A precedence diagram is a building block for more advanced techniques in operations and project management. Precedence diagrams are used as inputs to PERT and Gantt charts, line balancing, and Critical Path Method (topics of future installments of “The Third Degree.”)
Many resources discuss precedence diagramming as a component of the techniques mentioned above. However, the fact that it can be used for each of these purposes, and others, warrants a separate treatment of the topic. Separate treatment is also intended to encourage reuse, increasing the value of each diagram created.
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In many organizations, complaints can be heard that there are too many programs and initiatives targeting too many objectives. These complaints may come from staff or management; many of them may even be valid. The response to this situation, however, is often misguided and potentially dangerous. To streamline efforts and improve performance – ostensibly, at least – managers and executives may discontinue or merge programs. Done carelessly, consolidation can be de facto termination. A particularly egregious example of this practice is to combine safety and 5S. ![]()
Unintended consequences come in many forms and have many causes. “Revenge effects” are a special category of unintended consequences, created by the introduction of a technology, policy, or both that produces outcomes in contradiction to the desired result. Revenge effects may exacerbate the original problem or create a new situation that is equally undesirable if not more objectionable.
Discussions of revenge effects often focus on technology – the most tangible cause of a predicament. However, “[t]echnology alone usually doesn’t produce a revenge effect.” It is typically the combination of technology, policy, (laws, regulations, etc.), and behavior that endows a decision with the power to frustrate its own intent. This installment of “The Third Degree” explores five types of revenge effects, differentiates between revenge and other effects, and discusses minimizing unanticipated unfavorable outcomes. The Law of Unintended Consequences can be stated in many ways. The formulation forming the basis of this discussion is as follows:
“The Law of Unintended Consequences states that every decision or action produces outcomes that were not motivations for, or objectives of, the decision or action.” Like many definitions, this statement of “the law” may seem obscure to some and obvious to others. This condition is often evidence of significant nuance. In the present case, much of the nuance has developed as a result of the morphing use of terms and the contexts in which these terms are most commonly used. The transformation of terminology, examples of unintended consequences, how to minimize negative effects, and more are explored in this installment of “The Third Degree.” An organization’s safety-related activities are critical to its performance and reputation. The profile of these activities rises with public awareness or concern. Nuclear power generation, air travel, and freight transportation (e.g. railroads) are commonly-cited examples of high-profile industries whose safety practices are routinely subject to public scrutiny.
When addressing “the public,” representatives of any organization are likely to speak in very different terms than those presented to them by technical “experts.” After all, references to failure modes, uncertainties, mitigation strategies, and other safety-related terms are likely to confuse a lay audience and may have an effect opposite that desired. Instead of assuaging concerns with obvious expertise, speaking above the heads of concerned citizens may prompt additional demands for information, prolonging the organization’s time in an unwanted spotlight. In the example cited above, intentional obfuscation may be used to change the beliefs of an external audience about the safety of an organization’s operations. This scenario is familiar to most; myriad examples are provided by daily “news” broadcasts. In contrast, new information may be shared internally, with the goal of increasing knowledge of safety, yet fail to alter beliefs about the organization’s safety-related performance. This phenomenon, much less familiar to those outside “the safety profession,” has been dubbed “probative blindness.” This installment of “The Third Degree” serves as an introduction to probative blindness, how to recognize it, and how to combat it. As mentioned in the introduction to the AIAG/VDA aligned standard (“Vol. V: Alignment”), the new FMEA Handbook, is a significant expansion of its predecessors. A substantial portion of this expansion is the introduction of a new FMEA type – the Supplemental FMEA for Monitoring and System Response (FMEA-MSR).
