Optimal Topology Design for Disturbance Minimization in Power Grids

The transient response of power grids to external disturbances influences their stable operation. This paper studies the effect of topology in linear time-invariant dynamics of different power grids. For a variety of objective functions, a unified framework based on $H_2$ norm is presented to analyze the robustness to ambient fluctuations. Such objectives include loss reduction, weighted consensus of phase angle deviations, oscillations in nodal frequency, and other graphical metrics. The framework is then used to study the problem of optimal topology design for robust control goals of different grids. For radial grids, the problem is shown as equivalent to the hard "optimum communication spanning tree" problem in graph theory and a combinatorial topology construction is presented with bounded approximation gap. Extended to loopy (meshed) grids, a greedy topology design algorithm is discussed. The performance of the topology design algorithms under multiple control objectives are presented on both loopy and radial test grids. Overall, this paper analyzes topology design algorithms on a broad class of control problems in power grid by exploring their combinatorial and graphical properties.Comment: 6 pages, 3 figures, a version of this work will appear in ACC 201

GROWING UP IN IRELAND. KEY FINDINGS: COHORT ’08 AT 9 YEARS OLD. NO. 1 9-YEAR-OLDS AND THEIR FAMILIES. Cohort '08 November 2018

This series of Key Findings draws on information provided by the Cohort ‘08 9-year-old and his or her Primary Caregiver (usually the mother, and henceforth in this report referred to as the mother). The series is based on the 7,563 9-year-olds whose families participated in the study at ages 9 months, 3 years, 5 years and 9 years old. This Key Findings report is the first in a series on the lives of these children at 9 years of age. It focuses on the lives and circumstances of these 9-year-olds in post-recession Ireland, the financial situation of their families and changes in family structure over time. It also looks at the relationship with grandparents, out-of-school care for the children and the contribution the children make to family chores

GROWING UP IN IRELAND. KEY FINDINGS: INFANT COHORT AT 7/8 YEARS. NO. 3 SOCIO-EMOTIONAL DEVELOPMENT, RELATIONSHIPS AND PLAY

This is the third in a series of Key Findings from the fourth wave of data collection from the Infant Cohort in Growing Up in Ireland. The families of just over 11,100 infants were first interviewed between September 2008 and March 2009, when the child at the centre of the study was 9 months old. They were re-interviewed when the child was 3 years old and again at 5 years of age. In 2016, a fourth wave of data was collected from the child’s primary caregiver (mainly their mother1), through a postal survey when the child was 7/8 years old. This Key Finding focuses on reports of children’s socio-emotional development and their behaviour, social skills, family relationships and play activities. Children’s progress in developing social and emotional skills is important for coping with relationships at school and at home, as well as being an important part of their overall well-being

GROWING UP IN IRELAND KEY FINDINGS: COHORT ’98 AT 20 YEARS OLD IN 2018/19 NO. 2 PHYSICAL HEALTH AND DEVELOPMENT

This Key Findings report presents summary information on the lives and circumstances of the 20-year-olds from the fourth wave of interviews with Growing Up in Ireland’s older Cohort ’98 between August 2018 and June 2019. It provides the most recent data on key indicators of physical health such as self-reported health, chronic conditions and weight status. It also explores important health-related behaviours such as drinking, smoking and substance use, physical activity, and sleep. Topics relating to mental health and well-being are covered in Key Finding 3

GROWING UP IN IRELAND. KEY FINDINGS: INFANT COHORT AT 7/8 YEARS. NO. 1 SCHOOL AND LEARNING

This is the first in a series of Key Findings from the fourth wave of data collection from the Infant Cohort in Growing Up in Ireland. The families of just over 11,100 infants were first interviewed between September 2008 and March 2009, when the child at the centre of the study was 9 months old. They were re-interviewed when the child was 3 years old and again at 5 years of age. In 2016, a fourth wave of data was collected from the child’s primary caregiver (mainly their mother1) through a postal survey when the child was 7/8 years old. This Key Finding focuses on mothers’ reports of how their children were doing in terms of their schooling and learning. Children’s early experiences of the classroom, their transition to formal school and their acquisition of key skills such as literacy and numeracy typically have a lasting effect on their short- and long-term educational development. At the time of the postal survey 36% of the children in the study were 7 years old and the rest were 8 years old. At this stage, most of them had been in Primary School for 2-3 years. Overall, 69% started school in 2012 (mostly in September), the remainder in 2013. Just over 1% of the children were in Junior or Senior Infants, 32% were in First Class and 66% in Second Class. Just less than 1% were in third class, home-schooled or at a special school

GROWING UP IN IRELAND. KEY FINDINGS: COHORT ’08 AT 9 YEARS OLD. NO. 3 HEALTH AND PHYSICAL DEVELOPMENT. Cohort '08 November 2018

This series of Key Findings draws on information provided by the Cohort ‘08 9-year-old and his or her Primary Caregiver (usually the mother, and henceforth in this report referred to as the mother). The series is based on the 7,563 9-year-olds whose families participated in the study at ages 9 months, 3 years, 5 years and 9 years old. This Key Findings report is the third in the series from the latest round of data collection from Cohort ’08 and is the first report on the health and physical development of these children. It covers key health indicators as reported by the mother, such as general health, longstanding conditions and diet. It examines the children’s own reports of their physical activity as well as their measured weight status. In addition, it looks at how the health of the 9-year-olds varies by family circumstances and by the children’s health status at ages 3 and 5