Health

Estimate expected adult vital capacity with the Baldwin equations ((27.63 − 0.112×age)×height for males, (21.78 − 0.101×age)×height for females) and optionally grade a measured VC as % predicted. Not medical advice.

Health

Adjust warfarin maintenance dose from the current INR using the standard nomogram for a target INR of 2.0–3.0. No-bleed ladder: INR<1.5 → +10–20% weekly dose; 1.5–1.9 → +5–15%; 2.0–3.0 → no change; 3.1–3.5 → −5–15%; 3.6–4.0 → −10–20%; 4.1–4.4 → hold 0–1 dose, ~−20%; 4.5–10 → hold + oral vitamin K₁ 1–2.5 mg; >10 → hold + oral vitamin K₁ 2.5–5 mg. Serious/life-threatening bleed at any INR → hold warfarin, vitamin K₁ 5–10 mg IV (slow, 20–30 min) + 4-factor PCC (FFP if unavailable). Optional current weekly dose computes the concrete new weekly and daily dose. Derived from the 9th-edition ACCP Guidelines (Holbrook et al., Chest 2012) and the UW Anticoagulation Clinic nomogram. Valid for adult maintenance therapy at steady state; not for initial induction, DOAC/heparin overlap, or perioperative bridging. Not medical advice.

Health

Calculate the apparent volume of distribution Vd in two modes. (A) One-compartment IV bolus: Vd = Dose / C0 (C0 = concentration extrapolated to t=0). (B) From clearance and half-life (linear kinetics): Vd = CL · t½ / 0.693. Vd is an APPARENT (theoretical) volume, not an anatomical one — highly tissue-bound drugs (digoxin ≈ 7 L/kg, amiodarone ≈ 66 L/kg) can exceed total body water, while highly plasma-protein-bound drugs (warfarin ≈ 0.14 L/kg) fall far below it. Optional body-weight input converts the result to L/kg. Note: Vd = Dose/C0 gives Vc (initial); Vss (steady state) and Vz (terminal) differ for multi-compartment models, and oral dosing returns Vd/F. Not medical advice.

Math & Numbers

Convert illuminance between lux (lx = lm/m², SI base), kilolux (1 = 1000 lx), footcandle (1 = 10.7639104 lx), phot (1 = 10000 lx), and nox (1 = 0.001 lx). Converts via lux to the target unit and lists the equivalent value in all five units for reference. Reference values: full moon ≈ 0.25, office lighting ≈ 300–500, overcast day ≈ 1000, direct sunlight ≈ 100000 lux.

PDF Tools

Permanently remove PDF text and hidden page objects by rebuilding an image-only PDF.

Math & Numbers

Convert thermal resistance between K/W (kelvin per watt, SI base), °C/W (1 = 1 K/W, since Δ1 K = Δ1 °C exactly), and °F·h/BTU International Table (1 = 1.8956342 K/W). Converts via K/W to the target unit and lists the equivalent value in all three units for reference. Reference values: CPU heatsink ≈ 0.1–0.3, LED thermal path ≈ 5–20, natural convection ≈ 1 K/W.

Math & Numbers

Convert thermal conductivity between W/(m·K) (watt per metre-kelvin, SI base, = W/(m·°C)), kcal/(m·h·°C) (1 = 1.1627778 W/(m·K)), and BTU/(hr·ft·°F) (1 = 1.7307347 W/(m·K)). Converts via W/(m·K) to the target unit and also lists the equivalent value in all three units for reference. Reference values: copper ≈ 401, aluminum ≈ 237, steel ≈ 50, water ≈ 0.6, air ≈ 0.026, insulation foam ≈ 0.03 W/(m·K).

Math & Numbers

Convert between Brinell (HB), Vickers (HV), and Rockwell (HRC / HRB) hardness via ASTM E140 tabulated data with linear interpolation. Three material classes: carbon/alloy steel (HV 100–960), austenitic stainless (HV 100–600), and cartridge brass (HV 40–200). Any input scale produces all the others; a scale that does not apply in the current hardness band returns 'out of range'. Indicative only — not for acceptance testing per ASTM E140.

Math & Numbers

Linear and volumetric thermal expansion of an isotropic material. Linear: ΔL = α·L₀·ΔT, L₁ = L₀·(1+α·ΔT). Volumetric: ΔV = 3α·V₀·ΔT (β = 3α for isotropic solids). Built-in typical α for carbon/alloy steel, aluminum, copper, austenitic stainless, titanium and glass, plus custom. ΔT in K or °C, length in mm, volume in mm³.

Math & Numbers

Thermal stress in a fully constrained member under a uniform temperature change: σ_th = E·α·ΔT. Built-in typical Young's modulus E and expansion coefficient α for carbon/alloy steel, aluminum, copper, austenitic stainless and titanium, plus custom values. ΔT in K or °C (same magnitude), result in MPa. Heating (ΔT>0) → compressive stress in the member.

Math & Numbers

Compute the full set of moist-air (psychrometric) state properties from dry-bulb temperature plus one humidity input (relative humidity φ, wet-bulb temperature, dew-point temperature, or humidity ratio W). Returns humidity ratio W (kg/kg and g/kg), relative humidity φ (%), dew-point, wet-bulb, enthalpy h (kJ/kg dry air), specific volume v (m³/kg dry air), partial vapour pressure P_w, and saturation pressure P_ws. Uses the Magnus saturation-pressure fit; wet-bulb is solved iteratively from the thermodynamic psychrometric equation. Default standard atmosphere 101.325 kPa (adjustable). Temperature in °C/K/°F; all reported temperatures are in °C.

Math & Numbers

Compute the thermal comfort indices PMV (Predicted Mean Vote, −3 cold..+3 hot) and PPD (Predicted Percentage Dissatisfied, %) per ISO 7730 / ASHRAE 55, using the Fanger equations. Inputs: air temperature Ta, mean radiant temperature Tr, relative air velocity v_ar, relative humidity φ, metabolic rate M (met; 1 met = 58.2 W/m²), clothing insulation Icl (clo; 1 clo = 0.155 m²·K/W), and external work W (defaults to 0). The clothing surface temperature Tcl is solved iteratively. Returns a 7-level ASHRAE sensation label.