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221.
The contribution of individual characteristics to predicting individual, community and national resilience of Israeli Jews and Arabs was investigated. Psychological resilience refers to people's assessment of their ability to withstand negative psychological consequences of major afflictions, and to keep functioning despite these adversities. The following hypotheses were examined: 1. The Jewish sample would score higher than the Arab sample on indices of individual, community and national resilience. 2. Men of both groups would score higher compared with women on these resilience indices. 3. Exposure to terror and fear of upcoming war would negatively predict the resilience of both groups. 4. Higher level of religiosity, right wing political attitudes, higher income, higher education, older age and higher sense of coherence will positively predict the investigated resiliencies. The random sample included 1100 Jews and 350 Arabs who participated in an internet survey. Resilience was defined in this study as the balance of individual, community and national strength (protective factors) to vulnerability (risk factors). The results supported the first three hypotheses whereas the fourth hypothesis was supported only for the Jewish sample. The present study indicated that some predictors had universal effect on resilience, whereas others seemed to be culture specific predictors.  相似文献   
222.
This paper focuses on the computation issue of portfolio optimization with scenario-based Value-at-Risk. The main idea is to replace the portfolio selection models with linear programming problems. According to the convex optimization theory and some concepts of ordinary differential equations, a neural network model for solving linear programming problems is presented. The equilibrium point of the proposed model is proved to be equivalent to the optimal solution of the original problem. It is also shown that the proposed neural network model is stable in the sense of Lyapunov and it is globally convergent to an exact optimal solution of the portfolio selection problem with uncertain returns. Several illustrative examples are provided to show the feasibility and the efficiency of the proposed method in this paper.  相似文献   
223.
Wireless Sensor Networks is one of the most significant area of research where large number of sensor nodes that are distributed in a geographical area operate on limited battery power. As these networks, depending on the application, are sometimes deployed in in-hostile environment, which makes energy conservation one of the major challenge faced in WSN. To reduce energy consumption, clustering is considered to be the most efficient technique. This work proposes a new clustering approach that decreases energy consumption and results in prolonged network lifetime which is an important requirement for networks operating in inaccessible areas. In the proposed approach, heterogeneity is also implemented to increase the stability and energy efficiency of random networks. We have evaluated the efficiency of the proposed protocol through simulations and comparison is performed with well-known existing distributed protocols. Proposed approach shows efficient results in terms of the stability period for different network configurations and Base Station positions. Also, the results are found better in terms of number of alive nodes and network lifetime.  相似文献   
224.
The cognitive interview (CI) has been an effective method for interviewing eyewitnesses often leading to changes in legislation and practice in many countries. This study was the first to employ the CI in Iran and test whether category clustering recall (CCR) was superior to a free recall when incorporated within an investigative interview. A between‐subjects design assigned 66 participants to one of three interview conditions after they watched a mock robbery. The participants were interviewed 48 hr later using either a structured interview (SI), the CI, or a modified cognitive interview (MCI) that replaced free recall with CCR at the first retrieval attempt. Analysis of variance suggests CCR was more effective than free recall and the CI group recalled more information than the SI group, replicating the CI superiority effect. This has implications for law enforcement in Iran and worldwide by suggesting these techniques can be used to enhance recall.  相似文献   
225.
The present study concerns a Dutch computer-based assessment, which includes an assessment process about information literacy and a feedback process for students. The assessment is concerned with the measurement of skills in information literacy and the feedback process with item-based support to improve student learning. To analyze students’ feedback behavior (i.e. feedback use and attention time), test performance, and speed of working, a multivariate hierarchical latent variable model is proposed. The model can handle multivariate mixed responses from multiple sources related to different processes and comprehends multiple measurement components for responses and response times. A flexible within-subject latent variable structure is defined to explore multiple individual latent characteristics related to students’ test performance and feedback behavior. Main results of the computer-based assessment showed that feedback-information pages were less visited by well-performing students when they relate to easy items. Students’ attention paid to feedback was positively related to working speed but not to the propensity to use feedback.  相似文献   
226.
