Poly Lactic-co-glycolic Acid (PLGA) is usually dissolved into dichloromethane (DCM) for generating PLGA particles. Meanwhile, polydimethylsiloxane (PDMS) is a material which has been widely used for fabrication of microfluidic device because of its low cost and simple manufacture for complex channels. However, DCM is easily absorbed by PDMS, thereby swelling the PDMS. To solve this problem, we used a new solvent, dimethyl carbonate (DMC), to dissolve PLGA and to generate PLGA particles via solvent evaporation. We fabricated a PDMS microfluidic device consisting of a cross junction by soft lithography to generate PLGA droplets. We successfully produced PLGA particles having a mean diameter of 49.7 µm and a coefficient of variation (CV) of 5.2% using this device.

Stereo lithography method can fabricate products with complicated shapes, but the material is limited to UV photopolymer. Mechanical strength is required to put the parts obtained by stereo lithography for practical use. Therefore, the carbon fibers are oriented along the desired direction in the UV photopolymer. In this study, we proposed the development of a method for orienting carbon fibers along the thickness direction of a structure using static electricity, and demonstrated this method.

Wire electrical discharge machining (WEDM) is a pervasive kind of electrical discharge machining (EDM) technology. Discharge reaction force caused by the discharge bubble acting on the wire electrode is considered as one of the reasons why the wire vibrates during machining. Even if there are some researches on the behaviors of the bubble in sinking EDM, there is still a vital demand of clarifying the behaviors of the bubble generated in the gap between the wire electrode and workpiece, because the geometry of the interelectrode gap in WEDM is quite different from that in sinking EDM. In this study, the deformation of the bubble boundary due to the complicated shape of the gap, and the oscillation of the bubble with the passage of time were clarified in WEDM. Thereby, the influence of the deformed bubble on the wire electrode vibration, which is significantly important to improve the machining accuracy, was discussed.

The LC generator has many advantages in electrical discharge machining (EDM). It can generate high open voltage for EDM gap and high discharge current pulse with short duration with very low voltage input. The shape of current pulse generated by the LC generator with higher rising speed shows superiority in machining with efficiency compared to the conventional RC generator. However, the pulse shapes of discharge current, relative peak value and duration of open voltage have not been investigated carefully. This paper aims to investigate the influenced parameters of the LC generator to analyze the discharge current and open voltage for EDM. The results of investigation are proved to match the real discharge conditions by experiments. Besides, due to the induced electromotive force of the LC pulse generator, the pulse duration of the open voltage is significantly short. Thus, discharge frequency of the LC generator is lower than the conventional generators which can be solved by using high impedance circuit to form the modified LC generator. The different values of discharge frequency can influence the discharge conditions significantly, thus, the average delay time of the modified LC generator is investigated comparing with the conventional LC generator.

In EDM, graphite is becoming a popular choice for tool electrode material due to its advantages in many aspects. However, the gap phenomena with graphite tool electrode are still rarely investigated. In this study, a high-speed camera was used to observe the gap phenomena in single pulse discharge experiments with graphite tool electrode. By virtue of a laser and flash lamp illuminations, the melt pool dynamics and material removal can be observed directly. The influence of polarity was investigated and the gap phenomena were compared with that with copper tool electrode.

In previous works, we have proposed an electrochemical machining (ECM) method using a kind of porous solid, which can be called Maifan stone ball (MFS-ball), as the electrolyte absorbing material. The experimental results show that the porous solid can control the distribution of electrolytes effectively during machining, and the electrochemical reactions only occur in the area covered by electrolytes. In addition, through follow-up experiments, we found out the influence of different experimental conditions on the experiment results. However, there are still some unclear points about the mechanism of this ECM method. Therefore, in this study, basing on experimental results and analysis, we tried to elucidate the machining mechanism of the ECM through electrolyte absorbed with the MFS-ball.

A glass press mold simulation code V-Glace is being developed based on static explicit finite element code V-Struct using degraded hexahedral mesh. Material parameters of glass required for this code is experimentarily analyzed such as creep law based on Norton law and friciton based on ring-compression method.

The safety performance of an automated driving vehicle must be validated comprehensively in the inspection, for innumerable traffic situations including situations with collision. Virtual testing on the chassis dynamo is proposed in the vehicle inspection to solve this matter. In this study, the image display method was examined on the VR testing system which was introduced in the previous study.

Wave-dissipating blocks are stacked on the breakwater as a protective structure to protect beaches, ports, and harbors from the erosion of waves. However, the motion and corrosion of sea waves also cause irreversible damage to the blocks, causing these structures to sink and even ablate. Therefore, regular repair work is required to maintain the height of the breakwater. To estimate the number of blocks required in the repair work, we first identified the existing block instances and estimated their 6D pose from 3D measured points captured from UAV and MBES. Then we first calculated the volume that needs to be filled over the existing blocks to reach the target height. Then, through the ratio of the volume to the one of a single block, the number of blocks for the work can be estimated within an acceptable error range.

Our ultrashort Kirkpatrick-Baez mirror with 2- and 8-mm-long mirrors has an extremely short focal length of 2 mm. While its working distance is also decreased, this design can benefit microscopic observation and X-ray focusing. Compared to the conventional X-ray mirrors whose radii of curvature typically exceed 10 m, these ultrashort mirrors have steeply curved figures with a radius of curvature of 150 mm. In this research, these ultrashort mirrors were fabricated by the differential deposition method. Their measurement employed a scanning white-light interferometer. Figure correction processes successfully produced a reflective surface with a figure error of 2.8 nm in peak-to-valley. This high-NA reflective optic was evaluated in focusing experiments at SPring-8, resulting in 50-nm soft-X-ray nanoprobes. To the best of our knowledge, these results demonstrate unprecedented soft-X-ray focusing that is diffraction-limited and achromatic.

We develop an alignment monitor which adopt a length measurement grid consisting of multiple measurement paths of absolute distance interferometers based on an optical frequency comb. Each interferometer refers a pulse interval compressed by an etalon. Here, we evaluate the pulse interval from the distance between the side peaks of the interference signals generated by the compressed pulse and the original optical frequency comb by referring the accurate and stable pulse repetition frequency of the original optical frequency comb with its relative expanded uncertainty of 1 ppm (k = 2).