LIGA process includes three processes as X-ray lithography, electroforming to fabricate metalic molds and replication, and can be fabricated nano and micro parts for various devices that it is difficult to product by conventional machining methods. A key technology which gathers mass-production efficiency in the LIGA process is micro-replication technology.We choiced hot embossing and injection molding methods for replication. For a demonstration, two kinds of Ni molds, a mesh pattern within a line width of 100 lm, and an aspect ratio of 1.0 and a mesh pattern within a line width of 40 lm, and an aspect ratio of 2.5, were prepared. These were produced with X-ray lithography and nickel electrofoming technique. In hot embossing, an experiment of micro-replication using polymethyl methacrylate (PMMA) and polycarbonate (PC) sheets succeeded. At injection molding, it could not transfer well with PMMA and PC, but injection temperature was set up highly, and it succeeded by cycloolefin polymer. Furthermore, we measured sidewall's surface roughness of microstructures produced at each steppes of the LIGA process, and it checked that the LIGA process had processing accuracy higher than a conventional machining method.

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The computational and simulation analysis of pull-out fiber reinforced concrete was investigated. The finite element analysis was used to make this modeling and analysis on this reinforced system and three parts (concrete matrix, the placed fiber reinforcement polymers (FRP), and resin layer) were studied. A constant load was directly applied on the free end of placed FRP and the deformation, von Mises stress, displacement, and strain of these three analyzed parts were obtained. Meanwhile, the specimen system of bonding strength and strain was calculated by the method of ABAQUS. The results showed that, with the constant load, the von Mises stress, deformation, and strain appeared in these three parts, and the maximum values in both FRP and resin layer were shown at the free end side, which provides an accurate description of the rupture mode.

The box frame is a common structure in modern furniture, especially for cabinets. Accordingly, the joint contact force of the frame is important in evaluating the stability of classified furniture. In this study, a new type of keyed joint was proposed to alter the dovetail joint used in box frame structures. The tensile strength of the dovetail joint and the keyed joint in the frame were evaluated, and the contact forces and failure modes of these two joints were compared. Three levels (T1, T2, and T3) were proposed for the ratio of groove depth (D) to inclined contact surface height (H), under the condition of the same joint spacing and inclination angle considering the effects of keyed joint size on the contact force. Meanwhile, experimental analysis was performed on both sides (S1 and S2) of the dovetail joint. Results showed that the contact force of the joint under the gluing condition decreased in the order of S2 > T2 > T3 > S1 > T1. In terms of failure modes, the keyed joint could be maintained in good condition, whereas failure of the dovetail joint always occurred at the root of the tenon in the S1 direction.

Compressive and tensile strengths were considered for a box connected by dovetail keys under different mortise-and-tenon sizes. Poplar wood modified by melamine resin (MF modified poplar wood) was chosen as the experimental material, and the experimental study was carried out on the box using the concentrated loading method. The results showed that the ratio (T) of hole depth to slope height had a significant effect on the structural strength of the box connected by dovetail keys when other dimensional parameters were the same. When T was equal to 75%, the compression and tensile strength of the box was the highest, and the joint had better recovery and deformation ability. When T` was equal to 50%, the box strength was the worst, and the joint damage was the most serious in both types of loading. In addition, the measurement standard of the displacement was determined through preliminary experimentation. The compression quantity was 8 mm, and the stretching quantity was 5 mm. The latter experiment showed the reliability of the pre-experiment.