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91.
In this paper,we propose a random-access model for describing several wireless communication technologies. These networks have found application in the construction of wireless sensor networks, and the proposed model can be used for flows with different properties, considering the corresponding distribution functions. The model considers the technical features of the LoRa technology and subscriber traffic. We also address the management of random multiple wireless access in a Software-Defined Networking (SDN) like control architectures, and proposing a model for flows with different properties, considering the corresponding distribution functions. We develop a method for optimizing the parameters of an access network by the probability of data delivery. Then we describe the probability of bit error, frame loss, collision, and the choice of network parameters considering the heterogeneity of conditions for different users. Numerical results show the efficiency of our proposed scheme by maintaining the required network parameters in case of its function conditions changing.  相似文献   
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93.
如何揭示群体规范和公平价值在个体心理发展中的作用机理, 提升儿童-青少年在群际互动当中的公平感知与规范执行, 是教育心理领域的关键问题。公平规范执行中内群体偏爱现象是近年来的研究热点之一, 然而先前研究存在以下不足:1)大多采用问卷法, 易受社会赞许性的影响, 存在言行不一致的情况; 2)大多采用情景实验, 聚焦社会互动的最终行为输出端, 无法实时有效地把握社会决策的动态进程; 3)脑成像研究仍以fMRI技术为主, 侧重于评估认知加工潜在的脑区激活模式及各脑区间的功能连接, 缺乏对群际公平规范执行中大脑激活动态模式的精确把握。针对这些不足, 本项目从资产分配情景出发, 以儿童和青少年为研究对象, 联合运用认知、行为、眼动和电生理等多层次测评手段, 对公平规范执行中内群体偏爱的发生过程进行认知解析, 探讨认知控制和心智化在其间的关键作用机制及其心理发展轨迹。研究结果将服务于中小学管理中的德育教育, 引导与培养学生的公正感与行为。  相似文献   
94.
Within the framework of modern evolutionary theory, arguments are reviewed that the nonlegal equivalent of aggressive criminal behavior may have evolved by natural selection among mammals, particularly primates, as part of their overall approach to reproduction. If so, the commission of aggressive crimes (or their nonlegal equivalent) by humans, and even efforts to prevent fellow social group members from being victimized by aggressive crimes, may also be partially explainable in natural selection terms. The plausibility of this deduction was explored, first, by specifying the three elements that a human act must have to be regarded as an aggressive crime. Summarily, these were that (1) injury to a victim must be a likely result of the act, (2) the act must be intended, and (3) the act must elicit negative responses from those witnessing it. The primate behavior literature was examined for evidence that some behavior of nonhumans met all three conditions. Affirmative results were obtained. Therefore, while further research is in order, human aggressive criminal behavior, as well as human efforts to control it, seem to have close parallels in other primates. This would be consistent with the notion that aggressive criminal behavior (along with its condemnation by fellow group members) is part of a social system produced and sustained by natural selection.  相似文献   
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96.
The association between the life orientation and attributional styles of a mother and the aggressiveness of her child were studied in 61 mothers and their children, 23 boys and 38 girls, mean age 6.6 years (range 4–13 years). The mother's life orientation and attributional styles were established during interviews using the life-style questionnaire, and a child's aggressiveness was evaluated by the mother using the Health Examination Survey. The factors assessing life orientation were lack of personal control, causal unstability, internal locus of causality, personal responsibility, and democratic educational attitudes. The mother's personal responsibility and internal causal attributions were related to nonaggressiveness in the child, whereas mothers with a lack of personal control were likely to have aggressive children. Educational attitudes were of no importance. The results showed no sex- or age-related variance.  相似文献   
97.
In Uganda, one in five children presents mental health challenges, including disruptive behavior disorders (DBDs). DBDs can persist through adulthood and result in negative outcomes. Effective interventions for DBDs have been developed and tested in high-poverty communities in developed countries. Yet, most African countries, such as Uganda, lack such interventions. This paper describes the adaptation process of an evidence-based intervention of U.S. origin to optimize fit to context with intervention fidelity, as part of a randomized trial conducted with youth that exhibit behavioral challenges and their caregivers in 30 schools in Uganda. The process involved: initial meetings with headteachers and teachers to introduce the study and the main concepts of the intervention; initial manual review focusing on 4Rs and 2Ss content by the Uganda team; engagement of community stakeholders for additional feedback on content and cultural relevance; final revision of the manual; and collection of children’s drawings for the illustration of the manual. This paper describes both similarities and differences between the original and adapted intervention content and methods of delivery. The findings also highlight the importance of involving community stakeholders in the adaptation process.  相似文献   
98.
This study examined the association between grandparental co-residence and child academic and behavioral outcomes using a sample from Shanghai, China (n = 1,763), and was built on two theoretical perspectives: intergenerational solidarity theory and the contextual model of family stress. These models integrate the impact of residential and relational proximity to grandparents on child well-being and underscore the importance of family context. This study also explored the moderating effects of family resources using proxies that prior theoretical and empirical studies have found to be important to such associations: family income, parental education, hukou status, and subjective social status. Results indicated that among families without co-residing grandparents, rural and low-income parents reported their children to have more externalizing behavioral issues than their respective urban and non-low-income counterparts. In addition, children who resided in poorly resourced families (i.e., low family income, low parental education, low subjective social status, or rural hukou status) tended to benefit from living with grandparents compared to their well-resourced counterparts in terms of lower externalizing and internalizing behaviors reported by teachers. These results do not negate the potential beneficial effects of living with grandparents for children in well-resourced environments. Implications for practice and policy, as well as future research directions, are discussed.  相似文献   
99.
High levels of risk perception of terrorism (RPT) may impair an individual's quality of life and welfare. To understand the mechanisms responsible for RPT, this study investigated the association of gender and coping styles with individual differences in two key elements of RPT: perceived control and perceived vulnerability. A convenience sample of 400 Israelis (181 men and 219 women) filled out questionnaires on sociodemographic background, RPT and coping. Employing a multidimensional approach for coping, we divided participants into four coping types: problem-focused (n = 65), emotion-focused (n = 70), mixed (n = 122) and minimal (n = 142). The results indicate that problem-focused coping is associated with higher levels of perceived control than other types of coping and mixed coping is associated with higher levels of perceived vulnerability than other coping strategies. Also, interactions between gender and exposure to terrorism contributed to understanding the differences in perceived control. The discussion addresses gender differences in RPT and coping in the context of traditional gender roles. The study concludes with implications for risk management and therapeutic interventions regarding high levels of fear of terrorism.  相似文献   
100.
Perfectionism and impulsivity are multidimensional constructs. While different perfectionism dimensions are exclusively measured through self-reports, different impulsivity dimensions can be measured through self-report or behaviour via preferences for different rewards. This study explored differential associations between perfectionism and impulsivity based on both dimension and measurement modality (self-report/behavioural). We then examined whether adaptive or maladaptive perfectionism would be differentially associated with impulsivity. Two-hundred and six students completed two perfectionism and three impulsivity measures (two self-report; one behavioural). Two self-report impulsivity measures were associated with specific perfectionism dimensions, whereas the behavioural measure was not associated with perfectionism. Maladaptive perfectionism was associated with decreasing impulsivity, whereas adaptive perfectionism was associated with increasing impulsivity. Perfectionism related to impulsivity differently depending on how each construct was measured.  相似文献   
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