1,178 research outputs found
Investigations on the Problem of Moisture Absorption13; by Kevlar Fibres
Kevlar fibres are know, to have affinity for moisture. We have investigated (i) the effect of relative humidity (RH) of ambient atmosphere and ( ii ) the effect of crystallinity of fibres on the process of moisture uptake.13; For RH values ranging fran 3 to 80% variation of moisture content of initially dry fibres with time has been measured. It is found that saturation moisture content varies with RH value. Specimens in which crystallinity has been reduced by apropriate treatmrent exhibit a marked increase in moisture content.Experiments on the effect of soaking the fibres in water at 26xB0;C and 98xB0;C have also been carried out. The site of ITOisture absorption has been studied using X-ray of dry Kevlar 49 fibres and those with clifferent levels13; of misture content. The results suggest that water molecules do not enter the unit cell
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A Profile of Disconnected Young Adults in 2010
The purpose of this report is to highlight a growing segment of the population who are arriving at young adulthood disconnected from the main pathways leading to economic independence. Arriving at young adulthood in a state of disconnection can have consequences for both young adults and the larger society. Young adults who have low educational attainment or who are out of school or unemployed for extended periods of time may be more likely to engage in delinquent behavior, turn to illegal activities as a source of income, and be incarcerated. The consequences of disconnection may also result in long-term penalties, such as underemployment and lower earnings over the life course. Young adults disconnected for three or more years are about 14 times more likely to be poor and earn about two and one half times less in earnings and are about two to three times less likely to be employed full-time than young adults who had never been disconnected. Disconnectedness experienced during young adulthood may also have serious health consequences. Research shows that different components of disconnectedness, such as having less than high school education or being unemployed is associated with suboptimal health and mental health outcomes. Furthermore, disconnected young adults are more likely to rely on some form of public assistance. Thus, the costs of disconnection to government can include increased transfer payments and social support expenses as well as a decrease in tax revenues from their lack of participation in the labor market. In short, this population deserves our attention given the long-term consequences being disconnected can pose for a successful transition to adulthood
Tackling India’s deepening gender inequality during COVID-19
As India slowly re-opens its economy following its emergency national measures to contain the spread of the novel coronavirus, Kalyani Raghunathan (International Food Policy Research Institute (IFPRI), New Delhi) and M Niaz Asadullah (University of Malaya, Malaysia) explain how India’s already high levels of gender inequality will deepen thanks to the pandemic
Tribological Properties of Polymer Composites Using Non Traditional Optimization Technique: a review
Specific wear rate of composite materials plays a significant role in industry. The processes to measure it are both time and cost consuming. It is essential to suggest a modeling method to predict and analyze the effectiveness of parameters of specific wear rate. Nowadays, computational methods such as Grey Relational Analysis (GRA), Artificial Neural Network (ANN), Fuzzy Inference System (FIS) and adaptive neuro-fuzzy inference system (ANFIS) are mainly considered as applicable tools from modeling point of view. The objective of using ANN, ANFIS is also to apply this tool for systematic parameter studies in the optimum design of composite materials for specific applications. In the present review, various principles of the neural network approach for predicting certain properties of polymer composite materials are discussed. The aim of this review is to promote more consideration of using GRA, ANN and ANFIS in the field of polymer composite property prediction and design
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Poor Children by Parents' Nativity: What Do We Know?
