (KMSs) adopted by small and medium enterprises (SMEs). KMSs are divided into two categories: knowledge management tools (KM-Tools) and knowledge management practices (KM-Practices). On the basis of the analysis of the literature, two research questions (RQs) were identified and addressed through semi-structured interviews carried out in a sample of 35 SMEs operating in high-tech industries. The first RQ concerns the degree of adoption of KMSs by SMEs. The second RQ regards the relationship between KM-Tools and KM-Practices. As far as the degree of adoption of KMSs, the paper highlights that SMEs are not a homogeneous world but there are a variety of approaches and behaviours. As far as the relationship between the degree of adoption of KM-Tools and KM-Practices, the paper identifies three groups of SMEs that seem to point out the stages of the process of adoption of KMSs: Introduction, SMEs that deal with the process of knowledge management exploiting practices and tools that are already known; Growth, SMEs that adopt specialist practices of knowledge management acquiring new organisational and managerial competence in the field of knowledge management; Maturity, SMEs that invest in new technology and that acquire new technological competence in the field of knowledge management. This categorisation paves the way for further theoretical and practical implications for both managers and policy makers.  相似文献   
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