scholarly journals A Security Assessment Model for Electrical Power Grid SCADA System

2019 ◽  
Vol 8 (12S2) ◽  
pp. 763-773
Keyword(s):  
Vulnerability Assessment ◽  
Cyber Security ◽  
Large Scale ◽  
Critical Infrastructure ◽  
Security Analysis ◽  
Assessment Model ◽  
Primary Concern ◽  
Scada System ◽  
Proposed Model ◽  
The Impact

Due to the wide application of SCADA systems in national critical infrastructure, their cyber security issues and vulnerabilities have been a primary concern; whereas, the impact and consequences of cyber-attacks to these systems have the potential to result in catastrophic consequences in the physical domain. Therefore, estimating possible attack impacts and identifying system vulnerabilities are major concern in SCADA management and operations. However, it is quite difficult to plan, execute and review vulnerability analysis in critical infrastructure systems as well as in industrial control systems (such as SCADA system) due to its complexity, large-scale and heterogeneity. Consequently, a consistent domain-specific conceptual model is required to establish a generic framework for cyber security analysis to examine and investigate security threats on cyber-physical systems, the role of the entities within the system as well as system operations. The main contribution of this work is to present a multi-facets model to support cyber security analysis practices such as penetration testing, vulnerability assessment and risk analysis. The proposed model presents a common insight among different SCADA configurations, implementations and the employed protocols to handle its complexity, heterogeneous and scale. To demonstrate the usability as a proof of concept and applicability of the proposed model, the paper also presents an example illustrating how the proposed model can be employed to carry out security vulnerability assessment.

A Practical GIS-Based Reliability Estimation System for Large Scale Distribution Network

2012 ◽  
Vol 433-440 ◽  
pp. 1802-1810 ◽  
Author(s):  
Lin Guan ◽  
Hao Hao Wang ◽  
Sheng Min Qiu
Keyword(s):  
Data Storage ◽  
Large Scale ◽  
Network Reliability ◽  
Distribution Network ◽  
Reliability Assessment ◽  
Distribution Networks ◽  
Reliability Estimation ◽  
Assessment Model ◽  
Estimation System ◽  
The Impact

A new algorithm as well as the software design for large-scale distribution network reliability assessment is proposed in this paper. The algorithm, based on fault traversal algorithm, obtains network information from the GIS. The structure of distribution network data storage formats is described, facilitating automatic output of the feeders’ topological and corresponding information from the GIS. Also the judgment of load transfer is discussed and the method for reliability assessment introduced in this paper. Moreover, The impact of the scheduled outage is taken into account in the assessment model, making the results more in accordance with the actual situation. Test Cases show that the proposed method features good accuracy and effectiveness when applied to the reliability assessment of large-scale distribution networks.

RAHU Project: Assessing water security and climate change adaptation strategies in the glaciated Vilcanota-Urubamba river basin

2020 ◽  
Author(s):  
Pedro Rau ◽  
Wouter Buytaert ◽  
Fabian Drenkhan ◽  
Waldo Lavado ◽  
Juan Jimenez ◽  
...  
Keyword(s):  
Climate Change ◽  
Water Resources ◽  
Vulnerability Assessment ◽  
Water Security ◽  
Adaptation Strategies ◽  
Assessment Model ◽  
Security Assessment ◽  
Tropical Andes ◽  
The Impact ◽  
Climate Change Adaptation Strategies

