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1.
To effectively analyze the impact of continuous business interruption on the information system,an information system business affecting impact evaluation method (IBAIE) is proposed.First,we identify the main businesses of the system and quantify their vulnerability.Then,we take the businesses as the nodes of network topology and weight nodes based on the business significance.The orderly association between businesses is taken as the edges which are weighted based on the association between asset and business,and the directed weighted business network topology is obtained.Finally,the method of directed weighted network structure entropy is used to evaluate the change of system business network structure during the period from business interruption to recovery.Experiments show that this method has obvious advantages in evaluating accuracy compared to other methods,and can be applied in ensuring information system security. 相似文献
2.
文章基于对脆弱性和综合竞争力的认知和理解,构建脆弱性及综合竞争力模型,然后运用熵权-TOPSIS法和PCA法分别对中原经济区资源型城市脆弱性和综合竞争力进行测算,最后通过线性函数对两者的关系进行分析和评价。研究表明:1)从时间上来看,2006-2016年中原经济区资源型城市的脆弱性整体呈先上升后下降态势,从空间上来看,濮阳、亳州、宿州、三门峡和鹤壁的脆弱性最低;2)从时间上来看,中原经济区资源型城市的综合竞争力呈现整体上升局部下降的态势,从空间上来看,晋城、长治、淮北、洛阳的综合竞争力居前4位;3)利用线性系数分析得出,洛阳、平顶山、濮阳、南阳、宿州、亳州、邯郸和邢台的脆弱性与综合竞争力呈负相关关系,鹤壁、焦作、三门峡、晋城、运城、淮北和长治的脆弱性与综合竞争力呈正相关关系。 相似文献
3.
P Gillard L Courty S De Persis J.F Lagrange C Boulnois I Gökalp 《Journal of Energetic Materials》2018,36(3):362-374
Ignition and combustion characteristics of a low-vulnerability propellant based on RDX are studied experimentally. Ignition is obtained using a laser diode. Experiments are performed in a cylindrical closed-volume reactor for different initial pressures and initial propellant masses under nitrogen and argon surrounding atmospheres. Ignition delays, maximal overpressures, and propagation rates are obtained for different initial pressures and laser powers. Thermodynamic predictions of overpressures are also compared with experimental ones. Finally, ignition probabilities for different laser powers and gaseous atmospheres are investigated using a revised Langlie method. 相似文献
4.
随着我国城市治理中风险因素的增加,传统生鲜食品市场已成为我国大型城市治理中的脆弱环节。为避免暴发由传统生鲜食品引发的公共卫生危机,有必要对我国传统生鲜食品市场内蕴藏的公共卫生风险进行分析与评估,进而提升我国公共卫生风险治理的能力。本文以脆弱性理论为研究视角,分析传统生鲜食品市场存在的公共卫生风险,论述我国传统生鲜食品市场在自然、社会、管理以及技术系统等方面的薄弱环节。在此基础上,本文对我国传统生鲜食品市场在脆弱性系统环境下存在的潜在、次生风险提出了有针对性的治理对策。 相似文献
5.
Identifying and Verifying Vulnerabilities through PLC Network Protocol and Memory Structure Analysis
Joo-Chan Lee Hyun-Pyo Choi Jang-Hoon Kim Jun-Won Kim Da-Un Jung Ji-Ho Shin Jung-Taek Seo 《计算机、材料和连续体(英文)》2020,65(1):53-67
Cyberattacks on the Industrial Control System (ICS) have recently been
increasing, made more intelligent by advancing technologies. As such, cybersecurity for
such systems is attracting attention. As a core element of control devices, the
Programmable Logic Controller (PLC) in an ICS carries out on-site control over the ICS. A
cyberattack on the PLC will cause damages on the overall ICS, with Stuxnet and Duqu as
the most representative cases. Thus, cybersecurity for PLCs is considered essential, and
many researchers carry out a variety of analyses on the vulnerabilities of PLCs as part of
preemptive efforts against attacks. In this study, a vulnerability analysis was conducted on
the XGB PLC. Security vulnerabilities were identified by analyzing the network protocols
and memory structure of PLCs and were utilized to launch replay attack, memory
modulation attack, and FTP/Web service account theft for the verification of the results.
Based on the results, the attacks were proven to be able to cause the PLC to malfunction
and disable it, and the identified vulnerabilities were defined. 相似文献
6.