Modern vehicles contain a plethora of onboard diagnostic tools and driver aids. The FMEA-MSR is conducted to evaluate these tools for their ability to prevent or mitigate Effects of Failure during vehicle operation. Discussion of FMEA-MSR is devoid of comparisons to classical FMEA, as it has no correlate in that method. In this installment of the “FMEA” series, the new analysis will be presented in similar fashion to the previous aligned FMEA types. Understanding the aligned Design FMEA method is critical to successful implementation of FMEA-MSR; this presentation assumes the reader has attained sufficient competency in DFMEA. Even so, review of aligned DFMEA (Vol. VI) is highly recommended prior to pursuing FMEA-MSR. To conduct a Process FMEA according to AIAG/VDA alignment, the seven-step approach presented in Vol. VI (Aligned DFMEA) is used. The seven steps are repeated with a new focus of inquiry. Like the DFMEA, several system-, subsystem-, and component-level analyses may be required to fully understand a process.
Paralleling previous entries in the “FMEA” series, this installment presents the 7-step aligned approach applied to process analysis and the “Standard PFMEA Form Sheet.” Review of classical FMEA and aligned DFMEA is recommended prior to pursuing aligned PFMEA; familiarity with the seven steps, terminology used, and documentation formats will make aligned PFMEA more comprehensible. To differentiate it from “classical” FMEA, the result of the collaboration between AIAG (Automotive Industry Action Group) and VDA (Verband der Automobilindustrie) is called the “aligned” Failure Modes and Effects Analysis process. Using a seven-step approach, the aligned analysis incorporates significant work content that has typically been left on the periphery of FMEA training, though it is essential to effective analysis.
In this installment of the “FMEA” series, development of a Design FMEA is presented following the seven-step aligned process. Use of an aligned documentation format, the “Standard DFMEA Form Sheet,” is also demonstrated. In similar fashion to the classical DFMEA presentation of Vol. III, the content of each column of the form will be discussed in succession. Review of classical FMEA is recommended prior to attempting the aligned process to ensure a baseline understanding of FMEA terminology. Also, comparisons made between classical and aligned approaches will be more meaningful and, therefore, more helpful. Preparations for Process Failure Modes and Effects Analysis (Process FMEA) (see Vol. II) occur, in large part, while the Design FMEA undergoes revision to develop and assign Recommended Actions. An earlier start, while ostensibly desirable, may result in duplicated effort. As a design evolves, the processes required to support it also evolve; allowing a design to reach a sufficient level of maturity to minimize process redesign is an efficient approach to FMEA.
In this installment of the “FMEA” series, how to conduct a “classical” Process FMEA (PFMEA) is presented as a close parallel to that of DFMEA (Vol. III). Each is prepared as a standalone reference for those engaged in either activity, but reading both is recommended to maintain awareness of the interrelationship of analyses. In the context of Failure Modes and Effects Analysis (FMEA), “classical” refers to the techniques and formats that have been in use for many years, such as those presented in AIAG’s “FMEA Handbook” and other sources. Numerous variations of the document format are available for use. In this discussion, a recommended format is presented; one that facilitates a thorough, organized analysis.
Preparations for FMEA, discussed in Vol. II, are agnostic to the methodology and document format chosen; the inputs cited are applicable to any available. In this installment of the “FMEA” series, how to conduct a “classical” Design FMEA (DFMEA) is presented by explaining each column of the recommended form. Populating the form columns in the proper sequence is only an approximation of analysis, but it is a very useful one for gaining experience with the methodology. Failure Modes and Effects Analysis (FMEA) is most commonly used in product design and manufacturing contexts. However, it can also be helpful in other applications, such as administrative functions and service delivery. Each application context may require refinement of definitions and rating scales to provide maximum clarity, but the fundamentals remain the same.
Several standards have been published defining the structure and content of Failure Modes and Effects Analyses (FMEAs). Within these standards, there are often alternate formats presented for portions of the FMEA form; these may also change with subsequent revisions of each standard. Add to this variety the diversity of industry and customer-specific requirements. Those unbeholden to an industry-specific standard are free to adapt features of several to create a unique form for their own purposes. The freedom to customize results in a virtually limitless number of potential variants. Few potential FMEA variants are likely to have broad appeal, even among those unrestricted by customer requirements. This series aims to highlight the most practical formats available, encouraging a level of consistency among practitioners that maintains Failure Modes and Effects Analysis as a portable skill. Total conformity is not the goal; presenting perceived best practices is. An effective safety program requires identification and communication of hazards that exist in a workplace or customer-accessible area of a business and the countermeasures in place to reduce the risk of an incident. The terms hazard, risk, incident, and others are used here as defined in “Safety First! Or is It?”
