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When industrial robots transfer objects at high speeds, residual vibrations occur at the target positions. Recently, autonomous mobile robots such as AGV and AMR have become popular. However, the vibrations of the objects to be transported occur when the robot stops moving. Waiting until the residual vibration converges is necessary during the installation and assembly of transported objects. Thus, the overall work time increases even though the robots operate and move at a high speed. If the trajectory, which is the change in the position and attitude of the output point of a robot with time, can be adjusted such that the robot can move and operate within the same operation time by suppressing the residual vibration caused in transported objects, the work time can be significantly reduced. However, suppressing vibration is not easy because it usually requires solving complex equations of motion to consider the dynamics of robots. Therefore, in this study, based on the behavior of an object to be transported, which is measured by actually operating a robot, we propose a method for determining a trajectory that can suppress residual vibration using a heuristic algorithm without performing a kinetic analysis. The trajectories determined by this method reduced the settling time by approximately 90% with only a few dozen robot operations. The proposed method can be widely applied to commercial robots because appropriate trajectories are generated using a simple program that determines the variables used in the robot language without kinetic analysis. • We proposed the method for generating the trajectory of the robots using results measured in actual operation. • The trajectories suppress the residual vibration of the carried object by the heuristic algorithm. • The proposed method is widely applied to the commercial robot because the variables in the robot language are used. [ABSTRACT FROM AUTHOR]

Although skin permeability of an active ingredient can be severely affected by its ionization in a dose solution, most of the existing prediction models cannot predict such impacts. To provide reliable predictors, we curated a novel large dataset of in vitro human skin permeability coefficients for 322 entries comprising chemically diverse permeants whose ionization fractions can be calculated. Subsequently, we generated thousands of computational descriptors, including Log D (octanol–water distribution coefficient at a specific pH), and analyzed the dataset using nonlinear support vector regression (SVR) and Gaussian process regression (GPR) combined with greedy descriptor selection. The SVR model was slightly superior to the GPR model, with externally validated squared correlation coefficient, root mean square error, and mean absolute error values of 0.94, 0.29, and 0.21, respectively. These models indicate that Log D is effective for a comprehensive prediction of ionization effects on skin permeability. In addition, the proposed models satisfied the statistical criteria endorsed in recent model validation studies. These models can evaluate virtually generated compounds at any pH; therefore, they can be used for high-throughput evaluations of numerous active ingredients and optimization of their skin permeability with respect to permeant ionization. [ABSTRACT FROM AUTHOR]

The Crested Ibis, became extinct in the wild in Japan in 1981; however, a captive breeding facility was established on Sado Island, Niigata Prefecture in 1999 in the hope of conserving the species. Following successful breeding at the facility, a group of birds was released on Sado Island on 25th September 2008, with further reintroductions in subsequent years. Habitat restoration is also necessary to facilitate the re-introduction program of this endangered species. The aim of this study was to detect suitable nesting areas for the released ibises on Sado Island for subsequent nature restoration. Since little ibis nesting information was available for Sado Island, the nesting model was constructed from nesting information from China, from which results were extrapolated for Sado Island. Land usage was assessed using LANDSAT/ETM+ data for China and SPOT/HRG images for Sado Island. In this study, land-use information was used to define the environmental parameters related to nest site selection of the Crested Ibis. For the nesting model, a generalized linear mixed model, with seven environmental factors, was employed. The multi-spatial scale for Crested Ibis nesting was also analyzed. We took the spatial scale into consideration at intervals of 100 m from a buffer size of 100 m to 2500 m. Because nest site selection was influenced by the results of the previous year, nesting location data in 2005 and 2006 were distinguished and models built accordingly. Several important environmental factors were identified for nest site selection: the ratio of broadleaved deciduous forest to coniferous forest; the shape of the forest edge; and, the distance from rice fields and other wetlands. The model’s accuracy was verified using the Boyce index, and shows the validity of the model’s results. Suitable nesting areas for the Crested Ibis were found mainly on: the Kuninaka plain; the ridgeline between the Kuninaka plain and the Osado or Kosado mountain ranges; the area around Lake Kamo; and, the midwestern area of the Kosado region. Suitable nesting sites for the Crested Ibis were all found to be concentrated in what is known as Yatsuda , a traditional Japanese landscape structure providing a complex mosaic of forest and rice fields with complex ecotones. Eastern Kosado, the region that has been designated by the Ministry of the Environment as the conservation area for the reintroduced birds, was not judged to provide suitable nesting habitat for the Crested Ibis. Unfortunately, no evaluation of habitat suitability was made prior to the release of the first captive-bred Crested Ibis into the wild on Sado Island. Had an evaluation of habitat suitability been performed prior to release, more effective nature restoration could have been planned. [ABSTRACT FROM AUTHOR]

We conducted diatom analyses of a core from the Pleistocene marine sequence drilled at the Chiba Section, central Japan, to reveal detailed paleoceanographic variations across the Early–Middle Pleistocene boundary. Diatom valves are most abundant at 4.5 m below the Matuyama–Brunhes magnetic polarity boundary, followed by the second highest abundance at 18.6 m above the boundary, which is consistent with the sea-level changes inferred from planktonic δ 18 O data. The highest abundance is correlated with the Marine Isotope Stage (MIS) 19.3 sea-level highstand, and the second-highest with the MIS 19.1 highstand. The abundance of the extinct species Actinocyclus ingens is quite low around these sea-level highstands, whereas it is greatest at the core depth with the minimum diatom total valves, which is correlated to the MIS 19.2 lowstand. Cold-water diatom species that are characteristic of the Oyashio Current are dominant but coexist with warm-water species of the Kuroshio Current below a core depth just postdating MIS 19.2. Above this depth, warm diatom species of the Kuroshio Current become dominant. The change in dominant diatoms suggests that the Kuroshio Front shifted northward just after MIS 19.2 and remained in the northern area until at least early MIS 18. This shift caused a rapid increase in sea-surface temperature by 4–5 °C within a sediment thickness of 1.3 m (representing ∼300 years). [ABSTRACT FROM AUTHOR]

Abstract: Acetaldehyde azine (AcAz) underwent ‘crisscross’ addition with two equivalents of phenyl isocyanate to form a one-to-two adduct in a moderate yield (63.0%). Using crisscross addition of AcAz, polymeric products were obtained from AcAz and 1,4-phenylene diisocyanate in a high yield (>80%). The polymer obtained was soluble in 1,1,1,3,3,3-hexafluoro-2-propanol, and insoluble in many organic solvents, including n-hexane, benzene, toluene, chloroform, diethyl ether, tetrahydrofuran, acetone, ethanol, methanol, dimethyl sulfoxide, and N,N-dimethylformamide. The structure of the polymer obtained was characterized by IR and 1H NMR spectroscopies. The thermal behavior of the polymer was also investigated by thermogravimetric analysis. [Copyright &y& Elsevier]