Calculations for AP1000 nuclear power plant SGTR accident based on RELAP5/mod 3.3 program
AP1000 nuclear power plant model is founded via RELAP5/mod 3.3 program in detail. Refer to SGTR accident basic assumptions in the safety analysis report, calculations for AP1000 nuclear power plant SGTR accident are carried out. And through comparison between the result got and the result from safety analysis report calculated by LOFTTR2 program, the two results are very consistent. It's found that even if the operators do not interfere, AP1000 nuclear power plant protection systems and passive design measures will trigger an automatic response measures, it can terminate the SG heat transfer tube leaking and make RCS be stable in a safe condition and to prevent SG overflowing and ADS actions occurring.
RCS cooldown and depressurization analysis of SGTR accident with SG safety valve stuck open
The Steam Generator Tube Rupture (SGTR) accident has been analyzed with RELAP5/MOD3 thermal hydraulic system analysis code under the conditions that the safety valve of affected SG is stuck open.The AFW is unavailable,and only one HPSI pump is available.It can be mitigated successfully if the operators take actions to cooldown and depressurize RCS within 150 min after the safety injection signal.The results show that the active core is covered by coolant before the break flow is terminated with the balance between primary and secondary side of affected SG at atmospheric pressure.
Child Poverty in the United States: A Tale of Devastation and the Promise of Hope.
The child poverty rate in the United States is higher than in most similarly developed countries, making child poverty one of America's most pressing social problems. This article provides an introduction of child poverty in the US, beginning with a short description of how poverty is measured and how child poverty is patterned across social groups and geographic space. I then examine the consequences of child poverty with a focus educational outcomes and child health, and three pathways through which poverty exerts its influence: resources, culture, and stress. After a brief review of the anti-poverty policy and programmatic landscape, I argue that moving forward we must enrich the communities in which poor families live in addition to boosting incomes and directly supporting children's skill development. I conclude with emerging research questions.