Ataru T. Nakagawa

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CAFE is the name of a network based environment now under development for supporting systematic creation, checking, verification, and maintenance of formal specifications. CAFE has an algebraic specification language called CafeOBJ as its main specification language, and adopts an algebraic specification paradigm as its foundation. CafeOBJ is a successor of(More)
A brake in which the magnetorheologic fluid (MRF) is used has a simple structure and good responsibility. Therefore, MR brake is expected to perform a good adaptability for human-coexistence system. Being applied in an ankle-foot orthosis, however, conventional MR brake is too large to fit. Then, in this study we developed a shear-type MR brake with multi(More)
A. Nakagawa (1991) showed hemispheric asymmetries during semantic processing of single English words. The right hemisphere passively maintained both strong and weak associations, whereas the left hemisphere maintained only strong associations when subjects were left free to attend. The present study extends the methodology to the study of Kanji characters.(More)
The purpose of this study is to develop a prosthetic ankle joint intelligently controlled by specially designed linear MR (magneto-rheological) brake. MR fluid changes its rheology depending on the intension of an applied magnetic field. The brake using MR fluid (we call it MR brake) has a simple structure and can control its braking force with a low(More)
Cafe is the name of an environment for systematic development of formal speci cations based on algebraic speci cation techniques. The concept of Cafe was conceived by the rst author around 1990 at ETL 1 as a successor of the OBJ language system. The development of Cafe has been supported by IPA 2 from 1992, and the rst version of CafeOBJ (a main speci(More)
We have described QuickDraw, a typical graphics package, using OBJ2, a powerful algebraic language now in the phase of experimental use as a specification language. The results testify the applicability of OBJ2 to some practical problem domains, as well as the premonitioned advantages the use of formal specification techniques brings. The work also sheds(More)
Stepwise refinement method can be formalised algebraically, using specification morphism. Algebraic schemes also oJTer a natural way, like that we have adopted, to modularise specifications in the shape of distinct sort sets. Our definition of stepwise refinement with modularity is a faithful rendition of system development processes, as is shown by the(More)
For a process model to be accepted by a variety of practitioners, it has to be flexible, in the sense that it can be easily and naturally adaptable to diverse software development scenes. It may, although not must, also be of help if it is derived evolutionary, in the sense that the model accepts the basic tenets of prevalent software practices with only(More)