HKIE Professional Assessment - Logistics & Transportation Discipline cheat sheet

Bullwhip amplification: order variance ratio = Var(orders)/Var(demand); increases with lead time, batch size, and demand signal distortion.

Newsvendor critical fractile: order Q* where P(D ≤ Q*) = Cu/(Cu+Co), with Cu = underage cost, Co = overage cost.

Economic order quantity: EOQ = sqrt(2DS/(H)), where D = annual demand, S = order cost, H = holding cost per unit per year.

Safety stock for a target cycle service level: SS = z·σ_d·sqrt(L); with variable lead time, SS = z·sqrt(L·σ_d² + d²·σ_L²).

Little's Law: WIP = throughput × flow time; applies to pipelines, yards, and warehouse queues.

Square-root law of inventory pooling: combined safety stock scales with sqrt(n) for n identical independent locations.

Facility location: Weber (minimise weighted Euclidean distance) vs. centre-of-gravity vs. p-median (minimise demand-weighted network distance); set covering for coverage constraints.

Push-pull boundary (postponement decoupling point) is placed where forecast error cost equals the cost of delayed differentiation.

Highway capacity is expressed as pc/h/lane; convert to vph by dividing by peak-hour factor (PHF) and applying heavy-vehicle and driver population adjustment factors.

Level of service is graded A–F by density (pc/km/lane) on freeways and by percent time-following or average travel speed on two-lane roads.

Fundamental traffic flow identity: q = k·v (flow = density × speed); capacity occurs near the critical density, not at free-flow speed.

Greenshields linear model: v = v_f(1 − k/k_j); triangular and Greenberg models give alternative speed–density relations.

Saturation flow at signalised intersections is about 1,800–1,900 pc/h/lane; capacity = saturation flow × (effective green/cycle length).

Webster's optimal cycle: C_o = (1.5L + 5)/(1 − ΣY), where L = total lost time and Y = sum of critical flow ratios.

Horizontal curve: R = V²/(127(e + f)) with V in km/h; superelevation e and side friction f are limited by design speed and climate.

Stopping sight distance SSD = 0.278·V·t + V²/(254(f ± g)) (V in km/h, t in seconds, g = grade).

Incoterms 2020 risk-transfer points: FOB/FCA transfer at loading on board or at the carrier's terminal; CIF/CIP risk passes at shipment though cost extends to destination.

TEU = 20 ft container (~33 m³, ~21.7 t payload); FEU = 40 ft (~67 m³); 40 ft HC adds ~15% internal height.

Incoterms 2020 changed CIP to require Institute Cargo Clauses (A) all-risks cover; CIF retains minimum Clauses (C).

Load factor = payload carried / payload capacity; empty running and repositioning are the main cost drivers in road and rail freight.

Intermodal economics: rail is competitive above roughly 500–800 km, road below; transhipment cost sets the break-even distance.

Bill of lading is a receipt, a contract of carriage, and a document of title; a sea waybill is not negotiable.

Dangerous goods: IMDG Code for sea, IATA DGR for air, ADR for road Europe; UN numbers, packing groups I–III, and segregation tables apply.

Cold chain: reefer set-point vs. supply air temperature; pre-trip inspection covers set point, humidity, and fresh-air exchange.

ITS architecture layers: sensing (loops, radar, cameras, GNSS probes) → communications (DSRC/C-V2X, 4G/5G) → processing → user services (ATIS, ATMS, ATMS).

C-ITS uses 5.9 GHz ITS-G5/DSRC or C-V2X PC5 sidelink; latency targets are 10–100 ms for safety messages.

Electronic tolling: DSRC microwave (ISO 18000-6C/6B) vs. GNSS/ANPR free-flow; enforcement requires image capture and matching.

Traffic management: SCOOT (cyclic flow profiles) and SCATS (strategic adaptive) are adaptive signal systems; both adjust splits, offsets, and cycle in real time.

Warehouse management system (WMS) functions: receiving, put-away, slotting, pick-path optimisation, wave planning, and cycle counting.

EDI standards: EDIFACT (UN/EDIFACT) and ANSI X12; GS1 EPCIS for supply-chain event traceability; GS1 SSCC for pallet/carton labels.

RFID UHF (860–960 MHz) read range 1–12 m passive; NFC/HF (13.56 MHz) for short-range asset tags.

Data quality dimensions for logistics analytics: accuracy, completeness, timeliness, consistency, and granularity (SKU × location × time).

Berth productivity: moves per hour per crane; quay crane rate 25–35 moves/h; berth occupancy = ship time at berth / total time.

Container terminal capacity ≈ quay length × crane density × operating hours × moves per hour × utilisation; yard capacity is often the binding constraint.

TEU throughput vs. berth capacity: annual capacity (TEU) ≈ berth length × productivity × 365 × utilisation.

Airport runway capacity (declared) depends on runway configuration, aircraft mix, and separation rules; typical single runway 30–55 movements/h.

Airport terminal level of service uses IATA LoS A–E based on space per passenger (m²/PAX) in check-in, security, and holdroom.

Aircraft turnaround: deplaning, cleaning, catering, refuelling, boarding; narrow-body 30–45 min, wide-body 60–90 min.

