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161.
为了解决在疫情背景下传统拼车出行模式面临的交互传染风险,对疫情背景下的拼车管理进行分析,提出了将低风险及潜在风险乘客分开服务的拼车策略。在进一步考虑拼车系统应兼顾的社会效益及服务质量的基础上,构建了在满足基本额定盈利及最小化等待时长的双目标拼车应急管理优化调度模型,并给出了求解该模型的组合模拟退火算法。通过具体算例对模型的有效性进行验证,结果表明模型能够较快收敛到一个稳定值,且计算结果能够反映实际场景,说明了模型及算法的有效性。最后,通过一个仿真实验对所构建模型在病毒传播中的作用进行了分析,结果显示所构建的模型可以有效抑制拼车导致的病毒传播速度。 相似文献
162.
In this paper, we present a detailed and systematic overview of communication security aspects of Multi-Processor Systems-on-Chip (MPSoC) and the emerging potential threats on the novel Cloud-of-Chips (CoC) paradigm. The CoC concept refers to highly scalable and composable systems, assembled not only at system design-time using RTL, like traditional SoC, but also at integrated circuit (IC) packaging time thanks to 3D-IC integration technology. Practical implementation of CoC systems needs to solve the problem of scalable, configurable and secure communication not only between different functional blocks in a single ICs, but also between different ICs in a single package, and between different packages on the same or different PCBs and even between different systems. To boost such extremely flexible communication infrastructure CoC system relies on Software-Defined Network-on-Chip (SDNoC) paradigm that combines design-time configurability of on-chip systems (NoC) and highly configurable communication of macroscopic systems (SDN). This study first explores security threats and existing solutions for traditional MPSoC platforms. Afterwards, we propose SDNoC as an alternative to MPSoC communication security, and we further extend our discussion to CoC systems to identify additional security concerns. Moreover, we present a comparison of SDNoC based approach over existing approaches and discuss its potential advantages. 相似文献
163.
Through an ergonomic approach, this study aimed to evaluate whether workers involved in forest harvesting activities in rural properties are subject to the development of work-related diseases, as well as their consequences. A cross-sectional study with 267 forest workers in rural properties in the Brazilian Central region was used. The following evaluations were performed for each of the activities (felling, delimbing, tracing, manual extraction and manual loading): physical workload evaluation; biomechanical evaluation; risk of repetitive strain injuries/work-related musculoskeletal disorders; environmental noise and vibration factors, where relevant, and thermal overload through the Wetbulb Globe Temperature index. The results showed that in general the physical workload was very high, exceeding the cardiovascular load limits and adding to the need for work reorganization. All activities exposed workers to serious and imminent risks of developing injuries to the spine and lower limbs. Likewise, in general the risk of the appearance of RSI/WMSDs was very high for all activities evaluated. Such results are due to the combination of organizational work factors and factors of the work environment such as exposure to bad weather, uneven terrain, lifting and handling loads above tolerable limits, excessive noise and thermal overload. All of this allows to conclude that ergonomic risks and workers’ health hazards in forest harvesting in rural properties are latent and very worrying, and that these workers are exposed to a form of labor exploitation that invariably leads to physical and emotional exhaustion and therefore to their decreased labor capacity and useful working life. 相似文献
164.
Mosleh M. Abualhaj Abdelrahman H. Hussein Qasem M. Kharma Qusai Y. Shambour 《计算机系统科学与工程》2021,38(2):251-264
A considerable number of applications are running over IP networks. This increased the contention on the network resource, which ultimately results in congestion. Active queue management (AQM) aims to reduce the serious consequences of network congestion in the router buffer and its negative effects on network performance. AQM methods implement different techniques in accordance with congestion indicators, such as queue length and average queue length. The performance of the network is evaluated using delay, loss, and throughput. The gap between congestion indicators and network performance measurements leads to the decline in network performance. In this study, delay and loss predictions are used as congestion indicators in a novel stochastic approach for AQM. The proposed method estimates the congestion in the router buffer and then uses the indicators to calculate the dropping probability, which is responsible for managing the router buffer. The experimental results, based on two sets of experiments, have shown that the proposed method outperformed the existing benchmark algorithms including RED, ERED and BLUE algorithms. For instance, in the first experiment, the proposed method resides in the third-place in terms of delay when compared to the benchmark algorithms. In addition, the proposed method outperformed the benchmark algorithms in terms of packet loss, packet dropping, and packet retransmission. Overall, the proposed method outperformed the benchmark algorithms because it preserves packet loss while maintaining reasonable queuing delay. 相似文献
165.
