Systems Engineering. Engineering 101 By Virgilio Gonzalez

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1 Systems Engineering Engineering 101 By Virgilio Gonzalez

2 Systems process

3 What is a System? What is your definition? A system is a construct or collection of different elements that together produce results not obtainable by the elements alone. The elements, or parts, can include people, hardware, software, facilities, policies, and documents; that is, all things required to produce systems-level results. The results include system level qualities, properties, characteristics, functions, behavior and performance. The value added by the system as a whole, beyond that contributed independently by the parts, is primarily created by the relationship among the parts; that is, how they are interconnected.

4 What is Systems Engineering? What is your definition? Systems Engineering is an engineering discipline whose responsibility is creating and executing an interdisciplinary process to ensure that the customer and stakeholder's needs are satisfied in a high quality, trustworthy, cost efficient and schedule compliant manner throughout a system's entire life cycle. This process is usually comprised of the following seven tasks: State the problem, Investigate alternatives, Model the system, Integrate, Launch the system, Assess performance, and Re-evaluate. These functions can be summarized with the acronym SIMILAR: State, Investigate, Model, Integrate, Launch, Assess and Re-evaluate. It is important to note that the Systems Engineering Process is not sequential. The functions are performed in a parallel and iterative manner.

5 Systems Engineering Process

6 State the problem Most critical step! Describe the top-level functions that the system must perform Examples are mission statements, a concept of operations or a description of the deficiency that must be ameliorated. Identify requirements that should be traceable to this problem statement. Functional requirements answer the question What must be done? Performance requirements answer the question How well? e.g. speed, weight, time, restrictions, regulations, etc. Acceptable systems must satisfy all the mandatory requirements and may need to do trade-offs between other lower priority. The requirements should be traced to the person or reason to be included. Used to negotiate changes in case of trade-offs. The problem statement should be in terms of what must be done, not how to do it. The problem statement should express the customer requirements in functional or behavioral terms. E.g. The system X must perform the function Y within the parameters Z and satisfying the regulation W Inputs come from end users, operators, maintainers, suppliers, acquirers, owners, regulatory agencies, victims, sponsors, manufacturers and other stakeholders.

7 Investigate Alternatives Propose alternative designs Different options are created and evaluated based on performance, schedule, cost and risk figures of merit. No design is likely to be best on all figures of merit This analysis should be redone whenever more data are available. Start with estimates by the design engineers. Construct and evaluate several models Run tests on the real system. Alternatives should be judged for compliance of capability against requirements..

8 Model the system Develop models for most alternative designs. The model for the preferred alternative will be expanded and used to help manage the system throughout its entire life cycle. Models can be physical analogs, analytic equations, state machines, block diagrams, functional flow diagrams, objectoriented models, computer simulations and mental models. Systems Engineering is responsible for creating a product and also a process for producing it. Models should be constructed for both the product and the process. The Systems Engineering Process is not sequential: it is parallel and iterative. Models must be created before alternatives can be investigated.

9 Integrate Integration means bringing things together so they work as a whole. Interfaces between subsystems must be designed. Subsystems should be defined along natural boundaries. Subsystems should be defined to minimize the amount of information to be exchanged between the subsystems. Well-designed subsystems send finished products to other subsystems.

10 Launch the system Launching the system means running the system and producing outputs. It also means allowing the system do what it was intended to do. This is the phase where the preferred alternative is designed in detail The parts are built or bought (Component of-the-shelf). The parts are integrated and tested at various levels leading to the certified product. In parallel, the processes necessary for this are developed where necessary - and applied so that the product can be produced. The requirements should be validated (Are we building the right system?) and verified (Are we building the system right?).

11 Assess performance Figures of merit are used to quantify requirements in the tradeoff studies. They usually focus on the product. Technical performance measures are used to mitigate risk during design and manufacturing. Metrics are used to help manage a company's processes. Measurement is the key. If you cannot measure it, you cannot control it. If you cannot control it, you cannot improve it. Important resources such as weight, volume, price, communications bandwidth and power consumption should be managed. Each subsystem is allocated a portion of the total budget and the project manger is allocated a reserve. These resource budgets are managed throughout the system life cycle.

12 Re-evaluate Re-evaluate means observing outputs and using this information to modify the system, the inputs, the product or the process. Re-evaluate is arguably the most important of these functions. Re-evaluation should be a continual process with many parallel loops. The particular loops that are used depend on the particular problem being solved.

