Part II Concurrency: Information Management Challenge

1. Part II Concurrency: Information Management Challenge

2. Concurrent Engineering(called also simultaneous or life cycle engineering) is a philosophy that attracts increasing attention of systems science community and systems analysts working in various application areas. CEaddresses the issues of a major technological change from sequential to simultaneous engineering. It requires that system analysts and designers understand how to acquire, process, and integrate information concerning various stages of a life-cycle of a product. It is a systematic approach that enables cooperative work among all groups that plan, design, produce, maintain and support the product over its life cycle. It calls for multidiscipline teamwork and promotes collaboration and application of different skills and knowledge sources.

3. Many definitions of concurrent engineering exist. The main difference is on the topics covered within the definition. The definition that is broadly adopted within CE research community was proposed by The Institute for Defence Analyses in its IDA Report R-338 in 1988: “Concurrent Engineering is a systematic approach to the integrated, concurrent design of products and their related processes, including manufacture and support. This approach is intended to cause the developer from the outset, to consider all elements of the product life cycle from conception through disposal, including quality, cost, schedule and user requirement.”

4. The traditional design philosophy was a result of increased specialisation and departmentalisation in periods of rapid growth after the Second World War. This led to a design process often called “over the wall design”, where the design would be passed over the wall from department to department with little consultation or coordination. The main features of the traditional design philosophy are: • Sequential design process • Specialisation • “Over the wall design” • Limited concept development

5. This approach led to the following problems: • As the work of departments was not integrated, each department would attempt to maximise their own output, not the overall output. • Downstream functions were rarely consulted in the early stages when most of the significant design decisions were being made.

6. Designs would have to be redone or altered as problems were identified by downstream departments. This added greatly to the time required for a design to be completed. • The above problems led to mistrust between departments as products below expectations were produced. • With little consultation between departments misunderstandings are more common and the constraints of other departments are not always known.

7. Apart from the reasons outlined above, there are three primary reasons that require a change from the traditional design process : Rapid pace of technology.Due to increased competition, technology is advancing at an ever faster pace. To maintain market share the use of new technologies is often required. This required designs to be produced at ever quicker rates with increased complexity of design.

8. Forced design cycle compression.With less time designers often attempted to ignore the input from other functions so as to shorten cycle time. This resulted in a situation where problems would have to be addressed later in the development cycle often increasing cycle times and delivering an inferior product. Emerging information technology and methodologies.With the emergence of new tools and techniques, a new design philosophy was required to take full advantage of these advances. Thus a design methodology was required that would reduce development time while considering the input of all relevant functions to the design process. Concurrent Engineering satisfies these criteria.

9. The advantages of concurrent engineering can be delineated in terms of two broad categories: 1. Reduction in product development lead time Concurrent engineering performs the product development activities on a parallel rather than on a sequential basis. This concept can potentially reduce the entire product design cycle time and contribute to significant reduction of duplication of effort and future costly product redesigns. This benefit of concurrent engineering is achieved when an efficient flow of information and communication exists among various decision makers in the early phases of product development. This advantage, in an ultimate sense, contributes to more efficient operation and higher productivity.

10. 2. Overall cost savings Concurrent engineering designs for manufacturability. Process planning activities are streamlined in such a way that total product costs can be reduced. This may be in the form of reduction in the number of parts to be manufactured, better machine utilization time, easier manufacturable parts, lesser reworks and scraps, greater use of standard features resulting in standard tooling and reduced costs, lower changes in process planning due to lower number of part redesigns.

11. INFORMATION FLOW ARCHITECTURE FOR CONCURRENCY EVALUATION Concurrent approach must simultaneously embrace the life cycle and concurrency analysis refers to the integration of various values (concurrency attributes) within the broad scope of acquisition and utilization. This values include not only the main functions of the product but also its aesthetics, manufacturability, assemblability, reliability, serviceability, and so on. System development process should thus incorporate, at its various stages, a number of concurrency attributes. As a consequence, this means that it also undergoes a multicriteria evaluation that is included in the design process as presented in the Figure.

12. Design as a goal-seeking system

13. Sample concurrency attributes

14. Architecture of the proposed system Concurrency agents are associated with concurrency attributes a1, a2, ..., an. Agents cooperate and contribute to the global degree of concurrency satisfaction denoted by F=f(a1, a2, ..., an). The degree of satisfaction of a given concurrency attribute simulates the judgment on how well a system satisfies the requirements associated with the corresponding attribute.

15. An agent can be described as a model of an intelligent entity consisting of information and knowledge which can be structured to perform dedicated computational processes within a more complex system.

