An analytical model of the sound power radiated from a flat plate airfoil of infinite span in a 2D turbulent flow is presented. The effects of stagger angle on the radiated sound power are included so that the sound power radiated upstream and downstream relative to the fan axis can be predicted. Closed-form asymptotic expressions, valid at low and high frequencies, are provided for the upstream, downstream, and total sound power. A study of the effects of chord length on the total sound power at all reduced frequencies is presented. Excellent agreement for frequencies above a critical frequency is shown between the fast analytical isolated airfoil model presented in this paper and an existing, computationally demanding, cascade model, in which the unsteady loading of the cascade is computed numerically. Reasonable agreement is also observed at low frequencies for low solidity cascade configurations.

Early indications suggest that the appointment of General Yaþar Büyükanýt as chief of the Turkish general staff (TGS) at the end of August 2006 marked a new era in civil‐military relations in the country. Yet it would be a mistake to see the military's more forthright attitude under Büyükanýt simply as a return to the past. Civil‐military relations in Turkey have always been characterized by a combination of continuity and change. Both the legal basis for and the TGS's own perceptions of the role and responsibilities of the military have remained unchanged for over 70 years. However, the extent and the manner in which the military has influenced politics have always varied. In recent years the TGS's ability to ensure that government policy remains within acceptable parameters has been primarily based on its public prestige rather than the prospect of a full‐blooded military coup. Although the TGS has always been the most respected institution in the country, the Turkish public's willingness to tolerate, or even to encourage, its assumption of a more active political role has traditionally varied according to changes in the prevailing domestic political circumstances: falling during times of stability and confidence and rising during times of uncertainty. In early 2007 both the country and the government of the moderately Islamist Justice and Development Party (JDP) appeared to have lost momentum and direction. In such an environment, and in the continued absence of an eff ective political opposition, many Turks will once again look to the country's military to prevent the JDP from increasing its control over the apparatus of state, starting with the appointment of a new president in April 2007. To date the JDP has always backed down in the face of pressure from the TGS. However, whether it will continue to do so, and what the TGS can or will do if the JDP defies its warnings, currently all remain unclear.

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