Firearms identification requires professional knowledges and a lot of time cost. It is also necessary to quantitatively evaluate the performance of firearms identification schema. As the first step, the segments of the firing pin impression and primer cap in the cartridge cases may be assumed as one of the promising features for it. In this study, primer caps and firing pin impressions in the cartridge cases are detected by a proposed method utilizing the Hough transforms. From the depth images converted from a three dimensional profile of cartridge cases captured by a confocal microscope, through binarization and the Hough transform followed by the least squared fitting, the primer cap and the firing pin impression are detected by use of aggregation of multiple circles. The experiments using many profiles show the effectiveness of the proposed method, where the average deviation became less than the one by human operators.

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This paper addresses the auto-tuning of a feedforward controller for a linear stage. In our approach, particle swarm optimization (PSO), which is one of meta-heuristic algorithms, is employed. In PSO-based controller tuning, the initial placement and the number of particles are determined a priori. However, the initial placement of particles of the PSO was decided randomly or was not sufficiently discussed. Moreover, although the large number of particles is effective in terms of tuning accuracy, it causes the increase of tuning time. For these reasons, we focus on the setting of the initial placement and the number of particles in order to implement the PSO algorithm appropriate for the controller tuning of the linear stage. To shorten tuning time and improve tuning accuracy, firstly, the initial placement is determined by using the information on the nominal model of the linear stage. Then, since some parameters of the linear stage are known, the dimensionality of particles is reduced. Finally, in consideration of precision positioning, particles are divided into some groups. Furthermore, the number of particles is decided on the basis of the tuning time and the maximum number of iteration. The performance of our initial setting methods is evaluated by simulation and experiment.

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Bullet identification requires special skills and takes a long time. So novel method is expected to be developed for assisting this skillful and time-consuming work. The discrimination of two bullets needs similarity quantification of striated toolmarks most. But conventional method based on image correlation is not applicable because of lower striated toolmark similarity. In this paper, a new method is proposed to measure similarity correctly between striated toolmarks of bullets and makes it possible to extract inherent striated toolmarks of used gun. The effectiveness of the proposed method is confirmed through experiments.

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Confocal laser microscope (CLM) has been widely used in the fields of the non-contact surface topography, biomedical imaging, and other applications, because of two-dimensional (2D) or three-dimensional (3D) imaging capability with the confocal effect and the stray light elimination. Although the conventional CLM has acquired the 2D image by mechanical scanning of the focused beam spot, further reduction of image acquisition time and the robustness to various disturbances are strongly required. To this end, it is essential to omit mechanical scanning for the image acquisition. In this article, we developed the scan-less, full-field CLM by combination of the line-focused CLM with the wavelength/1D-space conversion. This combination enables us to form the 2D focal array of a 2D rainbow beam on a sample and to encode the 2D image information of a sample on the 2D rainbow beam. The image-encoded 2D rainbow beam was decoded as a spectral line image by a multi-channel spectrometer equipped with a CMOS camera without the need for the mechanical scanning. The confocal full-field image was acquired during 0.23 ms with the lateral resolution of 26.3μm and 4.9μm for the horizontal and vertical directions, respectively, and the depth resolution of 34.9μm. We further applied this scan-less, full-field CLM for biomedical imaging of a sliced specimen and non-contact surface topography of an industry products. These demonstrations highlight a high potential of the proposed scan-less, full-field CLM.

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Demands are increasing for highly-precise shape measurement of large curved surfaces such as lens and reflecting mirrors for telescopes. In this paper, a design concept of a new surface shape measuring method is proposed for the purposes using an improved sequential three-point method. The method has distinctive features described as follows. In three-point method, if a zero position error between sensors exists, a large quadratic error component is superimposed on measured shape profile. In the method proposed, the quadratic component is compensated using the difference between the inclination angles of sensor head at the starting and finishing points of shape measurement. When the specimen surface has large unevenness, the distance between surface and displacement sensors exceeds the working range of the sensors during measuring operation. Therefore, the distance from the specimen surface and the inclination angle of sensor head are adjusted so that the specimen surface always comes within the working range of all sensors. The surface shape profile of a curved surface the length of which is 700mm is evaluated by the experimental measuring equipment assembled based on the concept. The experimental result shows that the measuring error of the equipment is estimated to be about 0.40μm if the inclination angle of sensor head is measured properly.