Immigration in the United States has held a longstanding and transformative role in shaping the country's social and economic landscape. State and local policies have, likewise, responded to the changing presence and composition of immigrants in American society. Yet, significant gaps in policies that address the unique experience of children in immigrant families still remain. As the number of children of immigrant parents increases, policies that meet their needs in areas such as education, health care, and economic security will become necessary. Currently, 17.2 million children residing in the U.S. have a parent who is foreign-born and 4.2 million children of immigrant parents are poor. High poverty rates among children of immigrant parents, coupled with unique social and economic challenges, make them particularly disadvantaged when compared with children of native-born parents. This poses a significant policy challenge, as poverty and other material hardships can have deleterious effects on a child's long-term health and well-being. More importantly, as this brief suggests, children of immigrant parents experience poverty that is different from poor children of native-born parents. For example, poor children of immigrant parents are more likely than their native-born counterparts to live in households where at least one parent works full-time, year-round. Moreover, poor children of immigrant families are less likely to receive food stamps than poor children of native-born parents. These findings suggest that child poverty in immigrant families is not necessarily linked to joblessness; rather, it is more closely connected to low-wage work and barriers to valuable work supports. Examining the landscape of poverty among children of immigrant parents will help to identify policy interventions that support healthy development and long-term economic security. Research suggests that children not only differ by the nativity of their parents (native- versus foreign-born), but that children of immigrant parents are themselves a diverse population. Studies show that duration of stay within the U.S. plays a critical role in determining long-term health well-being among children of immigrant parents. This brief takes into consideration the diversity among children of foreign- born parents by not only considering whether parents were born in the U.S. or abroad, but by also considering how long foreign-born parents have resided in the U.S. This is an important distinction when examining differences among children by parents' nativity. Thus, the purpose of this brief is to examine differences among children of native-born parents, children of recent immigrant families, and children of established immigrant families across a range of socio-demographic characteristics. Promoting positive outcomes for young children in immigrant families requires a deeper understanding of the population itself. To this end, the brief provides a more nuanced look at poor children living with immigrant parents by expanding the definition of the immigrant experience to include not only parents' nativity but also their duration of stay in the U.S
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Basic Facts About Low-income Children, 2009: Children Under Age 6
Children represent 25 percent of the population. Yet, they comprise 36 percent of all people in poverty. Among children, 42 percent live in low-income families and nearly one in every five live in poor families. Young children under age 6 appear to be particularly vulnerable with 46 percent living in low-income and 24 percent living in poor families. Winding up in a low-income or poor family does not happen by chance. There are significant factors related to children's experiences with economic insecurity, such as race/ethnicity and parents' education and employment. This fact sheet describes the demographic, socioeconomic, and geographic characteristics of young children and their parents — highlighting the important factors that appear to distinguish low-income and poor children in this age group from their less disadvantaged counterparts
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Basic Facts About Low-income Children, 2009: Children Aged 6 through 11
Children represent 25 percent of the population. Yet, they comprise 36 percent of all people in poverty. Among children, 42 percent live in low-income families and 21 percent live in poor families. Among children ages 6 through 11 in middle childhood, 42 percent live in low-income families and 20 percent live in poor families. Winding up in a low-income or poor family does not happen by chance. There are significant factors related to children's experiences with economic insecurity, such as race/ethnicity and parents' education and employment. This fact sheet describes the demographic, socioeconomic, and employment characteristics of children in middle childhood and their parents — highlighting the important factors that appear to distinguish low-income and poor children in this age group from their less disadvantaged counterparts
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Basic Facts About Low-income Children, 2009: Children Under Age 18
Children represent 25 percent of the population. Yet, they comprise 36 percent of all people in poverty. Among children, 42 percent live in low-income families and approximately one in every five live in poor families. Winding up in a low-income or poor family does not happen by chance. There are significant factors related to children's experiences with economic insecurity, such as race/ethnicity and parents' education and employment. This fact sheet describes the demographic, socio-economic, and geographic characteristics of children and their parents — highlighting the important factors that appear to distinguish low-income and poor children from their less disadvantaged counterparts
Experimental Analysis Of Rotor Blade In Wind Turbine Using Composite Materials With Natural Fiber
Rotor blades are a critical structural component of the tidal turbine since they are responsible for harvesting the kinetic energy of the water and transmitting it through the main drive train to the generator. At hand the rotor blades are manufactured using the materials like Conventional Steels and Aluminium Alloys. With the use of these existing materials it results in relatively low fracture toughness in high strength conditions, limited performance at elevated temperature. One of the main drawback of steel is suspected to corrosion and it also loses its properties at high temperatures. To overcome this issue Composite Material is being used. Rotor blade is made up of composite materials. The materials are glass fiber epoxy and natural fiber(sugar cane fiber) with the composition 10% of natural fiber and 90% of glass fiber epoxy. The modeling of the Rotor blade is carried out in SOLID WORKS and analysed using ANSYS FLUENT, Also the rotor blade is fabricated by HAND LAY-UP METHOD. The mechanical properties are tested. The results are validated
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