The Political Economy of Fiscal Policy

If there has been a dominant trend in the evolution of the modern industrial societies of this century it has been the growing importance of government in the allocation of social resources. It is important that we appreciate the fundamentally political nature of the formation of government economic policy. This survey reviews and assesses our present understanding of how the political system might shape a nation's fiscal policy. Our approach is eclectic, drawing both from economics and political science, and decidedly micro-analytic in its orientation. From economics we adopt the perspective of utility maximizing agents and the analytics of trade, agreement, and market failure. From political science we learn just how and when these individual agents might act collectively to provide public goods, redistribute income, or issue government debt. Together the micro-analytics of economics and political science form the core theory of the 'new' political economy and provide a framework for understanding the emergence, and the performance, of governments. There is no more important test for the new discipline than providing a compelling explanation for the formation of fiscal policy in democratic societies.

Candidate proof mass actuator control laws for the vibration suppression of a frame

The vibration of an experimental flexible space truss is controlled with internal control forces produced by several proof mass actuators. Four candidate control law strategies are evaluated in terms of performance and robustness. These control laws are experimentally implemented on a quasi free-free planar truss. Sensor and actuator dynamics are included in the model such that the final closed loop is self-equilibrated. The first two control laws considered are based on direct output feedback and consist of tuning the actuator feedback gains to the lowest mode intended to receive damping. The first method feeds back only the position and velocity of the proof mass relative to the structure; this results in a traditional vibration absorber. The second method includes the same feedback paths as the first plus feedback of the local structural velocity. The third law is designed with robust H infinity control theory. The fourth strategy is an active implementation of a viscous damper, where the actuator is configured to provide a bending moment at two points on the structure. The vibration control system is then evaluated in terms of how it would benefit the space structure's position control system

Understanding the Democratic Transition in South Africa

South Africa’s transition from apartheid to democracy stands as one of the past century’s most important political events. The transition has been successful to this point because the new constitution adopted a form of federal governance that has been able to provide protection for the economic elite from maximal redistributive taxation. Appropriately structured, federal governance creates a “hostage game” in which the majority central government controls the tax rate but elite run province(s) control the provision of important redistributive services to a significant fraction of lower income households. At least to today, the political economy of South Africa has found a stable equilibrium with less than maximal redistributive taxation. Moreover, the move to a democratic federalist system has improved the economic welfare of both the white minority and the black majority. Whether the federal structure can continue to check maximal taxation depends crucially upon the rate of time preference of the majority and their demands for redistributive public services. A new, impatient and more radical majority (ANC) party threatens the current equilibrium.

Fiscal Federalism in Europe: Lessons From the United States Experience

The existing political and legal institutions of fiscal policy-making are under challenge. As the United States and the eastern European and Soviet states experiment with policy decentralization, the states of western Europe are looking to a more centralized policy structure via the E.E.C.. This paper seeks to raise issues of importance to all such reform efforts--notably, the need to consider, and balance, the inefficiencies of fiscal policy decentralization (spillovers and wasteful fiscal competition) against the inefficiencies of fiscal policy centralization (policy cycles and localized 'pork barrel' spending and taxes). The need to develop new fiscal policy institutions emphasizing voluntary agreements and responsive 'agenda-setters' is stressed.

Vibration suppression and slewing control of a flexible structure

Examined here are the effects of motor dynamics and secondary piezoceramic actuators on vibration suppression during the slewing of flexible structures. The approach focuses on the interaction between the structure, the actuators, and the choice of control law. The results presented here are all simulated, but are based on experimentally determined parameters for the motor, structure, piezoceramic actuators, and piezofilm sensors. The simulation results clearly illustrate that the choice of motor inertia relative to beam inertia makes a critical difference in the performance of the system. In addition, the use of secondary piezoelectric actuators reduces the load requirements on the motor and also reduces the overshoot of the tip deflection. The structures considered here are a beam and a frame. The majority of results are based on a Euler Bernoulli beam model. The slewing frame introduces substantial torsional modes and a more realistic model. The slewing frame results are incomplete and represent work in progress

Control of a flexible planar truss using proof mass actuators

A flexible structure was modeled and actively controlled by using a single space realizable linear proof mass actuator. The NASA/UVA/UB actuator was attached to a flexible planar truss structure at an optimal location and it was considered as both passive and active device. The placement of the actuator was specified by examining the eigenvalues of the modified model that included the actuator dynamics, and the frequency response functions of the modified system. The electronic stiffness of the actuator was specified, such that the proof mass actuator system was tuned to the fourth structural mode of the truss by using traditional vibration absorber design. The active control law was limited to velocity feedback by integrating of the signals of two accelerometers attached to the structure. The two lower modes of the closed-loop structure were placed further in the LHS of the complex plane. The theoretically predicted passive and active control law was experimentally verified

