A model fluidics (54 mm × 28 mm) was studied for its applicability as a steering unit to a sprinkler boat. A water jet was deflected at an inlet pressure of more than 2.0 kPa, where the velocity of the water jet is was more than 2.2 m/s. The bow thrust of the fluidics when attached onto the model boat (36 cm × 16 cm) was 0.02 to 0.12 N and quadratic to the increasing velocity of the water jet ranging between 2.2 to 5.4 m/s. Investigation of boat turning revealed that the turning trajectory transcribed a steady turning circle with a turning radius of 0.6 to 1.1 m at a peripheral velocity ranging between 0.15 and 0.28 m/s.

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A study was conducted to investigate the best wavelengths for fluorescence excitation and the resulting fluorescence wavelengths in the range of 300-700 nm with citrus peels taken from 15 varieties, which are concerned with detection of surface defects of citrus fruits. Characteristics of UV absorbance, excitation and fluorescence spectra were observed by variety, and principle components analysis (PCA) and discriminate analysis (DA) were used to categorize the citrus varieties by fluorescence intensity levels in order to give some tips for optimizing the fluorescence imaging based machine vision system. The observed proper excitation wavelength for best fluorescence emmision and resulting peak fluorescence wavelength varied variety to variety and ranged from 350 to 380 nm and 490 to 540 nm respectively. The selected varieties of citrus were categorized successfully into four groups of known fluorescence level, namely strong, medium, weak and no fluorescence groups.

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Bent cabbage seedlings unfit for transplanters and they are often grown in culture. The reason for this bending of the seedlings has not yet been clarified. We focused on the hypocotyl during the seedling stage because the hypocotyl being relatively soft may be bent due to the seedling’s own weight. We constructed a bending simulation model, which expresses bending as a function of seedling weight based on the large-deflection curve theory with measurements of morphological and mechanical parameters. Simulation results demonstrated that the cause of seedling bending is the effect of the first true leaf. In the middle of the seedling stage, the hypocotyl showed maximum bending.

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Merapi is categorized as the most active volcano in Indonesia and most important place of open green space in Yogyakarta, Indonesia. Merapi had erupted from September to October 2010 and destroyed many open green spaces. One of the potential solutions to increase percentage of open green space is the application of greening material in eco-agro-tourism program in Merapi Disaster Prone Area. Greening material is a plant panel consisting of plant and hydroponics media; suitable to be attached in the surroundings of a building. Sphagnum Moss (Sphagnum sp) which is a local biodiversity was used and evaluated as a greening material. The design was developed using Kansei Engineering. Four prototypes of the Sphagnum Moss as greening material were generated as rooftop, canopy, pot and portable garden.

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The automation of agricultural work is expected to solve several of Japan’s agriculture problems and help farmers. It has now become necessary to maintain the sustainability of national agricultural production. Thus, we have been trying to develop a robotic combine harvester. While attempts have been made to develop robotic combine harvester and a few prototypes can run and automatically harvest rice and wheat, the unloading task, in which grains are unloaded through the harvester’s auger into a grain container on a truck, has not yet been automated. This paper presents a method that uses machine vision to position the harvester’s spout at an appropriate point over the grain container on a truck. Experimental results show that this method has sufficient accuracy.

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The feasibility of using attenuated total reflectance-terahertz (ATR-THz) spectroscopy for quantification of L-ascorbic acid (L-AA) in aqueous solutions was investigated. The spectra of 55 samples of L-AA solution ranging in concentration from 0-21% were acquired using Terahertz-based Fourier transform infrared (THz-FTIR) spectrometer. Spectral absorbance in the range 20 to 400 cm^-1 was used in this analysis. Full spectrum partial least squares (FS-PLS) regression was used to develop and validate the calibration model for determination of L-AA. The result showed that using the pre-processing of Savitzky-Golay first derivative spectra, prediction resulted in the lowest root mean square error of prediction (RMSEP) = 2.791%. A ratio of standard deviation to prediction error (RPD) value of 4.48 was obtained.

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