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Short term voltage stability poses a significant threat to system stability and reliability. This paper applies dynamic VAr injection to ensure short term voltage stability following a large disturbance in a power system with high concentration of induction motor loads. Decelerating and stalling of induction motor loads is considered to be the major cause of fault induced delayed voltage recovery (FIDVR) and short term voltage stability. If system dynamics are not taken into account properly, the proposed control solution may be an expensive over design or an under design that is not capable of eliminating FIDVR problems completely. In this work, the optimal amount and locations for installing dynamic reactive resources are found by control vector parameterization (CVP), a dynamic optimization approach. The efficiency and effectiveness of this approach is improved by utilizing results from trajectory sensitivity analysis, singular value decomposition and linear programming optimization. Dynamic optimization based on CVP approach is tested in an IEEE 162-bus system and a realistic large scale utility power system.

ObjectivesPerceptions of people regarding COVID-19 influences their health behaviour in terms of seeking public health services. This helps the government in planning appropriate public health strategies. Therefore, this study intends to explore the perceptions of people towards COVID-19 and their experiences during the pandemic in Nepal.Design, setting and participantsThis qualitative study was conducted among the public in Kathmandu, Kanchanpur, Bajura and Jhapa districts of Nepal. Eight focus group discussions and 40 in-depth interviews were conducted by using a maximum variation sampling method.ResultsThe findings were organised into the following themes: General understanding of COVID-19, Disease prevention, Source of information and misconceptions, Expectation and challenges; and Personal and societal consequences of COVID-19, social distancing and lockdown. There was a good general understanding among respondents about COVID-19, personal preventive measures and population-level strategies. They responded that the use of masks, sanitisers, handwashing and proper lockdown would help to prevent the disease. The respondents acknowledged the vital role of media in increasing awareness. Participants also expressed concerns over the misleading news spread by some media. The lack of social interaction, isolation and loss of income were raised as pertinent issues by the participants as potentially leading to psychological consequences. Health workers and public both raised concerns over inadequate Personal Protective Equipment, under-prepared health system, unorganised public quarantine centres, and public violation of lockdownConclusionsThis study reports participants’ views on disease prevention measures such as maintaining personal hygiene, adhering to physical distancing, and using personal protective equipments. Additionally, it illuminates the confusion among public due to conflicting public health messages from different sources of information which was deemed as misleading by the participants. This research sheds light on people’s perspectives and experiences that can inform population-targeted policies in the future.

Introduction Open defecation is ongoing in Nepal despite the rise in efforts for increasing latrine coverage and its use. Understanding the reasons for open defecation would complement the ongoing efforts to achieve the ‘open defecation free’ status in Nepal. This study aimed at exploring different motivations of people who practice open defecation in a village in Nepal. Methods This study was conducted among the people from the Hattimudha village in Morang district of eastern Nepal, who practiced open defecation. Maximum variation sampling method was used to recruit participants for 20 in-depth interviews and 2 focus group discussions. We adopted a content analysis approach to analyze the data. Results We categorized different reasons for open defecation as motivation by choice and motivation by compulsion. Open defecation by choice as is expressed as a medium for socializing, a habit and an enjoyable outdoor activity that complies with spiritual and religious norms. Open defecation by compulsion include reasons such as not having a latrine at home or having an alternative use for the latrine structures. Despite having a private latrine at home or access to a public latrine, people were compelled to practice open defecation due to constraints of norms restricting latrine use and hygiene issues in general. For women the issues with privacy and issues refraining women to use the same latrine as men compelled women to look for open defecation places. Conclusion Open defecation is either a voluntary choice or a compulsion. This choice is closely linked with personal preferences, cultural and traditional norms with special concerns for privacy for women and girls in different communities. The ongoing campaigns to promote latrine construction and its use needs to carefully consider these factors in order to reduce the open defecation practices and increase the use of sanitary latrines.

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This paper presents the results of a study for an on-line voltage security monitoring system in AEP. It is designed to work inside the control center with phasor measurement units (PMUS) providing the synchronized real-time measurements. Classification type decision tree (DT) models are utilized to predict voltage security status. Fast and direct measurement from PMUS combined with decision trees quickly assessesvoltage security, leaving more time for corrective or preventive actions. Two attributes are considered in the decision tree models: generator vars and angular difference. Both are observed to be good indicators of voltage security status. The paper focuses on the angle difference atb-ibutes because bus voltage angle is directly measured by the PMUS. A stressed power system is characterized by widerring angolar separation of bus voltage angles as it moves towards voltage insecurity.DTs exploit the complex non-li.new relationship between voltage security status and generator varsfangutar difference in terms hierarchical roles extracted tlom a large number of off-line loadflow simulations. Several DT models were analyzed using the existing PMUS, and in the future when additional PMUS are incrementally installed. A PMU placement technique is discussed to determine the critical locations of new PMUS. The voltage security monitoring system was tested on a 360-bus subsystem inside AEP.

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