<p>The Peruvian Andes are a hotspot of vulnerabilities to impacts in water resources due to the propensity for water stress, the highly unpredictable weather, the sensitivity of glaciers, and the socio-economic vulnerability of its population. In this context, we selected the Vilcanota-Urubamba catchment in Southern Peru for addressing these challenges aiming at our objectives within a particular hydrological high-mountain context in the tropical Andes: a) Develop a fully-distributed, physically-based glacier surface energy balance model that allows for a realistic representation of glacier dynamics in glacier melt projections; b) Design and implement a glacio-hydrological monitoring and data collection approach to quantify non-glacial contributions to water resources and the impact of catchments interventions; c) Mapping of human water use at high spatiotemporal resolution and determining current and future levels of water (in)security; and d) Integrate last objectives in a glacier - water security assessment model and evaluate the tool's capacity to support locally embedded climate change adaptation strategies. </p><p>The RAHU project intends to transform the scientific understanding of the impact of glacier shrinkage on water security and, at the same time, to connect to and inform policy practices in Peru. It follows a "source to tap" paradigm, in which is planned to deliver a comprehensive and fully integrated water resources vulnerability assessment framework for glacier-fed basins, comprising state-of-the-art glaciology, hydrology, water demand characterisation, and water security assessment. It includes glacio-hydrological and water resources monitoring campaigns, to complement existing monitoring efforts of our project partners and collaborators, and new remotely sensed data sets. Those campaigns will be implemented using the principles and tools of participatory monitoring and knowledge co-creation that our team has pioneered in the tropical Andes. The datasets produced by this approach, combined with existing monitoring implemented by our team and collaborators, will allow us to build an integrated water supply-demand-vulnerability assessment model for glacierized basins, and to use this to evaluate adaptation strategies at the local scale. </p><p>This research is part of the multidisciplinary collaboration between British and Peruvian scientists (Newton Fund, Newton-Paulet).</p>

scholarly journals Modeling the α-max capacity of transportation networks: a single-level mathematical programming formulation

2021 ◽  
Author(s):  
Zhaoqi Zang ◽  
Xiangdong Xu ◽  
Anthony Chen ◽  
Chao Yang
Keyword(s):  
Mathematical Programming ◽  
Travel Time ◽  
Large Scale ◽  
Transportation Network ◽  
Network Capacity ◽  
Solution Algorithm ◽  
Single Level ◽  
Capacity Model ◽  
Proposed Model ◽  
The Impact

AbstractNetwork capacity, defined as the largest sum of origin–destination (O–D) flows that can be accommodated by the network based on link performance function and traffic equilibrium assignment, is a critical indicator of network-wide performance assessment in transportation planning and management. The typical modeling rationale of estimating network capacity is to formulate it as a mathematical programming (MP), and there are two main approaches: single-level MP formulation and bi-level programming (BLP) formulation. Although single-level MP is readily solvable, it treats the transportation network as a physical network without considering level of service (LOS). Albeit BLP explicitly models the capacity and link LOS, solving BLP in large-scale networks is challenging due to its non-convexity. Moreover, the inconsideration of trip LOS makes the existing models difficult to differentiate network capacity under various traffic states and to capture the impact of emerging trip-oriented technologies. Therefore, this paper proposes the α-max capacity model to estimate the maximum network capacity under trip or O–D LOS requirement α. The proposed model improves the existing models on three aspects: (a) it considers trip LOS, which can flexibly estimate the network capacity ranging from zero to the physical capacity including reserve, practical and ultimate capacities; (b) trip LOS can intuitively reflect users’ maximum acceptable O–D travel time or planners’ requirement of O–D travel time; and (c) it is a convex and tractable single-level MP. For practical use, we develop a modified gradient projection solution algorithm with soft constraint technique, and provide methods to obtain discrete trip LOS and network capacity under representative traffic states. Numerical examples are presented to demonstrate the features of the proposed model as well as the solution algorithm.

scholarly journals Analysis methodology and assessment indices of vulnerability for asphalt pavement in cold regions

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Tongxu Wang ◽  
Xianyong Ma ◽  
Huanyu Li ◽  
Zejiao Dong
Keyword(s):  
Vulnerability Assessment ◽  
Asphalt Pavement ◽  
Frozen Soil ◽  
Assessment Model ◽  
Asphalt Pavements ◽  
Large Temperature ◽  
Cold Regions ◽  
Analysis Methodology ◽  
Geological Conditions ◽  
The Impact