13 References The International Council of Systems Engineering (INCOSE) is the main professional organization in the field. Most of the definitions can be found in the A Consensus of the INCOSE Fellows document A more detailed document can be found in What Is Systems Engineering? A Consensus of Senior Systems Engineers

14 Project Management

15 Project Management Techniques to ensure the quality of the project completion within the planned time, budget and constraints. There are specific goals (satisfy the requirements). A project is a temporary endeavor with a defined beginning and end, usually time constrained Constrained by resources, budget, people, regulations, etc. The primary concern of project management techniques is to achieve the goals within the constraints. Secondary purpose is to optimize the allocation of resources. A project has a limited lifetime while the regular business process are repeated on an ongoing basis. Link:

16 Project Management Triangle SCOPE COST QUALITY TIME

17 Models A Project is typically divided into several hierarchical stages, and each step must be completed before the next. Model 1: Initiation, planning & design, execution & construction, monitoring & control, completion. Model 2: Requirements, Design, Implementation, Verification, Maintenance. Other Models: PROMPT, PRINCE, PRINCE2, PRiSM, CCPM, PERT, etc. Understand your planning methodology and agree with all the participants!

18 Work Breakdown Structure (WBS) Purpose is to divide and conquer Break the system into Functions ( the WHAT that must be done). The function breakdown can be done in many ways. This depends on the disciplines, the company, regulations, etc. Example: Phone manufacturing, support, testing, sales, etc. Each function is broken down into sub-functions (phone imaging, sound, transmission, etc.) Functions are associated with the architecture Architecture is the structure (the How it is done) For example circuit schematics, flow diagrams, etc. The architecture associates an element (e.g. a speaker and microphone), with a function (e.g. Sound), Each activity is a TASK that must be completed with limited time and resources.

19 GANTT Chart Identifies TASKS with times and dependence Lists them in a calendar and adds arrows to graphically show the relation Highlight the tasks that form the Critical Path where a task delay impact the entire project. Tools: MS Project, Primavera and many others

20 Project Management tool example

21 Method The methodology proposed is inspired by the use of project management (PM) tools from operations research. The advising process could be enhanced by modeling academic programs as complex projects that require constant management to be completed on time. A complex project requires two phases, planning and execution. The planning phase establishes a series of major tasks and continues breaking them into smaller parts. The next step identifies dependencies among the tasks creating the critical path where the two major constraints are time and resources required. The Critical Path Method (CPM) is used to identify the vital chain of events to finish a project. The Program Evaluation and Review Technique (PERT) were developed to expand CPM capabilities by using a probabilistic model.

22 Method (continued ) The execution phase of project management monitors the progress of each task and the use of resources. Failed tasks, delays or resource constraints affect the planned execution. Several techniques help in the task allocation when the events deviate from the original plan. Changes to resource allocations, task sequences or even task repetitions can be done when the execution is already in progress. Historical data collected in this process will be used in future cycles to generate better plans. The student workload can be modeled as project resources with limited availability (credits hours).

23 Course Sequences The critical path and time required to finish the program curriculum can be estimated using the CPM and PERT methods. Students will be advised better to allocate limited resources and finish the program in the shortest time possible. Example shows two parallel sequences that converge at the end: The Critical Path Method (CPM) only indicates the minimum time sequence. The PERT method assumes Optimist, Pessimist and Average durations. The model generates a Gamma probability distribution. Critical Path Cours e 1 Cours e 2 Cours e 3 Cours e 6 6 mons 8 mons 18 mons 6 mons 10 mons 18 mons 6 mons 7 mons 18 mons 6 mons 8 mons 18 mons 01/03/07 01/03/07 01/03/07 07/02/07 08/31/07 06/30/08 01/02/08 06/30/08 12/26/09 06/30/08 01/30/09 06/19/11 07/02/07 08/31/07 06/30/08 01/02/08 06/30/08 12/26/09 06/30/08 01/30/09 06/19/11 12/31/08 09/27/09 12/10/12 Non-critical path Optimist Duration Likely Duration Pessimist Duration Cours e 4 6 mons 7 mons 18 mons 07/02/07 08/31/07 06/30/08 Cours e 5 6 mons 9 mons 18 mons 01/02/08 04/01/08 12/26/09 Optimist Finish Likely Finish Pessimist Finish 01/02/08 04/01/08 12/26/09 06/30/08 12/31/08 06/19/11

