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991.
The potential benefits of thumb-based touch interaction have not been fully exploited due to its usability problems and performance deterioration. Despite the well-known problems, mobile phone users often prefer thumb-based input method in their daily context of use. Without understanding input performance under realistic variability, design solutions may not address the problems adequately. This research aims to evaluate performance of one-handed thumb-based input compared to cradled finger-based input for the large number of users and varying task conditions. By investigating performance under a range of user- and task-variability, common patterns can be identified to help infer realistic performance in context of use. For this experiment, 259 participants were recruited balanced on gender and age. They performed user testing of moving an icon on a mobile touch-screen. Overall, the one-handed thumb input showed a 30% reduction in throughput compared to the cradled finger-based input, with significant reduction in speed and accuracy. Reduced throughput is attributed to inaccuracy rather than speed. In addition, the partial effects of touch position, dragging direction, and target size were investigated and quantified. In conclusion, performance could maintain constant throughput only for the finger-based input of limited task conditions, when realistic variability was introduced. Also, high variance of throughput for the thumb-based input led to poor conformity to Fitts’s law. The findings have implications for design of thumb-based touch interface to offset performance reduction and characterizing performance measure for thumb-based input method. 相似文献
992.
Hyung Nam Kim Craig Garfield Young Seok Lee 《International journal of human-computer interaction》2013,29(1):44-54
Little is known about how differently mothers and fathers of very low birth weight (VLBW) infants use information and communication technology (ICT), especially during the vulnerable transition from the neonatal intensive care unit (NICU) to home. This study aims to qualitatively compare and contrast the two groups’ usage of technology. In-depth, semistructured phone interviews were conducted with 25 parents of 16 VLBW infants who had been hospitalized in the NICU. Grounded theory facilitated the understanding of interview data. This article discusses the patterns that emerged around the use of ICT between the two groups and discusses the implications for health information seeking, privacy and misinformation, online social networking, learning technology, choosing a health care provider, and health care communication. 相似文献
993.
Gilok Choi Hyewon Chung Yoonsook Kim 《International journal of human-computer interaction》2013,29(6):399-405
Common stereotypes of virtual game or community users are often portrayed as young and socially inept male addicts. Recent studies, however, defy many of the common prejudices about game or community users. As an extension of recent research, this study looks at gender differences in Virtual Worlds and finds that female users are actually a driving force behind the recent success of online communities. The study results indicate that female users more actively participate in social life, information seeking, and building activities in Virtual Worlds than their male counterparts. Similarly, female users have greater appreciation for the value of Virtual Worlds, although both male and female users recognize Virtual Worlds as a highly useful entertainment tool. 相似文献
994.
Hong‐Ming Zhan Zheng Xu Yong‐Can Wang Li‐Feng Lin Ming Chen Woong Kim Dan Wang Xi‐Bin Shao Seong‐Kyu Lee 《Journal of the Society for Information Display》2013,21(3):137-141
A type of fast response time (RT) liquid crystal (LC) was developed to adopt in fringe‐field switching (FFS) mode for shutter glass 3D display device, the average gray to gray level (GTG) RT can reduce from 7.43 ms to 4.48 ms at a refreshing rate of 60 Hz, and the transmittance can increase by 15.4% compared with conventional LC based on the same cell gap. Meanwhile, the correlation among optical efficiency, correlative color temperature (CCT) of module and retardation of LC for FFS mode was studied. Transmittance is proportional to the retardation of LC; however, the CCT is inversely proportional to the retardation. The fast response LC can keep almost the original optical efficiency and CCT. 相似文献
995.
996.