AbstractAsphalt pavement structures in cold regions, which suffer from complicated environmental and geological conditions, such as large temperature difference and frozen soil, are prone to cracking, rutting, and moisture damage. However, most of the existing assessment methodologies focus on the vulnerability of the overall road traffic network, ignoring the impact of regional differences and pavements’ structural performance. To establish a highly targeted vulnerability analysis methodology for cold regional asphalt pavements, the concept of highway vulnerability and the assessment model composed of exposure, fragility, and resilience were proposed in this paper firstly. Meanwhile, the assessment indices and standards for exposure, fragility, and resilience were respectively discussed. Then, the calculation process for each index weight and vulnerability index was proposed based on AHP-fuzzy comprehensive assessment methodology. Consequently, the vulnerability grade of asphalt pavements in cold regions could be determined. Finally, the vulnerability assessment indices and methodology for cold regional asphalt pavements were illustrated and presented, providing a theoretical basis for asphalt pavement performance evaluation and vulnerability assessment serviced under cold regional climate.

scholarly journals Cylindrical Caved Space Stability Analysis for Extension Prediction of Mining-Induced Surface Subsidence

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Yang Liu ◽  
Yongxiang Ge ◽  
Congrui Zhang ◽  
Fengyu Ren ◽  
Junsheng Ma ◽  
...  
Keyword(s):  
Large Scale ◽  
Shear Failure ◽  
Surface Subsidence ◽  
Geological Hazards ◽  
Proposed Model ◽  
Iron Mine ◽  
Waste Rocks ◽  
Surface Destruction ◽  
Circular Surface ◽  
The Impact

Subsequent extension of surface subsidence after vertical caving leads to large-scale surface destruction, as well as associated geological hazards. The extension prediction for cylindrical caved space, which appears circular surface subsidence, is still an intractable issue, due to the absence of robust models. To fill such a research gap, this paper provides an analytical model for the depth and orientation where the shear failure of isotropic rocks around the caved space is firstly observed. The anisotropy of surrounding rocks is further involved to enable this model to analyze the slip failure along discontinuities in anisotropic stress state. The prediction for the extension of the surface subsidence in Xiaowanggou iron mine is conducted, and the comparison between the prediction and the observation in satellite images demonstrates the validity of the proposed model. Even though this model cannot provide a definite boundary after extension, the prediction for the orientation surface subsidence extends to contribute to mitigating the effect of geological hazards. Another contribution of this work is to provide guidance to mitigate the impact of surface subsidence on safety and environment, such as filling the interspace between large-sized caved rocks by dumping small-sized waste rocks or backfilling the caved space with waste rocks.

scholarly journals Ground Risk Assessment of UAV Operations Based on Horizontal Distance Estimation under Uncertain Conditions

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Yang Liu ◽  
Xuejun Zhang ◽  
Zhi Wang ◽  
Ziang Gao ◽  
Chang Liu
Keyword(s):  
Drag Force ◽  
Safety Assessment ◽  
Local Population ◽  
Assessment Model ◽  
Flying Height ◽  
Weather Data ◽  
Horizontal Distance ◽  
Proposed Model ◽  
Failure Point ◽  
The Impact

In this paper a ground safety assessment model is introduced based on the probability estimation of possible impact positions when unmanned aerial vehicle (UAV) crashes on the ground. By incorporating the random uncertainties during the descending process, risks associated with UAV’s ground crash are estimated accurately. The number of victims on the ground per flight hour is selected as the indicative index to evaluate the risk levels of the corresponding ground area. We mainly focus on the analysis of uncertainties that usually appear in drag coefficient which would generate a great amount of effects on the travelled horizontal distance from the failure point to the impact point on the ground, which further influences the possible impact positions. The drag force in the air, failure velocity of a UAV, and wind effects in the local area are all considered in the proposed model, as well as ground features, including sheltering effects on the ground, UAV parameter settings, and distribution of local population. Uncertainties in drag force when a UAV descends, UAV’s initial horizontal and vertical speeds at failure point, and local wind patterns are all considered as the indispensable factors in the proposed model. Especially the probability of fatality once hit by the UAV’s debris is explored to make the safety assessment more reliable and valuable. In the end, the actual UAV parameters and official historical weather data are used to estimate the risks in a real operation environment when a failure event happens at a legal flying height. Experimental results are given based on different types of UAVs and random effects in the descent. The results show that all the operations of all kinds of UAVs selected in the validation are so dangerous that the safety of people on the ground cannot be guaranteed, whose value is much bigger than the manned aircraft safety criterion 10−7.

