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Volume 35 (1973)
- Issue 4 Pages 169-
- Issue 3 Pages 117-
- Issue 2 Pages 59-
- Issue 1 Pages 1-
Volume 35, Issue 4
Displaying 1-4 of 4 articles from this issue
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Akio TOUKAIRIN1973 Volume 35 Issue 4 Pages 169-172
Published: December 31, 1973
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSHot-wire ice thickness meter is made very easily by using a nichrome wire (diameter 0.7mm, specific resistance 0.03Ω/cm) and an alkaline dry-battery (6-15V, 3-4A).
In this paper, Fig. 1 shows the hot-wire ice thickness meter. Two examples of the measurements on the relation between ice growth and freezing index are given in Fig. 2. The hot-wire ice thickness meter and all implements used for setting and measuring are shown in Photo 1.View full abstractDownload PDF (2728K) -
Akio TOUKAIRIN1973 Volume 35 Issue 4 Pages 173-179
Published: December 31, 1973
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThe radial ice surface of Lake Harutori was not formed by wind or inflow of water of melting snow and ice. It was found to have grown as the channel of relatively warm lake water gushing through the snow accumulated on the lake surface.View full abstractDownload PDF (12778K) -
Masayuki INOUE, Masuyoshi MATSUDA1973 Volume 35 Issue 4 Pages 180-191
Published: December 31, 1973
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThe Yukikabe perennial snow patch with a volume of 2×105 m3 at most is located at lat. 43.6°N and long. 142.9°E, lying on the east slope, 1720 to 1760 meters in elevation, at the Takanegahara Plateau in the Daisetsu Mountains. Twenty-five longitudinal cross sections of Yukikabe were drawn from measurements which were carried out during the summer only from 1964 to 1972. If one assumes that the density of Yukikabe snow patch is constant, the mass balance will be expressed in terms of the thickness. As Yukikabe is divided by different mass balance scheme into upper and lower parts with an angle of about 15° and 40° respectively, one point on both parts was adopted as the representative station in considering the mass balance. Accumulation and ablation were deduced from the changes in the thickness of snow patch at these two representative points. About 20 meters of summer ablation was observed at both parts. They can estimate the minimum thickness at the end of summer season from limited data of thickness, for there is a good correlation between the rate of ablation and the accumulated air temperatures (degree·days) at Asahikawa Weather Station about 100 km apart, assuming a lapse rate of 0.6°C/100m. The estimated net balances are verified by comparison with the results obtained on the surface of Yukikabe in late summer. The thickness of the upper part remains 26 meters during the winter season, while the thickness of the lower part varies from 15 to 30 meters depending on the amount of drifting snow from the Takanegahara Plateau. The square of the maximum thickness of the lower part is found to be closely related to the sum of products, P times V3, where P (mm) is the mean precipitation at four meteorological stations near the Daisetsu Mountains and V (m/s) is the daily mean wind velocity at 800 mb at three stations during the winter. Thus, the net balance of Yukikabe can be approximated by only the meteorological data at observatories.View full abstractDownload PDF (1935K) -
Michiya SUZUKI, Mitsuhiro ONO, Yasuo NOMURA1973 Volume 35 Issue 4 Pages 192-200
Published: December 31, 1973
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThe quasi millimeter wave performance suffers degradation under rain, due to the high loss tangent of water in the quasi millimeter wave region. This effect cannot be theoretically estimated due to the complex nature of water flow on the radome surface. The above special effect is observed also in the case of snow-covered surface of the dome.
In order to ascertain the above-mentioned effect, some model tests were performed. The main results are summarized as follows :
(1) Laboratory tests on the effects of water accretion on the radome surface
The surface area of the radome used in this experiment is 50cm×50cm, and the frequency used is 24 GHz. It is found that attenuation factor vs. thickness of water film becomes about 18dB/mm. And attenuation factor vs. area percentage of stringy flow of running water is correlative.
(2) Field tests on the effects of snow accretion on the practical radome surface
The aperture size of the practical radome used in this experiment is 3.3 meters, and this radome is made of dielectric plates (laminated polyester resin reinforced with glass fiber).
Diurnal variations of snow accretion on the above radome were observed in the winter of 1973. The maximum thickness of accreted snow layer was about 60 cm. The condition of snow accretion varied quickly over a wide range chiefly with air temperature, especially above 0°C, and with weather conditions (sunny or shaded sides of the radome).View full abstractDownload PDF (10649K)
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