A. ADAM  SMITH
B. ELI WHITNEY
C. FREDERICK TAYLOR
D. LORD MOUNTBATTEN
E. JAY FORRESTER
F. W. EDWARD DEMING

SYSTEMS DEFINED

A. DEFINITION
B. PROPERTIES
C. CLASSIFICATIONS

                                   SYSTEM ENGINEERING

A. DEFINITION
B. PROCESS
C. MANAGEMENT

 

 

History of Systems Approach

The easiest way to gain an understanding of the methodology of systems engineering is to understand the historical development of the process. Major characters, but not all, in the development of systems engineering history would be:

Adam Smith - Product-reduction (analysis)

Adam Smith developed the idea that a PRODUCT could be reduced to COMPONENTS (reductionism). The components then could be manufactured cheaply and efficiently by many skilled craftsmen manufacturing just one component each rather than the whole product.

Eli Whitney (LeBlanc) - Product-systems (synthesis)

Eli Whitney viewed a product as a SYSTEM of components or the synthesis of parts, that not only could be manufactured efficiently but also could be repaired and updated after the product system was in use.

Frederick Taylor (Char.Babbage) - Management Science (analysis)

Fredrick Taylor developed the idea that WORK could be reduced to COMPONENTS. Taylor did not believe in using skilled labor since the component tasks to be performed were reduced to the basic motor skills of the average laborer. He developed the concept of the "functional organization" and the science of management.

Lord Louis Mountbatten - Operations Research (synthesis)

Mountbatten was in charge of the operations research team for the invasion of Europe. Although Taylor's concepts worked well for large manufacturing systems, the invasion of Europe required the coordination of disciplines or a management SYSTEM not found in American industry. The result of Mountbatten's efforts was the military planning strategy called combined operations.

Jay Forrester - Systems Dynamics (synthesis of all aspects of systems)

Forrester was one of the early computer designers who came to the realization that computers could be used to model dynamic social and product systems. His work was often used to challenge conventional economic theories by demonstrating unexpected RELATIONSHIPS between components of systems. His ideas led to the development of system modeling and system design on the total system level.

W. Edward Deming - Total Quality Management

Deming carried the systems approach to quality control to Japan and set the world standard for manufacturing quality.

Careful observations of the history of systems analysis will show a repeated cycle of ANALYSIS, or study of the parts, to SYNTHESIS, or studying the affect of the part on the whole. This is the result of two basic philosophies. REDUCTIONISM believed everything could be reduced to simpler components and MECHANISM believed everything is controlled by cause and effect relationships.

The objective of systems engineering is to understand the whole relative to its parts by studying the synthesis of systems.

Systems defined

A SYSTEM is an assemblage of components forming a unity based on the functional relationships between the components.

1. COMPONENTS are the elements of a system. Components can often be divided to smaller elements or components.
2. ATTRIBUTES are the properties or discernible manifestations of the components.
3. RELATIONSHIPS are the mechanistic links between the components and attributes of the components.

Properties of Unity

1. The attributes of any component has an affect on the attributes of the whole system.
2. The attributes of any component depend on the attributes of at least one other component of the system.
3. The components cannot be divided into independent subsystems based on attributes.

These properties ensure that the set of components comprising a system has some overall attribute that cannot be exhibited by any of its subsystems.

Classifications of systems

1. ENVIRONMENT is the total system of the universe.
2. CLOSED SYSTEM is a system that does not interact with or have relationships with the  environment. In most cases these systems are conceptual only.
3. OPEN SYSTEM is a system that interacts with the environment and has relationships and   components, called INPUTS and OUTPUTS, shared with the environment. The shared   relationships define the BOUNDARIES of the system. Open systems often from SUBSYSTEMS of other systems.
4. STATIC SYSTEMS are systems that do not change over time. These systems are often  conceptual or subsystems of larger systems.
5. DYNAMIC SYSTEMS are systems that change over time.
6. NATURAL SYSTEMS are systems that come into being in the natural environment.
7. MAN-MADE SYSTEMS are systems devised by mankind to provide the desired outputs for  the given inputs.