A hazard map is a highly-efficient instrument for conveying critical information regarding Safety, Health, and Environmental (SHE) hazards due to its visual nature and standardization. While some countermeasure information can be presented on a Hazard Map, it is often more salient when presented on a corollary Body Map. Use of a body map is often a prudent choice; typically, the countermeasure information most relevant to many individuals pertains to the use of personal protective equipment (PPE). The process used to develop a Hazard Map and its corollary Body Map will be presented. Many organizations adopt the “Safety First!” mantra, but what does it mean? The answer, of course, differs from one organization, person, or situation to another. If an organization’s leaders truly live the mantra, its meaning will be consistent across time, situations, and parties involved. It will also be well-documented, widely and regularly communicated, and supported by action.
In short, the “Safety First!” mantra implies that an organization has developed a safety culture. However, many fall far short of this ideal; often it is because leaders believe that adopting the mantra will spur the development of safety culture. In fact, the reverse is required; only in a culture of safety can the “Safety First!” mantra convey a coherent message or be meaningful to members of the organization. Choosing effective strategies for waging war against error in manufacturing and service operations requires an understanding of “the enemy.” The types of error to be combatted, the sources of these errors, and the amount of error that will be tolerated are important components of a functional definition (see Vol. I for an introduction).
The traditional view is that the amount of error to be accepted is defined by the specification limits of each characteristic of interest. Exceeding the specified tolerance of any characteristic immediately transforms the process output from “good” to “bad.” This is a very restrictive and misleading point of view. Much greater insight is provided regarding product performance and customer satisfaction by loss functions. Myriad tools have been developed to aid collaboration of team members that are geographically separated. Temporally separated teams receive much less attention, despite this type of collaboration being paramount for success in many operations.
To achieve performance continuity in multi-shift operations, an effective pass-down process is required. Software is available to facilitate pass-down, but is not required for an effective process. The lowest-tech tools are often the best choices. A structured approach is the key to success – one that encourages participation, organization, and consistent execution. A person’s first interaction with a business is often his/her experience in its parking lot. Unless an imposing edifice dominates the landscape, to be seen from afar, a person’s first impression of what it will be like to interface with a business is likely formed upon entering the parking lot. It is during this introduction to the facility and company that many expectations are formed. “It” starts in the parking lot. “It” is customer satisfaction.
There is a “universal sequence for quality improvement,” according to the illustrious Joseph M. Juran, that defines the actions to be taken by any team to effect change. This includes teams pursuing error- and defect-reduction initiatives, variation reduction, or quality improvement by any other description.
Two of the seven steps of the universal sequence are “journeys” that the team must take to complete its problem-solving mission. The “diagnostic journey” and the “remedial journey” comprise the core of the problem-solving process and, thus, warrant particular attention. Of the “eight wastes of lean,” the impacts of defects may be the easiest to understand. Most find the need to rework or replace a defective part or repeat a faulty service, and the subsequent costs, to be intuitive. The consequences of excess inventory, motion, or transportation, however, may require a deeper understanding of operations management to fully appreciate.
Conceptually, poka yoke (poh-kah yoh-keh) is one of the simplest lean tools; at least it was at its inception. Over time, use of the term has morphed and expanded, increasing misuse and confusion. The desire to appear enlightened and lean has led many to misappropriate the term, applying it to any mechanism used, or attempt made, to reduce defects. Poka yoke is often conflated with other process control mechanisms, including engineering controls and management controls. To effectively reduce the occurrence of errors and resultant defects, it is imperative that process managers differentiate between poka yoke devices, engineering controls, and management controls. Understanding the capabilities and limitations of each allows appropriate actions to be taken to optimize the performance of any process. Every organization wants error to be kept at a minimum. The dedication to fulfilling this desire, however, often varies according to the severity of consequences that are likely to result. Manufacturers miss delivery dates or ship faulty product; service providers fail to satisfy customers or damage their property; militaries lose battles or cause civilian casualties; all increase the cost of operations.