16. Each agent consists of two entities. The internal entity addresses the tasks that are assigned to the agent. Tasks refer to design requirements associated with the corresponding concurrency attributes. Internal entity includes the knowledge required to perform the tasks, the inference mechanisms necessary to represent that knowledge, and the means of communication necessary for the agent to act with the outside world. The external entity is a planning one in its nature. It includes the model of the environment in which the agent operates. This model contains the abilities of the given agent as well as other agents present in the system, and relationships between agents. Internal entity performs the tasks that the agent is able to solve itself. The external one acts as an intelligent planner that determines how the tasks may be broken down (if possible and necessary), distributed to other agents, and integrated.

18. Agents are grouped into worlds, and each agent may be a member of many worlds simultaneously. Agents can communicate either directly or indirectly (through other agents), and the mode of communication may differ depending on its importance. Next Figure depicts grouping and links between agents.

19. Communication links and worlds of agents

20. DEDUCTION GRAPHS FOR CONCURRENCY SATISFACTION Introduction to concurrency satisfaction problem Introduction of various life-cycle attributes in various stages of product design is termed concurrency satisfaction. Concurrency set is a collection of attributes (manufacturability, serviceability, etc.) necessary to achieve concurrency.

21. This Chapter discusses an approach to plan an optimal policy to expand concurrency sets in such a way that the desired concurrency level is confidently addressed by a designer during the design process undertaken in a concurrent environment. The presented approach is based on deduction graphs and the optimal concurrency plan is arrived at by applying a 0-1 integer programming technique.

22. For product design, the concurrency attributes usually include the following: a1: aesthetics attribute that considers such design factors as shape, size, colour, finish, texture, styling, and social significance, a2: capacity with such factors as size, force, movement, direction, and speed, a3: disposability influenced by the material factor, a4: durabilitywith design factors of corrosion, humidity, strength, moisture, and abuse, a5: ergonomics with such factors as operating height, operating comfort, lighting, shape compatibility, type of operation, noise, heat, cold, controls, monitoring devices, and human size, a6: interchangeability with factors of rapidity, accuracy, and modules, a7: maintainability with factors of continuous, regular, sporadic, none, ease of inspection, ease of repair, life cycle, ease of part replacement, and availability of parts, a8: marketability influenced by factors of marketing mix, target customers, product differentiation, product quality, product quantity, market share, and price,

23. a9: performance considered with the factors of force, velocity, acceleration, pressure, energy, and handling comfort, a10: transportability described by the factors of lift, orientation, size, packaging, maximum dimensions, maximum weight, and storage, a11: producibility influenced by factors of tolerances, surface, roughness, dimensions, structure, stress, level, geometry, size, height, diameter, space requirements, kinematics, forces, load, deformation, stiffness, elasticity, resonance, energy, pressure, temperature, and operation, a12: reliability with factors of repeatability, measures of availability, duration of downtime, and failures characteristics, a13: safety with noise, stability, illumination, protection systems, operational safety, environmental safety, edges, warning mechanisms, magnetic field, and pinch points, a14: schedulability influenced by factors of flow time, idle time, completion time, delivery dates, capacity, machine utilisation time, a15: serviceability with factors of ease of repair, time to service, and time to respond to service, a16: simplicity considering factors of technology, manufacture, self-maintenance, and use, a17: testability with factors of ease of inspection, built-in tests, and fault characteristics.

24. a11 4.7 3 1 1 4 a3 1 a14 a5 1 2 a1 2.5 1 a16 Directed graph G1 of the sequences of concurrency attributes introduction

25. minz=2.5y(a1,a16)+4.7y(a3,a11)+4y(a3,a14)+y(a3,a16)+3y(a5,a11)+minz=2.5y(a1,a16)+4.7y(a3,a11)+4y(a3,a14)+y(a3,a16)+3y(a5,a11)+ y(a5,a14)+y(a11,a16)+y(a14,a11)+y(a16,a5)+2y(a16,a14) subject to: (i) all y(i,j) and xi are 0-1 integers, (ii) xa5 = xa11 = xa16 = 1, (iii) xa5  y(a16,a5), xa11  y(a3,a11)+y(a14,a11)+y(a5,a11), xa14  y(a3,a14)+y(a16,a14)+y(a5,a14), xa16  y(a1,a16)+y(a3,a16)+y(a11,a16), (iv) xa1  y(a1,a16) 3xa3  y(a3,a11)+ya3,a14)+y(a3,a16), 3xa5  (y(a16,a5))+(y(a5,a14)+y(a5,a11)), 4xa11  (y(a3,a11)+y(a14,a11)+y(a5,a11))+(y(a11,a16)), 4xa14  (y(a5,a14)+y(a16,a14)+y(a3,a14))+(y(a14,a11)), 5xa16  (y(a1,a16)+y(a3,a16)+y(a11,a16))+(y(a16,a14)+y(a16,a5)).

26. By applying any mathematical programming package one can see that the solution to the above is given as: y(a3,a16) = y(a16,a5) = y(a5,a14) = y(a14,a11) = 1. The resulting optimal deduction graph is shown in Figure below. a11 1 a3 1 a14 a5 1 1 a16

27. PLANNING IN CONCURRENT ENVIRONMENT Although CE offers considerable reductions in both time and money as well as increases in product and process quality to an organisation, the maximum benefit is only likely to be attained through focusing on the effective planning of the design process.

