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Power outages which may be triggered, for example, by natural hazards and system failures are a common phenomenon, associated with large impacts on society including the healthcare sector. Minimising adverse impacts effectively requires an analysis of possible impacts and the identification of measures aiming at reducing vulnerability and increasing resilience.

To systematically identify impacts as well as preparation, mitigation and recovery (PMR) measures, a moderated workshop with participants representing different healthcare sub‐sectors in Germany was conducted and complemented by semi‐structured interviews and a thorough analysis of literature. Impacts were determined for three scenarios of power outage duration, <8, 8‐24 and >24 hours.

Whereas hospitals are in general well prepared with respect to shorter outages, due to obligatory emergency power in Germany, outpatient medical care, nursing homes (NH) and, in particular, home‐care nursing are early affected. Failure of these sub‐sectors puts additional strains on hospitals. If outages last more than one day and are associated with failure of other critical infrastructures (CIs), especially water supply, hospitals may be severely affected. Effective preparation and mitigation measures identified based on a facility‐specific impact analysis, as well as good cooperation between actors, may reduce impacts.

The largely case‐study‐based literature is complemented by a systematic and extensive analysis of direct and indirect impacts on the main healthcare sub‐sectors in Germany, followed by an identification of specific PMR measures. As a novelty outage duration is explicitly accounted for. Also, interdependencies between the healthcare sub‐sectors as well as dependencies on other CI are considered.

Drawing from transactional stress and conservation of resource theories, this study untangles the relationship between power outage, patient incivility, job stress and proactive service performance. Further, this study also explores the mediating role of patient incivility and job stress.

A questionnaire-based survey was used, and data were collected from 275 healthcare professionals working in various public hospitals in Pakistan through convenience sampling. Structural equation modeling (SEM) via Smart PLS was used for data analysis.

Results revealed that power outage has significant positive impact on patient incivility and patient incivility has significant direct effect on job stress. Job stress has significant negative relationship with proactive service performance. Findings also confirmed that patient incivility mediates the relationship between power outage and job stress, and job stress mediates the relationship between patient incivility and proactive service performance.

This study helps the health administrators to think about the service standards of the public hospitals. Implications of this study are not limited to health sector. This study is useful for other service sectors where performance of employee affected by power outage. In addition to this, the current research helps to conduct research in other developing and underdeveloped countries which also face the problem of power outage.

This study marks the first step toward establishing power outage as an organizational behavior construct by demonstrating that power outage impacts significantly on proactive service performance. This study also explored the relationship between job stress and proactive service performance which was also not explored before.

The purpose of this paper is to pursue two following main goals: first, theorizing a new concept named as equivalent bus load in order to make a promising simplification over power system analysis. Second, proposing an outstanding fast and simple approach based on introduced concept for voltage estimation after multiple component outages while satisfying required accuracy.

Equivalent load bus theory introduces three transfer matrices that describe power system topology. Mentioned matrices could be calculated simply after system reconfiguration without matrix inversion. Using transfer matrices a large-scale power system can be modeled by a simple two-bus power system from the viewpoint of any desired bus so that load flow calculation leads to same value. The analysis of simplified power system yields to extract a new incremental model based on equivalent bus load theory that will be distinguished as an outstanding fast method for voltage estimation aim.

A deep study for fast voltage estimation aim is dedicated to evaluate proposed method from the accuracy and quickness point of view and the outcomes are compared to a well-known method as Distribution Factors (DF). Results and computational times unveil that presented approach is more accurate and much faster.

A novel and new fast voltage estimation method for assessment of power system component outages is introduced.

An unreliable supply of grid electricity has a strong negative impact on industrial and commercial profitability as well as on household activities and government services that rely on electricity supply. This unreliable grid electricity could be a result of technical and security factors affecting the grid network. Therefore, this study aims to investigate the effects of technical and security factors on the transmission and distribution of grid electricity in Uganda.

This study used the ordinary least squares (OLS) and autoregressive distributed lag (ARDL) models to examine the effects of technical and security factors on grid electricity reliability in Uganda. The study draws upon secondary time series monthly data sourced from the Uganda Electricity Transmission Company Limited (UETCL) government utility, which transmits electricity to both distributors and grid users. Additionally, data from Umeme Limited, the largest power distribution utility in Uganda, were incorporated into the analysis.

The findings revealed that technical faults, failed grid equipment, system overload and theft and vandalism affected grid electricity reliability in the transmission and distribution subsystems of the Ugandan power grid network. The effect was computed both in terms of frequency and duration of power outages. For instance, the number of power outages was 116 and 2,307 for transmission and distribution subsystems, respectively. In terms of duration, the power outages reported on average were 1,248 h and 5,826 h, respectively, for transmission and distribution subsystems.

This paper investigates the effects of technical and security factors on the transmission and distribution grid electricity reliability, specifically focusing on frequency and duration of power outages, in the Ugandan context. It combines both OLS and ARDL models for analysis and adopts the systems reliability theory in the area of grid electricity reliability research.

An electrical company is responsible for the maintenance of a transmission network of high voltage electricity. The maintenance schedule must be planned so as to minimize outage costs, taking into consideration various factors such as system security/reliability, system availability, and manpower utilization. With the rapid growth of organization, planning engineers are required to fulfill additional roles in order to increase productivity. To this end, a fast response and accurate mechanism is required to assist the planning engineers in dealing with the daily operation. This paper describes how a proposed maintenance schedule can be obtained automatically by the adoption of genetic algorithm. The main aim is to determine the maintenance schedule of circuit outage with minimizing the maintenance cost and maximizing the circuit availability under certain unavoidable system constraints. Further, an additional search mechanism called “final tuning search” is developed to enhance the system performance.

