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During a blackout, after the post-disaster collapse of an electric power system (EPS), units of thermal power plants should switch-over to the house load operation mode (PPW). However, regarding the dynamics of a post-disaster blackout process, many units can be in forced outage Therefore, restart of these units from the start-up sources with a self-start capability is necessary. The Transmission Network Code in force imposes periodic tests and system tests for such sources. Any system test must be preceded and followed by simulation investigations in which the possibilities: (1) to bring voltage to the started-up power plant by a starting path and (2) to activate the highest-power auxiliaries (PW) of the unit being started-up are evaluated. In the paper, chosen results of simulative investigations of the transient phenomena in the starting path from the hydroelectric power plant of Włocławek (HPP Włocławek) to the thermal power plant of P˛atnów (TPP P˛atnów), related to the system test conducted in September 2017 have been presented.

Many citizens of European countries may soon experience a long and extensive blackout. The lack of predictability in the output of renewable energy sources, aggravating the problem of consistently matching supply with demand on electric grids, along with cyber-attacks or even worse unpredictable incidents in the electric grid are some factors that may mean a blackout is much more likely than in previous years. This paper covers the possibility of an extensive blackout in a country of the interconnected European electricity transmission system or, even worse, a blackout in a wide area of the European continent. The topic of this paper becomes even more important and timely given the energy crisis due to the war in Ukraine, which has made the possibility of a blackout in the winter of 2022–2023 high. First, the major European blackouts that occurred in the past 20 years are presented, examining their causes. On 8 January 2021, the European electricity grid was divided into two separate sections, with different frequencies; some additional scenarios are considered which, if they had happened, could have led to blackouts in some European countries or, even worse, a wide area of Europe. This work also examines how to avoid such an eventuality, as well as how European TSOs should react in case a blackout occurs. Focused on the fast and reliable supply of consumers after a blackout, a novel restoration strategy based on the A* Algorithm is presented. Its efficiency is validated in the IEEE-39 and IEEE-68 bus systems.

Under-frequency load shedding (UFLS) appears to be an effective approach to preventing cascading outages that includes various methods. In recent years, much research has been done in the field of dynamic schemes. However, these schemes are less commonly used due to their disadvantages such as the inability to calculate the optimal shed load amount, the need to additional relays or communication infrastructures, etc. In contrast, static UFLS schemes are more common due to their simplicity, efficiency, fast implementation, as well as the unnecessity of additional equipment. However, how to determine the load shedding (LS) location and amount in static methods seems to be still challenging. Furthermore, conventional methods have a major drawback because of over shedding. In order to solve this problem, in this paper, a new static method is proposed to determine the location and amount of optimal LS based on co-simulation of DIgSILENT and MATLAB software. The system dynamics is simulated in DIgSILENT and optimization using imperialist competitive algorithm (ICA) runs in MATLAB. This co-simulation makes it possible to take advantage of both pieces of software. The results of the simulation on the IEEE 39-Bustest system in several scenarios clearly demonstrate the efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, a coupled interaction matrix is proposed to describe the interactions between line outages and the load shed at buses. The coupled interaction matrix is effectively estimated by the Expectation Maximization algorithm. A highly probabilistic coupled interaction model is further proposed to efficiently generate cascades with both line outages and the load shed based on the coupled interaction matrix and the distribution of initial outages. To mitigate cascading failures, critical links are identified based on the coupled interaction matrix by calculating a comprehensive severity index that considers the consequences of both line outages and the load shed. Simulation results on the IEEE 300-bus system verify the effectiveness of the proposed approach. The cascades generated from the coupled interaction model match the statistics of the original cascades very well. The identified critical links based on the comprehensive severity index enable a proper tradeoff between reducing line outages and reducing the load shed, leading to a better mitigation effect than only considering either line outages or the load shed. [ABSTRACT FROM AUTHOR]

In February 2021, rolling blackouts in Texas during Winter Storm Uri demonstrated the vulnerability of the State’s electric grid managed by the Electric Reliability Council of Texas (ERCOT). This article examines the technical causes of the ERCOT blackouts, financial and human consequences, and policy changes that could prevent recurrences. ERCOT planned for a winter load peak far below actual electricity demand. Further electricity shortfalls were caused by generation plants with varied energy sources becoming unavailable—natural-gas fired, coal-fired, nuclear, wind, and solar. Prior blackouts during a 2011 period of cold weather had shown the need for better resource planning and plant weatherization, but advance preparation was inadequate. The system of compensating generators in ERCOT was market-based with a $9,000 per megawatt hour cap on wholesale electricity rates—a so-called “Energy-Only market.” This regulatory system did not provide adequate incentives for generation plants to be operational during extreme weather, nor did it ensure that natural gas suppliers could deliver fuel to generators. Texas is well-situated for a return to the cost-of-service regulatory model; the State Legislature should consider this policy option.

