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This work is the extended version of a paper presented at the conference HMM2021, about the history of mechanical engineering. First, the initial cultural and industrial steps in the robotic field in Japan are introduced, to display the beginning of this interlaced path, before WW2; then, in the context of the aftermaths of the war, some famous anime heroes are presented as ancestors of the coming mecha anime series. The rising research in the field of robotics and more generally the developments of contemporary Japanese automation industry are then drawn, as a technological substrate for mecha conception. In particular, Masahiro Mori studies are taken into consideration to identify an actual robot design pattern to apply to the following comparative description and examination of the different mecha; finally, thanks to this analysis, the common breeding ground whence robotics and mecha (and their reciprocal influences) arise, is outlined. [ABSTRACT FROM AUTHOR]

Lists several titles of original research papers published in the Japanese journals "Journal of the Society of Powder Technology, Japan" and "Powder Science & Engineering."

As an ancient paper craft originating from Japan, origami has been naturally embedded and contextualized in a variety of applications in the fields of mathematics, engineering, food packaging, and biological design. The computational and manufacturing capabilities today urge us to develop significantly new forms of folding as well as different materials for folding. In this paper, by allowing line cuts with crease patterns and creating folded hinges across basic structural units (BSU), typically not done in origami, we achieve a new multiprimitive folding framework such as using tetrahedral, cuboidal, prismatic, and pyramidal components, called “Kinetogami.” “Kinetogami” enables one to fold up closed-loop(s) polyhedral mechanisms (linkages) with multi-degree-of-freedom and self-deployable characteristics in a single build. This paper discusses a set of mathematical and design theories to enable design of 3D structures and mechanisms all folded from preplanned printed sheet materials. We present prototypical exploration of folding polyhedral mechanisms in a hierarchical manner as well as their transformations through reconfiguration that reorients the material and structure. The explicit 2D fabrication layout and construction rules are visually parameterized for geometric properties to ensure a continuous folding motion free of intersection. As a demonstration artifact, a multimaterial sheet is 3D printed with elastomeric flexure hinges connecting the rigid plastic facets. [ABSTRACT FROM AUTHOR]

In this paper, we analyze and compare two didactical designs for introducing primary school pupils to proportional reasoning in the context of plane polygons. One of them is well-documented in the literature; the other one is based on our own data and is accordingly presented and discussed in more detail in this paper. The two designs come from different cultural and intellectual environments: lesson study in Japan (implicitly based on the “open approach method”) and “didactical engineering” in France (based on the theory of didactical situations). The general aim of our paper is to compare these two environments and their approaches to didactical design, basing our discussion on the concrete designs mentioned above. Clear differences among them are presented, while we also identify links which hold potential for integrating research and practice. [ABSTRACT FROM AUTHOR]

After eminent thinkers in the 1960s submitted critical views on technology, some philosophers of technology extended their macro perspectives. Since then, many historians and sociologists of technology steadily marginalized their general claims through richly empirical, constructivist case studies of concrete engineering processes. Some recent efforts have begun to bridge these two diverging orientations. This paper participates in such efforts with a case study of relationships between macro cultures and engineering processes. It shows that behind the adoption of systems engineering by engineers and managers who led the Apollo programme was a macro current of social values in the USA. Post-war American society saw the rise of highly individualistic social norms that valued mobility, meritocracy and clear-cut contractual working relationships. Such norms triumphed most conspicuously in the federal government during the 1960s. Engineers and managers at the National Aeronautics and Space Administration (NASA) headquarters, who tended to share such values, refined the formalized, depersonalized methods of systems engineering, which enabled them to perfect space technology. In order to show such a correlation between macro values and micro practices, this paper draws a comparison between engineering communities in different cultural settings in the USA and Japan. This paper thus explores the macro social environment that gave rise to systems engineering, which, in turn, continues to function as a skeletal structure for our technological society today. [ABSTRACT FROM AUTHOR]

The qualitative description of rock masses by means of classification systems and subsequent correlation to establish engineering quantities or design parameters has become one of the most challenging topics in rock engineering. Many rock mass classification systems have been proposed for rock masses with the consideration of a particular rock structure and/or specific purposes. Therefore, direct utilization of these systems, in their original form, for the characterization of complex rock mass conditions is not always possible. This is probably one of the reasons why rock engineers continue to develop new systems or modify and extend current ones. The recent tendency is to obtain rock mass properties from the utilization of properties of intact rock and rock classification indexes, which have some drawbacks. In this study, it is aimed to propose a new rock mass quality rating system designated as Rock Mass Quality Rating (RMQR). This new rock mass rating system is used to estimate the geomechanical properties of rock masses. In the first part of this paper, the input parameters of RMQR and their ratings are given and discussed. In the second part, the unified formula proposed by the first author is adopted for the new rock mass rating system for estimating the rock mass properties and compared with the results of the in situ tests carried out in Japan and those estimated from some empirical relationships developed by other investigators, and the outcomes of these studies are presented and discussed. [ABSTRACT FROM AUTHOR]