1. FUNCTION is the purposeful attributes of a man-made system.(The buzzers and  whistles we want to see or hear.)
2. ENTROPY consists of the components and relationships of the system that do not contribute to its function. It can be viewed as the unusable functions and components
3. Relationships between components can be classified using the system function.

1. FIRST ORDER relationships are necessary for the system to performs its function.
2. SECOND ORDER relationships are complimentary or add to the system function.
3. REDUNDANT relationships are duplicate relationships present to assure system function.

8. PROCESS (noun) is the cumulative effect of all aspects of a dynamic system over time. This is often further defined as an adjective for a type of systems:
9. PROCESSING SYSTEM is a man-made system consisting of components that ALTER materials, energy, or information.

1. A convenient classification of components is:

1. FLOW COMPONENTS are the material, energy, or information being     altered. Many times the flow components that are both inputs and     outputs are called THROUGHPUTS.
2. STRUCTURAL COMPONENTS are the static components of a system or     any component that is not altered over time.   

2. OPERATING (PROCESSING, ACTIVITY) COMPONENTS are the dynamic components of the system that alter flow components. Operations are often described by their effect on the flow components of the system. In this manner many operations are actual described as functions. As an example, a "baking" operation is actually the operation that changes the attributes of the flow component pie in the structural component oven with flow component heat.

10. PRODUCT-SYSTEM - is a processing system that is related to some commercial product such as a military system and a tank, transportation system and a car, electrical system and a television, information system and a computer. The function of most product-system is to provide a social benefit beyond simply the production of the product.
11. CYBERNETIC SYSTEMS are subsystems that govern a system toward its function. (In natural systems unity is considered its function.)

Describing a systems is often an ART that imposes arbitrary boundaries and assumptions. The greater the success in determining the components and relationships that determine the system function, the better the understanding of the system.

When dealing with systems, some, or all, of the engineering disciplines might play a role. Although most engineering practitioners would prefer to be isolated (closed system) in their particular field, the reality is that an integration is necessary for a successful synthesis of a system.

SYSTEM ENGINEERING MANAGEMENT is the bringing of scientific and engineering talent (people) systematically to bear on the evolution of a man-made system. The effort is accomplished primarily through team building and the systematic integration of multiple disciplines and skills.

For the remainder of this course systems engineering will be limited to the manufacturing disciplines. This will allow for the development of a methodology relative to the PRODUCT-SYSTEM most commonly found in manufacturing. This does not imply that the same approach can not be used for a wider set of system using the principles.

QUESTIONS 1

1. The work of Frederick Taylor was a great contribution to the success of American business. What aspects of the "game", if any, have changed making the classical functional organization, utilizing minimum skill labor, obsolete?

2. Is a clock a system? If so, what are the components, the relationships, and the attributes? Since the clock is man-made, what is the useful attribute or function of the clock? Is the clock an open or closed system, static or dynamic system. If the owner of the clock is included in the system, describe the cybernetic aspects of the total system.

3. You have a battery attached to a light bulb. View the system as a processing system. What are the flow components, the structural components, the inputs, the outputs? What is the process component of the system?

4. Your professor claims that all objects fall toward earth with the same acceleration. You have taken your favorite beach ball and bowling ball to the top of the leaning tower of Pisa to duplicate the original Galileo experiment. Describe the system that your professor is envisioning. Describe the system you are going to experiment with? Will the predicted system attributes be the same? Who is correct and who is wrong?

5. In structural engineering, one approach to analyzing structural systems is called statics. This approach often fails when structures are static indeterminate. From a systems engineers point of view, what type of conceptual system is involved and what type of real world system? How did the boundaries set for the conceptual system fail to provide system unity.

6. You are reading this question on the final exam. As a systems engineer, what are the transformation steps or the engineering process your are going through to answer the question?

7. Systems engineering is often coordinated with team building. What aspects of the systems engineering procedures compliment team organization development?

CASE STUDY 1 - Instant Photography

Eastman Kodak Company attempted to compete with Polaroid in the instant photography market. The Company designed the cameras, produced the film, and set up the marketing organization with the plan of marketing the product for the holiday season of 1976. One month before the product was to be released to the public, Consumer's Guide reported that the color stability of the product was poor. Eastman Kodak pulled its total inventory from the dealers only to find that the the new Polaroid camera filled the market sector created by the Kodak advertising. This mistake cost Eastman Kodak over one billion dollars and the whole instant photography market.