为了系统掌握大庆市城镇化的脆弱性变化规律,从城镇化脆弱性的内涵和该市实情出发,从扰动强度、敏感程度、适应能力、应对策略4个方面构建评价指标体系,利用正态云模型,对大庆市1995-2015年间的城镇化脆弱性进行测度,得到各年份目标层及准则层的脆弱性等级。结果表明:1)大庆市城镇化系统状况不断改善,城镇化整体脆弱性由高度脆弱下降为中等脆弱,4个准则层的脆弱性等级也有不同程度的下降,城镇化脆弱性明显减小。2)扰动强度与敏感程度的脆弱性有较大幅度下降,但前者稳步下降,后者2008年以来波动性明显。3)适应能力提高缓慢,脆弱性等级仅由较高脆弱降低为中度脆弱,是制约大庆市城镇化发展的首要因素。经济转型带来了应对能力的提高,但基础不稳固,且2009年以来波动明显。4)大庆市城镇化仍具有较高的脆弱性,亟需提高城镇化的适应能力与应对策略。 相似文献
7.
8.
Quantitative assessment of groundwater vulnerability using index system and transport simulation, Huangshuihe catchment, China 总被引:1,自引:0,他引:1
Groundwater vulnerability assessment has been an increasingly important environment management tool. The existing vulnerability assessment approaches are mostly index systems which have significant disadvantages. There need to be some quantitative studies on vulnerability indicators based on objective physical process study. In this study, we tried to do vulnerability assessment in Huangshuihe catchment in Shandong province of China using both contaminant transport simulations and index system approach. Transit time of 75% of hypothetical injected contaminant concentration was considered as the vulnerability indicator. First, we collected the field data of the Huangshuihe catchment and the catchment was divided into 34 sub areas that can each be treated as a transport sub model. Next, we constructed a Hydrus1D transport model of Huangshuihe catchment. Different sub areas had different input values. Thirdly, we used Monte-Carlo simulation to improve the collected data and did vulnerability assessment using the statistics of the contaminant transit time as a vulnerability indicator. Finally, to compare with the assessment result by transport simulation, we applied two index systems to Huangshuihe catchment. The first was DRASTIC system, and the other was a system we tentatively constructed examining the relationships between the transit time and the input parameters by simply changing the input values. The result of comparisons between the two index systems and transport simulation approach suggested partial validation to DRASTIC, and the construction of the new tentative index system was an attempt of building up index approaches based on physical process simulation. 相似文献
9.
AbstractThe Serbian road network includes a large portion of bridges with shallow foundations vulnerable to local scour as tragically demonstrated during the extreme flooding in May 2014. Currently, the bridge management procedures in Serbia and worldwide do not comprehensively account for a risk of bridge failure due to flooding and fail to provide sufficient information for the decision-making. Thus, a novel methodology for quantitative vulnerability assessment is suggested as a tool to identify the most vulnerable bridges in a network. Herein, the essential task is evaluation of the conditional probability of a bridge failure due to local scour in a flooding event of a certain magnitude. To apply this approach on a network level, there is a dire need to establish precise practice-ready guidelines on an optimal set of information to be used and/or collected in situ, which is discussed on an example of the Serbian bridge database. The vulnerability of a bridge to local scour may be used as a comprehensive indicator of a bridge performance in a flooding event. For a network level, the vulnerability maps with respect to flooding of different magnitudes will give road operators crucial information to apply adequate quality control plans to vulnerable bridges. 相似文献
10.
ABSTRACTResearch in UK and elsewhere has highlighted that older people are particularly vulnerable to negative health effects of overheating. This paper examines the magnitude, causes, preparedness and remedies for addressing the risk of summertime overheating in four case study residential care and extra-care settings across the UK, spanning different building types, construction and age. An interdisciplinary approach is adopted, drawing from building science and social science methods, including temperature monitoring, building surveys, and interviews with design and management teams. The findings suggest that overheating is a current and prevalent risk in the case study schemes, yet currently little awareness or preparedness exists to implement suitable and long-term adaptation strategies (e.g., external shading). There was a perception from designers to managers, that cold represents a bigger threat to older occupants’ health than excessive heat. A lack of effective heat management was found across the case studies that included unwanted heat gains from the heating system, confusion in terms of responsibilities to manage indoor temperatures, and conflicts between window opening and occupant safety. Given that care settings should provide protection against risks from cold and hot weather, design, management and care practices need to become better focused towards this goal. 相似文献