Breath-hold diving (freediving) is an underwater sport that is associated with elevated hydrostatic pressure, which has a compressive effect on the lungs that can lead to the development of pulmonary edema. Pulmonary edema reduces oxygen uptake and thereby the recovery from the hypoxia developed during freediving, and increases the risk of hypoxic syncope. We aimed to examine the efficacy of SpO2, via pulse-oximetry, as a tool to detect pulmonary edema by comparing it to lung ultrasound B-line measurements after deep diving. SpO2 and B-lines were collected in 40 freedivers participating in an international deep freediving competition. SpO2 was measured within 17 ± 6 min and lung B-lines using ultrasound within 44 ± 15 min after surfacing. A specific symptoms questionnaire was used during SpO2 measurements. We found a negative correlation between B-line score and minimum SpO2 (rs = −0.491; p = 0.002) and mean SpO2 (rs = −0.335; p = 0.046). B-line scores were positively correlated with depth (rs = 0.408; p = 0.013), confirming that extra-vascular lung water is increased with deeper dives. Compared to dives that were asymptomatic, symptomatic dives had a 27% greater B-line score, and both a lower mean and minimum SpO2 (all p < 0.05). Indeed, a minimum SpO2 ≤ 95% after a deep dive has a positive predictive value of 29% and a negative predictive value of 100% regarding symptoms. We concluded that elevated B-line scores are associated with reduced SpO2 after dives, suggesting that SpO2 via pulse oximetry could be a useful screening tool to detect increased extra-vascular lung water. The practical application is not to diagnose pulmonary edema based on SpO2 – as pulse oximetry is inexact – rather, to utilize it as a tool to determine which divers require further evaluation before returning to deep freediving.

ObjectiveTo explore patients’ long-term experiences with drinking alcohol after Roux-n-Y gastric bypass (RYGB) for conceptualizing what may indicate problematic drinking behavior after bariatric surgery.Study DesignThree-center, observational study.Patients546 adult patients undergoing RYGB in the period 2003-2009 in Norway.Main Outcome MeasuresSelf-reported data on drinking behavior and experiences related to alcohol collected 10-15 years after surgery.ResultsOut of the 959 patients undergoing RYGB in the period, 29 were diseased and 546 participated in this follow-up study (58.7%). Focusing on suspicious changes in drinking behavior, 8.8% reported drinking more, 11.5% consumed alcohol at least twice a week, and 10.6% consumed at a minimum of 6 units of alcohol at a frequency of at least once monthly. The nature of hangovers had changed for about a third of the patients, with 21.6% reporting these to feel weaker or absent. Repeated alcoholic blackouts were reported by 11.9%. A subgroup of the patients were categorized as displaying presumed problematic drinking behavior(PPDB). Among the PPDB-men there was a significant association to having had a fall last year (6 (100.0%) PPDB-patients vs. 30 (29.7%) non-PPDB, p

Breath-hold diving (freediving) is an underwater sport that is associated with elevated hydrostatic pressure, which has a compressive effect on the lungs that can lead to the development of pulmonary edema. Pulmonary edema reduces oxygen uptake and thereby the recovery from the hypoxia developed during freediving, and increases the risk of hypoxic syncope. We aimed to examine the efficacy of SpO2, via pulse-oximetry, as a tool to detect pulmonary edema by comparing it to lung ultrasound B-line measurements after deep diving. SpO2 and B-lines were collected in 40 freedivers participating in an international deep freediving competition. SpO2 was measured within 17 ± 6 min and lung B-lines using ultrasound within 44 ± 15 min after surfacing. A specific symptoms questionnaire was used during SpO2 measurements. We found a negative correlation between B-line score and minimum SpO2 (r s = −0.491; p = 0.002) and mean SpO2 (r s = −0.335; p = 0.046). B-line scores were positively correlated with depth (r s = 0.408; p = 0.013), confirming that extra-vascular lung water is increased with deeper dives. Compared to dives that were asymptomatic, symptomatic dives had a 27% greater B-line score, and both a lower mean and minimum SpO2 (all p < 0.05). Indeed, a minimum SpO2 ≤ 95% after a deep dive has a positive predictive value of 29% and a negative predictive value of 100% regarding symptoms. We concluded that elevated B-line scores are associated with reduced SpO2 after dives, suggesting that SpO2 via pulse oximetry could be a useful screening tool to detect increased extra-vascular lung water. The practical application is not to diagnose pulmonary edema based on SpO2 – as pulse oximetry is inexact – rather, to utilize it as a tool to determine which divers require further evaluation before returning to deep freediving. [ABSTRACT FROM AUTHOR]

