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331.
In this article, we provide a wide-ranging review of recent research on leader individual differences. The review focuses specifically on the explosion of such research in the last decade. The first purpose of this review is to summarize and integrate various conceptual frameworks describing how leader attributes influence leader emergence and leader effectiveness. The second purpose is to provide a comprehensive review of empirical research on this relationship. Also, most prior reviews primarily examined leader personality traits; this review includes a broader array of leader attributes, including cognitive capacities, personality, motives and values, social skills, and knowledge and expertise. The final broad purpose of this paper is to review and integrate situational and contextual parameters into our conceptual framing of leader individual differences. Few, if any, prior reviews have systematically accounted for the critical role of such parameters in cuing, activating, or delimiting the effects of particular leader attributes. We do so in this article.  相似文献   
332.
Network coding is a generalization of conventional routing methods that allows a network node to code information flows before forwarding them. While it has been theoretically proved that network coding can achieve maximum network throughput, theoretical results usually do not consider the stochastic nature in information processing and transmission, especially when the capacity of each arc becomes stochastic due to failure, attacks, or maintenance. Hence, the reliability measurement of network coding becomes an important issue to evaluate the performance of the network under various system settings. In this paper, we present analytical expressions to measure the reliability of multicast communications in coded networks, where network coding is most promising. We define the probability that a multicast rate can be transmitted through a coded packet network under a total transmission cost constraint as the reliability metric. To do this, we first introduce an exact mathematical formulation to construct multicast connections over coded packet networks under a limited transmission cost. We then propose an algorithm based on minimal paths to calculate the reliability measurement of multicast connections and analyze the complexity of the algorithm. Our results show that the reliability of multicast routing with network coding improved significantly compared to the case of multicast routing without network coding.  相似文献   
333.
This paper studies a new version of the location problem called the mixed center location problem. Let P be a set of n points in the plane. We first consider the mixed 2-center problem, where one of the centers must be in P, and we solve it in \(O(n^2\log n)\) time. Second, we consider the mixed k-center problem, where m of the centers are in P, and we solve it in \(O(n^{m+O(\sqrt{k-m})})\) time. Motivated by two practical constraints, we propose two variations of the problem. Third, we present a 2-approximation algorithm and three heuristics solving the mixed k-center problem (\(k>2\)).  相似文献   
334.
We investigate special cases of the quadratic minimum spanning tree problem (QMSTP) on a graph \(G=(V,E)\) that can be solved as a linear minimum spanning tree problem. We give a characterization of such problems when G is a complete graph, which is the standard case in the QMSTP literature. We extend our characterization to a larger class of graphs that include complete bipartite graphs and cactuses, among others. Our characterization can be verified in \(O(|E|^2)\) time. In the case of complete graphs and when the cost matrix is given in factored form, we show that our characterization can be verified in O(|E|) time. Related open problems are also indicated.  相似文献   
335.
Studies show that fathers report work–family conflict levels comparable to mothers. The authors examine gender differences in work‐related strategies used to ease such conflicts. The authors also test whether the presence of young children at home shapes parents' use of different strategies. They address these focal questions using panel data from the Canadian Work, Stress, and Health study (N = 306 fathers, 474 mothers). The authors find that mothers with young children are more likely to scale back on work demands when compared with fathers with young children, but mothers and fathers with older children are equally likely to pursue these strategies. Furthermore, women with young children and men with older children are more likely to seek increased schedule control as a result of work–family conflict when compared with their parent counterparts. The authors situate these findings in the vast literature on the consequences of work–family conflict.  相似文献   
336.
The most universally experienced sexual response is sexual desire. Though research on this topic has increased in recent years, low and high desire are still problematized in clinical settings and the broader culture. However, despite knowledge that sexual desire ebbs and flows both within and between individuals, and that problems with sexual desire are strongly linked to problems with relationships, there is a critical gap in understanding the factors that contribute to maintaining sexual desire in the context of relationships. This article offers a systematic review of the literature to provide researchers, educators, clinicians, and the broader public with an overview and a conceptual model of nonclinical sexual desire in long-term relationships. First, we systematically identified peer-reviewed, English-language articles that focused on the maintenance of sexual desire in the context of nonclinical romantic relationships. Second, we reviewed a total of 64 articles that met inclusion criteria and synthesized them into factors using a socioecological framework categorized as individual, interpersonal, and societal in nature. These findings are used to build a conceptual model of maintaining sexual desire in long-term relationships. Finally, we discuss the limitations of the existing research and suggest clear directions for future research.  相似文献   
337.
Schools at the P-12 level increasingly face crises related to school shootings, violence, and other tragedies. Understanding the communication challenges schools face is paramount to assisting schools with communication before, during, and after crisis events. The current study focuses on the challenges created by media interest in such crises and the strategies implemented to overcome these challenges and provide responsible information to stakeholders. Interviews conducted with 21 school crisis teams at the P-12 level revealed that sensationalism, seeking alternative routes to information, and framing were key challenges in working with the media. In light of these challenges, administrators focused on creating media plans, building relationships with the media, being accurate but guarded, and communicating reassurance and reunification. Implications are discussed for school districts nationally.  相似文献   
338.
For nearly four decades, child welfare policy and practice have focused on the achievement of legal permanence for children in foster care. Although federal child welfare policy has resulted in the movement of children from state custody to legally permanent adoptive or guardianship families, little is known about the quality and enduring nature of these placements. A significant challenge of the twenty-first century child welfare system is how to ensure the well-being of children currently living with adoptive parents or guardians. This paper discusses child welfare policy and trends related to post-permanency well-being, including the decrease in Title IV-E foster care caseloads nationwide and the simultaneous increase in Title IV-E adoptive and guardianship caseloads. We highlight the needs of a twenty-first century child welfare system, including increased federal efforts to ensure child permanence and well-being after legal adoption or guardianship has been achieved, as well as more rigorous longitudinal and interdisciplinary research focused on the post-permanency adjustment of children and their families.  相似文献   
339.
Rhetorical questions emerging spontaneously in consultations can be used as a tool for developing self‐reflexivity and exploring the therapeutic alliance in the process of therapy with couples and families. This paper presents a technique based on the enunciation of rhetorical questions, which can point to an impasse in the process of therapy and contain a key to its resolution. The technique focuses on the distinctive feature of rhetorical questions as convening a paradoxical injunction: a question not intended as a question, while uttered as such. The technique in four steps is illustrated by examples from therapy, supervision, consultation, and self‐supervision. Its focus is the interlink between the therapeutic relationship and the process of therapy and it is informed by a second‐order cybernetics approach, dialogical practice, and the systemic literature on emotion. The technique can help develop curiosity in working with families, lead to unforeseen developments, and touch on prejudices not made explicit in previous therapeutic encounters. Whether we are acting as supervisors, therapists, or clients, the creation of a ‘secure enough’ context for rhetorical questions becomes critical to allow freeform exploration.  相似文献   
340.
Undergraduate career planning courses have shown efficacy in decreasing students’ negative career thoughts; however, universities have minimally applied these courses to science, technology, engineering, and math (STEM) populations. This study compared the influence of a STEM‐focused career planning course for undecided STEM students with a seminar course for decided STEM majors. An analysis of covariance with covariate adjustment revealed that undecided career planning students had lower adjusted mean scores on a measure of negative career thinking than the decided STEM majors after the first semester of college. The results provide support for the efficacy of STEM‐focused career planning courses and measuring negative career thoughts with STEM undergraduates.  相似文献   
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