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71.
Navigation systems are often followed mindlessly, as users may focus the attention on the device and not on the path. The risk of errors and bias related to the mindless adherence of the instruction is high.We suggested that a mindful walking navigation system could reduce the errors and improve the overall exploration experience. Specifically, we tested the hypothesis with an Augmented Reality system, with information directly projected on the path, in comparison with a standard device. Moreover, we tested the hypothesis that when users feel they are in control of their path, both performance and overall experience would improve. We found that both conditions increased the navigation performance and experience, decreased travel time, errors, and confusion and it increased the number of landmarks noticed.  相似文献   
72.
Beidou or COMPASS is a Chinese GNSS(global navigation satellite system).Like the GPS receiver,the COMPASS receiver also faces the challenge of choosing an optimal bandwidth to satisfy both anti-jamming capability and dynamics adaptation simultaneously.GPS/INS(inertial navigation system)deep integrated navigation system has solved this problem by fusing GPS baseband signal and INS information in a deeply coupled mode.In this study,a COMPASS B3 frequency is considered and a traditional federated GPS/INS deep integration model is used to derive a single-filter-structure based COMPASS/INS deep integration model.Besides,a double-filter-structure based COMPASS/INS deep integration model is proposed.The simulation results show a better carrier tracking performance,especially a better dynamics adaptation.The impact of IMU errors and vehicle’s dynamics on carrier tracking performance of the double-filter-structure based COMPASS/INS deep integrated navigation system are evaluated in simulated and field environments.Simulation and field test results are in accordance with the theory analysis.  相似文献   
73.
徐宝林  卢建 《山西建筑》2012,38(14):140-141
通过对国道214线结古至巴塘机场路线方案的介绍,结合山区公路的特点,对复杂路段路线方案的比选要点进行探讨,以期能对今后的山区高等级公路路线方案的比选论证有所帮助。  相似文献   
74.
Car navigation systems play a prominent role in road traffic safety and traffic regulation. However, it is necessary to improve the route guidance of car navigation systems so that they accurately and quickly recognize small differences in location. Thus, to increase the ease of understanding and safety of car navigation systems, navigation systems based on augmented reality have been proposed for providing guidance at road intersections. We are currently developing a car navigation system based on augmented reality, called AR‐Navi. We investigated designs for the display of road intersection guidance that can be easily understood even when limited information is available and proposed a “best shot” display method that does not use moving images. In addition, we implemented a prototype system that includes these methods and conducted driving experiments on public roads to evaluate the ease of understanding and safety of AR‐Navi. Using the evaluation results, we confirmed that the ease of understanding and safety is similar in the case of AR‐Navi and CG‐Navi. We also clarified the characteristics of AR‐Navi. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 180(2): 43–54, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22278  相似文献   
75.
Tourist recommendation services provide suggestions for places of interest. While the spatial structure of a tourist's visit has been successfully exploited to improve the quality of place recommendations, its temporal structure has not been taken into account so far. This is surprising because the importance of the visitors' time management is well known from tourism research. We present findings of an empirical study that sheds light on the temporal aspects of tourist exploration behaviour and discuss implications for the design of tourist-recommender systems. The data-set consists of interviews, GPS tracks and geo-referenced photo sequences from visitors of a typical Middle European destination for cultural tourism. Among the results relevant to place recommending are the following: (1) the set of places is often replanned during the visit; (2) comparing place popularity based on photo frequency and place popularity based on staying time, we found notable differences in rank ordering; and (3) the photo frequency and the detour sinuosity of the GPS tracks are decreasing slowly over time. We interpret this last finding as a time-geographic cone effect. Based on the empirical results, we discuss the implications for the design of tourist-recommending services and propose a corresponding user interface utilising a recommendation strategy that tries to counterbalance the time-geographic cone effect, that is, to decelerate the visiting experience.  相似文献   
76.
Editorial     
Mobile pedestrian navigation systems are one of the most popular Location-Based Services. In the era of Web 2.0, current mobile navigation systems often suffer from the following problems: the lack of social navigation support (utilising other people's experiences) and the challenge of making user-generated content (UGC) useful. In this article, some collective intelligence-based route recommendation methods are designed to address these problems. The proposed methods can make use of UGC (reflecting other users’ navigation experiences), and provide users with the least complex and the length-complexity-optimised (LCO) routes. Some simulations using the street network of the first district of Vienna (Austria) are designed to evaluate the proposed methods. The results show that compared to the shortest route, the collective intelligence-based routes (i.e. the least complex and the LCO routes) have a significant improvement of the route quality (with lower complexity ratings), thereby more effectively supporting users’ navigation tasks (more chances of reaching the destination, fewer mistakes made and shorter distance travelled).  相似文献   
77.
Not all of the issues impacting the success of tuberculosis (TB) treatment arise from pathogen-related disease characteristics. Nowadays, there is an increasing awareness that antibiotic treatment is not the only answer to the TB problem, promoting the search for alternative administration strategies and host-directed therapies. Among all the administration routes, being the lungs the main TB focus, inhalation is conceptually a logical solution to enhance treatment effectiveness and compliance. Nevertheless, research efforts and funding are almost entirely conveyed to conventional approaches. This review will critically evaluate the reasons constraining research in this field, providing some future perspectives. The most recent advances in inhalation approaches for TB will be discussed, either at the preclinical or clinical phase, illustrating the risk of failure and chances of success.  相似文献   
78.
结合FSAN/ITU-T标准组织的权威观点,介绍了下一代PON系统的演进原则和演进路线;着重阐述了当前NG-PON1和NG-PON2的各种热点候选技术。  相似文献   
79.
Abstract

The chaotic behaviour of the sinusoidally driven nonlinear circuit proposed by Hunt is investigated. The results are compared with those from other driven nonlinear circuits.  相似文献   
80.
This paper discusses the importance of user adaptation and software evolution in hypermedia applications, and reviews some of the most relevant approaches to both fields. The paper describes a model that has been conceived for the development, maintenance and navigation of adaptive hypermedia systems. This model, called SEMantic, systemic and evolutionary model to develop HyPermedia systems (SEM-HP), includes an incremental design process, a layered architecture and an authoring tool integrated with a navigation tool. SEM-HP architecture is composed of four subsystems, which allow the separation of aspects related to knowledge representation, presentation, navigation and user adaptation. In addition, SEM-HP has a higher layer, which acts as a meta-system and allows a consistent evolution of the elements defined in each of the four subsystems, as well as their automatic co-evolution. Regarding user interaction, four alternative ways of navigating hypermedia information are supported. Finally, the paper shows the main results of two case studies carried out with the authoring and navigation tool, JSEM-HP, at the University of Granada, Spain.  相似文献   
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