A Short Essay on Ancient Raw Metal for Iron-making and the Refining Method in the Hiroshima Prefecture

Smelting slag with a high level of manganese oxide (MnO) has been confirmed in the Kanakuro-tani site in Sera-chō, Sera-gun, Hiroshima Prefecture. It is observed that components, such as FeO-SiO2-MaO, of these slags are concentrated in a low melting zone (lower than 1300°C) when plotted on a phase diagram. MnO seems to have played the role of fluxing material to stabilize the operation of iron-making furnaces. The two mineral specimens were MnO minerals without any iron content. Therefore it is presumed that they were discarded during the concentration process as they did not have any iron content. Four iron slag specimens were investigated concerning their content. One of them had 2% MnO and in three of them, there was less than 1% MnO. Besides, all of them contained 1~3% Titania. These results indicate that both iron ore and iron sand were used as iron-making materials at the Kanakuro-tani site

Stein Variational Guided Model Predictive Path Integral Control: Proposal and Experiments with Fast Maneuvering Vehicles

This paper presents a novel Stochastic Optimal Control (SOC) method based on Model Predictive Path Integral control (MPPI), named Stein Variational Guided MPPI (SVG-MPPI), designed to handle rapidly shifting multimodal optimal action distributions. While MPPI can find a Gaussian-approximated optimal action distribution in closed form, i.e., without iterative solution updates, it struggles with multimodality of the optimal distributions, such as those involving non-convex constraints for obstacle avoidance. This is due to the less representative nature of the Gaussian. To overcome this limitation, our method aims to identify a target mode of the optimal distribution and guide the solution to converge to fit it. In the proposed method, the target mode is roughly estimated using a modified Stein Variational Gradient Descent (SVGD) method and embedded into the MPPI algorithm to find a closed-form "mode-seeking" solution that covers only the target mode, thus preserving the fast convergence property of MPPI. Our simulation and real-world experimental results demonstrate that SVG-MPPI outperforms both the original MPPI and other state-of-the-art sampling-based SOC algorithms in terms of path-tracking and obstacle-avoidance capabilities. Source code: https://github.com/kohonda/proj-svg_mppiComment: 7 pages, 5 figure

Skeletal oxygen and carbon isotope compositions of Acropora coral primary polyps experimentally cultured at different temperatures

We investigated temperature and growth‐rate dependency of skeletal oxygen and carbon isotopes in primary polyps of Acropora digitifera (Scleractinia: Acroporidae) by culturing them at 20, 23, 27, or 31°C. Calcification was most rapid at 27 and 31°C. We obtained a δ18O‐temperature relationship (−0.18‰ °C−1) consistent with reported ranges for Porites, indicating that juvenile Acropora polyps can be used for temperature reconstruction. A growth‐rate dependency of skeletal isotopes was detected in the experimental polyps cultured at lower water temperatures, when the skeletal growth rate of these polyps was also low. The estimated upper calcification flux limit for a kinetic isotope effect to be observed in the δ18O‐growth rate relationship (∼0.4–0.7 g CaCO3 cm−2 yr−1) was similar to the calcification flux in Porites corresponding to a linear extension rate of 5 mm yr−1, the maximum rate at which the kinetic isotope effect is evident. This result suggests that the calcification flux can be used as a measure of growth rate‐related isotope fractionation, that is, the kinetic isotope effect, in corals of different genera and at different growth stages

Thermal dependency of shell growth, microstructure, and stable isotopes in laboratory‐reared Scapharca broughtonii (Mollusca: Bivalvia)

We experimentally examined the growth, microstructure, and chemistry of shells of the bloody clam, Scapharca broughtonii (Mollusca: Bivalvia), reared at five temperatures (13, 17, 21, 25, and 29°C) with a constant pCO2 condition (∼450 μatm). In this species, the exterior side of the shell is characterized by a composite prismatic structure; on the interior side, it has a crossed lamellar structure on the interior surface. We previously found a negative correlation between temperature and the relative thickness of the composite prismatic structure in field‐collected specimens. In the reared specimens, the relationship curve between temperature and the growth increment of the composite prismatic structure was humped shaped, with a maximum at 17°C, which was compatible with the results obtained in the field‐collected specimens. In contrast, the thickness of the crossed lamellar structure was constant over the temperature range tested. These results suggest that the composite prismatic structure principally accounts for the thermal dependency of shell growth, and this inference was supported by the finding that shell growth rates were significantly correlated with the thickness of the composite prismatic structure. We also found a negative relationship between the rearing temperature and δ18O of the shell margin, in close quantitative agreement with previous reports. The findings presented here will contribute to the improved age determination of fossil and recent clams based on seasonal microstructural records

