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The paper's aim is to investigate the effects of shot peening (SP) on the bending fatigue limit of high‐strength steel containing an artificial semi‐circular slit.

SP and stress SP (SSP) were conducted on the specimens containing an artificial semi‐circular slit with a depth of a=0.1, 0.2 and 0.3 mm. Then, bending fatigue tests were conducted on the specimens.

The fatigue limit was improved by SP and SSP. In the case of SP and SSP specimens, the specimens with a semi‐circular slit under a=0.2 mm fractured outside the slit, and they had considerably high fatigue limits. Therefore, a semi‐circular slit with a depth of under a=0.2 mm could be rendered harmless by SP or SSP. It was found that the fatigue limit of specimens with a semi‐circular slit that received SP or SSP was determined by the threshold condition for non‐propagation of fatigue cracks that emanated from outside the slit. Whether the semi‐circular slit is rendered harmless or not is decided by the relationship between the stress intensity factor range of semi‐circular cracks and the threshold stress intensity factor range.

The proposed method can be applied to mechanical parts used in vehicles, aircraft and trains.

There are very few examples of evaluations of fatigue limits after SP in materials containing crack‐like surface defects. This study calcifies the effect of SP on the fatigue limit having crack‐like surface defects.

This paper aims to discuss the significance of teacher authorship (jissen kiroku) developed during jugyo kenkyu. Specifically, it explores the structural conditions of jugyo kenkyu that enabled the flourishing of jissen kiroku.

To find how jissen kiroku developed in jugyo kenkyu, this paper settled triad of authors-text-readers as the analytical perspective. Disputes through 1960s–1980s are adequate to inquire because it can elucidate how readers read jissen kiroku, which is typically challenging to observe.

Jissen kiroku is a powerful tool for semantically preserving, reconstructing and consolidating professional values and knowledge in jugyo kenkyu with deepening connoisseurship. Voluntary educational research associations (VERAs) encourage teachers to write and read jissen kiroku to develop their professionalism, which also helped develop exclusive semantics within the field. These developments were possible due to the public nature of jissen kiroku, disseminated to lesson study (LS) actors, thereby strengthening discussions both inside and outside VERAs.

The paper proposes shift in views on educational science and emphasizes authorship as authority in that professionalism of teaching can be protected and elevated through authoring.

The significant roles of writing practice have not been explored enough. This paper finds the value of authorship in terms of public nature and openness to all teachers which enable the enhancement of professionalism of the LS field.