1,557 research outputs found
Study on Effects of the Density Current Generator by Experiment and Measurement
The density current generator (Manufacturer: Nakashima Propeller Co., Ltd., Patent owner: Hitachi Metals, Ltd.) is designed to generate vertical circulation over a wide water area harnessing the density current effect. We present some experimental results that we obtained using a float equipped with a GPS unit to study water flows generated by a density current generator unit set in S-Reservoir in Okayama Prefecture. We also present some measured results concerning the water temperature around the unit. We discuss its effects observing the experimental results and the measured results
Studies on the Determination of Non-Metallic Inclusions in Iron and Steel. I : Determination of Non-Metallic Inclusions in Plain Carbon Steel and Silicon Steel
Non-metallic inclusions in iron and steel are usually determined by hot nitric acid, electrolytic or chlorine methods. The present authors studied the adaptabilities of these three methods in the analyses of plain carbon steel and silicon steel, and obtained the following results : In plain carbon steel, these methods were easily carried out but hot nitric acid method gave a lower value for silica than other methods, and electrolytic method gave a higher value for ferrous oxide and manganese oxide than other methods. After all, chlorine method was most convenient and accurate. Hot nitric acid and electrolytic methods gave somewhat higher value for silica in silicon steel, but if more chlorine would be passed than in the usual case, chlorine method would give correct results
Low Frequency Hearing Thresholds in Pressure Field and in Free Field
Thresholds of hearing Were determined in pressure field at frequencies from 4 Hz to 125 Hz. At the frequencies 4–25 Hz hearing thresholds were found that are in the lower middle of the range already reported by other investigators. At frequencies from 25 Hz to 1 kHz thresholds have already been determined in free field by the same method and using the same subjects. The two investigations overlap at frequencies from 25 Hz to 125 Hz, and in this range the results were almost identical. The differences were below 1 dB, except at 63 Hz where the difference was 2.5 dB. None of the differences was significant in a t-test. </jats:p
The Loudness Level in the Free Field, and the Hearing Threshold in the Free Field and in the Pressure Field of Pure Tones at Frequencies below 1 kHz
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