Matthias Max 《突发事故与危机管理杂志》2021,29(1):2-11
Digitalization and the trend towards more short‐term and project‐oriented social engagement have had a direct impact on traditional crisis management. This societal change has supported the evolution of new types of volunteers who use low‐threshold potentials to organize and maintain support independently. Traditional institutions like the German Red Cross are challenged to deal with these rapid changes regarding their own organizational culture in relation to the new phenomenon of so‐called unaffiliated volunteers. This paper investigates how unaffiliated volunteers influence and change the organizational culture of German disaster management by analysing and reflecting organizational adaptation processes in the aftermath of the German floods in 2013, the storm events in the west of Germany in 2014 and the refugee relief mission in 2015–2016. Therefore, semi‐structured interviews with experts of the German Red Cross were held to analyse their reactions towards unaffiliated Volunteers during the Floods in 2013 and the refugee relief missions, and further focus group interviews were conducted to validate the extracted results. Findings suggest that among professionals and leading entities in the German Red Cross, a process of rethinking has emerged, recognizing the importance and necessity to open up organizational structures for the collaboration and coordination of unaffiliated volunteers. 相似文献
166.
浅析管理在信息系统安全中的必要性 总被引:1,自引:0,他引:1
在信息系统安全规划和设计中,管理作为信息系统的安全基础和信息系统各安全层面的基本要素,已经成为构建安全、可用信息系统不可或缺的必要条件。文章针对管理在信息系统安全中的作用、特点进行了论述,并结合等级保护政策提出了相应的管理建议。 相似文献
168.
针对传统的选煤厂设备管理方法存在漏检漏查、无专用仪器、数据处理繁琐等问题,提出了一种新型的选煤厂设备巡检系统的设计方案。在巡检线路及设备上安装相应的感应卡,巡检人员携带巡检仪到各点读卡,把代表该点的卡号和时间记录下来,同时完成规定的巡检和数据采集工作,然后进行下一点的巡检任务;巡检工作完成后将巡检仪的数据传送到监控计算机,由巡检数据综合信息管理软件进行处理,从而达到对巡检情况进行记录和考核的目的。实际应用表明,该系统运行稳定、功能实用。 相似文献
169.
紧凑型边界扫描技术的功能与现状 总被引:1,自引:0,他引:1
芯片一体化进程的加剧以及对功耗控制的关注日益增加,边界扫描技术面临新的挑战,这些挑战来源于调试、应用、测试等方面,紧凑型边界扫描技术对此提出了有效的解决方法;以IEEE1149.7标准以及国内外文献报道为依据,对精简引脚与增强功能边界扫描技术的测试规范进行系统的分析,重点对该技术的新功能、新特性和新应用进行详细介绍;针对符合IEEE1149.1标准的测试系统与被测系统如何升级以实现IEEE1149.7标准新功能的问题提出了相应的建议;最后总结了该技术的发展方向和应用前景。 相似文献
170.
In this article, we consider the project critical path problem in an environment with hybrid uncertainty. In this environment, the duration of activities are considered as random fuzzy variables that have probability and fuzzy natures, simultaneously. To obtain a robust critical path with this kind of uncertainty a chance constraints programming model is used. This model is converted to a deterministic model in two stages. In the first stage, the uncertain model is converted to a model with interval parameters by alpha-cut method and distribution function concepts. In the second stage, the interval model is converted to a deterministic model by robust optimization and min-max regret criterion and ultimately a genetic algorithm with a proposed exact algorithm are applied to solve the final model. Finally, some numerical examples are given to show the efficiency of the solution procedure. 相似文献