Look at this situation from the systems approach.

ANSWERS 1

1. Taylor believed in Scientific Management or the reduction by management of production systems to the lowest labor components that can be effectively performed by unskilled labor. The idea was the product of 1900s America and now finds difficulty in the 1990s because of:

1. The cheap unskilled immigrant labor of the 1900s that Taylor's system worked well with is no longer available.
2. Customers are demanding quality products rather than commodity products. As a result, Taylor's top down management structure fails to innovate and adapt to the rapidly moving standards required by quality seeking customers.
3. Product liability and social responsibilities have forced manufactures to view a broader picture of their operations.
4. The confrontational situation between labor and management "experts" has proven counter productive.
5. Organizations utilizing Taylor's function lines have become top heavy with redundant staff.

2. The gears are the components and the inter-mesh of the gears are the relationships. The attribute of the clock is the relative positioning of the hands over time. The useful attribute of the clock or its function is the synchronization of the hands with the motion of the earth. The clock, like all systems, is an open system with the winding the input and the motion of the balance wheel the output. If there is an owner using the clock, then the output of the clock is also the information passed to the owner. In this case the owner is also a feedback loop acting as a cybernetic subsystem.

3. The light circuit is a processing system in which the electrons are flow components, the wire, bulb, battery are structural components, and transformation of chemical energy to electron motion and the transformation of electron motion to light are the processes.

4. The professors system is a closed system considering only the balls and the gravitational field of the earth. Your system is an open system including the air resistance. The two systems views will give contradictory attributes. Both people are correct within their definition of the system.

5. The structural analysis approach using statics is too limited a system to provide useful results in the indeterminate world. The best way to check if the static system is a true system is to see if enough relationships exist to define a complete or stable structural system - unit.

6. NEED or what does the guy want? ANALYSIS or what is given in the question? SYNTHESIS or what can I dream up? OPTIMIZATION or which idea will he buy? SPECIFICATION or how can I say this? PRODUCTION or can he read what I am writing? TEST or turn in the exam? EVALUATION or what is my grade?

7. Systems engineering develops the mathematical models and procedures necessary to study complex interrelated problems. Team building develops the organizational and personal skills required to utilize the systems engineering procedures.

PRODUCT-SYSTEM

CONSUMER-TO-CONSUMER PROCESS            

PRODUCT-SYSTEM LIFE-CYCLE               

A. COST ENGINEERING        
B. DESIGN                  
C. MANUFACTURING          
D. SUPPORT                 

SYSTEMS ENGINEER'S INTEGRATED LIFE-CYCLE

A. CONCEPTUAL DESIGN      
B. PRELIMINARY DESIGN    
C. DETAIL DESIGN         
D. PRODUCTION            
E. UTILIZATION AND SUPPORT
F. DISPOSAL               

PRODUCTS VIEWED AS A SYSTEMS

The Consumer-to-Consumer Process

For the course we will concentrate on a type of processing system that we find in most engineering applications, or the PRODUCT-SYSTEM. The first step in studying any system is the definition of the components of the system. One approach is to view a product-system from the limited point of view of the business school by reducing the product "process" to components such as:

The component, when linked by their relationships, form a subsystem called the CONSUMER-TO-CONSUMER PROCESS.

The systems engineer must consider a larger boundary for the PRODUCT-SYSTEMS than the business manager, in other words a product -system must include the product and all processes related to the product over time. Such an approach is dynamic or has a set of components called a "LIFE-CYCLE" relative to TIME.

Different View of the Product-System Life-cycle

One obvious example of the components of a life-cycle is the cost engineer's REVENUE CURVE or the graph of the cash flow generated by a product-system over time.

The cost engineer's point of view of a product-system has components called "phases" defined by MILESTONES such as the "break even point", "payback" or "economic life". Since in most cases the termination of a product-system is set at the economic life when other sources of revenue become more attractive, the economic life for a product-system is often accepted as the end of the product-system life-cycle.

(Note: At a later time we will discuss life-cycle costing or LCC. The LCC procedure is the cost engineer's analysis of the product-system over the phases of the economic life-cycle.)

