Some Quality Review Points
§ everyone in the organization is responsible for the quality
(project team for destined parts while PM for project quality), PM is ultimately responsible
for the project quality
§ prevention
over inspection
§ outliers are
singular measurements outside the control limits
§ continuous improvement to ensure quality (quality assurance)
§ some costs of quality will be borne by the organization
(organization quality policy, e.g. quality audit, ISO accreditation)
§ Quality:
the degree to which a set of inherent characteristics fulfills requirements, decrease
rework/costs, increase productivity/stakeholder satisfaction
§ under ‘control’: the process is predictable and repeatable
§ PM: perform continuous improvement activities (quality assurance),
verify quality before completion of deliverables (control quality)
§ Grade (fit for use or not) vs Quality (conformance to stated requirements)
§ Accuracy (correctness) vs Precision (consistence, how closely
conforms to target, standard deviation is a measure of precision, smaller
standard deviation higher precision)
§ Quality Management Concepts
§ Crosby Zero
Defects: identify processes to remove defects, quality is built in to the
processes
§ Juran Fitness
for Use: does the product/service meet customer’s need? i) Grade, ii) Quality
conformance, iii) Reliability/maintainability, iv) Safety, v) Actual Use
§ W.
Edwards Deming: 85% of quality problem is managers’ responsibility,
develop “System of Profound Knowledge” [system = components working together to
achieve an aim] i) Appreciation for system, ii) Knowledge about variation
(special cause vs common cause) , iii) Theory of Knowledge (built up by
prediction/observation/adjustment) , iv) Psychology
§ Six
Sigma: achieve 3.4/1 mil defect level (99.999%) using DMAIC (Define, Measure,
Analyze, Implement, Control) or [Design for Six Sigma] DMADV (Define,
Measure, Analyze, Design, Validate) approach, refine the process to get rid of human
error and outside influences with precise measurements, variations are random
in nature
§ Just
In Time: eliminate build up of inventory
§ Total
Quality Management (TQM): ISO 8402 all members to center on quality to drive
customer satisfaction , refine the process of producing the product
§ Kaizen改善: implement consistent and
incremental improvement, to reduce costs, cycle time, drive customer
satisfaction using PDCA (Plan Do Check Act)
§ The Plan-Do-Check-Act cycle is a way of making small improvements and testing their
impact before you make a change to the process as a whole. It comes from W.
Edwards Deming’s work in process improvement, which popularized the cycle that
was originally invented by Walter Shewhart in the 1930s.
§ Capability
Maturity Model Integration (CMMI): improve overall software quality (design,
development and deployment)
§ ISO9000: ensures the defined processes are performed in accordance
to the plan
§ Quality Management processes are so focused on reviewing EVERY
deliverable – not just the final product, but all of the components, designs and specifications too.
Plan Quality Management
§ quality policy (either organizational or just for the project),
methods and procedures to meet the objectives and satisfy customer’s needs
§ identify the quality requirements and document how to achieve
§ Cost-benefit
Analysis: cost of implementing quality requirements against benefits
§ Cost
of Quality: lowest quality cost is prevention, highest quality cost (poor
quality) is rework and defect repair (as high as 5000 times the cost for
carrying out unit testing), lost reputation and sales, failure cost may
be internal/external (found by customer)
§ Warranty
claims are external cost of quality
§ Cost of Quality is the total cost of quality efforts throughout
the product’s lifecycle
§ cost of conformance (prevention cost, appraisal cost) vs cost of
non-conformance (failure cost [internal/external])
§ internal/external
is reference to the project (not the organization)
§ Poka Yoke (mistake proofing), Zero Quality Control (100% source
inspection), Voice of Customer and FEMA (Failure Modes of Effects Analysis) are
planning tools for quality management
§ Quality
Metrics: function points, MTBF (mean time between failure), MTTR (mean time to
repair)
§ Marginal Analysis: ROI of quality measures
§ 7 Basic Quality Tools
§ Cause-and-effect
/ Ishikawa / Fishbone Diagram: for identifying the cause
§ Flowchart:
(e.g. SIPOC diagram) for identifying failing process steps and process
improvement opportunities
§ Check
Sheets (tally sheets): collecting data/documenting steps for defeat analysis
