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The purpose of this paper is to explore the stock market impact of supply chain disruptions for public companies in Japan. The impact in the USA and Japan are also compared.

Using event study on a data set comprising of disruptions announced by Japanese and US companies during year 2000-2013, the authors measure the stock price reaction to supply chain disruptions.

The study finds that the Japanese companies, in an 11-day window around disruption announcement, witness an average abnormal return of −0.61 percent, which is statistically significant. In comparison to the USA, this stock decline is qualitatively smaller, yet statistically indifferent. The abnormal return is found significant in the two days before disruption announcement. However, a follow-up study with a refined data set (where the event date is the earlier of the announcement or disruption date) does not find any significant abnormal return prior to the event date. This difference from US market suggests the possibility of insider trading. Factors such as book-to-market ratio, industry type, and market capitalization did not affect the stock decline.

The research is limited to a data set from Japan and the USA. Further generalization of findings may need studies focused on other countries.

The results are of interest for supply chain managers. The results should also help global investors in making investment decisions.

Most supply chain disruptions management research is focused on companies in western countries. The paper is the first to test the impact of supply chain disruptions in Japan.

When handling small-sized shafts and holes, achieving optimal safety, size compatibility and shape adaptability using rigid grippers presents significant problems. Recent advancements have introduced soft end-effectors that offer enhanced safety and adaptability for gripping parts. However, these soft end-effectors often struggle to maintain the necessary gripping positional accuracy. The purpose of this paper is to design a soft end-effector specifically engineered to address these problems, combining precise gripping capabilities with improved safety, positional accuracy and adaptability to the size and shape of fragile, small-sized components.

A soft finger with multilayer decreasing drive air chambers is designed to achieve the finger bending increasing from the root to the tip of the finger to improve the flexibility of the fingertip. Additionally, a three-finger self-centering configuration is employed, coupled with an expandable structure to increase the gripping range. Furthermore, a theoretical mathematical model of the finger is established. The physical prototype is manufactured and subjected to experimental testing, including gripping tests on small-sized, fragile shaft holes, to validate its operational performance.

The grasping experiments confirm that the designed end-effector can maintain coaxial positioning and meet adaptability requirements when handling fragile components with small-sized shaft holes. Furthermore, the addition of expanding palm structure increases the gripping attitude and enriches the application scene and gripping space.

The design of multilayer decreasing air chamber structure to solve the problem of poor gripping stability and low positional accuracy of soft manipulator; the expandable palm design is introduced to enhance gripping space; and solved the problem of gripping accuracy in the assembly of fragile parts with small-size shafts and holes.