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81.
Musun Kwak Hanrok Chung Hyukmin Kwon Daekyung Han Yoonsun Yi Jongho Jeon Sangmun Lee Chulgu Lee Sooyeol Cha 《Journal of the Society for Information Display》2010,18(12):1072-1077
Abstract— The surface‐friction characteristics of the post‐bake temperature were compared to that of the rubbing condition on VA‐mode alignment films (AFs) using frictional force microscopy (FFM). The surface roughness and the surface frictional force increased when the temperature was elevated. However, the frictional asymmetry could not be detected by the frictional loop due to the instability of the side‐chain molecular arrangement. For the inter‐influences of the total friction and surface roughness, the density of the side chain was changed and it was intentionally rubbed for evaluation. The results showed that the total friction was higher when the rubbing was stronger and side‐chain density lower, and the surface roughness also increased in the same manner. This can be explained by the potential interaction due to the curved structure of the side‐chain surface that establishes the probe that is scanned and the top surface layer. In order to confirm the influence of the pre‐tilt angle on the tilt of the side chain, a test cell was produced under the same conditions and evaluated. The results showed that the pre‐tilt‐angle decreased according to the difference in density of the side chain and strength of rubbing after injecting liquid‐crystal (LC). 相似文献
82.
The use of the Internet in the daily activities of individuals and firms has become entrenched, and online shopping has become commonplace. However, debates about how online shopping recommendation mechanisms (OREMs) should be designed have not been completely resolved. The challenge with traditional online shopping recommendation mechanisms (TR-OREMs) is that they focus too much on quantitative factors. Thus, they ignore causal interrelationships with qualitative factors that are believed to significantly impact quantitative factors. Considering only quantitative factors and ignoring qualitative ones likely distorts the final recommendation results. Another problem with TR-OREMs is that they ignore the perceived psychological reactance of consumers against the recommended products. Such consumer reactance may be reduced when the causal interrelationships among all the quantitative and qualitative factors are analyzed and incorporated properly into the OREM. To overcome these problems, we propose a causal map – online shopping recommendation mechanisms (CM-OREMs) based on a causal map. We analyzed possible causal relationships among quantitative and qualitative factors and incorporated them in the recommendation process to reduce consumer reactance against the recommendation results. Furthermore, an elaboration likelihood model (ELM) was used to build hypotheses about how the online shopping behavior of consumers is affected by OREMs based on the proposed causal map. Specifically, the performance of the proposed OREM was empirically analyzed by gathering experiment data from qualified respondents who were asked to refer to the proposed OREM before making purchasing decisions via mobile phones. Statistical results showed that the proposed OREMs could enhance consumer decision satisfaction, decision confidence, and attitude toward the recommended products. It could also positively affect consumer purchasing intentions. The OREM had a greater effect on the high-reactance group of participants than on the low-reactance group as well as on a high-involvement product versus a low-involvement product. 相似文献
83.
Kuo-Liang Chung Soo-Chang Pei Ying-Lin Pan Wei-Ling Hsu Yong-Huai Huang Wei-Ning Yang Chyou-Hwa Chen 《Expert systems with applications》2011,38(3):1591-1601
This paper presents a gradient-based adaptive error diffusion method with edge enhancement effect while preserving the smoothness effect. The proposed method not only can modulate the threshold in halftoning dynamically but also can determine the weights of the error diffusion filter adaptively to diffuse the quantization error to neighboring pixels properly. Under six testing images, experimental results demonstrate that our proposed new error diffusion method has a good compromise between the edge enhancement effect in the halftone image and the image quality effect in the corresponding inverse halftone image when compared to the methods by Floyd–Steinberg, Eschbach and Knox, Hwang et al., Li, and Feng et al., but it has some execution-time degradation. 相似文献
84.
