25. Broncode trillingstool Archipunt.sql.txt

-- Empirical Ground Motion Prediction Method for small earthquakes - Julian Bommer etal 2019.pdf

DROP FUNCTION IF EXISTS lookup.PGV_v4emp_2019_in_mmps(numeric,numeric,numeric,numeric) CASCADE;
CREATE OR REPLACE FUNCTION lookup.PGV_v4emp_2019_in_mmps(magnitude numeric, diepte_km numeric, hor_afstand_km numeric, N numeric) RETURNS numeric
    AS $$
DECLARE
	sigma CONSTANT numeric :=  0.5777;
	c1    CONSTANT numeric := -5.0006;  --Table 3.1; column PGVMaxRot, row C₁    [UPDATED 2019]
	c2    CONSTANT numeric :=  2.2770;  --Table 3.1; column PGVMaxRot, row C1₂   [UPDATED 2019]
	c4    CONSTANT numeric := -1.9446;  --Table 3.1; column PGVMaxRot, row C1₃   [UPDATED 2019]
	c4a   CONSTANT numeric := -1.2077;   --Table 3.1; column PGVMaxRot, row C1₄ᵃ [UPDATED 2019]
	c4b   CONSTANT numeric := -1.6533;  --Table 3.1; column PGVMaxRot, row C1₄ᵇ  [UPDATED 2019]
	Repi         numeric;             --
	R            numeric;             --
	g_R          numeric;             --
	ln_PGV       numeric;             --In cm/s
BEGIN
	Repi := hor_afstand_km;  -- Formula takes distance between epi-centre and address, NOT hypo-centre
	R := sqrt( Repi^2 + exp(0.4233*magnitude - 0.6083)^2 );         --(3.2)
	CASE
		WHEN R <= 6.32 THEN                                           --(3.3a)
			g_R := c4*ln(R);                                            --(3.3a)
		WHEN R <= 11.62 THEN                                          --(3.3a)+(3.3b)
			g_R := c4*ln(6.32) + c4a*ln(R/6.32);                        --(3.3a)+(3.3b)
		ELSE                                                          --(3.3a)+(3.3b)+(3.3c)
			g_R := c4*ln(6.32) + c4a*ln(11.62/6.32) + c4b*ln(R/11.62);  --(3.3a)+(3.3b)+(3.3c)
	END CASE;
	ln_PGV := c1 + c2*magnitude + g_R + sigma*N;                    --(3.1)
	RETURN exp(ln_PGV)*10;                                          -- Converteren naar PGV in mm/s
END
$$
    LANGUAGE plpgsql
    IMMUTABLE
    RETURNS NULL ON NULL INPUT
;