A Systems Engineering Environment for Integrated Building Design

Abstract

Integrated building design concerns the whole building systems approach. This approach is based on a design support for the building life cycle, in which multiple disciplines and apparently unrelated aspects of design are integrated in a way to allow synergistic benefits to be realized successfully. In order to cope with factors related to tightening environmental requirements, reducing development cycle times and growing complexity, this paper aims to describe a comprehensive design framework vision for integrated building design. A more focused use of applying systems engineering approach to the building design support is presented in response to the ever-increasing complexity of buildings. In particular, this paper addresses all issues of interrelated dynamic optimisation, as local optimisations do not give a global optimisation. The paradigm used, here is to extend and particularly to adapt the work carried out in military and space systems to modern building services by taking into account the semantics of buildings in terms of different engineering fields and architecture issues. INTRODUCTION The systems engineering approach was primarily developed by the military industries as a process by which large engineering projects could be designed, implemented, and tested prior to deployment (Defense Systems Management College, 1990). This approach is based on a structured method towards specification, design, acquisition, integration, reengineering, and implementation of a complex system over its life cycle. Systems engineering (SE) has emerged as a distinct professional discipline since the late nineties in response to the everincreasing complexity of new products and systems of different fields. Eventually, this emergent discipline has been applied with success mainly to scale complex systems and projects in the following industries: aeronautic (e.g. won et al. 2001), automobile (Loureiro et al. 1999) and space (Shishko, 1995), etc. For the building domain, there is a great interest in applying such a good practice in the building design process and particularly manufacturing and production systems. In this case, real design projects typically require the systems-level cooperation of experts from several engineering disciplines. Nowadays systems-level considerations are recognized as being paramount in designing new product. In consequence, systems engineering is an interdisciplinary method that develops and exploits structured efficient approaches to analysis and design complex engineering problems. This focuses more on constructs of analysis and synthesis for problems involving multiple realistic aspects to enable the realization of successful products. Since systems engineering deals with the methodology rather than physical manifestations of science, its description considers both the business and the technical needs of customers with the goal of providing a quality product that meets the user needs. Therefore, Systems engineering covers a broad set of processes and methods for modelling and analyzing interactions among the requirements, subsystems, constraints and components that make up a product. Its purpose is to improve an organization’s understanding of the product as a whole, and to use that total product understanding to better optimize the tradeoffs that drive detailed design, manufacturing, service decisions and so on throughout the product lifecycle. However, the following aspects of real time specification, for instance, have still not properly been addressed in existing building design methods such as: 1. Transformation of an operational need into a description of system performance parameters and a system configuration through the use of an iterative process of evaluation aspects 2. Integration of related technical parameters and ensure compatibility of all related, functional and program interfaces in a manner that optimizes the total system definition and design. 3. Integration of reliability, maintainability, safety, survivability, human and other such factors into the total technical engineering effort to meet cost, schedule and technical performance objectives. This paper deals with a tentative application of systems engineering (SE) concepts to the building design process. As SE is an open process, a major advantage for this application could be a proposed approach with various technologies, business and management aspects that could be efficiently evaluated. This is advantageous because an open process can be applicable to any application domain, as long as these applications adhere to fundamental principles. SE standards have been preliminary successful because their concepts involve new technologies and requirements management means needed for: Definition of systems, including identification of costumer requirements and technological specifications; Development of systems, including conceptual architecture, trade-off of design concepts, configuration management during design development, and integrated product and process development; Deployment of systems, including operational test and evaluation, maintenance over extended lifecycle and reengineering (renovation). Modern systems engineering, including both products and services, is often very knowledge intensive. In accordance with systems engineering, EIA-632 standard (EIA-632, 1998) a method for adapting the process of such a standard to the conceptual architecture for a building design is applied with implementation and evaluation of different phases defined in design process. As a result, building performance specifications, preliminary/detail designs, building prototype build, components tests and subsystem/system integration tests are conducted in sequence to apply the SE concepts to the building design process. A design development process can follow a systems engineering standard or a specific framework in sequence to realise successful integrated building design. Systems engineering is a generic term that describes the application of structured engineering methodologies to the design and creation of complex