The cost engineers economic life-cycle is not the only life-cycle system, or SUBSYSTEM, associated with a product-system. There is also a design life-cycle, manufacturing life-cycle, logistic support life-cycle, etc. When these different professional functions are viewed together, the following diagram can be constructed of interrelated (open dynamic) subsystem life-cycles.

From the view of a systems engineer, the many life-cycles must be considered simultaneously in order to TRANSFORM, COORDINATE, and INTEGRATE their components functions as a whole.

Product-system Life Cycle Process

In engineering a product-system, it is often convenient to consider a set of STANDARDIZED life-cycle phases or accepted groupings of processes that most product-system progress through over time. Although many different approached have been formulated for the product-system life-cycle (see illustrations), the formalized structure defined by Blanchard and used extensively is:

1) Design and development

2) Production or construction

3) Operational use and support

(Note: This approach is heavily biased toward the design engineers view of systems and one must continually consider the other interrelated systems.)

Blanchard's structure can be further refined by considering phases between major milestones or reviews within the system life-cycle.

6 images will be added later……………………….

Design and development

CONCEPTUAL PHASE - defining the NEED and FEASIBILITY of a system, its technical performance parameters (TPM), operational requirements (DDP) or MISSION, and support polices. The primary documentation for the phase is the systems specification (A) and the initial program management plans (PMP, SEMP, TEMP).

PRELIMINARY DESIGN PHASE - performing the FUNCTIONAL analysis of the system, EVALUATING different alternative design approaches for the best approach. The primary documents for this phase are the development plan (SEMP), process FAST diagram, and performance specifications (B).

DETAIL DESIGN PHASE - preparing functional design layouts and etc., developing system prototypes, and performing design modifications to correct deficiencies and /or improve design. The primary document out of this phase is the product (C), material (D), and performance specifications (E).

Production or construction

PRODUCTION PHASE - combining operations, materials, and personnel resources in such a manner as to provide the necessary product-system output in an effective and efficient manner.

Operational use and support

UTILIZATION AND SUPPORT PHASE - providing consumer use of the product-system throughout its life-cycle, incorporating product modifications for improvements, and providing logistical support.

PHASE OUT AND DISPOSAL PHASE - disposing or replacing of a product system due to obsolescence or wear.

Within the phases are a series of iterative procedures diagrammed as follows:

Product-System Life-Cycle Process

*Note: the book in places will use these expressions to mean the same thing.

QUESTIONS 2

1. Great emphasis has been placed on the customer-to-customer process. What market conditions today make this approach so important? Does it adequately represent the product-system from the systems engineer's point of view?

2. The driving factor for most product-systems is revenue. What is the expected revenue curve associated with a product-system life-cycle? What are major decision points along the revenue curve. What is the most common definition of the end of the product-system life-cycle?

3. Using your own functional area, describe the product-system life-cycle from your point of view?

4. Every functional discipline within a company has a different concept of the product-system life-cycle. What is the goal of systems engineering when defining the product-system life-cycle?

5. The consumer-to-consumer process has an acquisition phase and utilization phase. Product-system life-cycle is divided into three major phases. What are they? These phases are often divided again for a total of six phases. What are they? What is the motivation for using these phases?

6. Each phase of the system life-cycle are followed by a reporting and approval process. What documentation and results should be expected at the end of each phase?

CASE STUDY 2 - The Weapons Program

The Peter Kiewit Company constructed the Oak Ridge Atomic Facility and most of the Hanford Weapons Facility. From the point of view of the Kiewit Company the facilities were construction projects. From the point of view of the Department of Defense the facilities were weapons systems. From the point of view of the Department of Energy the facilities are clean-up projects. In fact during each "situation" of the facilities life, each governing agency or contractor had total control.

What has been the result of this "situational management style" and how would the product-system life-cycle apply to the atomic project using twenty-twenty hindsight.

Health Care Legislation

The currently proposed national health care legislation will follow a series of planning steps as required by law. It is possible to view these steps in terms of a product-system life-cycle.  