• Ground response mechanism under different geometrical configurations of jacked rectangular pipe was investigated. • Higher jacking force is needed with increasing aspect ratio of the jacked rectangular pipe. • Square shaped cross-section design is conductive for deep and long-distance jacking construction. For rectangular pipe-jacking construction, the primary priorities of smooth construction include minimizing the ground response and designating the appropriate jacking force to achieve the best results in environmental protection and energy conservation. The geometric cross-section design of the jacking rectangular pipe and its engineering performances such as the ground surface displacement, the jacking force consumption, and the stress-bearing state are easy to be ignored in the field construction. In this paper, the ground response characteristics under four kinds of rectangular pipe aspect ratio (H/W) with the same utilization cross-section area were investigated by using the calibrated finite element method (FEM) based on a case study conducted in Japan. The theoretical jacking force of each pipe section design was calculated and compared to provide a reference for long-distance or large-section jacking conditions. The stress-bearing state of each pipe was considered under different buried depths. The results show that the ground surface response decreases while the jacking force increases with increasing the aspect ratios. Thus, a reasonable design of the rectangular pipe section should comprehensively consider the influence of geometric effects on the ground and its stress-bearing state during the jacking construction. The findings of this study provide a practical reference for the safe and economic design of the jacking rectangular pipe and engineering management. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents activities of the Architectural Institute of Japan (AIJ) on computational wind engineering, focusing on numerical prediction of wind loads on buildings. It discusses and evaluates current CFD techniques, including LES and modified RANS, for wind-resistant design of actual buildings. It also provides a guide for constructing a numerical model, including selection of a turbulence model, size of computational domain, required numerical discretization, etc. [Copyright &y& Elsevier]

It is well known that one drawback for stress-ribbon bridges can be that significant horizontal reactions at the abutment can be generated and that they have low flexural stiffness. The latter prevents them from being used as roadway bridges. A new hybrid structure of stress-ribbon deck and truss has been proposed and was adopted in the construction of Nozomi Bridge in Japan, a roadway bridge opened to traffic in 2003. Static and dynamic behaviours of the hybrid structure have been studied analytically and experimentally. The results show that the hybrid bridge has advantages over the stress-ribbon deck bridge as it generates much less horizontal force in suspension cables and has higher flexural stiffness, suitable for use as a roadway bridge, and that the hybrid bridge has advantages over the truss bridge since it can be constructed without extensive falsework and without large erection equipment. In this paper, at first, the hybrid structure is described, then analytical and test results are used to show its static and dynamic characteristics, and finally the construction of Nozomi Bridge is outlined. [ABSTRACT FROM AUTHOR]

Abstract: The ITER transitional arrangements (ITA) is conducted by the International Team (IT) with supports from participant teams (PTs). The Japanese Participant Team (JA-PT) has contributed to the ITA by sharing a lot of technical tasks to verify feasibilities of fabrication and quality control method in procuring ITER equipments and facilities. For examples, trial fabrications of Nb3Sn strands have been performed by the JA-PT with four potential suppliers, and it has already been confirmed that one of the strands produced by a certain supplier meet the ITER requirements. All strands produced by other suppliers will be fully qualified by the end of 2005. The trial fabrications of jackets for the central solenoid (CS), structural material for toroidal field coil, the partial mock-ups of the vacuum vessel (VV) and the shield blanket module are also ongoing to verify the feasibility of fabrications and quality inspections. Furthermore, the JA-PT has made several technical developments on neutral beam (NB) system to improve reliability in high voltage (1MV) insulation and in stable high current density operations over a long period. Design of equatorial EC launcher and some techniques towards reliable steady-state EC operation have been developed. The paper also describes other activities to confirm validity of the present design. [Copyright &y& Elsevier]

International comparisons of engineering graduate numbers are frequently used as indices of industrial development and measures of the responsiveness of the educational system to industrial requirements. Such comparisons make implicit assumptions about quality by assuming that like institutions or like qualifications are being compared. In this paper the concept of 'best practice' engineering education is derived from engineering manpower reports of German engineering education in order to address issues of both quantity and quality in comparing engineering education in Britain and Japan. Japan is found to have associated engineering education with relatively more prestigious institutions and to have attracted a higher proportion of more able male pupils to broad based engineering education compared to Britain. Yet there are some interesting differences between the model of 'best practice' engineering education based on Germany and Japanese practice, particularly in curricula, which underline the importance of the division of labour between education and employment in the education and training of engineers. Examining the responsiveness of educational systems through propositions derived from a model of 'best practice' rather than through simple output statistics underlines the importance of different patterns of institutional development, the role of the state, educational and occupational selection, and status within the curriculum for understanding the variety of contemporary engineering education. [ABSTRACT FROM AUTHOR]

During the past ten years the Soviet Bloc has designed, developed, and put into production a series of upward-compatible third-generation computers known as the Unified System or Ryad. This family is effectively a reverse engineering of the IBM S/360 system. Although backward by current Western and Japanese standards, the Unified System is of considerable technological, political, and economic importance. This paper is an attempt to present a comprehensive survey and analysis of the Ryad project. [ABSTRACT FROM AUTHOR]