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The polishing of cobalt alloy processed under ultraviolet (UV) irradiation was investigated to verify the effectiveness of ultraviolet-ray aided machining. Pure cobalt (Co) was immersed in aqueous solutions of TiO₂, cathilon dye, and TiO₂-cathilon due to clarify the chemical reaction. X-ray photoelectron spectroscopy (XPS) was used to quantitatively analyze the surfaces of the immersed Co samples. Inductively coupled plasma spectrometry (ICPS ) analyses were conducted to quantitatively determine the extent of oxidation/dissolution volume of Co, Cr and Mo. These analyses were used to estimate the compounds that are formed/removed by decomposition of cathilon in water during the polishing of Co-Cr-Mo alloy using TiO₂-, cathilon-, and TiO₂-cathilon slurries, all of which included Al₂O₃ powder. The XPS and ICPS measurements indicated that Co does not dissolve in an aqueous solution of TiO₂, whereas the aqueous solution of cathilon dissolves Co at a rate of approximately 10 mg/L. Although Co was dissolved in the aqueous solution of TiO₂-cathilon at a rate of approximately 70 mg/L, Cr and Mo were not dissolved in the same solution. UV irradiation has a more significant effect on Co-dissolution at lower concentrations of cathilon (0.5 and 1.0 wt%) than in an aqueous of 2.5 wt% cathilon, whereby oxide, nitrate, and hydroxides form on the Co. However, Cr and Mo form only their oxides. Chemical-mechanical polishing of the Co-Cr-Mo alloy using the TiO₂-cathilon slurry under UV irradiation resulted in surface roughness of Ra = 2.9 nm and Rz = 83 nm.

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This paper describes the removal of surface oxidation layer of oxygen free copper using Na₂SO₄ electrolyzed oxidizing water (It abbreviates as EO water). First, the etching characteristics of Na₂SO₄ EO water against the test pieces surface was clarified using H₂SO₄ solution and NaCl EO water for comparative immersion experiments. The results showed that as for etching efficiency on the surface of heating processing, Na₂SO₄ EO water is same as H₂SO₄ solution and NaCl EO water, and on the surface of non-heating, Na₂SO₄ EO water was superior compared with H₂SO₄ solution. Next, by the observation using SEM image, the influence of Na₂SO₄ EO water on the surface shape was clarified. The results indicated that when using Na₂SO₄ EO water and H₂SO₄ solution compared with NaCl EO water, the alien substances occurs in the surface of heating processing. Lastly, as for the test pieces after heating processing, it did the surface oxidation layer removal experiment by the immersion. The results showed that Na₂SO₄ EO water can remove the surface oxidation layer like the H₂SO₄ solution and NaCl EO water, and if using Na₂SO₄ EO water compared with NaCl EO water, there are few levels of contamination by chlorine.

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This study investigates the analysis of chemical mechanical polishing (CMP) mechanism by using the “mieruka” (visualization) technique of the contact interface between the wafer and the polishing pad when the suede type polishing pad was used in CMP. In particular, as mentioned previous our study, we clarified the linear velocity ratio, defined as the ratio of slurry flow velocity to pad linear velocity, has remarkably effect on the removal rate and contact interface behavior between the wafer and polishing pad. This paper scientifically investigates the relationship between the linear velocity ratio and contact interface behavior from the viewpoints of number of pores which is important property of the suede type polishing pad. As a result, the linear velocity ratio is effective parameter for making the optimized contact interface and stability of removal rate during CMP.

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