Research examined the effects of a supervised physical activity program on potential psychosocial mediators and determined whether changes in these psychosocial variables predicted changes in physical activity and fitness. Sedentary adolescent females were assigned to an intervention (n?=?79) or comparison (n?=?67) group. Cardiovascular fitness (cycle ergometer), physical activity (3-Day Physical Activity Recall), and psychosocial variables related to physical activity (i.e., self-efficacy, perceived barriers, social support, enjoyment) were assessed at three time points over the 9-month study. An intention-to-treat analysis showed that the intervention did not impact any of the psychosocial variables, with the exception of perceived barriers, which increased in the intervention group. Longitudinal analyses showed that improvements in fitness were associated with positive changes in global self-efficacy and exercise enjoyment. Psychosocial variables did not mediate the program's effects on fitness or activity. However, individual level changes in psychosocial variables were related to changes in cardiovascular fitness.  相似文献   
227.
This study examined how mindfulness and integrative self‐knowledge were related to health‐related issues. Men in general population (n = 103) and coronary heart disease samples (n = 101) completed the Mindful Attention Awareness Scale, the Integrative Self‐knowledge Scale, the Type 2 subscale of the Interpersonal Reactions Inventory, the Perceived Stress Scale, and the Anxiety and Depression Scales. In both samples, there was a moderate positive correlation between mindfulness and integrative self‐knowledge and they were negatively correlated with all health‐related variables. However, only integrative self‐knowledge explained independent variance in health‐related variables. Specifically, in both samples, the relationship between mindfulness and health‐related variables was mediated by integrative self‐knowledge. Mindfulness and integrative self‐knowledge are related domains of self‐awareness that are associated with a range of health‐related variables. These relationships are robust across samples drawn from general population and patients with coronary heart disease. The finding that integrative self‐knowledge explained additional variance in the health‐related variables after the contribution of mindfulness had been accounted for suggests that reflective self‐awareness in integrative self‐knowledge may make a unique contribution to the explanation of individual differences in health variables.  相似文献   
228.
While it is now widely recognized that a general factor (GFP) can be extracted from most personality data, this finding has been subject to numerous critiques: (1) that the GFP is an artefact due to socially desirable responding; (2) that it is factorially indeterminate; (3) that it can be more parsimoniously modelled using blended variables; (4) that it shows less genetic variance due to dominance than should be true of a fitness trait; (5) that it correlates more weakly with g than would be predicted from Life History theory; (6) that it cannot be recovered across personality inventories. We present new evidence and argument to show that each of these critiques is open to reasonable doubt.  相似文献   
229.
Career development is a socially constructed process involving complex interactions among different structures, forces, and systems all constituting spheres of influence. The purpose of this study was to investigate factors that influence career decisions. Eighty respondents (40 males and 40 females with mean age of 22 years) participated in the study. Results revealed that family variables of parental high expectations of children and appropriate communications within the family, as well as factors such as prestige statuses of some occupations, school curricular subjects, academic performance, teacher influences, and peer pressure had strong positive influences on career choices. Barriers to career choices identified included finance, lack of appropriate information, poor academic performance, and unsatisfactory career counseling services. Results suggest need for a better approach to career education in schools and counseling services that are adaptive to social, economic, and cultural contexts.  相似文献   
230.
This study sought to understand school-level influences on aggressive behavior and related social cognitive variables. Participants were 5106 middle school students participating in a violence prevention project. Predictors were school-level norms opposing aggression and favoring nonviolence, interpersonal climate (positive student–teacher relationships and positive student–student relationships), and school responsiveness to violence (awareness and reporting of violence and school safety problems). Outcomes were individual-level physical aggression, beliefs supporting aggression, and self-efficacy for nonviolent responses. School norms and both interpersonal climate variables had effects on all three outcomes in theorized directions. Only one of the responsiveness measures, awareness and reporting of violence, had theoretically consistent effects on all outcomes. The other, school safety problems, affected self-efficacy later in middle school. Evidence of gender moderation was generally consistent with greater influence of school-level factors on female adolescents. Discussion focuses on implications in light of previous research and intervention possibilities.  相似文献   
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