Yard stacking: RTG vs. RMG; block density measured in TEU/ha; average stack height 4–5 tiers for RTG.

Port hinterland: rail share, truck turn time (target < 30 min), and gate appointment systems reduce congestion.

Four-step model: trip generation → trip distribution (gravity model) → mode choice (logit) → trip assignment (user equilibrium).

Logit mode choice: P_i = exp(V_i)/Σ exp(V_j); V_i is a linear-in-parameters utility; scale parameter matters for forecasting.

Generalised cost = fare + value of time × travel time + tolls + parking; value of time (VoT) commonly 40–60% of wage rate for commuting.

Wardrop's first principle: user equilibrium where no traveller can reduce individual cost; second principle: system optimum minimises total cost (requires congestion pricing).

Cost–benefit analysis: NPV = Σ (B_t − C_t)/(1+r)^t; decision rules NPV > 0, BCR > 1, and IRR > discount rate.

Elasticity of demand: %ΔQ/%ΔP; short-run fuel price elasticity typically −0.2 to −0.4; long-run larger.

Induced demand: new capacity lowers travel time, attracting trips previously suppressed or shifted from other modes/routes.

Externalities: congestion, air pollution, noise, and accidents are unpriced; Pigouvian taxes internalise marginal external cost.

ALARP principle: risk reduced as low as reasonably practicable; gross disproportion test between cost of control and risk reduction.

Risk matrix: likelihood × consequence; risk score bands drive mitigation and escalation.

Fault tree analysis (deductive) and event tree analysis (inductive) for accident modelling; bow-tie combines threats, top event, and consequences.

Road safety: crash rate per 100 million vehicle-km; Haddon matrix (host, agent, environment × pre-crash, crash, post-crash).

Vision Zero and Safe System: humans are fragile; roads and vehicles should absorb error; speed limits set by biomechanical tolerance (~30 km/h for pedestrians).

Hours of service: EU drivers' rules - 9 h daily driving (extendable to 10 h twice weekly), 45 h weekly rest, 15-min break after 4.5 h then 30 min.

Dangerous goods classification: 9 UN classes; packing groups I (high danger), II, III; transport document and emergency information required.

Workplace safety: ISO 45001, risk assessment, permit-to-work for confined spaces, and lifting operations (SWL, WLL).

Well-to-wheel (WTW) vs. tank-to-wheel (TTW) emissions accounting; WTW includes fuel production and distribution.

CO2 from fuel: diesel ≈ 2.68 kg CO2/L; petrol ≈ 2.31 kg CO2/L; grid electricity depends on emission factor (kg CO2/kWh).

Scope 1 (direct), Scope 2 (purchased energy), Scope 3 (value chain) under GHG Protocol; logistics emissions are mostly Scope 3.

GLEC Framework / ISO 14083 provide the methodology for transport chain emissions (g CO2e per tonne-km).

Modal emission intensity: air freight ~500–1,000 g CO2e/t-km; road ~60–150; rail ~20–40; sea ~10–20 (indicative).

Euro standards: Euro VI for heavy-duty diesel (NOx limit 0.4 g/kWh); Euro 7 extends to brake and tyre particulates.

Circular economy: reduce, reuse, recycle, recover; reverse logistics handles returns, packaging, and end-of-life assets.

Energy management: ISO 50001; energy baseline and EnPI (energy performance indicator) track improvement.

Project phases: initiation → planning → execution → monitoring/control → closure; stage gates authorise progression.

Earned value: CV = EV − AC; SV = EV − PV; CPI = EV/AC; SPI = EV/PV; EAC = BAC/CPI (typical) or AC + (BAC − EV).

Critical path method: longest path through the network; float = LS − ES = LF − EF; zero float = critical.

Risk register: probability × impact; response strategies avoid, mitigate, transfer, accept.

Contracts: FIDIC Red/Yellow/Silver Books (construction, plant, EPC turnkey); NEC4 uses defined cost and pain/gain share.

Professional conduct: competence, honesty, confidentiality, conflict-of-interest disclosure, public safety paramount; HKIE membership requires CPD and code of conduct.

Design liability and buildability reviews; independent checking of safety-critical calculations.

Stakeholder engagement and environmental impact assessment (EIA) under statutory process before construction consent.

Autonomous mobile robots (AMR) vs. automated guided vehicles (AGV): AMRs navigate by SLAM and avoid obstacles; AGVs follow fixed guide paths.

Goods-to-person picking (AS/RS, shuttle, cube storage) raises pick rates and reduces travel; payback depends on order profile and SKU velocity.

Digital twin: virtual replica synchronised with real asset via IoT; used for yard, terminal, and network simulation.

Predictive analytics: demand forecasting with ML (gradient boosting, LSTM); measure with MAPE, MAE, RMSE, and bias.

E-commerce logistics: last-mile cost is 40–50% of total delivery cost; locker and click-and-collect reduce failed delivery.

Blockchain in supply chain: provenance and document traceability; performance limited by throughput and off-chain data trust.

Drone and autonomous trucking: regulatory airspace (BVLOS) and platooning rules constrain deployment.

Cybersecurity: OT/IT convergence in terminals and warehouses; IEC 62443 for industrial control system security.