scholarly journals Improving distributed vulnerability assessment model of cybersecurity

2018 ◽  
Vol 331 ◽  
pp. 385-393
Author(s):  
Kálmán Hadarics ◽  
Ferenc Leitold
Keyword(s):  
Vulnerability Assessment ◽  
Management Practices ◽  
Practical Method ◽  
Assessment Model ◽  
It Infrastructure ◽  
Security Risks ◽  
Additional Information ◽  
Cyber Threats ◽  
Security Software ◽  
The Impact

In the digital age more and more services and data are available over the Internet. Companies and public organizations becoming increasingly vulnerable related to hacks and cyberattacks. In order to provide successful online services, effective security initiatives and targeted protections are necessary to mitigate security risks. Effective cybersecurity more than deploying firewalls and other security software (e.g. antivirus, intrusion detection/prevention systems.). Through risk assessment and risk management practices we can identify critical parts of information systems and can transform them into security tactics. Furthermore in the Distributed Vulnerability Assessment (DVA) model three factors are identified: (1) characteristics and prevalence of cyber-threats, (2) vulnerabilities of IT infrastructure and its components and processes, (3) vulnerabilities deriving from users’ behavior. In this paper, we examine and improve our mathematical model of Distributed Vulnerability Assessment. This model can be extended for using additional information and considerations. This paper also presents a practical method which can be applied to eGovernment infrastructure and services also to reduce the impact of malware attacks of the information system.

scholarly journals Creating a mathematical model of the impact of radiation-hazardous objects on the environment during a fire.

2021 ◽  
Vol 4 ◽  
pp. 99-111
Author(s):  
V.V. Derengovsky ◽  
◽  
O.A. Kaftanatina ◽  
P.L. Kordiukov ◽  
V.A. Menshenin ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Large Scale ◽  
Radiation Condition ◽  
Automated System ◽  
Exclusion Zone ◽  
Wind Rose ◽  
Cooling Reservoir ◽  
Proposed Model ◽  
The Impact ◽  
Simplified Mathematical Model

On the basis of the new data on the assessment of the removal from fires from stocks in the combustible material and the speed of weak grassroots fires spread, the wind rose in the Chernobyl Exclusion Zone and the capabilities of the HotSpot software package, there has been developed a mathematical model of real-time assessment of the consequences of accidents that may occur in the areas of radiation-hazardous objects during fires. The proposed model was verified on the basis of comparison with the data obtained during a large-scale fire in the Chernobyl Exclusion Zone in April 2020, and the maps of the Chernobyl Exclusion Zone’s air and soil contamination with 137Cs and 90Sr were made. Using the proposed mathematical model, there has been carried out the analysis of the degree of danger that may create radiation-hazardous objects in case of fire directly on the territory of their location. In the paper, there are also considered the examples of the sanitation point (SP) «Rudnia-Veresnia», SP «Rozsokha» and the «Point of vehicle washing near the ChNPP cooling reservoir» in comparison with the current contamination of air and soil around these facilities with radionuclides. The results of the conducted analysis have been used to make a conclusion about the insignificant impact on the environment of the Chernobyl Exclusion Zone compared to the current level of air pollution and the surface of its territory. Estimates of radiation exposure from SP «Rudnia-Veresnia», SP «Rozsokha» and the «Point of vehicle washing near the ChNPP cooling reservoir» to the environment have been obtained with the help of a simplified mathematical model. These data have a significant correlation with the actual data obtained in April 2020 (during a large-scale fire in the Chernobyl Exclusion Zone) in the areas of location of the points of the automated system of radiation condition control, and places of work, temporary and permanent stay of the personnel and the population. Therefore, the created simplified mathematical model can also be used to assess the radiation impact on the environment in the implementation of emergencies of various kinds at other numerous radiation-hazardous facilities of the ChEZ.

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