Today's modern society depends on a number of infrastructures to operate. Failures in these systems cause significant economic impacts and can also endanger the lives and health of the population. The high importance of these infrastructures has led them to increasing attention in recent years and are referred to as critical infrastructure. Critical infrastructure in the energy sector is considered to be one of the most important infrastructure networks significantly entering into ensuring the functional continuity of the society. Its importance is also perceived in terms of interconnections and correlations with other critical infrastructure sectors as well as in terms of electricity interconnectivity in Europe, as in the interconnected European system the effects are spreading across systems of all single country transmission system operators very quickly. For these reasons, the European Union considers this sector to be strategic and of European importance. The aim of the article is to clarify the primary causes of disruption of large-scale electricity supply and their impact on the functioning of society, focusing on the vulnerability of urbanized large settlements - urban agglomerations in the event of long-lasting blackout disturbances. It contains a presentation of the importance of electricity for society, definition and analysis of the causes of disruption of large-scale electricity supply continuity, consequences of large-scale blackout on community functioning and its basic functions and current knowledge on vulnerability of large urban agglomerations to long-term disruption of electricity supply and possible solutions. [ABSTRACT FROM AUTHOR]

Objective: To explore patients' long-term experiences with drinking alcohol after Roux-n-Y gastric bypass (RYGB) for conceptualizing what may indicate problematic drinking behavior after bariatric surgery. Study Design: Three-center, observational study. Patients: 546 adult patients undergoing RYGB in the period 2003-2009 in Norway. Main Outcome Measures: Self-reported data on drinking behavior and experiences related to alcohol collected 10-15 years after surgery. Results: Out of the 959 patients undergoing RYGB in the period, 29 were diseased and 546 participated in this follow-up study (58.7%). Focusing on suspicious changes in drinking behavior, 8.8% reported drinking more, 11.5% consumed alcohol at least twice a week, and 10.6% consumed at a minimum of 6 units of alcohol at a frequency of at least once monthly. The nature of hangovers had changed for about a third of the patients, with 21.6% reporting these to feel weaker or absent. Repeated alcoholic blackouts were reported by 11.9%. A subgroup of the patients were categorized as displaying presumed problematic drinking behavior(PPDB). Among the PPDB-men there was a significant association to having had a fall last year (6 (100.0%) PPDB-patients vs. 30 (29.7%) non-PPDB, p<.001). Among the PPDB-women, there was a significant association to having had alcohol problems prior to surgery (7 (70.0%) PPDB-patients vs. 67 (17.7%) non-PPDB, p<.001). Less significant associations to PPDB reported for explorative purposes were lack of patient education (men) (16 (26.2%) PPDB-patients vs. 8 (61.5%) non-PPDB, p=.014); more than 3 months persistent musculoskeletal pain (women) (45 (15.3%) PPDB-patients vs. 29 (24.6%) non-PPDB, p=.026); subjective problems with memory (women) (58 (20.7%) PPDB-patients vs. 10 (9.1%) non-PPDB, p=.006); and, receiving professional help for mental problems last 12 months (women) (29 (22.7%) PPDB-patients vs. 45 (14.7%) non-PPDB, p=.043). Conclusion: A subset of patients display drinking behaviors that may be consistent with postsurgical alcohol problems. Screening instruments like AUDIT may not be sufficiently specific to capture several risk behaviors occurring after bariatric surgery. [ABSTRACT FROM AUTHOR]

The aim of the research described in the article is to examine the options of addressing power supply disruption in the selected sectors of infrastructure due to emergency situation: snowfall in the area of Český Krumlov and Prachatice districts in the Czech Republic on April 28, 2017. Based on the characteristics of climatic, meteorological and geographic data, consequences of power supply disruption are described with emphasis on the approach of the electricity distributor and the affected infrastructure (transport and communication networks - mobile operators) in selected sectors. Reflection on the intervention activities of the Fire Rescue Service units in making roads passable has been carried out. The article evaluates preparedness and intervention activities based on the case study of emergency situation management procedures related to the selected infrastructure and suggests recommendations for their improvement. [ABSTRACT FROM AUTHOR]

Diesel–Electric Propulsion (DEP) has been widely used for the propulsion of various ship types including cruise ships. Considering the potential consequences of blackouts, especially on cruise ships, it is essential to design and operate the ships’ power plants for avoiding and preventing such events. This study aims at implementing a comprehensive safety analysis for a cruise ship Diesel– Electric Propulsion (DEP) plant focusing on blackout events. The Combinatorial Approach to Safety Analysis (CASA) method is used to develop Fault Trees considering the blackout as the top event, and subsequently estimate the blackout frequency as well as implement importance analysis. The derived results demonstrate that the overall blackout frequency is close to corresponding values reported in the pertinent literature as well as estimations based on available accident investigations. This study deduces that the blackout frequency depends on the number of operating Diesel Generator (DG) sets, the DG set’s loading profile, the amount of electrical load that can be tripped during overload conditions and the plant operation phase. In addition, failures of the engine auxiliary systems and the fast-electrical load reduction functions, as well as the power generation control components, are identified as important. This study demonstrates the applicability of the CASA method to complex marine systems and reveals the parameters influencing the investigated system blackout frequency, thus providing better insights for these systems’ safety analysis and enhancement. [ABSTRACT FROM AUTHOR]

