Terms of Quality Flashcards
Quality Vs. Grade
Quality is the degree to which a set of inherent characteristics fulfill requirements. Conformanceto requirements and Fitness for Use. While grade refers to the characteristics of the product, quality refers to the stability or predictability of the product.
Manage Quality vs Control
Quality
Manage Quality is the process of executing the project
quality management plan and verifying/validating that the quality standards defined for the project will meet the desired standards. It validates the quality process, not the product, by taking a random sampling of items created in order to verify a desired level of acceptability. During Manage Quality, the quality management plan is executed. For the situational questions on the exam, it is assumed that the environment has a quality assurance initiative and a quality assurance/audit system in place. Control Quality is the process area in which the product, or the output of the process, is measured against the specifications. During Control Quality, project results are measured against the approved standard.
Design for “X”
Design for X (DfX) is a set of technical guidelines that may be used while designing a product in order to ensure the maximum functionality of the product. The X in DfX can be applied to specific aspects of product development such as reliability, cost, service, safety, and quality. Applying DfX may result in:
• Cost reduction • Superior performance • Quality advances • Customer satisfaction
Ishikawa Diagrams
Cause-and-effect diagrams, also known as fishbone, Ishikawa, or why-why diagrams), are used to decompose the identified causes of a problem statement into separate branches in order to determine the root cause of a problem. They are also used to forecast possible effects of quality defects and inaccuracies.
Histogram
A graphical representation, in the format of bar chart, that depicts the central tendency, dispersal, and shape of a statistical distribution (the frequency at which a characteristic occurs). The columns represent a characteristic and the height of the bar in each column represents the frequency of that characteristic’s occurrence.
Pareto Chart
A bar chart, ordered by occurrence frequency, depicting the number of outcomes for each identified cause. The Pareto diagram is a cumulative histogram that can be used to determine the most common issues/defects ordered by the frequency of their occurrence. This diagram also depicts a cumulative percentage of issues/defects. The Pareto diagram typically reflects the 80/20 rule, which states that, as a general rule, 80% of the problems arise from 20% of the issues/defects.
Quality Audit
A quality audit is a separate, configured technique that is performed randomly or in conformity with a set schedule. It is conducted to establish the compliance of project activities against organizational and project policies, processes, and procedures. A team external to the project or organization typically performs the quality audit in order to determine good and best practices; to determine any shortcomings or instances of non-conformity; to share good practices from similar projects; to propose positive help in the improvement of processes that will increase the team’s effectiveness; and to emphasize audit contributions in the organizational lessons learned repository. Correction of discovered deficiencies typically decreases the overall cost of quality and increases customer product acceptance.
Control Chart
A control chart (a form of run chart) depicts the process output over time. It can be used to track technical performance, schedule performance, or cost performance. The primary difference between a run chart and a control chart is that the control chart has defined control and specification limits, whereas the run chart’s limits may be adjusted.
“Run of 7”
A rule that states if seven consecutive data points are on one side of the mean (above or below) or increasing/decreasing, then the process is out of control and should be investigated.
Scatter Diagrams
A graphical representation that shows the relationship between two variables by putting one on the x axis, the other on the y axis, and analyzing the intersecting points; typically used to determine root causes or the presence of a cause-and-effect relationship.
Check Sheets
Also known as tally sheets, are utilized to organize facts in a manner that will make data regarding a potential quality problem easier to collect. A check sheet used to gather attributes data while performing an inspection is very effective for identifying the frequency with which defects occur.
Checklists
Utilized to ensure that quality activities are managed in a structural manner. Standardized checklists developed by the organization or the industry are often used.
Retrospectives
Recurring retrospectives are used to examine the proficiency of the quality processes. If any issue is discovered, an analysis of the root cause is undertaken and new approaches may be employed on a trial basis. The new approaches are then evaluated during subsequent retrospectives.
UCL/LCL
The upper and lower control limits represent the control points of the process. The process is under control if the data falls between the lower and upper control limits. This applies in all but one case: the Seven Run Rule. Typically, the upper control limit (UCL) and lower control limit (LCL) are set at +/-3 sigma.
USL/LSL
The upper and lower tolerances, sometimes called upper (USL) and lower (LSL) specification (spec) limits, are customer established and can be inside or outside the control limits. The process outcome is acceptable if the data falls between the lower and upper tolerance limits.