Relative efficacies of GPR and EM-31 compared to traditional soil investigation techniques on a loess : Tertiary deposits in Southwest Tennessee

Remote sensing technology such as ground penetrating radar (GPR) and electromagnetic induction (EMI) have great promise as soil investigation tools. For certain applications, using tools such as these can potentially provide a more complete picture of the sub-surface than traditional soil investigation techniques. In order to evaluate the efficacy of such tools, GPR and EMI data were compared to traditional soil investigation data on loess / alluvium / Tertiary deposits in southwest Tennessee. The objectives of this study were to i) conduct a complete soil morphological, chemical, and physical characterization of a landscape at the Ames Plantation; ii) classify the soils to the family level of soil taxonomy; iii) conduct non-intrusive soil investigation using both GPR and EMI; and iv) compare remote sensing data to the traditional soils data. A total of nine pedons were sampled on field #75 at the Ames Plantation. Sites were sampled on a 30.5-m X 30.5-m grid. Each site was spaced 15.25 m apart. Sampling depths ranged from 2.5 m to 3.0 m. Standard soil survey laboratory methods were performed on all sites for particle size, cation exchange capacity, exchangeable bases, free iron oxides, easily reducible manganese, KCl extractable aluminum, pH, total elemental analysis, total carbon, organic carbon, and BaCl2-TEA extractable acidity. Bulk density was determined using the Varsol method. Saturated hydraulic conductivity was measured in situ using an Amoozemeter. Soil physical data were analyzed and grouped using Ward\u27s Minimum Variance Clustering Analysis. Non-intrusive mapping was completed using a Trimble Ag. GPS™ 132, a Geonics EM-31™, and an SIR system 10-A™ GPR unit. Maps of bulk soil conductivity to the 3-m and 6-m depths as well as GPR images were produced. Sites were clustered based upon similarities seen in the remote sensing data. Final groupings from both techniques were analyzed for agreement using SAS. All sites were located on an upland position with loess over alluvium over Tertiary sand parent material sequence. Loess thickness ranged from 90 cm to 144 cm. Alluvium thickness ranged from 82 cm to 151 cm. Pedons sampled at sites four and seven did not reach the Tertiary sand. Carbon distribution was somewhat irregular throughout the alluvium at all sites except site six. A fining upward sequence was seen throughout the alluvium at all sites. Data were insufficient to distinguish different loess depositions. All soils were classified as Ultic Hapludalfs. Statistical analysis of soil morphological and physical data yielded the following groups: 1) 1, 3, 4, 7; 2) 5, 6, 8; 3) 2, 7; site 9 was not grouped. GPR and EM-31 data produced the following groups: 1) 1, 3 ,4, 7; 2) 6, 8, 9; 3) 2, 5. Agreement between the groupings was strong, K = .8 ± 0.34. The GPR and EM-31 were effective for detecting slight variations in physical properties and grouping soils based on these differences in soils formed in loess/alluvium/Tertiary sands

Controlling flexible structures with second order actuator dynamics

The control of flexible structures for those systems with actuators that are modeled by second order dynamics is examined. Two modeling approaches are investigated. First a stability and performance analysis is performed using a low order finite dimensional model of the structure. Secondly, a continuum model of the flexible structure to be controlled, coupled with lumped parameter second order dynamic models of the actuators performing the control is used. This model is appropriate in the modeling of the control of a flexible panel by proof-mass actuators as well as other beam, plate and shell like structural numbers. The model is verified with experimental measurements

Static and dynamic characteristics of a piezoceramic strut

The experimental study of a piezoceramic active truss is presented. This active strut is unique in that the piezoceramic configurations allow the stroke length of the strut not to be dependent on the piezoceramic material's expansion range but on the deflection range of the piezoceramic bender segment. A finite element model of a piezoceramic strut segment was constructed. Piezoceramic actuation was simulated using thermally induced strains. This model yielded information on the stiffness and force range of a bender element. The static and dynamic properties of the strut were identified experimentally. Feedback control was used to vary the stiffness of the strut. The experimentally verified model was used to explore implementation possibilities of the strut