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This paper aims to investigate global pressure fluctuations in compressible transitional flows in a low-pressure turbine cascade because of variations in the free-stream turbulence and its interaction with the boundary layers.

Transition process resolving numerical simulations are performed with different types of inflow turbulence. The unsteady three-dimensional fully compressible Navier–Stokes equations are solved using a sixth-order compact difference and a tenth-order filtering method. First, simulations of both K-regime and bypass transitions are conducted for a flat plate boundary layer to validate the use of the filter in computing different transition routes. Second, computations of the cascade flows are conducted. Cases of no free-stream turbulence, isotropic free-stream turbulence of 5 per cent and wakes from an upstream cylinder are compared. For wakes, variations in wake trajectory depending on the cylinder blade relative position are also taken into account.

The different transition routes are successfully reproduced by the present method even with strong filtering. When feedback phenomena occur near the trailing edge, high-frequency oscillations dominate in the flow field. Low-frequency oscillations become dominant when the blade boundary layer becomes turbulent. Thus, the effects of the free-stream turbulence and its interaction with the boundary layer appear as changes in the global pressure fluctuation.

The free-stream turbulence qualitatively affects global pressure fluctuations, which become a medium to convey boundary-layer information away from the cascade.

The purpose of this paper is to explain a new scandal ingredient in Japanese politics called sontaku. This word refers to cases when officials grant special treatment to a project because they believe they are acting in accordance with the wishes of an associated powerful person.

This paper describes the specific construction of major scandals involving sontaku from 2017 based primarily on newspaper accounts, examines the consequences of these scandals for politicians and bureaucrats, and discusses their implications for combating corruption in Japan.

The scandals after 2017 damaged to some extent the public support for the current Japanese administration and influenced the prime minister's decision to call a snap election. The scandals also highlighted systematic problems in the bureaucracy and motivated the government to reform laws concerning the management of public documents.

This paper will be useful to scholars and policy makers interested in studying the causes and consequences of scandals and political corruption in Japan.