Observations on the vibration of axially-tensioned elastomeric pipes conveying fluids

A study of the effect of axial tension on the vibration of a single-span elastomeric pipe clamped at both ends conveying fluid has been carried out both experimentally and theoretically. A new mathematical model using a penalty function technique and the method of kinematic correction and fictitious loads has been developed. The influence of flowing fluid and axial tension on natural frequencies and mode shapes of the system has been described using this model and compared with experimental observations. Linear and non-linear dynamic response of the harmonically excited pipe has also been investigated for varying flow velocities and initial axial tensions

When Sex Doesn't Sell - Political Scandals, Culture, and Media Coverage in the States

The determinants of media coverage of political scandals are examined through a content analysis of AP Wire stories in ten states from 1998 to 2005. Tests of the conventional explanations of the amount of media coverage demonstrate that political culture, institutional factors, and the prominence of the officials involved matter, but find only mixed evidence that scandal severity is an important factor. Contrary to assumptions, sexual scandals do not generate more media coverage than other types of exposés

Collective Action and the Mobilization of Institutions

Bias in the composition of interest communities is often explained by reference to variations in the collective action constraint facing voluntary and nonvoluntary organizations. But with the exception of literature on PAC formation, studies of direct institutional mobilization are rare. More often than not, their mobilization advantages vis-à-vis problems of collective action are simply assumed. This paper fills this gap by testing the collective action hypothesis on direct institutional mobilization. We argue that the PAC studies are flawed as tests of this hypothesis; they study the wrong mode of political activity and use selective samples and limited research designs. We develop a new test using state data on seven types of institutions to solve these problems. We also compare the collective action problem facing institutions to the related problems facing voluntary organizations. We find strong evidence of collective action problems in institutional mobilization, problems that make interest populations of nonvoluntary and voluntary organizations appear far more similar than commonly thought

The Strange Disappearance of Investment in Human and Physical Capital in the United States

Many scholars have argued that there are strong incentives for states to spend less money on redistributive or consumption programs, such as welfare, and more on developmental or investment programs, such as highways. Yet, over the last few decades, the proportion of state budgets allocated to expenditures intended to develop human and physical capital, specifically education and highways, has declined. In real terms, spending on virtually every government program has increased but expenditure increases to redistributive programs have been much greater than those to investment programs. Why this shift has happened despite theory predicting the contrary has not been adequately examined in a way that considers multiple developmental programs and multiple ways of conceptualizing spending over a substantial time period. We undertake this task in the following article using a large, cross-sectional time series data set of state budgeting toward K-12 education, higher education, and highways from 1965 to 2004. We test competing theories of the determinants of state spending using these data and then discuss the factors that we believe have led to the relative de-emphasis on developmental programs. We find that the most consistent predictors of state developmental spending patterns are federal grants, the state of the economy, and interstate and intrastate competition

Building the Reservoir to Nowhere: The Role of Agencies in Advocacy Coalitions

The purpose of the advocacy coalition framework is to explain policy change over time through an examination of the stability of advocacy coalitions within policy subsystems. Recently, scholars have confirmed that advocacy coalitions are held together by shared belief systems, specifically in distributive policy arenas. We contend that federal agencies, in distributive policy arenas, provide both the anchors and support systems for the development and maintenance of belief systems. This anchoring helps provide adequate resources, access to political institutions, ability to control administrative process, and/or the capacity to deliver public goods and services. We conducted an analysis of the policy changes that occurred during the implementation of the National Environmental Policy Act for the construction of the Bureau of Reclamation’s Animas-La Plata project. This is an example where administrators, through the management of information, were able to control the policy process. The analysis provides a needed replication of previous findings regarding policy change and offers new insights into how institutions are critical to subsystem stability over time

The unimportance of the spurious root of time integration algorithms for structural dynamics

Most commonly used second-order-accurate, dissipative time integration algorithms for structural dynamics possess a spurious root. For an algorithm to be accurate, it has been suggested that the spurious root must be small and ideally be zero in the low-frequency limit. In the paper we show that good accuracy can be achieved even if the spurious root does not tend towards zero in the low-frequency limit. This permits more flexibility in the design of time integration algorithms. As an example, we present an algorithm that has greater accuracy than several other dissipative algorithms even though for all frequencies its spurious root is non-zero. We also show that the degraded performance of the Bazzi-Ρ algorithm is not due to its non-zero spurious root.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50422/1/1640100803_ftp.pd