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41.
Understanding both the risk and protective factors associated with Internet Gaming Disorder (IGD) has been viewed by many in the gaming studies field as an area of research priority. The present study focused on the potential risk and protective effects of user–avatar (game figure) relationship and physical activity (PA), respectively. To address these aims, a cross-sectional and a longitudinal mixed-methods design were combined (comprising both psychological and physiological assessments). A sample of 121 emerging adult gamers (18–29 years) residing in Australia, who played massively multiplayer online games, were assessed in relation to their IGD behaviours using the nine-item Internet Gaming Disorder Scale – Short Form. Additionally, the Proto-Self-Presence (PSP) scale was used to evaluate the extent to which gamers identified with the body of their avatar. Finally, a PA monitor (Fitbit Flex) measured levels of energy consumed during real-world daily activities (active minutes). A number of linear regressions and moderation analyses were conducted. Findings confirmed that PSP functioned as an IGD risk factor and that PA acted protectively, weakening the association between PSP and IGD behaviours. Implications of these findings are discussed in relation to IGD treatment and gaming development aspects.  相似文献   
42.
多数情况下签名者只有一个人。当原始签名人无法亲自签名时,为了保证文件的有效性、防止权利过于集中,他可以委托多个人对文件进行签名和验证。方案采用量子密钥分发协议保证安全性,并利用幺正变换进行签名和验证,对签名和验证的顺序没有要求,并且签名和验证人数可以不同,提高了工作效率。正确性和安全性分析表明该方案技术实现简单,能够抵御主动和被动攻击,是一种安全的可实现量子多重代理盲签名方案。  相似文献   
43.
The aim of this study was to investigate the process of identity formation in adolescent and emerging adult regular players of massively multiplayer online role-playing games. Moreover, considering the association between involvement in these games and addiction, we took into account also the role of internet addiction. A total of 176 regular players and 239 controls, not playing massively multiplayer online role-playing games, aged between 15 and 30 years completed: the Utrecht-management of identity commitments scale, evaluating three identity processes, i.e. commitment, in-depth exploration and reconsideration of commitment; and the dependence subscale from the use abuse and dependence on internet questionnaire, in order to evaluate internet addiction. A multivariate analysis of variance evidenced that controls were higher on commitment and in-depth exploration, whereas players were higher on reconsideration of commitment and internet addiction. A structural equation model in which the three identity processes affected simultaneously internet addiction and regular involvement in massively multiplayer online role-playing games showed that reconsideration of commitment was positively associated with internet addiction and the probability to be a player, whereas in-depth exploration was negatively associated only with the probability to be a player. Being a regular player of massively multiplayer online role-playing games seems to be associated with a troubled path in the process of identity formation.  相似文献   
44.
This Letter presents an approach to using both labelled and unlabelled data to train a multilayer perceptron. The unlabelled data are iteratively pre-processed by a perceptron being trained to obtain the soft class label estimates. It is demonstrated that substantial gains in classification performance may be achieved from the use of the approach when the labelled data do not adequately represent the entire class distributions. The experimental investigations performed have shown that the approach proposed may be successfully used to train neural networks for learning different classification problems.  相似文献   
45.
Based on the design theory of soft X-ray optical multilayer thin films and magneto-optic multilayer thin films, the metal multilayer thin films for the reflection of soft X-ray and ultraviolet ray, as well as the magneto-optic multilayer thin films for the magneto-optical memories were constructed. The metal multilayer thin films and the magneto-optic multilayer thin films were deposited with magnetron sputtering. The detail of optical reflection characteristics, layered-structure, and surface and interface characteristics were studied. At the same time,the static magneto-optical characteristics and dynamic magneto-optical characteristics of the magneto-optical disk were investigated.  相似文献   
46.
Massively multiplayer online role-playing games (MMORPGs) are video games in which players create an avatar that evolves and interacts with other avatars in a persistent virtual world. Motivations to play MMORPGs are heterogeneous (e.g. achievement, socialisation, immersion in virtual worlds). This study investigates in detail the relationships between self-reported motives and actual in-game behaviours. We recruited a sample of 690 World of Warcraft players (the most popular MMORPG) who agreed to have their avatar monitored for 8 months. Participants completed an initial online survey about their motives to play. Their actual in-game behaviours were measured through the game’s official database (the Armory website). Results showed specific associations between motives and in-game behaviours. Moreover, longitudinal analyses revealed that teamwork- and competition-oriented motives are the most accurate predictors of fast progression in the game. In addition, although specific associations exist between problematic use and certain motives (e.g. advancement, escapism), longitudinal analyses showed that high involvement in the game is not necessarily associated with a negative impact upon daily living.  相似文献   
47.
用扫描电镜研究CNx/TiN涂层的摩擦磨损   总被引:5,自引:0,他引:5  
利用一台直流磁控溅射和多弧沉积设备在高速钢(HSS)衬底上沉积CNx/TiN多层复合膜,涂层的硬度超过50GPa。销-盘式摩擦试验研究了涂层的滑动摩擦性能,利用扫描电镜观察并分析了薄膜的磨损模式。结果显示涂层结构致密,附着牢固。涂层的主要磨损形式为粘着磨损、疲劳磨损和磨粒磨损。  相似文献   
48.
低温烧结铁氧体粉料的改良与开发   总被引:4,自引:0,他引:4  
介绍了低温烧结NiCuZn铁氧体性能的提高、制备新工艺和新低温烧结铁氧体粉料的开发动向。  相似文献   
49.
根据Kirchhoff-Mindlin理论要求,多层结构面板的隔声性能要考虑到复合结构中流体层和固体层之间的整个交互作用:复杂的声波传递过程中在固体和流体层之间多次反射和系统共振,通过对隔声性能与填充在两层面板之间物质密度的关系,以及对硬质物体的组合和空气层厚度的研究,来探讨评价隔声可变因素及对空腔共振约束的隔声低谷的影响.以玻璃纤维为增强材料,环氧树脂为基体,制备复合树脂板,并设计了多层复合结构,利用混响室-静音箱法对材料隔声性能进行了测试分析.研究表明:多层玻璃纤维织物增强环氧树脂复合材料呈一定的刚性,在各频率的隔声量随着复合材料厚度的增加而增加;声音传播过程中所产生的弯曲波对柔性材料隔声性能的影响远大于对刚性材料的影响.不同颗粒填充多层介质复合材料平均隔声量随材料面密度的增加而增加,与材料面密度的指数成良好的线性相关性.  相似文献   
50.
Preparation of ultrafine nickel powder by wet chemical process   总被引:1,自引:1,他引:0  
1 Introduction Driven towards smaller size, higher capacitance and lower cost, the manufacturing techniques of multilayer ceramic capacitors(MLCCs) are now undergoing a revolution characterized by the development of MLCCs with base metal internal electrod…  相似文献   
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