We address the problem of enhancing mixing by means of boundary feedback control in 2D channel *ow. This is done by 6rst designing feedback control strategies for the stabilization of the parabolic equilibrium *ow, then applying this feedback with the sign of the input reversed. The result is enhanced instability of the parabolic equilibrium *ow, which leads rapidly to highly complex *ow patter...

It is well known that three momentum wheel actuators can be used to control the attitude of a rigid spacecraft and that arbitrary reorientation maneuvers of the spacecraft can be accomplished using smooth feedback. If failure of one of the momentum wheel actuators occurs, we demonstrate that two momentum wheel actuators can be used to control the attitude of a rigid spacecraft and that arbitrar...

mineral paragenesis of rodingitized basic rocks of iranian ophiolites are presented and metasomatic reactions between ca+2 bearing aqueous fluids issued during serpentinization of host ultramafic rock – with magmatic minerals of basic rocks leading to present paragenesis of rodingites are discussed. it is concluded that ca+2 rich aqueous fluid in equilibrium with serpentinite has high ca+2 chem...

Mineral paragenesis of rodingitized basic rocks of Iranian ophiolites are presented and metasomatic reactions between Ca+2 bearing aqueous fluids issued during serpentinization of host ultramafic rock – with magmatic minerals of basic rocks leading to present paragenesis of rodingites are discussed. It is concluded that Ca+2 rich aqueous fluid in equilibrium with serpentinite has high Ca+2 chem...

Spatial patterns of local climate feedback and equilibrium partial temperature responses are produced from eight general circulation models with slab oceans forced by doubling carbon dioxide (CO2). The analysis is extended to other forcing mechanisms with the Met Office Hadley Centre slab ocean climate model version 3 (HadSM3). In agreement with previous studies, the greatest intermodel differe...

corrective feedback (cf) and its different types have long absorbed many scholars and practitioners. as ellis (2009) mentioned some experimental studies need to be carefully designed to discover the relative effectiveness of each of these cf techniques. the goal of this qualitative study was to discover whether the employment of different cf strategies could bring about an attitudinal shift. to...

Reputation mechanisms offer an effective alternative to verification authorities for building trust in electronic markets with moral hazard. Future clients guide their business decisions by considering the feedback from past transactions; if truthfully exposed, cheating behavior is sanctioned and thus becomes irrational. It therefore becomes important to ensure that rational clients have the ri...

The paper addresses the two-fold rise in teacher-student ratio in the American K-12 school system in the post-World War II period accompanied by the evidence of a decline in the relative quality of teachers. We develop a dynamic general equilibrium framework for analyzing the teacher quantity-quality trade-off and offer an explanation to the observed trends. Our OLG model features two stages of...

Military strategists are increasingly recognizing that planned interventions sometimes fail to achieve their goals, especially in the long term, because planning is done with a limited view of possible outcomes rather than a whole-systems perspective. The systems modeling methodology of system dynamics is well-suited to address many of the dynamically complex problems that arise in the context ...

A tangible audio–visual interface based on the metaphor of balancing a ball on a tiltable track allows the measurement of human control movements under different conditions of sensory feedback. This specific scenario of human–system interaction forms an example for the definition of various measures of performance and quality of interaction. The dependence of these measures on specific configur...