• The generator startup process is modeled as the Markov Decision Process. • The Q-learning is applied in the planning of generator startup after blackout. • A new restoration strategy is proposed for the generator startup process. • The Upper Confidence Bound is used to optimize the selection of action of agent. With the expansion of the power system and the impact of natural disasters, blackouts are almost inevitable. A scientific restoration plan can effectively shorten the economic and social losses caused by blackouts. As the first step of power system restoration, the generator start-up process impacts the success rate and time consumption. Considering the diversity of constraints in the generator start-up process and the complexity of the topology, this paper proposes a planning method for the generator start-up process based on reinforcement learning. Q-learning is a model-free reinforcement learning algorithm that can cope well with complex environments and diverse constraints. First, the generator start-up problem is modeled as a Markov Decision Process, and the restoration operation and constraints are considered. Q-learning uses an artificial intelligence agent to plan the generator start-up process and guide operators. Second, different from the restoration methods of sequential restarting the generators, this paper presents a novel strategy for restoration by restoring the path of the subsequent generator while the current generator acquires cranking power. Then, the action selection mechanism is optimized by using the Upper Confidence Bound algorithm to address the shortcoming of low exploration effectiveness in the conventional Q-learning. Finally, the simulation results provide evidence of the excellent performance of the proposed method in terms of optimality and convergence. [ABSTRACT FROM AUTHOR]

• Blackouts bring major economic and societal repercussions. • Efficient black-start strategy is critical to address increasing risk of blackouts. • Variable speed hydro can provide a fast response and is used during black start. • Meet black start needs with renewables and cutting diesel use. • RES-BESS boosts power and fortifies an integrated renewable grid. A blackout refers to a total power outage that rapidly plunges the electrical power system into a severe crisis, posing significant challenges for subsequent restoration efforts. Blackouts can occur due to a range of factors, such as delays in clearing faults, generator malfunctions, equipment failures, and human errors. After a blackout occurs, all possible measures are taken to achieve the fastest power system restoration. To ensure preparedness for such emergencies, scheduled black start exercises are conducted using units capable of initiating power restoration from scratch, allowing authorities to assess their readiness in catastrophic scenarios. Numerous similar exercises have been conducted regularly generating to highlight the complexities of power system restoration of the grid with the black starts of hydro generating units. This has aided plant operators in improving restoration methods and finding additional remedial steps to enhance existing processes to achieve an effective black start exercise. This paper overviews the multiple mock black start exercises applied to hydroelectric generating units and discusses several blackouts worldwide. In addition, Tehri Hydro Power Plant is considered for the case study. Tehri HPP is linked to the 400 kV EHV grid, which was later upgraded to 765 kV transmission lines. Further, this paper observes and discusses various challenges encountered during mock black start exercises. Possible remedial actions are suggested to address these challenges. [Display omitted] [ABSTRACT FROM AUTHOR]

International humanitarian law is a branch of public international law that seeks to moderate the conduct of wars to protect those who are not taking part in the hostilities. Under international humanitarian law, belligerents may not intentionally target civilians or installations that are indispensable to the survival of the civilian population. While collateral harm to civilians and civilian infrastructure may occur, international humanitarian law prohibits attacks that may be expected to cause incidental loss of civilian life, injury to civilians, damage to civilian objects, or a combination thereof which would be excessive in relation to the concrete and direct military advantage anticipated. In practice, these principles have not always been honored or enforced. State and non-state actors have deliberately targeted civilians and/or disregarded civilian impacts, often for the purpose of pressuring political leaders to capitulate. The increasing occurrence and severity of harm to civilians and civilian infrastructure in modern conflicts calls into question the continuing relevance of what were once viewed as fundamental protections. In this paper, we present a case study involving Russia's 2022–23 attacks on Ukraine's electric power infrastructure, which left millions of civilians without heat, water, or other basic services for extended periods in harsh winter conditions. Considering the scope, scale, and long-term impacts of these attacks, we conclude that Russia violated international law. We also suggest that a new international protocol may be necessary in order to more effectively deter and punish attacks on civilian infrastructure in future armed conflicts and military occupations. • "What the Ukrainian energy system has been experiencing since October 2022, no energy system in the world has ever experienced." • "Russia came frighteningly close to taking down the entire power grid in Europe's second-largest nation." • "Russia's effort to disrupt power delivery systems throughout Ukraine violated international laws" • "We propose the adoption of a new international code of conduct to better protect civilian access to electric power." [ABSTRACT FROM AUTHOR]

