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61.
Eye-tracking technology was used to examine Internet search result evaluation strategies adopted by sixth-grade students (N?=?36) during ten experimental information search tasks. The relevancy of the search result’s title, URL, and snippet components was manipulated and selection of search results as well as looking into probabilities on the search result components was analysed. The results revealed that during first-pass inspection, students read the search engine page by first looking at the title of a search result. If the title was relevant, the probability of looking at the snippet of the search result increased. During second-pass inspection, there was a high probability of students focusing on the most promising search result by inspecting all of its components before making their selection. A cluster analysis revealed three viewing strategies: half of the students looked mainly at the titles and snippets; one-third with high probability examined all components; and one-sixth mainly focused on titles, leading to more frequent errors in search result selection. The results indicate that students generally made a flexible use of both eliminative and confirmatory evaluation strategies when reading Internet search results, while some seemed to not pay attention to snippet and URL components of the search results.  相似文献   
62.
Changes in operational environment of the process industry such as decreasing selling prices, increased competition between companies and new legislation, set requirements for performance and effectiveness of the industrial production lines and processes. For the basis of this study, a life cycle profit (LCP) model of a pulp process was constructed using different kind of process information including chemical consumptions and production levels of material and energy flows in unit processes. However, all the information needed in the creation of relevant LCP model was not directly provided by information systems of the plant. In this study, neural networks was used to model pulp bleaching process and fill out missing information and furthermore to create estimators for the alkaline chemical consumption. A data-based modelling approach was applied using an example, where factors affecting the sodium hydroxide consumption in the bleaching stage were solved. The results showed that raw process data can be refined into new valuable information using computational methods and moreover to improve the accuracy of life cycle profit models.  相似文献   
63.
Payments are the locomotive behind any business domain. It has been predicted that mobile payments will become one of the most successful mobile services, and the security of payments is an important requirement. However, it is difficult to strongly authenticate mobile users remotely and provide an adequate level of non-repudiation of transactions. In this article, we argue that a nationwide public-key infrastructure supported by governmental bodies can be used in a mobile payment system. Not only does it provide strong security, but it also makes the system open to any mobile user, merchant, or financial service provider. Two payment protocols are described: one for virtual point-of-sale payments, and one for vending machine payments. We argue that such a system can be implemented using open development platforms, and its performance is adequate for enabling swift transactions. A prototype of a system which accepts virtual point-of-sale payments is implemented, and its performance and usability are evaluated.  相似文献   
64.
A method for bone strain estimation is examined in this article. The flexibility of a single bone in an otherwise rigid human skeleton model has been studied previously by various authors. However, in the previous studies, the effect of the flexibility of multiple bones on the musculoskeletal model behavior was ignored. This study describes a simulation method that can be used to estimate the bone strains at both tibias and femurs of a 65-year-old Caucasian male subject. The verification of the method is performed by the comparison of the results with other studies available in literature. The results of the study show good correlation with the results of previous empirical studies. A damping effect of the flexible bones on the model is also studied in this paper.  相似文献   
65.
Several studies indicate that virtual reality (VR) systems are useful for end-user participation in an environmental design process. However, these systems can be costly and thus support for the decision whether to invest in a VR of some type is useful. This study presents a novel method for analysing the usefulness of a VR system for the purpose of end-user participation. We collected qualitative end-user opinion data in the real environment and then contrasted this data with the capabilities of a VR system. Additionally, to better understand the capabilities of the VR used, we examined how the end-users perceive the used virtual environment, which in this case was CAVE, an immersive VR system where projectors are directed to the walls of a room-sized cube. In this way, we analysed whether the same functions and elements identified by end-users on the actual wards could also be evaluated in the CAVE. Eleven nurses and 11 patients participated in the study by evaluating a bathroom and/or four patient rooms modelled by the CAVE and the actual hospital wards. The CAVE was convenient for evaluating most issues identified by the study participants in the actual hospital wards, i.e. aesthetics; correct location of equipment, supplies and materials; distraction by or the good companion of other patients as well as window position and size and living/workspace. However, it was not possible to evaluate with full certainty the possibilities for bracing against grab bars or other objects in the VR, and this was found to be relevant to the independent functioning of patients with limited mobility. Also, due to the relatively low luminance levels of projectors, evaluations regarding lighting were considered unreliable. Moreover, end-users were not always certain about the sizes and sufficiency of space in the CAVE. Solutions to overcome these limitations were proposed.  相似文献   
66.
Moving threads is a new kind of approach for multicore processor architectures. Traditionally, each thread stays in the core where it is created, and data is moved from the main memory via caches to each core and thread. In the moving threads approach, each core can access only a certain portion of the main memory via its local memory block, and thus extremely lightweight threads are moved between the cores. As a consequence, all kinds of cache coherence problems and need for read reply messages are eliminated. Also Lamport’s sequential consistency of shared memory multiprocessor systems is achieved for free. In this paper, we propose a processor architecture (MTPA) for the moving threads paradigm. We describe the overall structure, operation, instruction set, and thread management mechanism as well as evaluate the proposed architecture with different functional unit settings with simulations and give early silicon area and power consumption estimates.  相似文献   
67.
In this study, we explored how stereoscopic depth affects performance and user experience in a mobile device with an autostereoscopic touch display. Participants conducted a visual search task with an image gallery application on three layouts with different depth ranges. The task completion times were recorded, and the participants were asked to rate their experiences. The results revealed that the image search times were facilitated by a mild depth effect and that too great a depth slowed search times and decreased user-experience ratings.  相似文献   
68.
The aim of this study was to examine the response of the autonomic nervous system in younger (mean age 31 yrs, n=14) and older (mean age 54 yrs, n=14) healthy female teachers during work periods of perceived high and low stress. In the younger participants, heart rate, cortisol excretion rate and psychosomatic symptoms were significantly higher during the high work stress period. The older participants experienced no decrease in their heart rate and cortisol excretion during the low stress period and they exhibited no significant decrease in blood pressure after the work in the evening during both periods. It may be concluded that the recovery from the stress in the older teachers was insufficient particularly in view of their elevated diastolic blood pressure during the low work stress period. Ergonomic and individually tailored measures in terms of work time control, specific relaxation techniques, and a part-time retirement may improve the stress management of older teachers.  相似文献   
69.
This paper presents a reduction from the problem of solving parity games to the satisfiability problem in propositional logic (SAT). The reduction is done in two stages, first into difference logic, i.e. SAT combined with the theory of integer differences, an instance of the SAT modulo theories (SMT) framework. In the second stage the integer variables and constraints of the difference logic encoding are replaced with a set of Boolean variables and constraints on them, giving rise to a pure SAT encoding of the problem. The reduction uses Jurdziński?s characterisation of winning strategies via progress measures. The reduction is motivated by the success of SAT solvers in symbolic verification, bounded model checking in particular. The paper reports on prototype implementations of the reductions and presents some experimental results.  相似文献   
70.
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