systems, like building. The remainder of this paper is organized as follows: the next section describes building design process. Then it follows systems engineering and deployment. This is followed by an application of systems engineering to building design process, and finally conclusion. BUILDING DESIGN PROCESS Building design process is the acquisition of a system as an end product. The process begins with the necessity of a building requested by the customer. The process begins with a feasibility study. Financial budget, site conditions, compulsory regulations, clients needs together with the design requirements are defined during the feasibility search. The architectural program is structured at the end of feasibility. During development of architectural program, the issues that affect the design together with architectural aspects (building type, spatial requirements, etc.), environmental aspects (site, location, surroundings, climatic conditions, etc.), and regular aspects (codes and standards) are also taken into account. All-previous steps are considered as the pre-design phase. In other industries, including building construction, design plays an essential role in the efficiency of productive process and in the production of value to the clients (Fabricio et al. 1999). The design process may be divided into a few stages based on the level that each stage is expected. Nevertheless, whatever the stages are; at the end, the output includes the specification documents that satisfy all the requirements needed for design and construction. Based on this information, construction process executes till the building acquired. During the life cycle of the building in use, the feedback for maintenance and renovations are used for the expected modifications in daily necessities. The process is continuously cycling and never ends but feeds the new requirements for a new design problem and starts from scratch. Furthermore, each stage in the process is nonlinear and has feedback cycles, which strengthen the whole process with minimum uncertainty at the end product. Figure 1 shows the schematic illustration of the building design process with its different phases. Figure 1. Building design process In most cases, design process can be simplified as the function of the inputs, limitations, methodologies and outputs. Methodologies describe how to execute the process. In the building design process, the inputs can be outlined as ideas and necessities, and the outputs as products (usually buildings. It is shown in figure 2, that design process might be conducted of limitations relating to regulations, client’s needs, cost, and time; and of methodologies in form of organizations, tools and techniques. Figure 2. Simplified elements of building design process For instance, Fabricio (et al., 1999) mentioned an important perspective on building. This has the purpose of characterizing the design process as a sequential conversion view that transforms the information from technical standards and requirements into solutions and product specifications. SYSTEM ENGINEERING AND DEPLOYMENT The efficiency of SE concepts is defined by methods, algorithms and tools used in the most complex of design problems. This methodology includes elements such as systems response functions, trade-off analysis, specifications and performance metrics, optimization techniques in the presence of various sorts of constraints, marginal and sensibility analysis, utility theory, scheduling, control databases, cost estimation, decision analysis, modelling and simulation, and software environments and tools. Although, SE model is an interdisciplinary area in which its conception affects all kinds of projects, a good description of systems engineering applies to systems as simple as a toaster and as complex as environmental restoration. The only difference between these two extremes is the degree of formality with which each process is used. Consequently, a model of systems engineering is a diagram that includes the known processes that we do. However, there are many models of popular systems engineering standards, such as: ISO-15288, ANSI/EIA-632, IEEE-1220, SP-6105, ECSS-E-10A, but their diagrams are similar to each other (Sheard et al. 1998). The EIA-632 standard is chosen, in this paper as an appropriate model for building design process; because it has an extra phase that involves the aggregation of end products. Technical Management Process – Processes that plan, assess, and control the systems engineering process. GUIDE TO THE APPLICATION OF THE SYSTEMS ENGINEERING Systems engineering and processes. The SE Framework Multidisciplinary teamwork ensures the accuracy and completeness of the evolving technical data package from which test articles, pre-production prototypes, and production products are to be manufactured or coded. Systems of systems. The deployment of SE product can be carried out in a comprehensive approach by separating the final product (the building) from the enabling product (production systems: crane, etc.) and development product (simulation tools, etc.) this can be best illustrated by the following figure 3. A single bloc k will really define the complete solution to a complex problem more typical of the design project. When an end product sub-system requires further development it will have its own subordinate building block. Once the descriptions of the end product of the initial building block are completed, and preliminary descriptions of the end product subsystems are defined, the development of the next lower layer of building block can be initiated. If the building block has reached the “button”, the design of these items requires nodevelopment (i.e. all enabling product for that end product already exist and are all compatible with each other and with total solution).

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Cite this paper

@inproceedings{Yahiaoui2006ASE, title={A Systems Engineering Environment for Integrated Building Design}, author={Azzedine Yahiaoui and Abd-El-Kader Sahraoui and Jan L. M. Hensen and Paul W. P. de Brouwer and Arthur van Schendeistraat}, year={2006} }