Yong Hee Lee Soon Seok Kim Sea Il Park Jong Hyuk Park 《Multimedia Tools and Applications》2013,63(1):45-61
In order to remove physiological artefacts and gain the improved evoked potentials, we propose a filtering method using the multi-resolution wavelet transform. The wavelet transform is repeatedly performed until all resolution levels are obtained. It decomposes the measured evoked potentials into scale coefficients corresponding to low frequency components and wavelet coefficients corresponding to high frequency components. In the wavelet domain, artefacts are dispersed mainly at the wavelet coefficients rather than the scaling coefficients. Thus, when the inverse wavelet transform is performed, this method shrinks the wavelet coefficients to reduce artefacts with shrinkage functions. By repeatedly performing the inverse wavelet transform, an evoked potential having the reduced artefacts and background noise is obtained. In this study, quantitative evaluation with simulation data and actual clinical data were conducted. As a result, characteristic peaks of evoked potential could be gained removing background EEG and artefacts using suggested shrinkage function. It was improved more than 0.2–1.6Db compared to the conventional averaging method. Also, the system for measuring and analyzing evoked potentials using DSP is implemented. 相似文献
997.
Genetic algorithm-based motion estimation schemes play a significant role in improving the results of H.264/AVC standardization efforts when addressing conversational and non-conversational video applications. In this paper, we present a robust motion estimation scheme that uses a noble genetic trail bounded approximation (GTBA) approach to speed up the encoding process of H.264/AVC video compression and to reduce the number of bits required to code frame. The proposed algorithm is utilized to enhance the fitness function strength by integrating trail information of motion vector and sum of absolute difference (SAD) information into a fitness function. Experimental results reveal that the proposed GTBA resolves conflict obstacles with respect to both the number of bits required to code frames and the execution time for estimation. 相似文献
998.
IPTV, a technological convergence that combines communication and broadcasting technologies, delivers customized, interactive TV content and other multimedia information over wired and wireless connections. Providing secure access to IPTV services calls for authentication, without proper and secure authentication mechanisms, an individual impersonating a subscriber could steal a service. This paper proposes a new authentication protocol to authenticate IPTV users. The authors based the proposed protocol, a hybrid authentication protocol providing lightweight, personalized user authentication, on RFID (radio-frequency identification) and USIM (Universal Subscriber Identity Module) technologies. In the proposed protocol, USIM performs highly personalized authentication, and the authenticated subscriber’s RFID tags can have a temporary authority to execute authentication. These RFID tags become Agent Tags authorized to authenticate subscribers. Agent Tags identify and authenticate themselves to RFID readers in the set-top box, thus, simplifying the authentication process. 相似文献
999.
We design and implement a personalized target advertisement (PTA) system in IPTV using ontology-based semantic relations between IPTV program and advertisement. In the PTA system, we focus on the development of an ontology reasoning technique of improving advertisement recommendation ability and exploiting efficient information reuse. For this purpose, we first build the IPTV program ontology and viewer profiling ontology based on the IPTV program and viewers’ content consumption behavior, using OWL (Web Ontology Language) standardized by W3C. We then classify each viewer into his/her corresponding reference group using a similarity metric. After that, we define the semantic relations between advertisement and shopping products consumed by the prototype through shopping sites in IPTV. Based on these semantic relations, we infer the preferred advertisements for each viewer through our reasoning process. In the experimental section, we demonstrate a prototype of our system and the algorithm of the PTA system using various cases. 相似文献
1000.
Automated audio segmentation and classification play important roles in multimedia content analysis. In this paper, we propose an enhanced approach, called the correlation intensive fuzzy c-means (CIFCM) algorithm, to audio segmentation and classification that is based on audio content analysis. While conventional methods work by considering the attributes of only the current frame or segment, the proposed CIFCM algorithm efficiently incorporates the influence of neighboring frames or segments in the audio stream. With this method, audio-cuts can be detected efficiently even when the signal contains audio effects such as fade-in, fade-out, and cross-fade. A number of audio features are analyzed in this paper to explore the differences between various types of audio data. The proposed CIFCM algorithm works by detecting the boundaries between different kinds of sounds and classifying them into clusters such as silence, speech, music, speech with music, and speech with noise. Our experimental results indicate that the proposed method outperforms the state-of-the-art FCM approach in terms of audio segmentation and classification. 相似文献