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131.
As the commonest part of social networks, sharing images in social network not only provides more information, but also gives more intuitive view than text. However, images also can leak out information more easily than text, so the audit of image content is particularly essential. The disclosure of a tiny image, which involves sensitive information about individual, society even the state, may trigger a series of serious problems. In this paper, we design a kind of intelligent image firewall to detect and filter sensitive or privacy images. Two different approaches of the firewall are proposed. In the first approach, we propose an image firewall based on joint sparse representation, which can provide accurate and robust privacy prediction, and also can provide rich spatial relationship information. In the second approach, we propose a method based on the deep learning (Faster RCNN), which can predict the privacy relationships or actions (like kiss, hug and hand in hand) among the persons of an image. Experimental results show the effectiveness of the two kinds of approaches.  相似文献   
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With an increasingly aging population, more work is needed to identify factors which may promote the maintenance of normal cognitive functioning. The current study tested the concurrent association between sense of purpose in life and the cognitive variables of episodic memory, executive functioning, and composite cognitive functioning in adults (N = 3489, Mage = 56.3 years, SD = 12.27, Range = 32–84 years) from the Midlife in the United States study (MIDUS). Correlational analyses suggested that purpose in life was associated with higher scores for memory, executive functioning, and overall cognition. Bootstrapping tests of moderation found no evidence for a moderating effect of age on purpose and the cognitive variables. Future studies should attempt to explain the mechanisms behind this relationship and explore the potential for interventions to promote healthy cognitive and purposeful aging.  相似文献   
134.
Research suggests a reciprocal relationship between late-life anxiety and cognition, particularly attention and executive functions. Whereas evidence supports a conceptual distinction between cognitive and somatic dimensions of anxiety, their differential relationship with cognitive outcomes has not been examined, particularly on tests of attention/executive functions that rely on processing speed. Study goals were threefold: (a) to describe levels of overall, cognitive, and somatic anxiety in a sample of older adults without dementia, (b) to determine if overall anxiety is associated with performance on select measures of attention/executive functions that rely on processing speed, and (c) to determine if a differential relationship exists between cognitive and somatic anxiety and cognitive performance. Participants were 368 community-dwelling older adults. Results showed that elevated levels of somatic, but not cognitive anxiety were associated with poorer performance across measures. Findings suggest that the nature of anxiety symptoms may have important implications for cognitive performance in older adults.  相似文献   
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一些研究发现海洛因成瘾者奖赏失调表现为:对海洛因相关线索的注意偏向、渴求感增加,对金钱奖赏表现出"即时收益优先"的高风险决策模式和对长时收益的敏感性降低。另一些研究发现海洛因成瘾者的执行功能存在障碍。奖赏失调和执行功能障碍在成瘾物质使用的维持和复吸中起着重要作用。双重竞争模型认为奖赏和执行功能的交互作用决定着行为的结果,但是奖赏对海洛因成瘾者执行功能的影响机制还不清楚。因此,拟使用事件相关电位技术来考察海洛因相关线索和金钱奖赏对不同戒断期成瘾者执行功能的影响机制,短期(1~3个月)、长期(18个月以上)海洛因戒断者和健康对照组被比较。这不仅有助于构建完善的成瘾理论体系,还有助于确定临床戒断后复吸的风险因素和不同戒断期的治疗目标。  相似文献   
137.
蒋多  何贵兵 《心理科学进展》2017,(11):1992-2001
决策是指决策者对将产生不同结果的多个备择方案的评估与选择。无论决策结果涉及的是金钱、健康、环境或是其他事物,它们都同时具有多重属性,如发生的概率,发生的时间,发生的地点,发生在谁身上等,这些属性会和结果量一起影响人们对结果效用的评价和对备择方案的选择。以往有关风险决策、跨期决策和社会决策的理论分别探究结果的概率属性、时间属性和人际属性如何与结果量一起共同决定人们的效用评估与选择,并提出了各自不同的决策模型。然而,心理距离理论则认为,决策结果的概率、时间、空间、人际等属性本质上都可被表征为结果在决策者心中的心理距离。这意味着风险、跨期和社会决策模型有可能经由心理距离而得以统一。近几年来,众多研究围绕这一思想开展了一系列实验研究,分析了各种心理距离的同质性,探索了基于心理距离的心理折扣现象及其规律,探讨了时间、概率、人际、空间距离对个体决策的影响。在此基础上,未来研究还应更加重视对多特征决策的研究,探索心理距离之间的替换率和通币问题,探究心理距离的本质及其整合方式,以期形成统一的决策理论模型。  相似文献   
138.
针对面孔认知偏好的类别化-个体化模型,探讨该模型中的知觉经验、加工方式和动机水平对本龄效应的影响。结果表明增加对异龄面孔的知觉经验、个体化加工异龄面孔及提高加工异龄面孔的动机都能有效改善对异龄面孔的再认,减少本龄效应量。这说明本龄效应遵循类别化-个体化模型,且在类别化-个体化模型中本龄效应与本族效应加工原理相仿。。  相似文献   
139.
Executive function is a broad construct that encompasses various processes involved in goal‐directed behaviour in non‐routine situations (Banich, 2009). The present study uses a sample of 560 5‐ to 16‐year‐old twin pairs (M = 11.14, SD = 2.53): 219 monozygotic twin pairs (114 female; 105 male) and 341 dizygotic twin pairs (136 female, 107 male; 98 opposite sex) to extend prior literature by providing information about the factor structure and the genetic and environmental architecture of the Behavior Rating Inventory of Executive Function (BRIEF; Gioia et al., 2000, Child Neuropsychol., 6, 235; Gioia et al., 2000, Behavior rating inventory of executive function, Lutz, FL: Psychological Assessment Resources), a multifaceted rating scale of everyday executive functions. Phenotypic results revealed a 9‐scale, 3‐factor model best represents the BRIEF structure within the current sample. Results of the genetically sensitive analyses indicated the presence of rater bias/contrast effects for the Initiate, Working Memory, and Task‐Monitor scales. Additive genetic and non‐shared environmental influences were present for the Initiate, Plan/Organize, Organization of Materials, Shift, and Monitor and Self‐Monitor scales. Influences on Emotional Control were solely environmental. Interestingly, the aetiological architecture observed was similar to that of performance‐based measures of executive function. This observed similarity provided additional evidence for the usefulness of the BRIEF as a measure of ‘everyday’ executive function.  相似文献   
140.
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