Acoustic metamaterial has a periodic structure that contains a resonance system such as a massspring system and a Helmholtz resonator. Dynamic characteristic must be carefully designed so that the periodic structure realizes an extraordinary performance of a metamaterial. In this paper, a mathematical physical model of the unit cell that contains a Helmholtz resonator is constructed and the specifications of the unit cell structure are optimized to obtain an extraordinary sound transmission loss.

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Recent developments show that honeycomb structures built by a continuous production process can be successful in industrial applications at different scales (from nanosciences to aerospace applications) because of their material savings and low weight; while maintaining the mechanical properties required in the application. However, these properties cannot be well exploited when the three-dimensional shapes to be built have complex geometries because the theory supporting the production process is centered on an axial slice and two two-dimensional curves for the representation of the three-dimensional shapes. This work extends the range of applications of the technology by means of a new design methodology based on the constructive solids geometry (CSG) that allows combining the hexagonal honeycomb cell into complex three-dimensional structures by means of boolean operations while maintaining an optimal utilization of the material within a continuous production process.

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According to the Small and Medium Enterprise Agency, more than 50% of business owners over the age of 60 plan to close their business. In particular, about 70% of individual businesses replied that they plan to close their business. This is one of the causes of stagnation and decline in regional vitality, and there are similar issues in Wakayama prefecture. In this study, we have had some Interviews to the companies which succeeded in establishing a new business and analyzed by text mining. With the fact revealed by analysis, this paper reviews the supports to promote business continuity and starting new business In Wakayama Prefecture based on the characteristics of each of the three types of companies such as reborned in new businesses and fields, VB (Venture Business) and starting business after migration.

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We conducted a semi-structured interview with 17 Japanese workers about changes in productivity in teamwork due to telework. In the interview, we focused on changes in work, life, and consciousness of survey subjects before and after telework.

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In this chapter, we will study on the multifaceted approach by research cases. In the research cases, we took a multifaceted approach using M-GTA and text mining to the interview data on conflict coping between organization. As a result, we find that the theory / process constructed by M-GTA could be complemented by quantitative verification by text mining.

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This short paper attempts to present the process of deriving the analysis result diagram of M-GTA which has been described only as a representation of non-time-series motion, with more concrete process description based on past literatures and research by the developer of M-GTA, providing metaphor from natural science and system dynamics theory.

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Qualitative research methods, for example KJ Method or GTA are useful to acquire customer needs and issues before design phase. Diagrams and explanations are created as outputs by those qualitative research methodologies. However, the procedure to create diagrams are not clearly defended in those methodologies. In this research, the diagraming techniques in software engineering, for example Flowchart, State transition diagram, and Entity-Relationship Diagram are discussed with an aspect of parts of speech.

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