We also analyze the effect of refraction in underwater application of vision measurement system, and show the modified expressions. Analyze how to calibrate an underwater camera in the air.

Test section was made of quartz glass tube with a refractive index of 1.458,meanwhile,a mixture of 54% benzyl alcohol and 46% ethyl alcohol with the same refractive index as that of quartz glass was chosen as working fluid,so that the effect of refraction on the tube wall was successfully eliminated.

In this paper the effect of refraction index from 1. 90 to 2. 00 on reflection of return reflecting fabric is studied from two aspects of the direction and the intensity of return reflected light.

The effect of refraction on the oblique angles was studied.

Effect of refraction on propagation of a wave beam in a turbulent medium (atmosphere)

Effect of refraction on power deposition profiles during electron cyclotron wave injection in a toroidal fusion plasma

The effect of refraction in this system is not considered.

For four years(1951—54)time determination data,after allowed for personal equation and referred to the mean observatory which is formed by the International Time Office(B.I.H.),seasonal fluctuation with amp- litude equals to 25 ms is found.That is,the clock corrections observed at Zi-Ka-Wei Observatory seem larger in May while smaller in February and July as compered with their annual mean. The Δ(α_α) type error of the fundamental catalogue(FK_3)contributes to the seasonal fluctuation with an amount of 6ms only....

For four years(1951—54)time determination data,after allowed for personal equation and referred to the mean observatory which is formed by the International Time Office(B.I.H.),seasonal fluctuation with amp- litude equals to 25 ms is found.That is,the clock corrections observed at Zi-Ka-Wei Observatory seem larger in May while smaller in February and July as compered with their annual mean. The Δ(α_α) type error of the fundamental catalogue(FK_3)contributes to the seasonal fluctuation with an amount of 6ms only. Inclination of atmospheric equi-density surface in pre-earth layer which is calculated with air pressure and temperature data taken from Shanghai and Lig-Yang(180km west of Shanghai)shows annual variation of 2′.5, thus the effect of refraction anomaly corresponding to the inclination calcu- lated is practically null. Besides,room refraction is also harmful.By the air temperature data taken from the east and west wall inside the observing room,the effect of room refraction thus estimated may become 8 ms in summer and turn to zero in winter. However,after draw out the influence of Δ(α_α) type error and room re- fraction,the seasonal fluctuation still appear.It is thought that thermal deformation of the transit instrument may be account for,as the diurnal change of air temperature and the temperature drop at night both signi- ficantly correlate to the seasonal fluctuation of time observation.

The paper first analyzes the effect of refraction on triangle closure in extensive tri angulation chain. Then in considering the effects of random error, refraction and error of centring correction, the formula for estimating the correlation coefficient ρ_ between two adjacent triangle closures is derived, and the relation between the ratio K_f of the random m.s. e.to m_f, which is the angle m. s. e. given by Ferrero criterion, and the estimation of σ_, and the formula to estimate the m.s.e....

The paper first analyzes the effect of refraction on triangle closure in extensive tri angulation chain. Then in considering the effects of random error, refraction and error of centring correction, the formula for estimating the correlation coefficient ρ_ between two adjacent triangle closures is derived, and the relation between the ratio K_f of the random m.s. e.to m_f, which is the angle m. s. e. given by Ferrero criterion, and the estimation of σ_, and the formula to estimate the m.s.e. of observation of any certain angle in a chain are further deduced. The latter two formulas are and the approximate formula for estimating the variance of any given angle α where m_ is the random m.s.e of the observed angle awithout refraction effects,and s_0, D_s the mean value taken over all sides in the chain and the variance to the mean. Applying the above formulas to the Chinese first order triangulation chain,the result is that K_f~2≈0.61=0.61, i. e., the effect of random errors is 61% in m_f~2, and that of nonuniform refraction fields is about 39% in the chain. In addition, it may be considered that σ_△=-0.13 and the tendency for large angles to be less accurate in the chain both are caused by the effect of non-uniform refraction fields.

In this paper the effect of refraction index from 1. 90 to 2. 00 on reflection of return reflecting fabric is studied from two aspects of the direction and the intensity of return reflected light.