24 Course Sequence Gantt Chart Same courses represented as Gantt Charts ID Task Name Opt Dur Opt Start Opt Fini sh Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 1 Course 1 6 mons 01/03/07 07/02/07 2 Course 2 6 mons 07/02/07 01/02/08 3 Course 3 6 mons 01/02/08 06/30/08 4 Course 4 6 mons 07/02/07 01/02/08 5 Course 5 6 mons 01/02/08 06/30/08 6 Course 6 6 mons 06/30/08 12/31/08 ID Task Name Duration Start Fi nish Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 1 Course mons 01/03/07 10/10/07 2 Course mons 10/10/07 08/29/08 3 Course mons 08/29/08 05/20/09 4 Course mons 10/10/07 06/30/08 5 Course 5 10 mons 06/30/08 04/30/09 6 Course mons 05/20/09 02/24/10 ID Task Name Pes Dur Pes Start Pes Fini sh H1 H2 H1 H2 H1 H2 H1 H2 H1 H2 H1 H2 H1 H2 H1 H2 H1 H2 H1 H2 H1 1 Course 1 18 mons 01/03/07 06/30/08 2 Course 2 18 mons 06/30/08 12/26/09 3 Course 3 18 mons 12/26/09 06/19/11 4 Course 4 18 mons 06/30/08 12/26/09 5 Course 5 18 mons 12/26/09 06/19/11 Engineering 6 Course 6101 UTEP 18 mons Summer 06/19/ /10/12 Optimist Duration Likely Duration Pessimist Duration

25 CPM and PERT Issues There are different dependencies between courses that must be mapped correctly. For example prerequisites, corequisites, concurrent classes, special calendars, etc. CPM produces only ideal models. PERT highlights the courses that are more likely to impact the program, however it need statistics to feed the model. Electives have different requirements, thus they need to be included as different scenarios. This portion of the tool only considers time constraints.

26 Workload Problem The official degree plan assumes that students will take between 12 to 17 credit hours per semester. (Typical lecture is 3 cr-hr). Many students can only afford to take the minimum full time load of 12 credits per semester. Wrong decisions by the student or the advisor could further delay the graduation. Additionally most students take credits at the community college, out of our control. Failed courses produce additional sequence problems.

27 Example of Unbalanced Load ID Task Name Start Finish Resource Names 1 Course 1 (3Cr) Mon 01/01/07 Mon 10/08/07 Credit 2[300%] 2 Course 2 (3Cr) Mon 10/08/07 Wed 08/27/08 Credit 2[300%] 3 Course 3 (3Cr) Wed 08/27/08 Mon 05/18/09 Credit 2[300%] 4 Course 4 (4Cr) Mon 10/08/07 Sat 06/28/08 Credit 2[400%] 5 Course 5 (2Cr) Sat 06/28/08 Tue 04/28/09 Credit 2[200%] 6 Course 6 (3Cr) Mon 05/18/09 Mon 02/22/10 Credit 2[300%] 700% Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Credit 2[300%] Credit 2[300%] Credit 2[400%] Credit 2[300%] Credit 2[200%] Credit 2[300%] H1 H2 H1 H2 H1 H2 H1 H2 H1 H2 H1 600% 500% 400% 300% 200% 100% Peak Units: 300% 700% 700% 500% 500% 300% 300% Credit 2 Overallocated: Allocated:

28 Example of Balanced Load ID Task Name Start Finish Resource Names 1 Course 1 (3Cr) Mon 01/01/07 Mon 10/08/07 Credit 2[300%] 2 Course 2 (3Cr) Sat 06/28/08 Mon 05/18/09 Credit 2[300%] 3 Course 3 (3Cr) Mon 05/18/09 Tue 02/02/10 Credit 2[300%] 4 Course 4 (4Cr) Mon 10/08/07 Sat 06/28/08 Credit 2[400%] 5 Course 5 (2Cr) Sat 06/28/08 Tue 04/28/09 Credit 2[200%] 6 Course 6 (3Cr) Tue 02/02/10 Tue 11/09/10 Credit 2[300%] Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Credit 2[300%] Credit 2[400%] Credit 2[300%] Credit 2[200%] Credit 2[300%] Credit 2[300%] 600% H1 H2 H1 H2 H1 H2 H1 H2 H1 H2 H1 500% 400% 300% 200% 100% Peak Units: 300% 400% 500% 500% 500% 300% 300% 300% Credit 2 Overallocated: Allocated:

29 Load Balancing Issues Beside the number of credits there are other constraints such as special calendars (e.g. a course offered only on specific semesters). The tools attempts to adjust to the given constraints. If the constraints aren t real then they will produce unnecessary delays. (e.g. inappropriate scheduling of courses). Model does not consider waivers. If a student takes a course out of the normal sequence then a manual adjustment must be made.

