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991.
Carlos Aguilar‐Ibañez Julio A. Mendoza‐Mendoza Juan C. Martinez Jose de Jesus Rubio Miguel S. Suarez‐Castanon 《国际强度与非线性控制杂志
》2015,25(12):1739-1750
》2015,25(12):1739-1750
A solution to the stabilization problem of a compact set by means of the Interconnection and Damping Assignment Passivity‐Based Control methodology, for an affine nonlinear system, was introduced. To this end, we expressed the closed‐loop system as a Port Hamiltonian system, having the property of almost all their trajectories asymptotically converge to a convenient limit set, except for a set of measure zero. It was carried out by solving a partial differential equation (PDE) or single matching condition, which allows the desired energy level or limit set E to be shaped explicitly. The control strategy was tested using the magnetic beam balance system and the pendulum actuated by a direct current motor (DC‐motor), having obtained satisfactory results. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
992.
The problem of the stability of a linear system with an interval time‐varying delay is investigated. A new Lyapunov–Krasovskii functional that fully uses information about the lower bound of the time‐varying delay is constructed to derive new stability criteria. It is proved that the proposed Lyapunov–Krasovskii functional can lead to less conservative results than some existing ones. Based on the proposed Lyapunov–Krasovskii functional, two stability conditions are developed using two different methods to estimate Lyapunov–Krasovskii functional's derivative. Two numerical examples are given to illustrate that the two stability conditions are complementary and yield a larger maximum upper bound of the time‐varying delay than some existing results. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
993.
Chiuhsiang Joe Lin Lai‐Yu Cheng Ming‐Ching Wang 《Journal of the Society for Information Display》2015,23(2):76-83
Accurate distance estimation is essential for effective user interaction with objects appearing in the virtual space. Research has shown that the distance estimation in the virtual space is not as accurate as that in the real world. The inaccuracy phenomenon is almost exclusively documented for estimating objects appearing straight ahead of the eye. A collection of the accuracy data for targets located in different angles of view in the visual field may be useful in aiding the design of user‐virtual object interaction. This study collected the object to object distance estimation accuracy for targets displayed stereoscopically. There are five horizontal and two vertical viewing angles and three depths, resulting in a total of 30 locations in the virtual space. The distance estimation for any of the 30 object pairs were performed with or without the aid of spatial cues. Significant factors influencing the accuracy and time of distance estimation were identified. Implications of the finding were discussed with respect to the stereoscopic display environment. 相似文献
994.
Relationship between age differences and display parameters on visual comfort for autostereoscopic display 下载免费PDF全文
Qin Wang Qiong‐Hua Wang Yong‐Chuan Liao 《Journal of the Society for Information Display》2015,23(2):69-75
In order to investigate the age differences for viewing autostereoscopic display, we conduct a 3 × 3 × 3 × 4 mixed design with repeated measurement experiment by using three‐dimensional (3D) video clips. Visual comfort is compared between four age groups with a questionnaire. Results of subjective evaluation are compared through the chi‐square test to check if there is a statistical significance between groups with respect to the distribution of number and proportion according to five levels of visual comfort. Then we examine age differences of visual comfort under three key display parameters including crosstalk, ambient illumination, and disparity. The results indicate that the degree of comfort varies considerably among age groups as the parameters of the display system change. Although the seniors feel most discomfort and the children get best experience in general, there is no statistical difference among the subjects when the ambient illumination is medium or disparity is large. So, it is necessary to take account of the age differences in designing 3D display parameters for enhancing visual comfort. 相似文献
995.
Evaluating the Wisdom of Strangers: The Perceived Credibility of Online Consumer Reviews on Yelp 下载免费PDF全文
This study examined the effects of review valence, the reviewer profile, and the receiver's familiarity with the platform (user/nonuser) on the perceived credibility of a review on Yelp.com and on the receiver's attitude toward the reviewed object. The results demonstrated a difference in cue‐taking between users and nonusers. For users, there was an interaction effect of 2 profile cues (number of friends and number of reviews) on competence. Users interpreted the cues in combination, whereas non‐users were not influenced by them. The friends × reviews × platform familiarity interaction indirectly affected attitude through competence. Further, review valence was positively associated with perceived credibility and attitude. The findings support and extend the social information processing theory and cue combination literature. 相似文献
996.
