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91.
Homogeneous and nano-sized BPNT [(Ba1-xPbx)Nd2Ti5O14] powders were prepared under various hydrothermal conditions. Crystallinity and homogeneity of the synthetic powders were
investigated. The microwave dielectric properties of the filters prepared with hydrothermal powders were compared with those
of the filters prepared with conventional powders. The microwave dielectric properties of the filter prepared with the hydrothermal
powders were also better than those of the filter manufactured with the conventional powders. The dielectric constant, quality
constant and temperature coefficient of resonance frequency of hydrothermally prepared filter under optimum condition and
measured at 3.5 GHz around were about 93, 6067 and 0 ppm/°C, respectively. 相似文献
92.
The relationship between video gameplay, video game genre preference, personality, and GPA was investigated in an online correlational study with university students. In addition to administering self-report measures of GPA and personality, we asked three different questions regarding styles of video gameplay. The first asked the average time spent playing video games per week (habitual players), the second asked the total time spent playing favorite video games (selective players), and the third asked the number of different video games played in a year (diverse players). Students who were medium in selective player style (spent 11-50 h) had significantly higher GPAs than students low on selective player style (spent 0-10 h). Students high on habitual playing style (7 or more hours a week) showed significantly lower levels of Conscientiousness compared to students low on habitual playing style (0-1 h a week). Students who were high on the diverse style (i.e., 7 or more games played a year) showed significantly higher Openness scores than students low on the diverse style (0-3 games a year). Finally, several notable relations were found between video game genre preference, GPA, and personality. Results are discussed in terms of the positive implications of video gameplay on academic performance. 相似文献
93.
Failure to establish agreed-upon criteria by which to measure and identify online video game addiction has resulted in a lack of reliable evidence of the actual percentage of individuals who are pathologically dependent. Building upon prior research, the present study sought to better determine the magnitude of pathological online video game play using a distinction between core and peripheral criteria for behavioral addiction. Preferences and perceptions towards online video games and addiction were also examined to better understand players’ habits. A questionnaire was administered to 1332 South Korean students across 11 high schools and 1 middle school in an area surrounding the capital of Seoul. Using a monothetic and a polythetic classification system, findings showed rates ranging between 1.7% and 25.5%, with a 2.7% addiction rate when distinguishing core from peripheral criteria. These results may suggest that online video game addiction rates in intense gaming cultures such as South Korea are not as high as otherwise believed. The findings will be of assistance to educators, policymakers, clinicians, and researchers in understanding the challenges in deriving meaningful video game addiction prevalence rates, and thus being able to better separate reality from conjecture with regard to the notion of pathological game play. 相似文献
94.
Social media services such as YouTube and Flickr have become online necessities for millions of users worldwide. Social media are online services that enable users to share contents, opinions, and perspectives that support communication with other users. Social media places an emphasis on the shared experience between users, which we call co-experience. However, the online characteristics of social media increase psychological distance between users, which, in turn, results in a decrease in the quality of co-experience. Hence, as the goal of this study, we theoretically modeled and empirically verified the antecedents and user experience-based consequences of psychological distance in a social media-enhanced real-time streaming video service. In order to reduce psychological distance, we introduced two system elements: inhabited space (the degree of being situated in context and in a meaningful place) and isomorph effects (the degree of preserving the structure of a user’s actions). We constructed a social media-enhanced real-time streaming video service prototype and conducted a field experiment with actual social media users. The prototype, which streamed a live baseball game, enabled users to simultaneously view the game from remote locations and to interact with each other through cheering tools. The results indicate that inhabited space and isomorph effects reduce psychological distance between users, and this, in turn, enhances co-experience. This paper ends with theoretical as well as practical implications of the study. 相似文献
95.
Currently, embedded systems have been widely used for ubiquitous computing environments including digital setup boxes, mobile
phones, and USN (Ubiquitous Sensor Networks). The significance of security has been growing as it must be necessarily embedded
in all these systems. Up until now, many researchers have made efforts to verify the integrity of applied binaries downloaded
in embedded systems. The research of problem solving is organized into hardware methods and software-like methods. In this
research, the basic approach to solving problems from the software perspective was employed. From the software perspective,
unlike in the existing papers (Seshadri et al., Proc. the IEEE symposium on security and privacy, 2004; Seshadri et al., Proc. the symposium on operating systems principals, 2005) based on the standardized model (TTAS.KO-11.0054.
