CIE key terms

One of eighteen basic motion elements, such as grasp, reach, or transport, into which manual work is decomposed so that wasteful motions can be identified and eliminated.

Systematic observation and analysis of the body movements a worker uses to perform a task, aimed at simplifying the method, reducing fatigue, and improving productivity.

Detailed study of very short work elements, often using slow-motion or frame-by-frame video, to separate productive motions from ineffective ones and to refine the method.

Work measurement technique that uses a stopwatch and a defined rating procedure to determine the time a qualified worker needs to perform a task at a normal pace.

A system of published motion-time tables that lets an analyst build a task time by summing standard values for the basic motions involved, without observing a worker.

Analyst judgment that compares an observed worker's pace with the analyst's concept of normal pace, producing a factor used to adjust observed times to a normal basis.

Observed task time multiplied by the performance rating, representing the time a worker of average skill and effort would need at a standard pace.

Percentage added to normal time to cover personal needs, unavoidable delays, and fatigue, so that the resulting standard can be sustained over a full shift.

Total time allowed for one unit of work when performed by a qualified worker using a specified method at a normal pace, including all applicable allowances.

Measurement method in which random observations record what workers or machines are doing at those instants, and the proportions estimate activity shares and idle time.

Model in which the labor hours required per unit decline by a constant percentage each time cumulative output doubles, reflecting improved skill and process familiarity.

Optimization method that maximizes or minimizes a linear objective subject to linear constraints, commonly used for product mix, blending, and allocation decisions.

Special linear program that finds the least-cost pattern for shipping goods from several sources to several destinations when supplies and demands are fixed.

Special linear program that matches each job or task to exactly one resource, minimizing total cost or time when each resource handles one task.

Examination of how an optimal solution or decision changes when input data such as costs, capacities, or demand estimates vary within plausible ranges.

Mathematical study of waiting lines that predicts average queue length, waiting time, and utilization from arrival rates, service rates, and the number of servers.

Imitation of a system's behavior over time using a computer model with random inputs, used when analytical formulas cannot capture the system's complexity.

Technique that repeatedly draws random values from input probability distributions and runs the model many times to estimate the distribution of outcomes.

Estimating future demand from historical data and judgment, using methods such as moving averages, exponential smoothing, or causal regression models.

Forecasting method that updates the previous forecast by adding a fraction of the most recent forecast error, with the smoothing constant controlling responsiveness.

Average of the absolute differences between forecast values and actual values over a set of periods, used to compare forecast accuracy across methods.

Order size that minimizes the sum of annual ordering cost and annual holding cost, given steady demand and known, constant costs per order and per unit.

Extra inventory held to absorb variability in demand or replenishment lead time, reducing the risk of stockouts between orders.

Inventory level at which a new order is triggered, typically equal to expected demand during lead time plus safety stock.

Planning system that uses a bill of materials, inventory records, and a master production schedule to time the release of orders for components and raw materials.

Structured list of all components, subassemblies, and quantities needed to make one unit of a finished product, organized by product levels.

Statement of which end items will be produced and in what quantities during each period of a planning horizon, driving material requirements planning.

Medium-range planning that sets overall production rates, workforce levels, and inventory holdings to meet expected demand at minimum total cost.

Matrix showing the number of trips or quantity of material moved between each pair of departments or locations, used to guide layout arrangement.

Structured procedure that ranks the closeness relationships desired between departments, then converts them into a block layout and adjusts for space and building constraints.

Diagram that rates the closeness importance of each pair of departments with letter codes, used to develop layouts when material flows are minor compared with service interactions.

Time-ordered plot of a process statistic with statistically derived control limits, used to distinguish common-cause variation from special-cause variation.

Ratio comparing the width of a specification range with the natural spread of a stable process, indicating how well the process can meet tolerances.

Identifiable, nonrandom source of variation in a process, such as a worn tool or a new operator, detected as a signal on a control chart.

Quality procedure that inspects a sample from a lot and accepts or rejects the whole lot based on the number of defects found, governed by defined risk levels.

Graph showing the probability of accepting a lot for each possible lot quality level under a given sampling plan, revealing producer and consumer risk.

Equivalent value today of a stream of future cash flows, obtained by discounting each flow at a stated interest rate.

Discount rate at which a project's present worth of inflows equals the present worth of outflows, making its net present value zero.

Length of time required for cumulative cash inflows to recover the initial investment, used as a simple screening measure of liquidity and risk.

Allocation of the cost of a durable asset over its useful life for accounting and tax purposes, using methods such as straight-line or declining balance.

Study and measurement of human body dimensions and reach envelopes, used to size workspaces, tools, and equipment so most users can operate them comfortably.

Model that computes a recommended weight limit for a manual lifting task from factors such as horizontal distance, vertical height, twist, frequency, and coupling quality.

Rapid Upper Limb Assessment, a worksheet-based screening tool that scores postures of the neck, trunk, and arms together with load and repetition to flag ergonomic risk.

Diagram of the material and information flows required to deliver a product family, annotated with cycle times and inventories to expose waste and delay.

Available production time divided by customer demand during that period, setting the pace at which one unit must be completed to meet demand.

Card or signal that authorizes production or withdrawal of a standard container of material, pulling work through the process in response to downstream consumption.

Design feature that prevents a mistake from being made or makes an error immediately obvious, eliminating the need to rely on operator vigilance.

Root-cause questioning technique that repeatedly asks why a problem occurred until the underlying process failure, rather than a symptom, is identified.

Product of availability, performance, and quality rates for a piece of equipment, expressing how much of its theoretically productive time yields good output.