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71.
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   
72.
73.
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   
74.
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   
75.
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   
76.
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   
77.
Murray Sidman's contributions to the science of behavior span many areas including avoidance behavior, coercion and its effects, stimulus control, errorless learning, programmed learning, stimulus equivalence, and single-subject methodology. He was also a great mentor to many and helped shape the discipline we now call behavior analysis. In this memoriam, we briefly highlight his scholarly legacy and share some personal anecdotes.  相似文献   
78.
Abstract

Optic flow (OF) has been utilized to investigate the sensory integration of visual stimuli during postural control. It is little known how the OF speed affects the aging brain during the sensory integration process of postural control. This study was to examine the effect of OF speeds on the brain activation using functional near-infrared spectroscopy (fNIRS) and postural sway between younger and older adults. Eleven healthy younger adults (5M/6F, age 22?±?1-year-old) and ten healthy older adults (4M/6F, age 71?±?5-year-old) participated in this study. A virtual reality headset was used to provide the OF stimulus at different speeds. A forceplate was used to record the center-of-pressure to compute the amplitude of postural sway (peak-to-peak). Compared with younger adults, older adults showed significantly increased activation in the OF speed of 10?m/s and decreased activation in the OF speed of 20?m/s in the left dorsolateral prefrontal cortex. Older adults also showed decreased activation in the left temporoparietal region (VEST) in the OF speed of 20?m/s. A significant difference in peak-to-peak was found between groups. Our results indicated that age might be associated with the ability to process fast OF stimulation.  相似文献   
79.
80.
In June 2016, the United Kingdom voted to leave the European Union. Voting followed a general trend: disadvantaged areas of the United Kingdom tended to vote “leave,” and more affluent areas tended to vote “remain.” This project investigates the psychological variables underlying this overall trend by distinguishing four psychological motivations: the need for justice, threat reduction needs, need to belong, and the need for control. Participants were recruited from different areas across Greater Manchester (N = 158). A survey assessed voting preference, socioeconomic status, collective relative deprivation (CRD), perceptions of threat from immigration, European and British identification, sense of control in life, and relative gratification. Discriminant function analysis showed that leave voting was characterized by greater realistic threat, symbolic threat, CRD, and British identification. Remain voting was characterized by strong European identification. Findings highlight that a need for justice, threat-reduction needs, and identity needs were key predictors of voting behavior.  相似文献   
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