2006) publicized in Korea, there is no extra verifier and conduct for the verification function in the target system. Contrary
to the previous schemes (Jung et al. , 2008; Lee et al., LNCS, vol. 4808, pp. 346–355, 2007), verification results are stored in 1 validation check bit, instead of storing signature value for application binary files
in the i-node structure for the purpose of reducing run-time execution overhead. Consequently, the proposed scheme is more
efficient because it dramatically reduces overhead in storage space, and when it comes to computing, it performs one hash
algorithm for initial execution and thereafter compares 1 validation check bit only, instead of signature and hash algorithms
for every application binary. Furthermore, in cases where there are frequent changes in the i-node structure or file data
depending on the scheme application, the scheme can provide far more effective verification performance compared to the previous
schemes. 相似文献
96.
Seok-Ho Yoon Jung-Hwan Shin Sang-Wook Kim Sunju Park Jae Bum Lee 《Information Sciences》2012,184(1):215-229
In the blogosphere, there exist posts relevant to a particular subject and blogs that show interest in the subject. In this paper, we define a set of such posts and blogs as a blog community and propose a method for extracting the blog community associated with a particular subject. The proposed method is based on the idea that the blogs who have performed actions (e.g., read, comment, trackback, scrap) to the posts of a particular subject are the ones with interest in the subject, and that the posts that have received actions from such blogs are the ones that contain the subject. The proposed method starts with a small number of manually-selected seed posts containing the subject. Then, the method selects the blogs that have performed actions to the seed posts over some threshold and the posts that have received actions over some threshold. Repeating these two steps gradually expands the blog community. This paper presents various techniques to improve the accuracy of the proposed method. The experimental results show that the proposed method exhibits a higher level of accuracy than the methods proposed in prior research. This paper also discusses business applications of the extracted community, such as target marketing, market monitoring, improving search results, finding power bloggers, and revitalization of the blogosphere. 相似文献
97.
Automatic Real-Time Video Matting Using Time-of-Flight Camera and Multichannel Poisson Equations 总被引:1,自引:0,他引:1
Liang Wang Minglun Gong Chenxi Zhang Ruigang Yang Cha Zhang Yee-Hong Yang 《International Journal of Computer Vision》2012,97(1):104-121
This paper presents an automatic real-time video matting system. The proposed system consists of two novel components. In
order to automatically generate trimaps for live videos, we advocate a Time-of-Flight (TOF) camera-based approach to video
bilayer segmentation. Our algorithm combines color and depth cues in a probabilistic fusion framework. The scene depth information
returned by the TOF camera is less sensitive to environment changes, which makes our method robust to illumination variation,
dynamic background and camera motion. For the second step, we perform alpha matting based on the segmentation result. Our
matting algorithm uses a set of novel Poisson equations that are derived for handling multichannel color vectors, as well
as the depth information captured. Real-time processing speed is achieved through optimizing the algorithm for parallel processing
on graphics hardware. We demonstrate the effectiveness of our matting system on an extensive set of experimental results. 相似文献
98.
This study develops a new design method called the constraint force design method, which allows topology optimization for planar rigid-body mechanisms. In conventional mechanism synthesis methods, the kinematics of a mechanism are analytically derived and the positions and types of joints of a fixed configuration (hereafter the topology) are optimized to obtain an optimal rigid-body mechanism tracking the intended output trajectory. Therefore, in conventional methods, modification of the configuration or topology of joints and links is normally considered impossible. In order to circumvent the fixed topology limitation in optimally designing rigid-body mechanisms, we present the constraint force design method. This method distributes unit masses simulating revolute or prismatic joints depending on the number of assigned degrees of freedom, analyzes the kinetics of unit masses coupled with constraint forces, and designs the existence of these constraint forces to minimize the root-mean-square error of the output paths of synthesized linkages and a target linkage using a genetic algorithm. The applicability and limitations of the newly developed method are discussed in the context of its application to several rigid-body synthesis problems. 相似文献
99.
100.
Hot band annealing is known to be a prerequisite for good magnetic properties irrespective of manufacturing methods in grain‐oriented Fe‐3 wt.% Si electrical steels. In this study, the effects of hot band annealing on magnetic properties were investigated in 3% grain‐oriented electrical steels of low soluble AI contents and one‐stage cold rolling. Microstructure and precipitate distribution were compared with hot band annealing conditions. Secondary recrystallization behaviour with hot band annealing condition was also discussed. 相似文献