This paper presents two schemes of UFLS to keep the system frequency within safe limits. GA-based scheme is introduced as an offline method to get the proper amount of shed load achieving the minimum and steady state frequency within permissible limits. Due to the probability of generation variation and generating units outage during shedding process, ANN-based scheme is presented as an online method to adjust the proper amount of load shedding at any amount of power deficit. Multi scenarios of contingences are carried out on offline mode using GA optimization technique to collect the training patterns for ANN. The ANN-based scheme can consider the generation variations during the load shedding process. Although using this scheme may shed more loads, it maintains the frequency to be within permissible limits at various disturbance scenarios particularly at the absence of secondary control. An analytic system frequency response (SFR) model with no secondary control incorporating UFLS scheme is presented. The proposed method is compared with the classical adaptive method to prove its effectiveness. Results are presented in the form of time domain simulations via MATLAB/SIMULINK.

Northern electric grid of Italy was involved in a black start mock drill. This test took place on November 2016 in order to check the coordination and efficiency of all the operational staffs and the automatic regulators involved in the case of a real blackout scenario. This paper presents the results of a research carried out in collaboration with Terna Rete Italia (the Italian Transmission System Operator), in order to find strengths and weaknesses and eventually to upgrade the existing restoration plan. Starting from the measures coming from generating plants and substations bars, the model of frequency regulation system for both the participating hydro and thermal power plants is developed. This work gives the system operator an essential tool to understand many complex dynamics and phenomena occurred during the test. At the same time, a robust model simulating the system behavior with different grid configurations is presented: it gives the opportunity to enhance both the classical power system control theory and the black start practices.

The article is focused on the issue of blackouts in a water industry and the selection of a renewable energy source for a water treatment plant. In the case of power outage, it is necessary to constantly ensure the supply of a drinking water, if this requirement would not be met, it could cause of deterioration of hygiene and health of the population. To be able to convey drinking water during a blackout, it is mandatory to have a backup power supply. The state of the current water treatment plants in the Czech Republic is that they are using diesel generators as backup power supply, which causes air pollution. There are other options of power supply that can be used, such as renewable energy sources. By using a multi-criteria analysis method, renewable energy sources were analyzed for a water treatment plant in the selected region. Based on the results, it seems that the most suitable choice is a small hydro power plant at the entry points of water treatment plant. Other possibilities of renewable energy sources that may be suitable for a water treatment plant and the usage of a multi-criteria analysis method for a water treatment plant in other countries are also discussed.

The article concerns the energy security of a wastewater treatment process caused by unforeseen situations related to the risk of electrical power outages. In this case, renewable energy sources based on distributed generation power systems can solve this problem in each wastewater treatment plant. The article highlights e related challenges and proposes the direction of solutions in this regard based on Czech conditions. The first part of the paper deals with the consequences of long-term outage of wastewater treatment plants on the population and the environment. There are several solutions presented for blackout conditions, and model calculations are made based on data from a Czech wastewater treatment plant. Diesel engine-generators, biogas as a cogeneration source of heat and electricity, solar panels with storage systems and combined biogas and solar systems were considered as approaches to provide energy autonomy during a blackout in a wastewater treatment plant. Special attention was paid to a combination of CHP units with solar panels and batteries. The results were evaluated for three different locations for this combination. It was concluded that biogas combustion in the CHP unit was the most profitable option, allowing the production of electricity independently of the grid for its own consumption and possibly for other operations. The last part of the paper deals with the transition to island operation, which must occur during a blackout. This transition is more difficult for both solar panels and cogeneration units if they were to supply electricity to the grid before a blackout. The transition to energy island operation could be ensured by frequency relay and processor devices to control the circuit breaker. Then, to maintain island operation, it would be necessary to have an automatic load shedding/application system.

In recent years, the occurrence of cascading failures and blackouts arising from cyber intrusions in the underlying configuration of power systems has increasingly highlighted the need for effective power management that is able to handle this issue properly. Moreover, the growing use of renewable energy resources demonstrates their irrefutable comparative usefulness in various areas of the grid, especially during cascading failures. This paper aims to first identify and eventually protect the vulnerable areas of these systems by developing a hybrid structure-based microgrid against malicious cyber-attacks. First, a well-set model of system vulnerability indices is presented to indicate the generation unit to which the lines or buses are directly related. Indeed, we want to understand what percentage of the grid equipment, such as the lines, buses, and generators, are vulnerable to the outage of lines or generators arising from cyber-attacks. This can help us make timely decisions to deal with the reduction of the vulnerability indices in the best way possible. The fact is that employing sundry renewable resources in efficient areas of the grid can remarkably improve system vulnerability mitigation effectiveness. In this regard, this paper proposes an outstanding hybrid-energy framework of AC/DC microgrids made up of photovoltaic units, wind turbine units, tidal turbine units, and hydrogen-based fuel cell resources, all of which are in grid-connect mode via the main grid, with the aim to reduce the percentage of the system that is vulnerable. To clearly demonstrate the proposed solution’s effectiveness and ease of use in the framework, a cyber-attack of the false data injection (FDI) type is modeled and developed on the studied system to corrupt information (for instance, via settings on protective devices), leading to cascading failures or large-scale blackouts. Another key factor that can have a profound impact on the unerring vulnerability analysis concerns the uncertainty parameters that are modeled by the unscented transform (UT) in this study. From the results, it can be inferred that vulnerability percentage mitigation can be achieved by the proposed hybrid energy framework based on its effectiveness in the system against the modeled cyber-attacks.

