🛡️ Ọkọnọ nchebe na njikere Ụdị dị ndụ

Ntọala — ụdị dị n'azụ ọnụọgụ

Mmekọrịta ọ bụla simulator na-eji, na isi mmalite ya. Ihe na-agbanwe agbanwe akara dị ka echiche bụ nhazi ngosi.

Operational availability: oge ka sistemụ dị njikere, gụnyere igbu oge nke ọkọnọ.

Ao = uptime / (uptime + downtime) ≈ MTBF / (MTBF + MTTR + MLDT)[1][2]

Platform na-ada n'ụzọ enweghị usoro site n'oge ọdịda exponential mgbe ha na-arụ ọrụ.

P(fail during h operating hours) = 1 − e^(−h/MTBF), MTBF = 40 h[2]Echiche: MTBF, ohere akụkụ, ọnụọgụ ojiji na okporo ụzọ bụ ọnụọgụ atụmatụ n'ozuzu, ọ bụghị data banyere sistemụ ọ bụla n'ezie.

Usoro Palm: na ọkọnọ otu n'ọnọdụ otu, akụkụ ndị dị n'usoro na-agbaso nkesa Poisson.

pipeline ~ Poisson(mean = demand rate × lead time); backorders = (pipeline − S)⁺[4][3]

Ndozi na-eche n'ahịrị nke ọnụọgụ ìgwè kwụsiri ike na-ejere ozi.

c teams serve the maintenance queue (M/M/c); site teams + fleet teams = 8[9]Echiche: MTBF, ohere akụkụ, ọnụọgụ ojiji na okporo ụzọ bụ ọnụọgụ atụmatụ n'ozuzu, ọ bụghị data banyere sistemụ ọ bụla n'ezie.

Days of supply: ogologo oge ụlọ nchekwa ga-adịru na ojiji nke taa.

DOS = stock / daily consumption[10]Days of supply bụ usoro atụmatụ ejiri na ozizi nkwado; oke ahụ n'onwe ya bụ mgbako dị mfe.

Mgbochi Erlang B, na ịgbasa ya kpọmkwem mgbe a debere ọwa maka okporo ụzọ mbụ.

B(0)=1, B(k) = A·B(k−1) / (k + A·B(k−1)); with reservation r: exact birth–death chain[5][6]

Nha radar: oke nchọpụta na-eto n'ime mgbọrọgwụ nke anọ nke ike e zigara.

R ∝ P^(1/4) ⇒ πR² ∝ √P[7]

Ihe atụmatụ ndị ọzọ ejiri na ụdị a.

MTBF 40 operating h · part needed 40 % · repair Exp(6 h) · sites MTBF 300 h, repair Exp(8 h) · convoy 200 u · burn 1 u per operating h + 0.5 u/h per site at full power · relay +4 channels after 3 h · priority shipment: ≤ 4 open orders, lands within 24 h, one in flight at a time · ≥2 channels always open to routine trafficEchiche: MTBF, ohere akụkụ, ọnụọgụ ojiji na okporo ụzọ bụ ọnụọgụ atụmatụ n'ozuzu, ọ bụghị data banyere sistemụ ọ bụla n'ezie.

Ụdị mkpuchi Boolean: ohere na otu ebe ka sensọ disc opekata mpe otu hụrụ ya.

coverage = 1 − exp(−Σ πR_i² / A)[8]Echiche: MTBF, ohere akụkụ, ọnụọgụ ojiji na okporo ụzọ bụ ọnụọgụ atụmatụ n'ozuzu, ọ bụghị data banyere sistemụ ọ bụla n'ezie.

Enweghị usoro: ihe mmepụta mulberry32 nwere mkpụrụ; nkesa ejiri — uniform, exponential (inverse CDF), normal (Box–Muller), Poisson (Knuth). A na-egosi mkpụrụ ma nwee ike ikekọrịta ya.

Isi mmalite

1. DoD Reliability, Availability, Maintainability, and Cost Rationale Report Manual (operational availability Ao) — U.S. Office of the Secretary of Defense, 2009
2. MIL-HDBK-338B Electronic Reliability Design Handbook (exponential failure model, availability) — U.S. DoD, 1998
3. C. C. Sherbrooke — METRIC: A Multi-Echelon Technique for Recoverable Item Control (Palm’s theorem, expected backorders) — Operations Research 16(1), 1968
4. C. Palm — Analysis of the Erlang traffic formulae for busy-signal arrangements (Palm’s theorem on (S−1,S) pipelines) — Ericsson Technics No. 4, pp. 39–58, 1938
5. ITU-D Study Group 2 — Teletraffic Engineering Handbook: Erlang B recursion E_x = A·E_(x−1)/(x + A·E_(x−1)); Erlang C — ITU, 2002
6. F. P. Kelly — Loss Networks (trunk reservation) — Annals of Applied Probability 1(3), 1991
7. MIT Lincoln Laboratory — Introduction to Radar Systems, Lecture 2: radar range equation S/N = P_t G² λ² σ / ((4π)³ R⁴ k T_s B_n L) — MIT Lincoln Laboratory
8. P. Hall — Introduction to the Theory of Coverage Processes (Boolean model: vacancy = e^(−λ·E|disc|)) — Wiley, 1988
9. D. Gross, C. M. Harris — Fundamentals of Queueing Theory (M/M/c, machine-repair models) — Wiley, 2008
10. U.S. Army FM 4-0 Sustainment Operations — sustainment planning concepts (days of supply as a planning measure) — Headquarters, Department of the Army, 2026