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The flow field in highly turbulent premixed combustion has been examined, using a cyclone-jet combustor. The shear-strain rate is obtained by PIV system. Results show that, in combustion field, mean axial velocity does not decay along center axis and RMS fluctuation velocity is much lower, compared with those in cold flow. The reaction zone detected by an ion probe well corresponds to region of large shear-strain rate. In combustion, turbulence is small around reaction zone to have the undiminished jet velocity, which leads to an increase in length of potential core, although the flame generated turbulence is observed through flow expansion.

Deformation behaviors of polycrystalline metals are quite complex, and we are not easy to directly investigate them; thus, analyses employing simple models such as bicrystals are required. In this study, we conducted crystal plasticity analysis of unidirectional tensile tests, using compatible-symmetric-type bicrystal models with the not-inclined grain boundary and incompatible-type bicrystal model with the inclined grain boundary; we investigated changes in patterns of geometrically necessary dislocation (GND) bans and the density of GNDs in the initial deformation. In the condition where the grain boundary contacted with the constrained faces, GND bans were formed and the distribution was changed with changing the inclination angle α of the grain boundary. In contrast, GNDs were not localized in high density in the condition where the grain boundary contacted with the free surfaces; the changes were caused by two-reasons: one was changes of compatibility of the bicrystal model with changing the inclination angle α, and the other was that deformation shapes of the bicrystal model under tensile loading were changed with changing the inclination angle α and the deformation was constrained by the constrained faces. The compatibility of and average density of GNDs in the bicrystal model could be estimated using differences of components of Schmid tensors between the crystal grains.

A cellular manufacturing system is a kind of lean and flexible manufacturing systems in which a worker or a group of workers carry out all assembly processes of a product. Assembly times of workers are generally improved in an exponential manner by repeating same assembly processes. However, the workers in the cellular manufacturing system are not provided with enough time to learn the assembly processes, since product mixes and production volumes are changeable in a short period of time. The objective of this study is to propose a work instruction system for untrained workers in assembly cells to understand the assembly processes quickly and reduce their assembly times of products without repeating same assembly processes. This study firstly records workers' assembly processes by using video equipment and analyzes the learning processes of the workers in order to propose an effective strategy for the workers to reduce the assembly processes in the cellular manufacturing system. According to the proposed strategy, a prototype of a work instruction system is developed for untrained workers in assembly cells. The prototype system provides graphical user interfaces explaining the information of assembly processes for the workers to facilitate understanding the assembly processes. Some experiments are carried out for assembling same toy cars built with Lego blocks in order to evaluate the effectiveness of the developed work instruction system. Experimental results of the proposed work instruction system are compared with the ones of a simple work instruction system. Through the comparison, it is recognized that the proposed work instruction system is superior to the simple work instruction system from the viewpoint of the reduction of assembly times. At the last part of this study, we propose a prediction method of assembly times of workers by measuring biological information as a heart rate, in order to carry out dynamic production management through the work instruction system.

Cellular manufacturing systems are well known as flexible manufacturing systems for assembly processes. Single workers carry out all assembly processes of products in the typical cellular manufacturing systems. The cellular manufacturing systems are required to cope with dynamic changes of product mix and production volumes. The workers are not able to be trained by repeating same assembly processes. The objective of this study is to propose a work instruction system for workers to understand the assembly processes quickly and reduce their assembly times of products without repeating same assembly processes. According to the learning curve of workers, it is important that the assembly time should be reduced from the first time the workers assemble the products in order to increase the productivity of cellular manufacturing systems. This study firstly records workers' assembly processes by using video equipment and analyzes the learning processes of the workers in order to propose an effective strategy for the workers to reduce the assembly processes in the cellular manufacturing systems. According to the proposed strategy, a prototype of a work instruction system is developed for an assembly cell. The prototype system provides a graphical user interface explaining the information of assembly processes for the workers to facilitate understanding the assembly processes. Some experiments are carried out for assembling a toy car built with Lego blocks in order to evaluate the effectiveness of the developed work instruction system. Experimental results of the proposed work instruction system are compared with the ones of a simple work instruction system. Through the comparison, it is recognized that the proposed work instruction system is superior to the simple work instruction system from the viewpoint of the reduction of assembly times.