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991.
In this study, we examined optimal pricing strategies for “pay‐per‐time,” “pay‐per‐volume,” and “pay‐per‐both‐time‐and‐volume” based leasing of data networks in a monopoly environment. Conventionally, network capacity distribution includes short‐/long‐term bandwidth and/or usage time leasing. When customers choose connection‐time–based pricing, their rational behavior is to fully utilize the bandwidth capacity within a fixed time period, which may cause the network to burst (or overload). Conversely, when customers choose volume‐based strategies their rational behavior is to send only the minimum bytes necessary (even for time‐fixed tasks for real time applications), causing the quality of the task to decrease, which in turn creates an opportunity cost for the provider. Choosing a pay‐per time and volume hybridized pricing scheme allows customers to take advantage of both pricing strategies while lessening the disadvantages of each, because consumers generally have both time‐ and size‐fixed tasks such as batch data transactions. One of the key contributions of this study is to show that pay‐per both time and volume pricing is a viable and often preferable alternative to the offerings based on only time or volume, and that judicious use of such a pricing policy is profitable to the network provider. 相似文献
992.
Barbara Trotta Andrea Mosconi 《Australian and New Zealand Journal of Family Therapy》2021,42(1):21-29
The COVID‐19 pandemic has impacted the personal and professional lives of all of us and has laid the bases for a social and cultural change. This article is written as a reflection on the paradoxical effects of the ‘viral phenomenon.’ We wish to highlight the opportunities and changes that have arisen from the emergency situation, especially through the use of the online setting, both in the clinical work and training activities of systemic therapists. This article is not intended to be a panegyric on the merits of digital sessions, but an appraisal, also through clinical examples, of the contributions that technology may give to our practices. We do not consider technology as a substitute, but as an integration and enrichment of the therapist's and trainer's tools. This tough experience may be transformed into an opportunity for learning new techniques and practices in which the screen becomes a useful support. 相似文献
993.
The COVID‐19 pandemic has taken a toll on all individuals and their families around the world. Some suffer more adversely than others depending on their unique developmental needs, resources, and resilience. However, instead of breaking down, many families and therapists have hunkered down to cope with this ‘wicked’ situation as it continues to evolve. This article examines the unique challenges and opportunities of COVID‐19 for families at different life developmental stages, as well as the challenges and opportunities for systemic therapists as they venture into unfamiliar territory. Through a case example and by integrating recent literature related to this pandemic, we apply three key and interconnected systemic themes (unsafe uncertainty, family life cycle, and social diversity) to discuss the challenges and opportunities for families and therapists, respectively. We are optimistic that there are many possibilities as families and therapists draw on, and often reinvent, currently available resources to navigate their course in this pandemic. We also find that while the pandemic continues to present unsafe and uncertain situations, there are new ways of being and behaving, especially when families and professionals work together collaboratively. Despite formidable challenges, there are many opportunities, both within families and communities that cut through different social contexts related to family, culture, economics, and even politics. Families and therapists could endure better when they are more cognisant of how and what these contexts may impact and offer them. 相似文献
994.
Myrtle P. Bell Daphne Berry Joy Leopold Stella Nkomo 《Gender, Work and Organization》2021,28(Z1):39-57
In this article, as have many Black women scholars in the past, we again call for collective action against anti‐blackness and White supremacy in the academy. Drawing from black feminist theory, we discuss the long history of Black women academics' activism against anti‐black racism and introduce the current movement: Black Lives Matter (BLM). Although BLM is often construed as resisting anti‐black violence outside the academy, it is also relevant for within the academy wherein anti‐blackness is likely to be manifested as disdain, disregard, and disgust for Black faculty and students. We discuss some of the ways in which anti‐blackness and liberal White supremacy are manifested in the lives of Black faculty and students, and propose that non‐Black allies have key roles to play in resisting them. Like second‐hand cigarette smoke that harms everyone in proximity, anti‐blackness and White supremacy harm us all, and a shared movement is needed to dismantle them. 相似文献
995.