Twitter provides a real-time venue for monitoring alcohol consumption and negative alcohol-related consequences. "Blackouts," defined as events involving alcohol-induced amnesia, are commonly endorsed among social drinkers. However, the term "blackout" has been used in popular culture to describe being intoxicated. We qualitatively examined the content of alcohol-related blackouts posts ("Tweets") on Twitter, focusing on reflections post-drinking that involved clear references to memory loss. We examined publically available Tweets that referenced blackouts after an alcohol consumption event (n = 3,574). Twitter represents a relatively unfiltered glimpse at reflections on alcohol-induced amnesia. As hypothesized, most tweets referencing blackouts did not clearly describe amnesia. In the Tweets that clearly reference amnesia, we identified several themes. Tweeters referenced an 'AlterEgo' who was responsible for all the intoxicated behaviors that were inconsistent with the Tweeter's personality. Additionally, the Tweets discussed ways in which the drinker recovered memories (e.g. from friends, from social media), other events that occurred during the amnesia (e.g. loss of items, help from friends, sexual experiences), and regret about having lost memories. Some Tweeters requested assistance from their followers to reconstruct their drinking event. Tweets have the potential to set norms about acceptable behaviors or scripts following a blackout. Since most blackout Tweets are ambiguous with regards to alcohol-induced amnesia, these Tweets might be leading people to believe that blackouts are passing out or just periods of heavy intoxication. In addition, themes from these Tweets can inform future interventions by using the cognitions surrounding this high-risk behavior. [ABSTRACT FROM AUTHOR]

Background: The role of alcohol sensitivity in the experience of blacking out and passing out has not been well established. Here, we examined the relation between individual differences in alcohol sensitivity (i.e., numbers of drinks required to experience various effects of alcohol) and reports of blacking out and passing out in the past year. Methods: Participants (925 healthy, underage college student drinkers) completed the Alcohol Sensitivity Questionnaire (ASQ) and reported on their past year blacking out and passing out experiences. Results: The fit of the ASQ's 2‐factor structure was fair (CFI = 0.90, RMSEA = 0.09) in this sample of underage drinkers. In unadjusted models, higher ASQ scores (i.e., requiring more drinks to experience effects, indicating lower alcohol sensitivity) were associated with experiencing more blackouts (IRR = 1.68 [1.31–2.15]) and passing out (IRR = 2.25 [1.59–3.18]) in the past year. After controlling for typical consumption, however, higher ASQ scores were associated with fewer past‐year blackouts (IRR = 0.76 [0.60–0.98]). Total ASQ scores moderated the relationship between typical alcohol consumption and blackout occurrence (interaction IRR = 0.96 [0.93–0.98]), but not passing out occurrence (interaction IRR = 0.95 [0.89–1.01]), with the quantity of alcohol consumed more strongly associated with blackout occurrence among higher‐sensitivity than lower‐sensitivity drinkers. Conclusions: These findings are consistent with prior work suggesting that low sensitivity may act as a paradoxical risk factor for certain heavy drinking effects, contributing to higher levels of alcohol consumption and more frequent negative consequences while also conferring protection (relative to high‐sensitivity peers) at a given level of alcohol exposure. [ABSTRACT FROM AUTHOR]

The existence of bullying is certain at the level of country or popolations who have old traditions and a large percentage of the communities who chooses living in rural areas, on principles related to the traditional way of life. This traditional style also involves autonomy in terms of infrastructure: the toilet outside the house, in the yard, the households having their own source of water, septic tanks instead of sewerage and even transport with animals and traditional wooden vehicles. The purpose of our study is to measure the perception of those people regarding the reflection of their image in mass-media and social media. The toilet in the yard (outdoor) had become subject for bullying and public shaming, not only as an indicator for economy. The research uses both empirical and theoretical methods, qualitative and quantitative: Analysis of statistical data and case studies, as well as the Sociological Survey. The main hypothesis from which the research have started in this research is that people who still have a toilet outdoor perceive this as a necesity for autonomy and they also perceive the news about this subject in mass -media and social media as bullyng and public shaming. [ABSTRACT FROM AUTHOR]

