Q
QCD
Abbreviation for quality, cost, delivery.
Q chart
A control chart for evaluating the stability of a process in terms of a quality score. The quality score is the weighted sum of the count of events of various classifications, where each classification is assigned a weight. Syn: quality chart, quality score chart.
QFD
Abbreviation for quality function deployment.
QRP
Abbreviation for quick response program.
Qualifiers
Syn: order qualifiers. See: order losers, order winners.
Qualitative forecasting techniques
An approach to forecasting that is based on intuitive or judgmental evaluation. It is used generally when data are scarce, not available, or no longer relevant. Common types of qualitative techniques include: personal insight, sales force estimates, panel consensus, market research, visionary forecasting, and the Delphi method. Examples include developing long-range projections and new product introduction.
Quality
Conformance to requirements or fitness for use. Quality can be defined through five principal approaches: (1) Transcendent quality is an ideal, a condition of excellence. (2) Product-based quality is based on a product attribute. (3) User-based quality is fitness for use. (4) Manufacturing-based quality is conformance to requirements. (5) Value-based quality is the degree of excellence at an acceptable price. Also, quality has two major components: (1) quality of conformance—quality is defined by the absence of defects, and (2) quality of design—quality is measured by the degree of customer satisfaction with a product’s characteristics and features.
Quality assurance/control
Two terms that have many interpretations because of the multiple definitions for the words “assurance” and “control.” For example, “assurance” can mean the act of giving confidence, the state of being certain, or the act of making certain; “control” can mean an evaluation to indicate needed corrective responses, the act of guiding, or the state of a process in which the variability is attributable to a constant system of chance causes. One definition of quality assurance is all the planned and systematic activities implemented within the quality system that can be demonstrated to provide confidence that a good or service will fulfill requirements for quality. One definition for quality control is the operational techniques and activities used to fulfill requirements for quality. Often, however, quality assurance and quality control are used interchangeably, referring to the actions performed to ensure the quality of a good, service, or process. See: quality control.
Quality at the source
A producer’s responsibility to provide 100% acceptable quality material to the consumer of the material. The objective is to reduce or eliminate shipping or receiving quality inspections and line stoppages as a result of supplier defects.
Quality audit
A systematic, independent examination and review to determine whether quality activities and related results comply with planned arrangements and whether these arrangements are implemented effectively and are suitable to achieve the objectives.
Quality chart
Syn: Q chart.
Quality circle
A small group of people who normally work as a unit and meet frequently to uncover and solve problems concerning the quality of items produced, process capability, or process control. See: small group improvement activity.
Quality control
The process of measuring quality conformance by comparing the actual with a standard for the characteristic and acting on the difference. See: quality assurance/control.
Quality, cost, delivery (QCD)
Key measurements of customer satisfaction. Kaizen activity strives to improve these measurements.
Quality costs
The overall costs associated with prevention activities and the improvement of quality throughout the firm before, during, and after production of a product. These costs fall into four recognized categories: internal failures, external failures, appraisal costs, and prevention costs. Internal failure costs relate to problems before the product reaches the customer. These usually include rework, scrap, downgrades, reinspection, retest, and process losses. External failure costs relate to problems found after the product reaches the customer. These usually include such costs as warranty and returns. Appraisal costs are associated with the formal evaluation and audit of quality in the firm. Typical costs include inspection, quality audits, testing, calibration, and checking time. Prevention costs are those caused by improvement activities that focus on reducing failure and appraisal costs. Typical costs include education, quality training, and supplier certification.
Quality engineering
The engineering discipline concerned with improving the quality of products and processes.
Quality function deployment (QFD)
A methodology designed to ensure that all the major requirements of the customer are identified and subsequently met or exceeded through the resulting product design process and the design and operation of the supporting production management system. QFD can be viewed as a set of communication and translation tools. QFD tries to eliminate the gap between what the customer wants in a new product and what the product is capable of delivering. QFD often leads to a clear identification of the major requirements of the customers. These expectations are referred to as the voice of the customer (VOC). See: house of quality.
Quality loss function
A parabolic approximation of the quality loss that occurs when a quality characteristic deviates from its target value. The quality loss function is expressed in monetary units: the cost of deviating from the target increases quadratically as the quality characteristic moves farther from the target. The formula used to compute the quality loss function depends on the type of quality characteristic being used. The quality loss function was first introduced in this form by Genichi Taguchi.
Quality score chart
Syn: Q chart.
Quality tree
An analytical tool that visualizes that quality is composed of four layers of achievement: (1) inspection, (2) process measurement and improvement, (3) process control, and (4) design for quality.
Quality trilogy
A three-pronged approach to managing quality proposed by Joseph Juran. The three legs are quality planning (developing the products and processes required to meet customer needs), quality control (meeting product and process goals), and quality improvement (achieving unprecedented levels of performance). Syn: Juran trilogy.
Quantitative forecasting techniques
An approach to forecasting where historical demand data is used to project future demand. Extrinsic and intrinsic techniques are typically used. See: extrinsic forecasting method, intrinsic forecasting method.
Quantity-based order system
Syn: fixed reorder quantity inventory model.
Quantity discount
A price reduction allowance determined by the quantity or value of a purchase.
Quantity per
The quantity of a component to be used in the production of its parent. This value is stored in the bill of material and is used to calculate the gross requirements for components during the explosion process of MRP.
Quarantine
The setting aside of items from availability for use or sale until all required quality tests have been performed and conformance certified.
Question mark
In marketing, a slang term for a low market share but high growth rate product. See: growth share matrix.
Queue
A waiting line. In manufacturing, the jobs at a given work center waiting to be processed. As queues increase, so do average queue time and work-in-process inventory.
Queue ratio
The ratio of the hours of slack within the job to the queue originally scheduled.
Queue time
The amount of time a job waits at a work center before setup or work is performed on the job. Queue time is one element of total manufacturing lead time. Increases in queue time result in direct increases to manufacturing lead time and work-in-process inventories.
Queuing theory
The collection of models dealing with waiting line problems, e.g., problems for which customers or units arrive at some service facility at which waiting lines or queues may build. Syn: waiting line theory.
Quick asset ratio
An activity ratio of cash, marketable securities, and accounts receivable to current liabilities. This measurement of liquidity is more rigorous than the current ratio. Syn: acid test ratio.
Quick response program (QRP)
A system of linking final retail sales with production and shipping schedules back through the chain of supply; employs point-of-sale scanning and electronic data interchange, and may use direct shipment from a factory to a retailer.
Quotation
A statement of price, terms of sale, and description of goods or services offered by a supplier to a prospective purchaser; a bid. When given in response to an inquiry, it is usually considered an offer to sell. See: bid.
Quotation expiration date
The date on which a quoted price is no longer valid.