28. Product development costs in different phases

29. Blackboard based planning architecture The basis for an intelligent decision support system for design process planning within a Concurrent Engineering (CE) environment is the efficient utilisation and coordination of planning knowledge that resides within computerised workgroups of multidisciplinary experts. A systems approach may be taken to derive, represent and utilise the many models of reasoning that might support a human-centric view of planning in a distributed environment. The blackboard database (BB) provides a suitable framework for utilising these models in a structured manner by representing the planning problem as a loosely coupled hierarchy of partial problems along with the knowledge needed to progressively solve different parts of this problem. This Section discusses such a BB system which is intended to provide the ability to experiment with various control and domain strategies in order to yield insight into more developed and intelligent methods to assist humans in planning the CE design process.

30. Knowledge Sources Knowledge Sources Knowledge Sources Blackboard Database Plan Integration Plan Decomposition Plan Distribution Plan Generation KSAR Control Source Blackboard Database Planning Structure

31. CONCURRENCY IMPLEMENTATION Transition from Sequential to Concurrent Philosophy

32. STEP 0.Obtain the commitment from top management down for a long-term, systems-type outlook for the business as a whole and the design activity in particular. This philosophical realignment must percolate through the entire organisation and embrace a life-cycle view of the company’s products. STEP 1.Inform, train and involve all staff from the very beginning of the implementation process. STEP 2.Review current company systems, and design methods. Take the opportunity of discarding worthless procedures and integrating useful ones. STEP 3.Plan and set goals based on the CE objectives. STEP 4.Implement design teams with emphasis on DFX. STEP 5.Upgrade support infrastructure, in particular computers, databases and communications in consultation with the design teams. STEP 6.Introduce concurrency. STEP 7.Monitor and review progress, not just in activity but also in time. Compare to the formal plans of Step Three and to other similar companies.

33. Implementing concurrency for environmental protection Clearly, environmental protection today has to deal with enormous challenges and issues related to our real and virtual environments characterised mainly by uncertainties, dangerous changes, hazardous materials, contamination, imprecision, and novelty of internet just to name a few. Engineering, operations research, management science and information technologies race to help people to use scientific processes to preserve the quality of human life in such environments. Concurrent engineering philosophy seems to be one of the leaders in this spectacularly exciting race to help to create a better environmental future for our planet.

34. In a wholesome view of a product's life cycle, clear objectives, including potential environmental impact, are necessary at the conceptual stage. To prevent and correct environmental impact life cycle analysis must act hand in hand with good decision making at the design stage of a product. Hence, a new design paradigm arises: Design for Environment (DfE). There are three main goals to DfE: • Minimise the use of non-renewable sources. • Effectively manage renewable resources. • Minimise toxic releases to the environment.

35. In terms of practical aims this means designing to minimise environmental affects. That is, to design products whilst considering the following environmental attributes: Ease of Disassembly Ease of Reuseability Ease of Recyclability Ease of Remanufacturing Durability Maintainability Energy Consumption Product Take Back

36. Ease of Disassembly. • Design for Disassembly (DfD) There are a number of principles that can be followed to ensure ease of disassembly. These include: • Consolidate parts and minimise the number of components:. • Reduce the number of assembly operations: • Avoid chemical bonds: • Try to avoid composite materials: • Use quick release snap fittings wherever possible: • Eliminate or avoid secondary coatings, finishes and platings:

37. Energy Consumption. The less energy a product requires throughout its life cycle the better the product is for the environment. Energy consumed by equipment and appliances is a major source of greenhouse gas emissions. For example, these emissions are responsible for more than a quarter of net greenhouse gas emissions in Australia (excluding land use change and forestry). Consequently, improved energy efficiency of appliances and equipment is a key objective for DfE.

38. Product Take Back. In the future it seems likely that manufacturers will become responsible for the ultimate disposal of their product. To some extent this is already occurring in today’s industry. In Europe, car manufacturers are investigating methods for recycling scrap automobiles. Strict environmental recovery laws (proposed, but not yet implemented) coupled with declining landfill space have caused European car manufacturers to take a new look at recycling, their contributions to the process and ultimate responsibility for its implementation.

39. BMW has opened a pilot recycling plant in Landshut, Germany, to determine just what it will take to dismantle its vehicles and recover their materials on a large scale basis. The company plans to use the information it gains from the Landshut program to ease the disassembly and recovery of future BMW automobiles, and pinpoint environmentally friendly materials.

40. In trying to generalise, the following suggestions may help to ensure that industries in any place in the world become more environmentally conscious: • Increase the landfill costs • Promote the cost savings of DfE • Provide tax benefits for Environmental Products • Educate people • Promote increased durability • Legislate product labelling • Review Restrictions • Government Projects