The infrared imaging spectrograph (IRIS) for TMT: status report for IRIS imager

The current status of IRIS imager at NAOJ is reported. IRIS (Infrared Imaging Spectrograph) is a first light instrument of TMT (Thirty Meter Telescope). IRIS has just passed the preliminary design review and moved forward to the final design phase. In this paper, optical and mechanical design of IRIS imager and prototyping activities conducted during the preliminary design phase are summarized

Establishment of a reborn MMV-microarray technology: realization of microbiome analysis and other hitherto inaccessible technologies

BACKGROUND: With the accelerating development of bioscience, the problem of research cost has become important. We previously devised and developed a novel concept microarray with manageable volumes (MMV) using a soft gel. It demonstrated the great potential of the MMV technology with the examples of 1024-parallel-cell culture and PCR experiments. However, its full potential failed to be expressed, owing to the nature of the material used for the MMV chip. RESULTS: In the present study, by developing plastic-based MMVs and associated technologies, we introduced novel technologies such as C2D2P (in which the cells in each well are converted from DNA to protein in 1024-parallel), NGS-non-dependent microbiome analysis, and other powerful applications. CONCLUSIONS: The reborn MMV-microarray technology has proven to be highly efficient and cost-effective (with approximately 100-fold cost reduction) and enables us to realize hitherto unattainable technologies

Development Automobile Engine Hood Latch

V diplomové práci se zabývá konstrukčním návrhem automobilového zámku, který má hlavní komponenty v „plastovém“ provedení (rohatka, západka, tělesa). Tyto plastové díly jsem vhodně navrhl a optimalizoval na požadované zatížení. Zároveň srovnávám plastový zámek a ocelový zámek přední kapoty, srovnávám jak cenu zámků, tak hmotnost a zatížení zámků. V krátkosti porovnávám automobilové zámky přední kapoty v současném automobilovém průmyslu. Také se zabývám etapou výroby prototypového vzorku v současnosti.The diploma thesis deals with the design of the car lock, which main components such as claw, pawl and housing are made of plastic. My main goal was to optimized these plastic parts for a certain amount of power. The following part shows a comparison of plastic lock and the steel lock of front bonnet. The following part shows a comparison of the plastic lock and the steel lock of the front bonnet. The comparison is made in terms of the price, weight and load of the locks. The diploma thesis also briefly deals with the comparison of car locks of car locks of front bonnets in the current automotive industry and the stage of prototype sample production nowadays.340 - Katedra výrobních strojů a konstruovánívelmi dobř

Thermal dependency of shell growth, microstructure, and stable isotopes in laboratory-reared Scapharca broughtonii (Mollusca: Bivalvia)

金沢大学国際基幹教育院 GS教育系We experimentally examined the growth, microstructure, and chemistry of shells of the bloody clam, Scapharca broughtonii (Mollusca: Bivalvia), reared at five temperatures (13, 17, 21, 25, and 29°C) with a constant pCO2 condition (∼450 μatm). In this species, the exterior side of the shell is characterized by a composite prismatic structure; on the interior side, it has a crossed lamellar structure on the interior surface. We previously found a negative correlation between temperature and the relative thickness of the composite prismatic structure in field-collected specimens. In the reared specimens, the relationship curve between temperature and the growth increment of the composite prismatic structure was humped shaped, with a maximum at 17°C, which was compatible with the results obtained in the field-collected specimens. In contrast, the thickness of the crossed lamellar structure was constant over the temperature range tested. These results suggest that the composite prismatic structure principally accounts for the thermal dependency of shell growth, and this inference was supported by the finding that shell growth rates were significantly correlated with the thickness of the composite prismatic structure. We also found a negative relationship between the rearing temperature and δ18O of the shell margin, in close quantitative agreement with previous reports. The findings presented here will contribute to the improved age determination of fossil and recent clams based on seasonal microstructural records. Key Points: Thermal plasticity of shell microstructural formation was examined Relative volume of composite prismatic structure was greatest at cooler temperature Growth rates were correlated with volume of composite prismatic structure © 2015. American Geophysical Union. All Rights Reserved