Feifeng Zheng Yinfeng Xu Chung Keung Poon E. Zhang Xiaoping Wu 《Computers & Industrial Engineering》2011
This paper presents a study of the problem of online deadline scheduling under the preemption penalty model of Zheng, Xu, and Zhang (2007). In that model, each preemption incurs a penalty of ρ times the weight of the preempted job, where ρ ? 0 is the preemption penalty parameter. The objective is to maximise the total weight of jobs completed on time minus the total penalty. 相似文献
85.
Autonomous topological modeling of a home environment and topological localization using a sonar grid map 总被引:1,自引:0,他引:1
This paper presents a method of autonomous topological modeling and localization in a home environment using only low-cost
sonar sensors. The topological model is extracted from a grid map using cell decomposition and normalized graph cut. The autonomous
topological modeling involves the incremental extraction of a subregion without predefining the number of subregions. A method
of topological localization based on this topological model is proposed wherein a current local grid map is compared with
the original grid map. The localization is accomplished by obtaining a node probability from a relative motion model and rotational
invariant grid-map matching. The proposed method extracts a well-structured topological model of the environment, and the
localization provides reliable node probability even when presented with sparse and uncertain sonar data. Experimental results
demonstrate the performance of the proposed topological modeling and localization in a real home environment. 相似文献
86.
87.
This paper describes the motivation, proposal, and early prototype testing of a computer tool for story visualisation. An analysis of current software for making various types of visual story is made; this identifies a gap between software which emphasises preset banks of artwork, and software which emphasises low-level construction and/or drawing. A proposal is made to fill this gap, and a prototype implementation of the proposal is described in the context of a school-based study with England and Wales’s Year 5, covering ages 9–10 years. Results from this prototype study both validate the novel proposal made and demonstrate that children are capable of manipulating characters and notional camera angles in a more complex way than most current software permits. 相似文献
88.
Recently, Wang et al. showed that two new verifier-free remote user password authentication schemes, Ku-Chen's scheme and Yoon et al.'s scheme, are vulnerable to an off-line password guessing attack, a forgery attack, and a denial-of-service attack, and then proposed an improved scheme for the real application in resource-limited environments. Unfortunately, we find that Wang et al.'s scheme is still vulnerable to an impersonation attack and an off-line password guessing attack. In addition, Wang et al.'s scheme is not easily reparable and is unable to provide perfect forward secrecy. Finally, we propose an improved scheme with better security strength. 相似文献
89.
Hsien-Chun Chung K. Lal Kummari S.J. Croucher N.J. Lawson S. Guo R.W. Whatmore Z. Huang 《Sensors and actuators. A, Physical》2009,149(1):136-142
A piezoelectric fan (piezofan) which couples a piezoelectric unimorph to an attached flexible blade is able to produce a large deflection especially at resonance. The fundamental resonant frequencies (fr) of the piezofan structures have been calculated by an analytical method and finite element modelling, and these were compared with experimental measurements. Good agreements have been obtained between them. The free tip deflection at quasi-static operation or/and the vibration amplitude at dynamic operation (A) of the piezofans have been experimentally measured. We introduce fr × A as an optimization criterion for piezofans. Optimization according to this criterion has been carried out for some piezofan configurations, such as the length and the location of the piezo patch, as well as the thickness ratio between the elastic and piezoelectric layers among a few available variations. Results show this optimization approach to be promising when compared to previously defined piezofan performance parameters such as the energy transmission coefficient and electromechanical coupling coefficient. 相似文献
90.
As mobile technology has developed, mobile banking has become accepted as part of daily life. Although many studies have been conducted to assess users’ satisfaction with mobile applications, none has focused on the ways in which the three quality factors associated with mobile banking – system quality, information quality and interface design quality – affect consumers’ trust and satisfaction. Our proposed research model, based on DeLone and McLean’s model, assesses how these three external quality factors can impact satisfaction and trust. We collected 276 valid questionnaires from mobile banking customers, then analyzed them using structural equation modeling. Our results show that system quality and information quality significantly influence customers’ trust and satisfaction, and that interface design quality does not. We present herein implications and suggestions for further research. 相似文献