Abstract: A radio wave absorbing panel is made up of a first insulating substrate and a second insulating substrate disposed in parallel a predetermined distance apart and a middle insulating substrate disposed between and parallel with the first and second substrates. The first and second substrates each have a conducting film coated over the entire surface of one side. On one side of the middle insulating substrate are coated multiple conducting films disposed in the form of stripes or a matrix. The width of each of the conducting films disposed in the form of stripes or a matrix is equal to or between 0.1 cm to 50 cm. By this means a thin radio wave absorbing panel having excellent radio wave absorption and transparency to light can be obtained.

Abstract: A radio wave absorbing panel is made up of a first insulating substrate and a second insulating substrate disposed in parallel a predetermined distance apart and a middle insulating substrate disposed between and parallel with the first and second substrates. The first and second substrates each have a conducting film coated over the entire surface of one side. On one side of the middle insulating substrate are coated multiple conducting films disposed in the form of stripes or a matrix. By this means a thin radio wave absorbing panel having excellent radio wave absorption and transparency to light can be obtained.

Abstract: A quality undisturbed sample of of cohesionless soil, in which the in-situ state of stress and strain is kept, can be obtained by in-situ freezing of the soil and subsequent removal of the frozen sample for testing. The in-situ horizontal stress in the cohesionless soil can be determined by the thawing the high quality undisturbed sample or, alternately, the frozen hole made in the frozen ground. A test apparatus and procedure for each of the two alternatives adjusts the pressure on the cylindrical sides of the sample or of the cored hole in the ground, to maintain the respective diameter as thawing occurs. The final pressure indicates the horizontal stress. In the case of testing the cylinder-shaped sample removed from the ground, it is loaded axially to reproduce the vertical load conditions at the level in the ground from where it was taken.