You probably have some sensitivity to the effects errors have on your organization and its partners. This series explores strategies, tools, and related concepts to help you effectively combat error and its effects. This is your induction; welcome to The War on Error. Uses of augmented reality (AR) in various industries has been described in previous installments of “Augmented Reality” (Part 1, Part 2). In this installment, we will explore AR applications aimed at improving customer experiences in service operations. Whether creating new service options or improving delivery of existing services, AR has the potential to transform our interactions with service providers.
Front-office operations are mostly transparent due to customer participation. Customer presence is a key characteristic that differentiates services from the production of goods. Thus, technologies employed in service industries are often highly visible. This can be a blessing or a curse. Some of the augmented reality (AR) applications most likely to attract popular attention were presented in “Part 1: An Introduction to the Technology.” When employed by manufacturing companies, AR is less likely to be experienced directly by the masses, but may have a greater impact on their lives. There may be a shift, however, as AR applications pervade product development and end-user activities.
In this installment, we look at AR applications in manufacturing industries that improve operations, including product development, quality control, and maintenance. Some are involved directly in the transformation of materials to end products, while others fill supporting roles. The potential impact on customer satisfaction that AR use provides will also be explored. The use of digital technologies in commercial applications is continually expanding. Improvements in virtual reality (VR) systems have increased the practical range of opportunities for their use across varied industries.
As discussed with respect to other technologies experiencing accelerated development and expansion, several definitions of “virtual reality” may be encountered. Researchers and practitioners may disagree on which applications qualify for use of the term. For our purposes, we will use a simple description of virtual reality: “Virtual reality” is an experience created, using a digital twin or other model, where
Digital Twin technology existed long before this term came into common use. Over time, existing technology has advanced, new applications and research initiatives have surfaced, and related technologies have been developed. This lack of centralized “ownership” of the term or technology has led to the proliferation of differing definitions of “digital twin.”
Some definitions focus on a specific application or technology – that developed by those offering the definition – presumably to coopt the term for their own purposes. Arguably, the most useful definition, however, is the broadest – one that encompasses the range of relevant technologies and applications, capturing their corresponding value to the field. To this end, I offer the following definition of digital twin: An electronic representation of a physical entity – product, machine, process, system, or facility – that aids understanding of the entity’s design, operation, capabilities, or condition. Troubleshooting a system can be guided by instructions created by its developer or someone with extensive experience operating and maintaining similar systems. Without a specific context, however, a troubleshooting process can be very difficult to describe. There is an enormous number of variables that could potentially warrant consideration. The type of system (mechanical, power transmission, fluid power, electrical, motion control, etc.), operating environment (indoor, outdoor, arid, tropical, arctic, etc.), and severity of duty are only the beginning.
The vast array of systems and situations that could be encountered requires that troubleshooting be learned as a generalized skill. What tool set could be more general, more universally applicable, than our senses of sight, hearing, smell, taste, touch, and the most powerful of all, common sense? Spaghetti Diagrams The origin of the spaghetti diagram – when and where it was first used or who first recognized its resemblance to a plate of pasta – is not well known. What is clear is that this simple tool can be a very powerful representation of waste in various processes. An easily-understood visual presentation often provides the impetus needed for an organization to advance its improvement efforts.
While flow charts (see Vol. II) depict logical progressions through a process, spaghetti diagrams illustrate physical progressions. The movements tracked may be made by people, materials, paperwork, or other entities. As is the case with other maps, spaghetti diagrams can be created in very simple form, with information added as improvement efforts advance. |
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