Design Of Protection System Research Articles

Probabilistic impact assessment of lightning strikes on power systems incorporating lightning protection design and asset condition

Lightning strikes may result in widespread power outages with long supply interruption times and severe impacts to economy and society. To prevent this from happening now and in the future, power system planning and operation practices must be revisited so that the probability of outages caused by lightning strikes can be reduced. In this context, this article presents a probabilistic framework for impact assessment of lightning strikes on the grid which investigates power system exposure to lightning strikes. This new framework incorporates information about failure rates attributed to lightning protection system design and asset condition together with the probability of lightning activity over time for a probabilistic impact assessment of lightning strikes on the grid. Notably, the probability of lightning activity is conditioned by information about weather patterns and seasons obtained through collaboration with the Met Office. Furthermore, it is demonstrated in the reduced 29-bus Great Britain transmission system model with weather data collected from 2010 to 2019 and validated against historical fault data recordings provided by the National Grid’s Transmission System Performance Reports and by the National Fault Interruption Reporting Scheme. Therefore, the framework is envisaged to assist power system planners to investigate best design and maintenance practices and grid modernization interventions and power system operators to deploy smart operational measures that reduce the probability of power outages caused by lightning strikes.

Temporally and Spatially Resolved Reflected Overpressure Measurements in the Extreme Near Field.

The design of blast-resistant structures and protective systems requires a firm understanding of the loadings imparted to structures by blast waves. While empirical methods can reliably predict these loadings in the far field, there is currently a lack of understanding on the pressures experienced in the very near field, where physics-based numerical modelling and semi-empirical fast-running engineering model predictions can vary by an order of magnitude. In this paper, we present the design of an experimental facility capable of providing definitive spatially and temporally resolved reflected pressure data in the extreme near field (Z<0.5 m/kg1/3). The Mechanisms and Characterisation of Explosions (MaCE) facility is a specific near-field evolution of the existing Characterisation of Blast Loading (CoBL) facility, which uses an array of Hopkinson pressure bars embedded in a stiff target plate. Maraging steel pressure bars and specially designed strain gauges are used to increase the measurement capacity from 600 MPa to 1800 MPa, and 33 pressure bars in a radial grid are used to improve the spatial resolution from 25 mm to 12.5 mm over the 100 mm radius measurement area. In addition, the pressure bar diameter is reduced from 10 mm to 4 mm, which greatly reduces stress wave dispersion, increasing the effective bandwidth. This enables the observation of high-frequency features in the pressure measurements, which is vital for validating the near-field transient effects predicted by numerical modelling and developing effective blast mitigation methods.

Numerical Simulation of an Electrothermal Ice Protection System in Anti-Icing and Deicing Mode

The design of efficient thermal ice protection systems is a challenging task as these systems operate in complex environments involving several coupled physical phenomena such as phase change, boundary-layer flow, and heat transfer. Moreover, certification rules are becoming more stringent, and there is a strong incentive for the reduction of fuel consumption. In this context, numerical tools provide a powerful asset during the design phase but also to gain insight into the physical mechanisms at play. This article presents modeling and simulation strategies for thermal ice protection systems. First, the model describing the behavior of the thermal protection system is presented. Second, a model and associated numerical method is presented for unsteady ice accretion. Third, the coupling methodology between the ice accretion solver and the heat conduction solver is described. In the fourth part, different methods to simulate the boundary-layer flow are described. Finally, some relevant examples are presented, both in steady and unsteady configurations.

Dynamical behaviors of aluminum droplets impinging on horizontal and inclined surfaces

Aluminum (Al) droplets collide with the wall of the combustion chamber in a solid rocket motor at different angles of incidence and velocities, which exhibit rebounding, splashing, and other behaviors. It increases the loss of two-phase flow to degrade the performance of the engine and poses a challenge to the thermal protection system. In this study, an experimental system in which molten Al droplets impact the walls of the chamber is designed. The size of the Al droplets produced by the generator ranged from 120 μm to 2000 μm while their speeds of impact ranged from 0.85 m/s to 9 m/s. This was used to examine the process of impact of Al droplets on flat and inclined walls. The residence time and spreading diameter of the droplets were quantified to reveal their mechanism of collision. Their empirical correlations were obtained by regressing the experimental data, and the predictive error of the model was within 20% of the experimental values. Furthermore, a theoretical model was developed to analyze energy distribution during the collision between the droplets and the wall. It showed that the effect of viscous dissipation energy on droplet flow was negligibly small, but the adhesion energy of the droplet increased significantly with its initial energy. In addition, the dimensionless sliding distance was S≈8 when the tangential Weber number was greater than 90, where this was related to the high surface tension of the Al droplets. The results here provide a theoretical basis for the design of thermal protection system of solid rocket motors.