§ Histograms:
does not consider the influence of time on the variation that exits within a
distribution
§ Pareto
Chart: based on 80/20 principle, a prioritization tool to identify critical
issues in descending order of frequency, sort of a histogram
§ Statistical
Process Control (SPC) Chart: determine if a process is stable/predictable using
statistical sampling (assessed by accuracy[conformance] and precision[standard deviation]),
identity the internally computed control limits (UCL/LCL) and specification limits (USL/LSL) by
the customer/PM
§ run
chart is similar to control chart, but without the control
§ usually
+-3sigma i.e. a range of 6 sigma
§ a form of time series
§ if a process is within control limit but beyond specification limit, the
process is experiencing common cause variation (random) that cannot be corrected by the system, management help is needed
(special cause can be tackled but NOT common cause)
§ Stability
Analysis / Zone Test: rule of seven (7 consecutive on either side of the mean = out of control), rule
of six (six consecutive with a trend = out of control), rule of ten (10 as a saw-tooth pattern
around the mean), rule of one (1 point beyond control limit) [signal in the noise]
§ Scatter
Diagram: for trending, a form of regression analysis
§ Benchmarking:
compare to past activities/standard/competition
§ Design
of Experiments (DOE): change several factors at a time for each experiment, to determine testing approaches
and their impact on cost of quality
§ Additional Quality Planning Tools
§ Loss
Function: a financial measure of the user’s dissatisfaction with product
performance
§ Matrix Diagrams: House of Quality (HOQ) used in Quality Function Deployment (QFD) (method to transform user
demands [VOC] into design quality)
§ Kano
Model: differentiate features as satisfy, delight or dissatisfy
§ Marginal
Analysis: cost-benefits analysis
§ Force
Field Analysis (FFA): reviews any proposed action with proactive and opposing
forces
§ Process Improvement Plan: process boundaries, configuration,
process metrics/efficiencies, targets for improved performance
§ Quality Checklists: checklist to verify a series of steps have
been performed
§ The goal is to refine the process so that human errors and outside
influences no longer exist, and any remaining variations are completely random
Perform Quality Assurance
§ in the Executing Process Group
§ ensures the quality standards are being
followed, to ensure unfinished works would meet the quality requirements
§ by quality assurance department or sponsor/customer not actively
involved in the project
§ primarily concerned with overall process improvement for activities and processes
(rather than the deliverable)
§ utilize the data collected in Control Quality Process
§ Quality Management Tools
§ Affinity
Diagrams: like a mind-mapping diagram, organize thoughts on how to solve
problems
§ Process
Decision Program Charts (PDPC): defines a goal and the steps involved, useful for
contingency planning
§ Interrelationship
Digraphs: maps cause-and-effect relationships for problems with multiple
variables/outcomes
§ Tree Diagrams
§ Prioritization
Matrices: define issues and alternatives that need to be prioritized for
decision, items are given a priority score through brainstorming
§ Activity Network Diagrams
§ Matrix Diagrams: e.g. ‘house of quality’ in QFD
§ Kaizen改善, Kanben看板: quality assurance methods developed by Japanese
§ Quality
Audit: to verify quality of processes, to seek improvement, identify best
practices, reduce overall cost of quality, confirm implementation of approved
changes, need quality documentations
§ Quality
Review: to review the quality management plan
§ change requests are mostly procedural changes
Control Quality
§ verify
the deliverables against customer’s specifications to ensure customer satisfaction
§ validate
the changes against the original approved change requests
§ conditional probability (events somewhat related) vs statistical independence
(events not interrelated) vs mutual exclusivity
§ statistical sampling for control quality
§ variable
(continuous) data: measurements, can do maths on e.g. average
§ attribute
(discrete) data: yes/no, no.123, just an identifier, can’t do maths on
§ QC includes the PM process (lesson learnt, budget, scope)
§ tolerance
(spec limits, deliverables acceptable) vs control limits (process acceptable)
§ if within control limit but outside tolerance: rework the process to give better precision
§ all control and execution processes may generate lesson learned
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