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11.

The capacity of cyberspace to bypass some of the spatial divisions that underpin social inequality endows it with political significance. This article examines some of the ways in which cyberspace has contributed to redrawing the boundaries between public and private and some of the consequences of this for people, things, and ideas in Iran and the Iranian diaspora. It shows how cyberspace influences a wide range of political phenomena including political mobilization and censorship, intergenerational communication, identity formation, sexuality, sense of belonging, and forms and location of symbolic capital. The relationship between net users in the diaspora and cyberspace involves a circuit of reorderings of one's understanding of the diaspora, one's contact with it in cyberspace, of one's own ideas on the basis of what one finds there, and of social relationships established and maintained in cyberspace. Paradoxically, the very richness and diversity of the ideas and opinions found in Iranian cyberspace may undermine the idea of there actually being a single Iranian diaspora.  相似文献   
12.
In this paper, we consider a linear mixed model with measurement errors in fixed effects. We find the corrected score function estimators for the variance components. An iterative algorithm is proposed for estimating the parameters. The computations on each iteration of this algorithm are those associated with computing estimates of fixed and random effects for given values of the variance components. We also derive the consistency of the estimators under regularity conditions. The simulation study shows that for relatively small sample size the corrected estimators perform very well. Finally, an example of real data is given for illustration.  相似文献   
13.
Suicide is a leading cause of death among youth globally. In this critical interpretive synthesis, we examined literature on resiliency factors and suicidality. Systematic searches identified 474 articles, 37 of which were included. Results revealed internal (positive self‐appraisal, zest for life, personal traits, and coping skills) and external factors (social support system and inclusive environments) contribute to resilience among youth, with age, sex and gender, and Indigenous identity as important intersecting considerations. Findings validated fostering resilience as primary suicide prevention among youth, with little explanation for how these factors may work to protect youth from suicidality. Continued research in this area requires a focus on how to promote resilience at the community and systems levels.  相似文献   
14.
This article presents ongoing research that focuses on efficient allocation of defense resources to minimize the damage inflicted on a spatially distributed physical network such as a pipeline, water system, or power distribution system from an attack by an active adversary, recognizing the fundamental difference between preparing for natural disasters such as hurricanes, earthquakes, or even accidental systems failures and the problem of allocating resources to defend against an opponent who is aware of, and anticipating, the defender's efforts to mitigate the threat. Our approach is to utilize a combination of integer programming and agent‐based modeling to allocate the defensive resources. We conceptualize the problem as a Stackelberg “leader follower” game where the defender first places his assets to defend key areas of the network, and the attacker then seeks to inflict the maximum damage possible within the constraints of resources and network structure. The criticality of arcs in the network is estimated by a deterministic network interdiction formulation, which then informs an evolutionary agent‐based simulation. The evolutionary agent‐based simulation is used to determine the allocation of resources for attackers and defenders that results in evolutionary stable strategies, where actions by either side alone cannot increase its share of victories. We demonstrate these techniques on an example network, comparing the evolutionary agent‐based results to a more traditional, probabilistic risk analysis (PRA) approach. Our results show that the agent‐based approach results in a greater percentage of defender victories than does the PRA‐based approach.  相似文献   
15.
Considered process in this article is a two-stage dependent process. Each item in this process has two quality characteristics as x and y while x and y are related to the stage 1 and 2, respectively. Each stage has two operational states as the in-control state and out-of-control state and transition time from the in-control state to the out-of-control state follows a general continues distribution function. The process is monitored using a chi-square control chart. An integrated model that coordinates the decisions related to the economic design of the used control chart and maintenance planning is presented. For the evaluation of the integrated model performance, a stand-alone maintenance model is also presented, and the performance of these two models is compared with each other.  相似文献   
16.

Problem

The steep increase and inappropriateness of caesarean birth represent a healthcare problem in Iran.

Aim

The purpose of study was to evaluate the effect of a campaign based on social marketing to promote normal childbirth.

Method

The study was designed as a prospective case control study. The social marketing campaign was implemented from March 2016 to January 2017. A demographic data questionnaire, obstetrical history questionnaire, maternal knowledge assessment questionnaire, and maternal health belief questionnaire comprised the instruments for this study. Only women planning a caesarean birth without any medical indications for the caesarean were enrolled in the study as a case. Those who met the same inclusion criteria and did not want to participate in the campaign were assigned to the control group.

Findings

In total, 350 first-time pregnant women who composed the campaign group (n = 194) and control group (n = 156) completed the study. The mean baseline level of knowledge and Health Belief Model component score did not differ between the two groups at baseline. However, after the campaign, knowledge scores, perceived severity, perceived susceptibility, self-efficacy, and cues to action scores differed significantly between the campaign and control groups. The follow-up of all participants in both groups showed that 35.6% (n = 69) of participants in the campaign group chose natural birth as their birth method, whereas only 13.5% (n = 21) in the control group delivered their newborn vaginally.

Conclusion

The B Butterfly social marketing campaign successfully targeted first-time pregnant women who chose to have unnecessary elective cesarean births.  相似文献   
17.
Implementation of enterprise resource planning systems (ERPs) is a complex and costly task which usually results in serious failures. Numerous factors affect these projects implementation due to their size, complexity and high chance of failure. Therefore, identifying these factors in ERP projects is a critical issue. The majority of previous publications have been conducted in identifying ERP critical success factors (CSFs) rather than critical failure factors (CFFs). In order to help practitioners, this article studies the CFFs in ERP implementation projects. The implications of interdependency among failure factors are also usually overlooked by project managers due to perceived complexity in modelling and analysing influential factors. With this in mind, we have proposed a fuzzy cognitive map (FCM)-based dynamic model of ERP failure factors through project lifecycle phases. The main advantage of FCM lies in them being capable of modelling complex phenomena based on the experts’ perceptions. This tool models uncertainty and related events, imitating human reasoning. Moreover, FCMs enable the developing of forecasting exercises through simulations. Practitioners would thus assess the joint influence of ERP implementation failure factors on project outcomes. The results make known to practitioners which problems will arise if the failure factors are not treated, and how these will impact on the outcomes of projects. Therefore, the proposed approach would help them to manage ERP implementation projects in a more effective and proactive way.  相似文献   
18.
19.
Constrained utility maximization underlies much consumer behavior in economics. Opportunities for solving important problems are ever present. However, most potential applications remain potential because existing software packages are not able to estimate the systems of equations necessary to identify the utility function. At least three features often conspire to make these problems intractable: the size of the system of equations that must be estimated, the lack of any theory for imposing zero restrictions on many of the parameters of the nonadditive utility functions, and the necessity to insure negative definiteness consistent with the axioms of consumer behavior. This paper develops an approach and illustrates the stepwise least squares estimator of a group of equations by application to the demand for food items.  相似文献   
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