Design and Implementation of Green Travel Smart Environmental Protection System

Design and Implementation of Green Travel Smart Environmental Protection System

Ballistic protection plates for military helicopters structures: Experimental and numerical research

The paper presents a combined experimental - numerical research that tries to evaluate the ballistic capabilities of three different types of protection plates having aluminum and/or steel skins and aluminum honeycomb core. Shootings with two types of bullets from a distance of 10 m were performed for each plate in an approved military training ground, which ensured the necessary safety and performance conditions. For each plate, the velocity before and after penetration was measured using an ultrafast camera, and a freeware code. The diameter of the hole made by the bullets was also measured. The experimental results were compared with the numerical ones obtained using the finite element method and a very good accuracy was noticed with differences less than 5%, validating thus the numerical models. The assessment of the degree of protection for each plate was made by evaluation of the energy absorbed by the plate from the kinetic energy of the bullet and by the reduction of the bullet velocity after penetration. The mass of each protection plate was also analyzed since it is a critical factor in the design of the ballistic protection systems. Conclusions were drawn regarding the efficiency of each of the three considered sandwich plates. The validation of the numerical models opens the path for the future assessment of other types of protection systems, made of lighter materials for the skins of the sandwich plates, namely fiber reinforced composites.

MODELING OF INFORMATION SECURITY SYSTEMS BASED ON MULTICRITERIA OPTIMIZATION ALGORITHMS

The system of ensuring the information security of an object is considered as a multicriteria task of choice. The possibility of applying multicriteria optimization methods to the design of an infocommunication facility protection system is analyzed. Formalized procedures for solving a multi-criteria selection problem are presented; algorithms for calculating and justifying the choice are shown.

Digitalising Social Protection Systems for Achieving the Sustainable Development Goals: Insights from Zimbabwe

Social protection systems, a target of the United Nation’s (UN) Sustainable Development Goals (SDGs), are intended to reduce extreme poverty, build human capital, and protect against risks to sustainable livelihoods and well-being. As social protection systems are by their nature inherently complex, multi-faceted, and socially embedded, it is inevitable that tensions will emerge between their design and implementation, representing design-reality gaps. These tensions present an excellent opportunity for cross-disciplinary research, by understanding how best to bridge these design-reality gaps. In this qualitative, interpretivist case study, we situate our work on the ground with the actors involved in the design, implementation, and use of a social protection system in Zimbabwe. We find interaction failures amongst some users; design-reality gaps around network access and ICT policy implementation; as well as mixed views regarding transparency and accountability of ICT. Our findings provide rich insights from ICT users in the global south and underscore the importance of the co-creation of IS interventions together with communities to ensure technologies consider social, political, economic, and network realities. We conclude by providing directions for future research.

Design of a smoke protection system for a closed car park

Today, this topic is relevant due to the fact that smoke and toxic combustion products that are released during fires are the main cause of death. According to statistics, about 42% of victims of smoke exposure get severe poisoning, eventually leading to death. At the same time, 70% of all those killed in a fire die precisely from the effects of smoke. The article discusses two types of smoke removal systems for closed car parks (traditional and impulse), analyzes the design features of these systems, performs calculations and evaluates the profitability of these systems in terms of energy consumption and economic costs.

基于增强型微处理器的燃气检测自保护系统设计与实现

基于增强型微处理器的燃气检测自保护系统设计与实现

Electrical Fire Safety Considerations in the Fire Protection System Design of High-rise Buildings

Electrical Fire Safety Considerations in the Fire Protection System Design of High-rise Buildings

Application of the principle of information objects description formalization for the design of information protection systems

The development of information independence of the State requires the introduction of the latest technologies for analyzing, storing, processing, and transmitting information. The focus of this work is improving information security systems with limited access, in particular the development of new methods of designing such systems, which are characterized by minimal influence of the subject-designer on the design process. The object of the study is the methodology and means of designing systems for restricting and controlling physical access, as well as access to information at objects of information activity and information and telecommunication systems of Ukraine. To exclude the influence of the subject of the designer, it is necessary to improve the design process itself. In this paper, the possibility of creating an automatic design system based on the representation of protection objects in the form of objects of a common structure has been mathematically proved. Such a structure combines both telecommunication objects and objects of information activity. Changes in the legislative, regulatory, and technical bases of information protection necessary for the implementation of the proposed system have been determined, in particular, granting the State Communications Committee of Ukraine new powers that ensure the balance of interests of the customer of protection systems and executors. The possibility of formalizing the representation of data on arbitrary objects of protection is shown. This representation makes it possible to create open library semantic databases with incomplete data on the object of protection. A theoretical base has been built that makes it possible to determine the correspondence between the set of threats to the information security of the object and the unambiguous corresponding list of countermeasures. At the same time, information protection projects are distinguished by evolution and uniformity of choice of a set of means of protection to any threats to objects of arbitrary complexity