30 Full ECE Curriculum presented as CPM Freshm en ID: 1 P re : S ophomore ID: 17 P re : Junior ID: 30 P re : S enior ID: 41 P re : MATH 3323 ID: 27 P re : 1 4 EE 4195 ID: 44 P re : 3 0 UNIV ID: 6 P re : E NGL 1312 ID: 8 P re : 7 PHYS 3325 ID: 31 P re : 2 1 EE 3329 ID: 42 P re : 3 6, 3 1 E NGL 1311 ID: 7 P re : COMM 1302 ID: 9 P re : 7 CHE M 1306 ID: 11 P re : 1 0 EE 3321 ID: 36 P re : 2 9 EE 3353 ID: 39 P re : 3 3 CHE M 1305 ID: 10 P re : MATH 1411 ID: 12 P re : SS PHYS 2420 ID: 13 P re : 1 2 SS MATH 1312 ID: 14 P re : 1 2 SS MATH 2313 ID: 25 P re : 1 4 MATH 2326 EE 3138 ID: 35 P re : 3 3 SS SS EE 3384 ID: 40 P re : 3 3 EE 4220 ID: 45 P re : 3 7, 3 8, EE 4230 ID: 46 P re : 4 5 ID: 26 P re : 1 4 EE 1305 ID: 15 P re : PHYS 2421 ID: 21 P re : 1 4 SS SS EE 3438 ID: 33 P re : 2 9 EE 3340 ID: 38 P re : 3 3 SS EE 1105 EE 3176 HUMN ID: 18 P re : ID: 16 P re : 1 5 EE 2351 ID: 29 P re : 2 8 SS, 2 ID: 34 P re : 3 7 SS POLS 2310 SS EE 4142 ID: 19 P re : EE 2151 ID: 28 P re : 1 6 SS ID: 48 P re : 4 7 SS SS POLS 2311 ID: 20 P re : EE 2369 EE 3376 EE 4342 ID: 47 P re : 3 7 ART ID: 2 P re : ID: 22 P re : 1 5 SS ID: 37 P re : 2 9, 2 2, EE 4378 ID: 50 P re : 3 7 EE 2169 E CON 1301 ID: 3 P re : ID: 23 P re : 2 2 SS EE 3109 ID: 32 P re : 2 2, 2 9 SS HIS T 1301 ID: 4 P re : EE 4178 ID: 51 P re : 5 0 SS HIS T 1302 ID: 5 P re : EE 2372 ID: 24 P re : 1 5 EE 3372 ID: 43 P re : 2 4, 3 7, EE 4374 ID: 49 P re : 4 3

Ideal ECE course sequence by CPM without load restrictions Completion in 7 semesters. Unrealistic peak load of 39 credits on the first semester.

31 Ideal ECE course sequence by CPM without load restrictions Completion in 7 semesters. Unrealistic peak load of 39 credits on the first semester. 4,000% H2 H1 H2 H1 H2 H1 H2 H1 3,500% 3,000% 2,500% 2,000% 1,500% 1,000% 500% Peak Units: 3,900% 2,600% 1,600% 2,300% 2,300% 600% 200% Credit Overallocated: Allocated:

ECE program balanced (18cr) Completion in 8 semesters 1,800% 2006 2007 2008 2009 H2 H1 H2 H1 H2 H1 H2 H1 H2 1,600% 1,400%

32 ECE program balanced (18cr) Completion in 8 semesters 1,800% H2 H1 H2 H1 H2 H1 H2 H1 H2 1,600% 1,400% 1,200% 1,000% 800% 600% 400% 200% Peak Units: 1,800% 1,700% 1,600% 1,800% 1,800% 1,800% 1,700% 500% Credit Overallocated: Allocated:

ECE program balanced (12cr) Completion in 11 semesters 1,200% 2006 2007 2008 2009 2010 2011 H2 H1 H2 H1 H2 H1 H2 H1 H2 H1 H2 H1 H2 1,000%

33 ECE program balanced (12cr) Completion in 11 semesters 1,200% H2 H1 H2 H1 H2 H1 H2 H1 H2 H1 H2 H1 H2 1,000% 800% 600% 400% 200% Peak Units: 1,200% 1,100% 1,200% 1,200% 1,200% 1,200% 1,200% 1,200% 1,200% 1,200% 1,000% Credit Overallocated: Allocated:

Project planning and creating a WBS

37E01500 Project Management and Consulting Practice Project planning and creating a WBS Matti Rossi Lecture 3, Tue 28.2.2017 Learning objectives Describe the project time management planning tasks, and