After road accidents, the person responsible for the accident often declares a "blackout" at the wheel. Although this claim is often used as a protective claim, there are also numerous diseases that can indeed lead to a transient loss of consciousness at the wheel. In these cases the correct medical examination by the clinician as well as the initiating of specific examinations in the run-up to the medical traffic examination can support the subsequent assessment of the driving ability or driving suitability by the traffic physician. This article is intendedas a guide to these proceedings. [ABSTRACT FROM AUTHOR]

In this paper, real outage data from utilities are analyzed to gain better understanding of cascading outage propagation. In order to accurately estimate the interactions between component outages, two mechanisms are introduced: the evolution of interactions over generations and the memory between consecutive generations. A metric, the expected number of outages following one component outage, is calculated based on the estimated interaction networks by solving a set of carefully formulated linear equations, considering loops due to the complex component interactions. Existence of unique positive solution for the linear equations is mathematically proved. Components that are critical for outage propagation are further identified based on the developed metric. Besides, the outage propagation properties are revealed by the interaction networks estimated from real outage data. Further, the cascades simulated from a highly probabilistic generation-dependent interaction model using the estimated interactions well capture the properties of the original outage data in terms of the distribution of the number of line outages, the offspring mean of the branching process, the distribution of the component metrics, and the identified critical components. Cascading failure risks are greatly mitigated by reducing the probability that the identified critical components fail. [ABSTRACT FROM AUTHOR]

Introduction and Aims: COVID‐19, considered a pandemic by the World Health Organization, overwhelmed hospitals in the USA. In parallel to the growing pandemic, alcohol sales grew in the USA, with people stockpiling alcohol. Alcohol‐induced blackouts are one particularly concerning consequence of heavy drinking, and the extent to which blackout prevalence may change in the context of a pandemic is unknown. The purpose of the current study is to describe the prevalence of publicly available tweets in the USA referencing alcohol‐induced blackouts prior to and during the COVID‐19 outbreak. Design and Methods: We used Crimson Hexagon's ForSight tool to access all original English tweets written in the USA that referenced alcohol‐related blackouts in 2019 and 2020. Using infoveillance methods, we tracked changes in the number and proportion of tweets about blackouts. Results: More alcohol‐related blackout tweets were written between 13 March and 24 April in 2020 than 2019. In addition, a greater proportion of all tweets referenced blackouts in 2020 than in 2019. In the period prior to the 'stay at home' orders (January to mid‐March), the proportion of blackout tweets were higher in 2020 than 2019. Discussion and Conclusion: Our findings demonstrate that references to high‐risk drinking persist during the pandemic despite restrictions on large social gatherings. Given that the internet is a common source of information for COVID‐19, the frequent posting about blackouts during this period might normalise the behaviour. This is concerning because alcohol use increases susceptibility to COVID‐19, and alcohol‐related mortality can further tax hospital resources. [ABSTRACT FROM AUTHOR]

After large-scale photovoltaic (PV) and wind power integration with the national grid, the island grid detection is a crucial technique that identifies when a grid should be considered as dead. This logic is built in an IEC61850 grid controller which mainly depends on the bus bar scheme and fault type. It becomes more complex when the ½ circuit breaker scheme is utilized. The lack of communication redundancy causes island mal-operation due to the substation's DC supply failure. In order to avoid such mal-operation discrepancies, this paper investigates the conventional islanding detection method. Then, an advanced IEC61850 grid controller 2oo3 architecture is proposed for islanding detection, based on SAS redundant communication which improves reliability. However, even if there is an interface communication failure, the power plant control center can still detect the islanding through the proposed IEC61850 grid controller and SCADA IEC60870-5-101/104 gateways integration. This method has the tendency of full supervision of the entire grid and perfect logical judgment by plant operation staff. This feasible and the proposed redundant communication architecture can play a decisive role for power system network stability in order to avoid system blackout. [ABSTRACT FROM AUTHOR]

Summary: Microgrids are considered a reliable option for its ability to work autonomously during the event of faults. With widespread blackout, microgrid itself may experience blackout and hence, fails to support the customers. For system operators, the selection of an appropriate black start unit and procedure is of utmost importance. A fast and reliable black start unit will reduce vulnerability in grid operation. This paper proposes a novel black start methodology for a microgrid where the appropriate Distributed Energy Resource (DER) is utilized as black start unit for the recovery at the planning phase. In order to validate the findings, the proposed methodology is implemented on an industrial microgrid. Results show that bottom‐up restoration with solar photovoltaic systems having Battery Energy Storage System (BESS) can offer fast and faithful restoration in comparison to other DER units. [ABSTRACT FROM AUTHOR]