Karyn E. Miller 《Gender, Work and Organization》2021,28(Z1):260-265
The COVID‐19 pandemic has upended the lives of working parents as they strive to meet the conflicting demands of childcare and professional obligations. While growing evidence suggests the extraordinary challenges to time and work brought by the pandemic, this article explores the pandemic as an opportunity for stillness and reflection, a personal and professional recalibration. Through a personal narrative describing my experiences as an academic and mother before and during the pandemic, framed within the ethics of care, this article brings light to the untenable reality of working mothers pre‐pandemic, explores the ways in which the pandemic has positively facilitated caring relationships at home as well as the reallocation of time and household responsibilities, and argues for policy and legislative action at the institutional and societal levels that support and value the care work of women and men alike. 相似文献
996.
Chiara Giordano 《Gender, Work and Organization》2021,28(Z1):137-150
As a consequence of the lockdown measures imposed by the Belgian government to fight against COVID‐19, migrant live‐in elderly carers had to choose between safeguarding their job — at the detriment of their personal freedom, their health and their working conditions — and safeguarding their freedom but losing their job — at the detriment of their economic survival and that of their families. This article explores this dilemma from an intersectionality perspective. In order to understand their experience in times of COVID‐19 and their response to this dilemma, I analyse their position as women, as migrants, as elderly care workers, as family breadwinners and as ‘quasi‐family members’ in the families of their employer — which correspond to five interlocking systems of oppression. 相似文献
997.
基于射频技术的无线识别系统设计 总被引:1,自引:0,他引:1
本无线识别系统的设计利用射频技术,阅读器将呼叫信号加载到频率为70MHZ的射频上,以无线方式发给应答器。呼叫信号经过线圈耦合、解调、电压比较器等电路传送到应答器的控制器。控制器对呼叫信号进行分析、确认后,将存储的四位二进制编码通过发送端的调制电路馈送到阅读器,并显示应答器的具体信息。 相似文献
998.
This paper describes an approach for calculating sample size for population pharmacokinetic experiments that involve hypothesis testing based on multi‐group comparison detecting the difference in parameters between groups under mixed‐effects modelling. This approach extends what has been described for generalized linear models and nonlinear population pharmacokinetic models that involve only binary covariates to more complex nonlinear population pharmacokinetic models. The structural nonlinear model is linearized around the random effects to obtain the marginal model and the hypothesis testing involving model parameters is based on Wald's test. This approach provides an efficient and fast method for calculating sample size for hypothesis testing in population pharmacokinetic models. The approach can also handle different design problems such as unequal allocation of subjects to groups and unbalanced sampling times between and within groups. The results obtained following application to a one compartment intravenous bolus dose model that involved three different hypotheses under different scenarios showed good agreement between the power obtained from NONMEM simulations and nominal power. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
999.
In longitudinal clinical trials, a common objective is to compare the rates of changes in an outcome variable between two treatment groups. Generalized estimating equation (GEE) has been widely used to examine if the rates of changes are significantly different between treatment groups due to its robustness to misspecification of the true correlation structure and randomly missing data. The sample size formula for repeated outcomes is based on the assumption of missing completely at random and a large sample approximation. A simulation study is conducted to investigate the performance of GEE sample size formula with small sample sizes, damped exponential family of correlation structure and non‐ignorable missing data. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
1000.
In order to investigate the influence of maternal mental illness postpartum on mother‐infant and father‐infant interaction, infants of 14 mentally ill women admitted to hospital within 6 months after delivery were compared to infants of 22 women who had been somatically ill. Videotaped sessions when the infant was 10 months old revealed that mothers in the psychiatric sample showed less sensitivity in comparison to mothers in the somatic sample. When the infant was 2 years old, mothers in the psychiatric sample showed less positive affect and less link‐infant follow (stimulation dimension) as compared to the somatic mothers. However, there were no differences between fathers in the psychiatric sample and fathers in the somatic sample in any of the interaction variables. In the psychiatric sample, fathers showed more warmth as compared to mothers. In the somatic sample, fathers scored higher than mothers on autonomy but lower than mothers on link‐infant follow (stimulation dimension). A possible interpretation of our data was that the mental illness of the mothers may lead to a more active parenting role of the father in order to buffer the deficit in the mother‐infant relation. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献