Infrastructure deficiency and supply disruption challenges are quite common among developing economies. While Sub-Saharan Africa is not unique to these challenges, it is the extent of levels of infrastructure deficiency and disruptions that affect the level of performance of small businesses. Literature on the performance of small businesses suggests both infrastructure availability and disruptions affect the performance of small businesses, but the effects on informal enterprises that operate from locations where the supply of infrastructure is weak are less documented. The paper, therefore, investigates the effects of four types of infrastructure supply in two dimensions of availability and disruption levels on the performance of informal enterprises in 12 Sub-Saharan African countries.

The study uses data from World Bank informal enterprises surveys based on a sample of 3 735 informal enterprises. The study uses the multiple analysis of variance method based on the World Bank's Informal Enterprise Surveys (IFS) country-level cross-sectional data collected between 2009 and 2019.

Results show infrastructure supply is quite low irrespective of the form of infrastructure. Infrastructure availability is associated with high supply disruptions. Infrastructure supply deficiency and disruption intensities are negatively associated with informal enterprises' performance. Finally, the effects of both infrastructure availability and supply disruptions are positively associated with informal enterprises' business activity levels.

Due to data limitations, only four types of infrastructure are captured in the analysis. A wider variety of types of infrastructure could improve the analysis.

Given the deficiency level of infrastructure and its implications on informal enterprise development, therefore, policy interventions aiming at addressing informal enterprises' challenges should focus on improving infrastructure supply deficiencies and disruption challenges. This paper provides the link between infrastructure levels, infrastructure supply disruptions and performance of the informal enterprises which is an essential starting point for policy intervention in informal enterprise development.

This paper aims to survey the need for full capacity utilisation of transmission lines in power systems network operations. It proposes a review of the N-1 security criterion that does not ensure reliable dispatch of optimum power flow during outage contingency. The survey aims to enlarge the network capacity utilisation to rely on the entire transmission lines network operation.

The paper suggests transmission line switching (TLS) approach as a viable corrective mechanism for power dispatch. The TLS process is incorporated into a constraint programming language extension optimisation solver that selects the switchable line candidates as integer variables in the mixed integer programming problem.

The paper provides a practical awareness of reserve capacity in the lines that provide network security in outage contingency. At optimum power flow dispatch, the TLS is extended to optimal transmission line switching (OTLS) that indicates optimal capacity utilisation (OCU) of the available reserve capacity (ARC) in the network lines.

Computational efficiency influenced the extension of the OTLS to optimal transmission switching of power flow (OTSPF). The application of OTSPF helps reduce the use of flexible AC transmission systems (FACTS) and construction of new transmission lines..

The paper surveys TLS efforts in network capacity utilisation. The suggested ARC fulfils the need for an index with which the dispatchable lines may be identified for the optimal capacity utilisation of transmission lines network.

The purpose of this paper is to study the failures spread in complex power grids, and what topology of power grids is best for preventing or reducing blackouts.

Based on the study of cascading failure models of complex power networks, an extended dynamical cascading failure model is proposed. Based on this model, two representatives of the complex power grids, the small‐world network and the scale‐free network, were simulated for line cascading failure. The power loss caused by cascading failures and the spreading speed of cascading failure are discussed.

Power loss caused by cascading failures in the small‐world network is much larger than that in the scale‐free network, and the speed of cascading failure propagation in the small‐world network is much faster than that in the scale‐free network.

The establishment of the dynamical cascading failure model considering other protection devices needs further study.

The results of this study can be beneficial in system planning and upgrading.

An extended dynamical cascading failure model is proposed and cascading failures in different topology of power grid are discussed.

After a massive storm hit the northern Illinois service area of electric utility Commonwealth Edison on July 11, 2011, more than 900,000 customers were left without power during a hot, humid summer. ComEd crews and reinforcements from more than a dozen other states worked for days afterward to restore service. Meanwhile, the company's months-old social media strategy faced its first major test. The eChannels social media team, part of ComEd's customer operations division, worked around the clock to respond to posts from customers on social networking sites Facebook and Twitter. At a time when the company faced public debate and criticism over its plan to raise electricity rates, in part to invest in smart-grid upgrades, engaging directly through social media was a way to strengthen relationships with customers and the general public, consistent with an important corporate goal: “Keep the lights on and information flowing.”

After discussing the case, students will:

• Develop an appreciation for the role social media can play in shaping a company's reputation

• Understand how companies can use social media to engage customers directly in order to protect their reputations

• Understand the role these interactions with customers can play during a crisis situation

• Recognize the added reputational risk when a company's core business is directly impacted by a natural disaster

Develop an appreciation for the role social media can play in shaping a company's reputation

Understand how companies can use social media to engage customers directly in order to protect their reputations

Understand the role these interactions with customers can play during a crisis situation

Recognize the added reputational risk when a company's core business is directly impacted by a natural disaster

In operating any computer system, whether a small personal computer or a large main‐frame system, power protection should be considered with respect to protecting computer data and possibly the hardware. But how much protection is needed? This article addresses basic issues computer users should consider before selecting power protection. Although some of the information applies chiefly to mainframe computers, the basic concepts (backing up data and line filters) apply to all systems.