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991.
随着我国软件事业的迅速发展,软件安全问题也逐渐增多,给人们的正常生活、生产和工作带来了不同程度的危害和损失。当前软件安全问题已经成为了社会和人们关注的焦点问题,要提高软件的安全级别,还需要建立一套科学、系统的软件安全评估标准。虽然当前在基础软件服务上已经出台了一套行业标准,但是这些标准的统一性和可操作性还不够高,仍然存在很多不足之处,因此还需要探索新的安全测试标准体系,以用于指导国产通用基础软件的安全测试工作。 相似文献
992.
《Journal of Location Based Services》2013,7(4):268-284
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
993.
《Journal of Location Based Services》2013,7(1):1-4
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
994.
The dynamic compressive response of corrugated carbon-fibre reinforced epoxy sandwich cores has been investigated using a Kolsky-bar set-up. Compression at quasi-static rates up to v0 = 200 ms−1 have been tested on three different slenderness ratios of strut. High speed photography was used to capture the failure mechanisms and relate these to the measured axial compressive stress. Experiments show significant strength enhancement as the loading rate increases. Although material rate sensitivity accounts for some of this, it has been shown that the majority of the strength enhancement is due to inertial stabilisation of the core members. Inertial strength enhancement rises non-linearly with impact velocity. The largest gains are associated with a shift to buckle modes composed of 2–3 half sine waves. The loading rates tested within this study are similar to those that are expected when a sandwich core is compressed due to a blast event. 相似文献
995.
新版GB50029《压缩空气站设计规范》在站房布置、设备选型、系统流程等方面提出了许多新的规定,强调压缩空气站及其系统的节能、安全和环保。本文就有关条文进行了分析和阐述。 相似文献
996.
The use of process bus modern technology in accordance with the IEC 61850 protocol allows performing modern measurement and improving the protection automation system. It also allows for the integration and complex building of functional automation and control systems based on network devices in Ethernet technology. The paper presents measuring tests of a process bus equipment and the operation of protection functions based on measurements. 相似文献
997.
当今时代最大的环境挑战是城市和建筑对化石燃料的依赖,以及对能源、土地、水和食品安全日益增长的需求。在这一背景下,城市需向更可持续的城镇化模式转变,建筑和城市规划在这一过程中发挥主要作用。为此提出了15项绿色城市法则,以应对现存街区、区域和城市转型的挑战,并对中国低碳或无碳的未来进行了展望。 相似文献
998.
随器补偿是新生事物,优点很多,但要推行起来,一些技术问题还难以解决,主要是安装位置的选择、补偿容量的确定、以及随器补偿电容器保护问题。文章结合当前城乡电网具体情况,针对这些难点问题进行探讨,提出了解决这些难点的意见。 相似文献
999.
Despite the dangers associated with drink walking, limited research is currently available regarding the factors which influence individuals to engage in this risky behaviour. This study examined the influence of psychosocial factors upon individuals’ intentions to drink walk across four experimental scenarios (and a control condition). Specifically, a 2 × 2 repeated measures design was utilised in which all of the scenarios incorporated a risky pedestrian crossing situation (i.e., a pedestrian crossing against a red man signal) but differed according to the level of group identity (i.e., low/strangers and high/friends) and conformity (low and high). Individuals were assessed for their intentions to drink walk within each of these different scenarios. Undergraduate students (N = 151), aged 17–30 years, completed a questionnaire. Overall, most of the study's hypotheses were supported with individuals reporting the highest intentions to drink walk when in the presence of friends (i.e., high group identity) and their friends were said to be also crossing against the red man signal (i.e., high conformity). The findings may have significant implications for the design of countermeasures to reduce drink walking. For instance, the current findings would suggest that potentially effective strategies may be to promote resilience to peer influence as well as highlight the negative consequences associated with following the behaviour of other intoxicated pedestrians who are crossing against a red signal. 相似文献
1000.
煤矿地面电气系统的接地和接零的接线保护方式,与漏电保护装置配合,经实践验证,存在着盲区。为消除安全隐患,对地面三相和单相电气设备漏电保护进行改进,采用电压检测型漏电保护。该漏电保护技术经现场长期实践验证,实现了漏电超过安全电压立即断电的功能,既消除人身触电隐患,又避免漏电保护过于灵敏无法送电,同时还解决了设备正常运行时轻微漏电无法使用漏电保护装置的问题。 相似文献