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scanned-pdf-ocr-to-wordHealth
Estimate glomerular filtration rate (eGFR) in children (1–18 y) with the Schwartz formula. 2009 Bedside version (recommended, IDMS-traceable creatinine): eGFR = 0.413 × Height(cm) / SCr(mg/dL). 1984 Original version (legacy, pre-IDMS assays): eGFR = 0.55 × Height(cm) / SCr(mg/dL). The coefficient dropped from 0.55 to 0.413 because IDMS-standardized assays return lower creatinine values. Returns a BSA-INDEXED eGFR in mL/min/1.73 m². Derived from Schwartz GJ et al., Am J Kidney Dis 2009 (0.413) and Pediatrics 1976 (0.55). Valid for pediatric stable renal function; use CKD-EPI/MDRD for adults, not for neonates/AKI. Not medical advice.
schwartz-pediatric-gfrMath & Numbers
Calculate the static safety factor n = σ_limit / σ_applied against yielding (σ_y) or ultimate tensile strength (σ_uts). Built-in typical strengths for carbon/alloy steel, aluminum, copper, austenitic stainless and titanium, plus a custom σ_limit option. Assessment: n<1 failure, 1≤n<1.5 marginal, n≥1.5 safe.
safety-factor-calculatorMath & Numbers
Split an air-conditioning load into sensible and latent components. Total cooling capacity Qt = ṁ_da·(h1 − h2); sensible capacity Qs = ṁ_da·cp_ma·(T1 − T2) with cp_ma ≈ 1.006 + 1.86·W [kJ/(kg da·K)]; latent capacity Ql = Qt − Qs; Sensible Heat Ratio SHR = Qs / Qt. Entering/leaving states are described by dry-bulb temperature T and humidity ratio W; enthalpy h = 1.006·T + W·(2501 + 1.86·T) [kJ/kg da]. Three modes: full air-state split (T1,W1)→(T2,W2), from Qt & Qs (solve SHR + Ql), or from Qt & SHR (solve Qs, Ql).
sensible-latent-heat-splitDevelopment
Audit SPDX 2.3 or CycloneDX 1.5 component licenses and emit SARIF with failing dependency paths
sbom-spdx-cyclonedx-license-policy-auditorMath & Numbers
Estimate the three-phase symmetric short-circuit current using the IEC 60909 far-from-generator method: I"_k = c·U_n/(√3·|Z|) and i_p = κ·√2·I"_k with κ = 1.02 + 0.98·e^(−3R/X). Source impedance is the series sum of transformer and line R/X.
short-circuit-current-calculatorMath & Numbers
Calculate the elastic section modulus W = I/y_max and associated geometric properties. Supports rectangle, solid circle, hollow tube, and I-beam; computes I, distance c, area A, and radius of gyration r. Units in mm.
section-modulus-calculatorMath & Numbers
Calculate the maximum shear stress τ_max = V·Q/(I·b) at the neutral axis of a beam section. Supports rectangle (1.5V/A), solid circle (4V/3A), hollow tube, and I-beam (exact V·Q_web/(I·tw)). Also returns the average shear stress V/A for comparison.
shear-stress-calculatorMath & Numbers
Calculate the critical (resonance) speed of a rotating shaft using the single-DOF rotor model. ω_n = √(k/m), n_cr = (60/2π)·√(k/m) rpm. Also returns the natural frequency f_n in Hz.
shaft-critical-speedMath & Numbers
Calculate the power transmitted by a rotating shaft. P = T·ω = 2π·n·T/60. Solve power from torque and speed, or torque from power and speed. Supports W/kW/hp.
shaft-power-calculatorFinance
Convert between hourly, monthly, and annual salary. Enter any one figure and get the other two, with customizable hours per week, weeks per year, and overtime multiplier. Shows paycheck estimates for weekly, biweekly, semimonthly, and monthly pay periods.
salary-converterFinance
Solve for the monthly contribution needed to reach a savings goal (with interest and compounding), or for the time required to reach the goal with a fixed monthly deposit. Optional inflation adjustment. Uses monthly compounding rollup.
savings-calculator