LPSCE flashcards

34 cards. Read the term and the definition here. The deck at the top of this page is optional.

Takt time

Available production time divided by customer demand. It sets the pace the process must meet to satisfy demand without overproduction, and cycle time above takt signals a capacity gap.

Overproduction waste

Producing more, sooner, or faster than the next process needs. It is considered the worst waste because it hides defects, consumes inventory, and generates waiting, transport, and motion waste.

Value-added activity

Work the customer would pay for that transforms the product or information and is done correctly the first time. Activities failing any of the three criteria are business or non-value-added waste.

Poka-yoke

An error-proofing device or design that prevents a mistake from being made or makes it immediately obvious. It is preferred over inspection because it stops defects at the source rather than detecting them later.

Kanban

A visual signal that authorizes replenishment or production in a pull system. It limits work in process by allowing upstream work only when a downstream consumer signals a need.

Little's Law

Work in process equals throughput multiplied by flow time. It shows that reducing WIP at constant throughput shortens lead time, which is a core argument for limiting work in process.

DPMO

Defects per million opportunities, calculated as defects divided by the product of units and opportunities per unit, then multiplied by one million. It converts defect counts into a comparable sigma level.

Rolled throughput yield

The product of the first-pass yields of every step in a process. Because yields multiply, RTY is always less than or equal to the lowest individual step yield.

Six Sigma target

A long-term performance level of 3.4 defects per million opportunities, which corresponds to 4.5 short-term sigma after allowing the customary 1.5 sigma process shift.

DMAIC

The five-phase improvement cycle: Define, Measure, Analyze, Improve, Control. It applies to existing processes, with tollgate reviews confirming deliverables before the team advances to the next phase.

Cp versus Cpk

Cp is specification width divided by six sigma and ignores centering. Cpk subtracts the distance from the mean to the nearer specification limit and penalizes off-center processes.

CTQ

Critical to Quality, a measurable characteristic translated from a customer need. CTQs convert vague voice-of-customer statements into specifications the process can be measured and controlled against.

SIPOC diagram

A high-level map of Suppliers, Inputs, Process, Outputs, and Customers. It defines project scope boundaries and clarifies who supplies inputs and who receives outputs before detailed mapping begins.

Kano model

A customer-need classification with must-be, performance, and delighter categories. Must-be gaps cause dissatisfaction when missing but do not delight when present, so they are baseline requirements.

SMART goal

A goal statement that is Specific, Measurable, Achievable, Relevant, and Time-bound. In a charter it includes a quantified baseline, a target, and a deadline for achievement.

Problem statement rule

A charter problem statement must be measurable and time-bounded and must describe the gap without naming a cause or a solution. Naming either prematurely biases the analysis.

Gage R&R

A measurement systems study separating repeatability, the variation when one appraiser measures the same item twice, from reproducibility, the variation between appraisers. Under 10 percent of tolerance is acceptable.

Repeatability versus reproducibility

Repeatability is equipment variation within one appraiser on the same parts. Reproducibility is appraiser variation, the difference in average readings between operators using the same gage.

Ppk versus Cpk

Ppk uses the overall long-term standard deviation across all data. Cpk uses within-subgroup short-term sigma, so Cpk is typically higher and reflects the process potential when stable.

Attribute data

Discrete data such as pass or fail, counted rather than measured. It carries less information per observation, so larger samples are needed to reach the same statistical confidence as continuous data.

Process capability requirement

Capability indices are valid only when the process is in statistical control. A Cpk computed on an unstable process reflects mixed distributions and cannot predict future performance.

Type I error

Rejecting a true null hypothesis, also called alpha. It is the risk of declaring a difference that does not exist, and lowering alpha reduces this risk at the cost of statistical power.

Statistical power

The probability of correctly rejecting a false null hypothesis, equal to one minus beta. Power increases with larger sample size, larger effect size, and lower process variation.

p-value

The probability of observing a result at least as extreme as the sample data if the null hypothesis is true. A p-value below alpha leads to rejecting the null hypothesis.

5 Whys

An iterative questioning technique that asks why repeatedly until the systemic root cause is reached. It stops when the cause is actionable and within the team's control to change.

FMEA RPN

Risk Priority Number, the product of severity, occurrence, and detection ratings. Higher values prioritize action, though high severity alone can require corrective action regardless of RPN.

SMED

Single-Minute Exchange of Die, a method that converts internal setup tasks, which require the machine stopped, into external tasks done while it runs, thereby cutting changeover time.

Design of experiments

A structured method that varies multiple factors together to estimate main effects and interactions. It uses fewer runs than one-factor-at-a-time testing and reveals interaction effects that sequential testing misses.

Pilot test

A limited-scale trial of a proposed solution with predefined success metrics. It validates impact and surfaces implementation problems before full deployment, reducing the risk of a failed rollout.

Standard work

Documented current best practice specifying takt time, work sequence, and standard in-process inventory. It provides the baseline from which further improvement is measured and controlled.

Control chart purpose

To separate common-cause variation, inherent to the process, from special-cause variation from identifiable events. Only special causes justify local intervention; tampering with common cause increases variation.

Control versus specification limits

Control limits are computed from process data and describe what the process actually does. Specification limits come from customer requirements, so a process can be in control yet incapable.

p-chart

An attribute control chart plotting the proportion defective per subgroup. It accommodates varying subgroup sizes, unlike the np-chart, which requires a constant sample size.

RACI matrix

A responsibility assignment grid for Responsible, Accountable, Consulted, and Informed roles. Each task should have exactly one accountable owner, while several people may be responsible for doing the work.