Terahertz communication is considered as a potential solution to alleviate the communication blackout. However, it is not clear how the shape parameters of the vehicle affect the propagation of terahertz communications in the plasma sheath. In this article, the influence of half-angle on the plasma flow and terahertz propagation characteristics around blunt cone vehicle was investigated using the numerical hypersonic hydrodynamic model and multilayer transmission model. The maximum electron number density in the plasma sheath near the antenna decreases with the decreasing half-angle. The thickness of the high-density section in the plasma sheath is almost unaffected by the half-angle. As a result, the terahertz wave attenuation decreases with the decreasing half-angle. The half-angle is reduced from 20° to 5°, and the attenuation of electromagnetic waves is reduced by about 25 dB. Therefore, reducing the half-angle of blunt cone vehicle can effectively reduce the attenuation of electromagnetic waves. Finally, the feasibility of lowering the half-angle to solve the blackout problem during the whole reentry process was discussed; the results show the operating frequency of terahertz wave that maintains normal communication when the half-angle is 1° is reduced by 0.1 THz compared with the half-angle of 9°. Based on the study, a new scheme combining the reduction of half-angle of blunt cone vehicle and terahertz communication was proposed in this article to mitigate the RF blackout. [ABSTRACT FROM AUTHOR]

A blackout on the island of Hokkaido occurred following a massive earthquake on September 6, 2018. This study analyzed the sleep pattern data of junior high school students on the night of the blackout in comparison to a normal night. Data were collected from 52 junior high school students from a school away from the earthquake's epicenter but within the blackout area. Although the students normally slept less than 8 h per night, they slept for nine and a half hours during the blackout night. The duration during the blackout corresponded to the ideal sleep duration recommended by the NSF and AASM. [ABSTRACT FROM AUTHOR]

Background: Alcohol-induced blackouts are a common high-risk outcome of heavy episodic drinking and are considered a marker of problematic alcohol consumption. One's estimates of the prevalence and peer approval of heavy episodic drinking (i.e., social norm perception, descriptive and injunctive norms, respectively) strongly relate to high-risk alcohol consumption. However, it is unknown whether the intention to blackout and the occurrence of alcohol-induced blackouts also associates with these estimates. Therefore, the purpose of this paper is to explore the relation between participants' social norm perception and alcohol-induced blackout intentions and recent blackout history.Method: A total of 4430 participants completed an online survey with an average age of 19.97 (SD = 1.70) years. A series of ANOVAs and a structural equation model examined the relation between social norm perception, intention to blackout, and recent blackout history.Results: In the structural equation model, the social norm variables (descriptive and injunctive norms) were associated with higher levels of blackout intentions and recent blackout history. The global fit indices suggest that the data fit the model, χ2 (n = 4248, 442) = 7755.90, p < .001, CFI = .96, TLI = .96, RMSEA = .06 (CI90 .061-.064).Conclusions: Participants with a higher likelihood of having a past 30-day history of alcohol-induced blackouts and higher blackout intentions believed that many of their peer groups approved of certain alcohol-related behaviors and that their peer groups drink frequently and drink higher quantities. Future interventions may assess the impact of adjusting social norms on both the intention to blackout and experiencing blackouts. [ABSTRACT FROM AUTHOR]

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The modern and luxurious life styles with the increased automated machinery and devices have increased the demand for electrical energy. This has been one of the primary reasons to maintain prescribed standards in the field of electrical energy in terms of reliability, power quality, and stability of power system network. When such highly interconnected power system network experiences a disturbance like unbalances in load, frequencies, unnecessary tripping, or due to some external causes, it leads to unsynchronization with power grid effecting a massive damage to economy of the country. So it is important and necessary to have high secured power system. Even though Indian power system is well equipped, well designed with protection system, a massive power outage has been taken place in Mumbai in October 2020 leaving many areas affected. This paper describes a detailed study on Mumbai power outage 2020. [ABSTRACT FROM AUTHOR]

Summary: The topological analysis of complex networks provides essential information about its structure and vulnerability. However, there are many ways to represent a network as a graph. The electric power grid can be analyzed as a simple graph by ignoring its electrical dynamics and considering it as unweighted and undirected. These methods do not include the weight of lines, which is a disadvantage of such an analysis. For a power grid network, weights (impedance) relate to electrical concepts, such as maximum power through the line. So a weighted network assessment can improve the power grid network representation. This article did the structural analysis of the Indian power grid and IEEE 300, 118, 39 bus network based on both topological and electrical connectivity. The topological analysis was carried out by taking into account these networks as unweighted and weighted. Our work divided into three categories. Firstly, we have analyzed these power grid networks structural details. Secondly, through the matrices adapted from complex network theory, we identified the most critical transmission lines and buses. We estimate the impact on the performance of the electrical power grid by modeling cascade events from the removal of these lines and substation. Based on this removal strategies, AC optimal power flow problem was solved. Finally, the results are compared for both weighted and unweighted networks. In conclusion, weighted network analysis provides a better algorithm for vulnerability assessment than an unweighted network. [ABSTRACT FROM AUTHOR]