Neural Network and Classification Approach in Identifying Customer Behavior in the Banking Sector: A Case Study of an International Bank 下载免费PDF全文
Francisca Nonyelum Ogwueleka Sanjay Misra Ricardo Colomo‐Palacios Luis Fernandez 《人机工程学与制造业中的人性因素》2015,25(1):28-42
The customer relationship focus for banks is in development of main competencies and strategies of building strong profitable customer relationships through considering and managing the customer impression, influence on the culture of the bank, satisfactory treatment, and assessment of valued relationship building. Artificial neural networks (ANNs) are used after data segmentation and classification, where the designed model register records into two class sets, that is, the training and testing sets. ANN predicts new customer behavior from previously observed customer behavior after executing the process of learning from existing data. This article proposes an ANN model, which is developed using a six‐step procedure. The back‐propagation algorithm is used to train the ANN by adjusting its weights to minimize the difference between the current ANN output and the desired output. An evaluation process is conducted to determine whether the ANN has learned how to perform. The training process is halted periodically, and its performance is tested until an acceptable result is obtained. The principles underlying detection software are grounded in classical statistical decision theory. 相似文献
997.
Confirmation Bias in Online Searches: Impacts of Selective Exposure Before an Election on Political Attitude Strength and Shifts 下载免费PDF全文
Silvia Knobloch‐Westerwick Benjamin K. Johnson Axel Westerwick 《Journal of Computer-Mediated Communication》2015,20(2):171-187
Impacts of Internet use on political information seeking and subsequent processes have been subject to much debate. A 2‐session online field study presented online search results on political topics to examine selective exposure and its attitudinal impacts. Session 1 captured attitudes, including their accessibility. Session 2 tracked what online search results participants selected and how long they read them; participants then reported attitudes again. The study represented a 4x8x2x2 within‐subjects design: 4 topics, 8 browsing intervals each, with articles presenting opposing stances, with low versus high source credibility. Attitude‐consistent messages and messages from high‐credibility sources were preferred. Exposure to attitude‐consistent search results increased attitude accessibility and reinforced attitudes, whereas exposure to attitude‐discrepant content had opposite effects, regardless of messages' source credibility. 相似文献
998.
Safety Considerations during Different Stages of a Project Life Cycle in the Manufacturing Industry 下载免费PDF全文
At sites with multiple employers, efficient safety management is essential to ensure safety for both customers and providers. However, implementing effective safety management is challenging, particularly for companies that provide services. Provider companies encounter difficulties managing the safety of service projects for many reasons, including the variety of customers and changes in work environment. Proper preparation and integration of safety into the different project life cycle stages improves safety, but the topic has not received much attention to date. This article discusses the integration of safety considerations into service projects. Material was collected from Finnish manufacturing companies via interviews and a questionnaire. The results show that systematic methods for developing and producing services have not been adopted in the provider companies, but these are often implemented as a result of practical experience. On the other hand, providers and customers both believed that safety is taken into account during different stages of a given service project—safety issues were to some extent taken into account during the tendering and contract stages of a project, and preventive safety measures were commonly implemented during the delivery of services. However, safety performance often was not evaluated after completion of work. For this reason, companies may not have an accurate estimation of each other's safety performance in these types of multi‐employer situations. The results of this study can be used in provider organizations to help systematize safety considerations during service projects and to focus efforts on the most essential points of service project safety management. 相似文献
999.
Recently, people have begun to realize the importance of child‐resistant (CR) medicine packaging. However, most manufacturers and designers have not been able to effectively provide prevention strategies or design criteria to protect consumers. This research proposes a systematic approach to analyze CR packaging design problems and experiments to evaluate the identified design parameters and to generate the most suitable CR medicine packaging design. The design of a CR packaging bottle is used as an example to help explain the development procedure. During the development procedure, user trials, questionnaires, and children's anthropometric data on bottle opening and hand operations are analyzed. Five design parameters, specifically the cap diameter, cap height, bottle height, bottle diameter, and torsion, are identified and used to perform a Taguchi orthogonal array experimental analysis. A computer‐aided design system is also built to help generate the most suitable design alternatives. The results should assist designers in determining the most important CR design parameters and their most suitable combinations for bottle and related CR medicine packaging design. 相似文献
1000.
Frederic Marimon María del Mar Alonso‐Almeida Merce Bernardo Josep Llach 《人机工程学与制造业中的人性因素》2015,25(5):599-613
This article aims to analyze the impact of recovery on loyalty in the context of a service chain characterized by the e‐quality–perceived value–loyalty relationship. A sample of 91 out of 1,201 respondents claimed to have had service problems with an online travel agency website. A causal model to test relationships was performed using structural equations modeling, and it was found that data fit with the proposed model. The really important point to retaining customers is quality. It is not so clear that the recovery effort might affect loyalty. Our findings underpin some previous stream of literature confirming that recovery does not always affect loyalty. Although the literature has not reached a consensus in this topic, we add new elements in this debate. 相似文献