Corrosion Simulations for Automotive Applications

Digitisation is making huge progress, and it is not stopping at automotive corrosion either. Within the entire automotive material life cycle, computer-aided approaches can already assist corrosion engineering and management today. From constructive corrosion protection on galvanically active hybrid constructions to the virtual design of active or passive corrosion protection systems, everything is possible. We are already very close to the goal of a continuous and realisable digital corrosion twin, but the complete integration into existing value chains is far from complete. This article provides an insight into current research and development and discusses the bottlenecks that still exist. The role of data or data collection and the smart combination of data- and physics-based modelling approaches are discussed. The possibilities and scope of applications of artificial intelligence methods for automotive corrosion topics are addressed. Concrete application scenarios are outlined by using examples, and the next work steps are derived.

Effective physical protection system design and implementation at a radiological facility: an integrated and risk management approach

Abstract Lives are threatened whenever there is an act of theft or destruction against a nuclear and radiological facility thus, physical protection systems are effectively employed to prevent or mitigate loss of valuable assets. Health facilities that provide radiotherapy services have in their facility a temporary storage unit where disused radioactive sources 60Co, 137Cs and 192Ir are kept and this raises concerns for effective physical protection. An integrated physical protection System was considered to consolidate of all sub systems, sensors and elements related to protection system for an effectively secured environment at a radiological facility. Sequence adversary diagram (ASD) was developed to depict the paths that enemies can take to achieve sabotage or stealing objectives and analyze flews in the paths. The approach to this security system effectiveness focuses on using probabilistic statistical methods for risk evaluation considering detection, delays and response. This paper considers the basic and effective elements required for physical protection system for a radiological center and makes risk evaluation as an approach of security system effectiveness which can serve as fundamental guiding principle for decision makers in the establishment of an effective physical protection for a radiological center.

Design and Evaluation of a Physical Protection System for a Radioactive Waste Intermediary Storage

The present work aimed to describe, present, and evaluate a Physical Protection System (PPS) for a hypothetical facility of an intermediate radioactive waste deposit, following international and national security criteria. Therefore, it carried out an evaluation of the Physical Protection System (PPS) applying the DEPO (Design and Evaluation Process Outline) methodology with a sequence of three phases of the protection system design and assessment of its vulnerabilities. The overall assessment of PPS was performed from the calculation of the overall probability of system effectiveness (PE) through the methods of adversary sequence diagrams, path analysis, and neutralization analysis. PPS presented a PE value of only 6.5%, three improvements were proposed and their impacts were analyzed. The reduction of the response time of the security forces led to a value of 78% of the PE and the increase of the time delay (TD) in the barriers closer to the target made the PPS efficiency reach 92%, higher than the acceptable value of 85%. The results showed that the evaluation of the proposed hypothetical project allowed adaptations so that the ideal level of PPS effectiveness could be reached with few interventions. The initial project was prepared in accordance with current regulations (traditional prescriptive approach) and, even so, presented a low probability of overall effectiveness, leading to the need for adjustments that were only possible by applying the DEPO methodology (performance-based approach).

Simulation research on thermal protection performance of firefighting robots and design of protection system

In response to manufacturing strategy demand, fire accidents in petroleum, chemical, forestry, and high-rise buildings are on the rise. Although the firefighting robot can replace fire rescue workers who come into the dangerous rescue site, electronic devices’ thermal failure problem caused by high temperatures in the whole electronic equipment problem is bigger. The proportion of electronic device thermal failure has a significant impact on the normal operation of electronic equipment. How to dissipate heat quickly and avoid local high temperatures becomes a key problem. Most domestic and foreign scholars only study the influence of thermal protection materials themselves on robot protection systems, and few study the influence of heat insulation materials and heat dissipation materials on robot protection systems through appropriate structure combinations. Therefore, the establishment of comprehensive high-temperature fire situations on the fire protection robot automatic detection of smoke concentration and temperature of heat insulation material and heat dissipation material composition of folded tensile structure and liquid nitrogen cooling system thermal protection model of robot thermal protection performance research is of great significance, at the same time through COMSOL Multiphysics software to simulate the proposed model, Select the best heat dissipation materials and heat insulation materials, protect the internal electronic components in the fire accident sustained high temperature, can adjust the temperature as soon as possible, make it adapt to the change of temperature field, for the rescue process to gain 2~15 minutes time duration.