CONCEPTUAL DESIGN PHASE - White house staff study with President's approval

Phase completed with Presidential submittal to Congress

PRELIMINARY DESIGN PHASE - Committee actions in the House and Senate

Phase completed with Committee votes

DETAIL DESIGN PHASE - Debate of full House and Senate

Phase completed with vote of House and Senate

PRODUCTION PHASE - Executive orders in the Executive Branch

Phase completed with approval of the President

USAGE AND SUPPORT - Care administered by health care system

Phase completed with support of public and medical profession

PHASEOUT - Undefined

ANSWERS 2

1. With the focus on quality in todays markets the products must be closely tied to consumer needs. The consumer-to-consumer process is based on this requirement. What the consumer-to-consumer process does not consider is the time element of the product-system that is required for the coordination of the product-system life-cycle.

2. The revenue curve, maintained by the cost engineer, which starts at a loss, reaches a positive return, a payback, and then finally declining to a diminishing return, is usually the driving force in most product-systems. As such, the economic life is considered the termination of most product-systems life-cycles.

3. Discuss.

4. The systems engineer is developing a framework on which to coordinated all subsystems or disciplines involved in the product-system. As such, the phases defined are often inadequate when viewed by any one discipline.

5. The book has been dividing product-systems into smaller and smaller phases. First for the consumer-to-consumer process there was the acquisition phase and utilization phase. Then the design and development phase, production phase, and operational phase. Then the conceptual design phase, preliminary design phase, detail design phase, production phase, utilization phase, and phase out.

6. Discuss. The most common reports are the system specification, program management plan (PMP) for the end of the conceptual phase. The development and performance specification and the systems engineering plan (SEMP) at the end of the preliminary design phase. The product, material, and performance specifications at the end of the detail design phase. The statistical process control SPC reports (Shewart) and cost reports during the production phase. And the cost reports at the phase out.

 

 

CONCEPTUAL DESIGN PHASE

DEFINITION OF NEED

FEASIBILITY STUDY

SYSTEM OPERATIONAL SPECIFICATION

A. OPERATIONAL CONCEPT
B. PRELIMINARY SYSTEM ANALYSIS
C. SYSTEM SPECIFICATION

SYSTEM PLANNING

A. PROGRAM MANAGEMENT PLAN - PMP
B. SYSTEM ENGINEERING MANAGEMENT PLAN - SEMP
C. TEST AND EVALUATION MASTER PLAN - TEMP

CONCEPTUAL DESIGN REVIEW - CDR

CONCEPTUAL DESIGN PHASE

PRELIMINARY DESIGN PHASE

FUNCTIONAL ANALYSIS

A. FUNCTIONAL ANALYSIS SYSTEMS TECHNIQUE - FAST
B. FUNCTIONAL FLOW BLOCK DIAGRAM - FFBD

ALTERNATIVE DEVELOPMENT

A. SCHEMATIC BLOCK DIAGRAM - SBD
B. ALLOCATION OF RESOURCES

OPTIMIZATION AND TRADE-OFFS

A. MODELING
B. VERIFICATION
C. VALIDATION

PRODUCT DEVELOPMENT SPECIFICATION

PRELIMINARY DESIGN REVIEW - PDR

CASE STUDY 4 - Replace Tire Allocation Model

An example of "replace tire" using a mathematical model is the linear goal programming model. Say that the time estimate of "replace tire" is only a target value of 10 minutes. Let the next level down have the target times, costs per unit and minimum times of:

The problem is to refine the allocation of 10 minutes to the next level so as to reduce cost and still perform the same system function.

For the model, define the following symbols:

X₁ = reduction in raising time
X₂ = increase in raising time
X₃ = reduction in removal time
X₄ = increase in removal time
X₅ = reduction in install time
X₆ = increase in install time
X₇ = reduction in lower time
X₈ = increase lower time

then the marginal cost (negative is reduced cost) of the reallocated time is modeled as:

Minimize       12X₁-10X₂+20X₃-5X₄+20X₅-5X₆+5X7-5X₈

subject to:

3-(X₁-X₂) >= 1 raise car time limit
2-(X₃-X₄) >= .5 remove tire time limit
2-(X₅-X₆) >= .5 install tire time limit
3-(X₇-X₈) >= .5 lower car time limit
(3-X₁+X₂)+(2-X₃