Sacrificial Anode Cathodic Protection System Modelling Using Direct Boundary Element Method

Abstract Cathodic protection system is commonly employed approach for the protection of the metallic infrastructure placed in electrolyte against corrosion. Adequate design of the cathodic protection system requires the determination of electrical potential and current density distribution on the protected object surface that meets the defined criteria. In this paper, the application of the direct boundary element method in conjunction with Newton-Raphson method was considered for the calculation of the electric potential and current density distribution on the surface of the cathodically protected underground object. The considered method was applied on the sacrificial anode cathodic protection system of the underground pipeline. The non-linear boundary conditions of the electrode surfaces of the cathodic protection system are taken into account. The method was used to determine the current density and electric potential distribution on the external wall of the protected pipeline.

High-velocity impact study of an advanced ceramic using finite element model coupling with a machine learning approach

A numerical approach combining finite element modeling and machine learning is used to inform the material performance of an alumina ceramic tile undergoing high-velocity impact. In this study, the alumina ceramic tile is simulated by incorporating a user-defined Johnson–Holmquist–Beissel (JHB) material model within the framework of smoothed particle hydrodynamics (SPH) in LS-DYNA finite element software. The implementation of the JHB model is verified by comparing equivalent stress–pressure responses through a single element simulation test. After implementation, the computational framework is simulated across our chosen range of conditions by matching the results from both plate impact experiments and ballistic testing from the literature. The computational model is then used to generate training data sets for an artificial neural network (ANN) to predict the residual velocity and projectile erosion for an alumina ceramic tile undergoing high-velocity impact in the SPH framework. The ANN is then used to perform a sensitivity analysis involving exploring the effect of mechanical properties (e.g., strength and shear modulus) and impact simulation geometries (e.g., thickness of ceramic tile) on material performance (i.e., residual projectile velocity and erosion). Overall, this study shows the capability of the FEM-ANN approach in studying the high-velocity impact on ceramic tiles and is applicable to guide the structural-scale design of ceramic-based protection systems.

Legal Protection for Unregistered Clothing Design on Marketplace: Comparison Between the Indonesian and the UK Law

The industrial design protection system in Indonesia uses registration requirements, without registration, there is no protection. This is in contrast to the UK’s existing industrial design protection system, where the UK implements two protection systems, namely the registered design right or unregistered design right. This unregistered protection system is used in products that do not last long on the market such as fashion products and as an alternative for companies to test design prospects on the market. Unregistered protection systems are also used as design protection alternatives to prevent copying or plagiarizing of designs that do not yet have registration numbers. This article will discuss the following issues: 1) The legal protection of Korean pop idol clothing designs is reviewed based on Indonesian and English laws; and 2) The urgency of legal novelty in the industrial design law in Indonesia. In this study, the legal research method used is normative legal research with an approach through statutory regulations, a conceptual approach, and a comparative approach. The legal materials used are primary legal materials and secondary legal materials. The conclusion is that the industrial design protection system in Indonesia still has to go through the registration process, this is irrelevant to products or goods that cannot last long in the market because trends change easily. This is different from that in the UK where it implements an unregistered design right system where industrial design rights are obtained automatically.

The Effect of Social Benefit Reform on Educational Inequality

AbstractCross-country research argues that the design of welfare states and social protection systems shapes the intergenerational transmission of inequality. Studies that examine this relationship within a country are however lacking from the literature. Based on a quasi-experimental research design using difference-in-differences estimation and data from the Socio-Economic Panel, I analyse whether the educational disadvantage of children of long-term unemployment assistance recipients increased after changes to eligibility criteria, benefit levels, and conditionality were introduced in Germany in 2005. I find that differences in the probability to enter the academic secondary school track between children of parents receiving long-term unemployment assistance one year before the transition and children of parents not receiving unemployment or social benefits increased by 13 percentage points. In part, this was driven by the introduction of means-testing that changed the composition of unemployment assistance recipients. However, further decreases in the financial conditions of these already disadvantaged families following reductions in benefit levels appear as the main driver of the observed effect. Changes in parental subjective wellbeing due to increased benefit conditionality and stigma do not seem to play a significant mediating role. The findings highlight the important contribution of social policy to social mobility and equality of opportunity.