Using Industrial Hydraulics |
Applications of Computer-Aided Manufacturing
Most of the systems presented in this guide involve energy consumption. As North American society has moved from its early reliance on renew able energy sources (wind, water, and horse power) to today's seemingly endless addiction to nonrenewable fossil fuels, it has also added vastly to its population and increased its per capita energy use.
The resulting environmental degradation (primarily evident in air and water quality) has spurred efforts to reverse this decline. Governmental regulations are a part of such efforts, but this guide emphasizes the investigation of alternative fuels and design approaches that go beyond those minimally accept able to society. Designers are encouraged to take a leadership role in mitigating environmental degradations.
On this note, it is becoming increasingly clear that global warming is well under way. It may be less clear to what precise extent our hugely increased carbon-based energy consumption is responsible, with its associated heat release and gaseous additions to the atmosphere. But it is very clear that the world's supply of fossil fuel is diminishing, with future consequences for all buildings (and their occupants) that today rely so thoroughly on nonrenewable energy sources.
The buildings of today contribute to negative global consequences that will impact future generations, and our approach to mechanical and electrical systems must consider how best to minimize and mitigate-if not negate-such negative environmental impacts. Thus, on-site resources--daylighting, passive solar heating, passive cooling, solar water heating, rainwater, wastewater treatment, photovoltaic electricity--share the spot light with traditional off-site resources (natural gas, oil, the electrical grid, water and sewer lines). On-site processes can be area-intensive and labor intensive and can involve increased first costs that require years to recover through savings in energy, water, and/or material consumption. Off-site processes are usually subsidized by society, often with substantial environmental costs. On-site energy use requires us to look beyond the building, to pay as much attention to a building's context as to the mechanical and electrical spaces, equipment, and systems within.
Throughout the many editions of this guide, another trend has emerged. Society has slowly moved from systems that centralize the provision of heating, cooling, water, and electricity toward those that encourage more localized production and control. Increased sophistication of digital control systems has encouraged this trend. Further encouragement comes from multipurpose buildings whose schedules of occupancy are fragmented and from corporations with varying work schedules that result in partial occupancy on weekends. Another factor in this move to decentralization is worker satisfaction; there is increasingly solid evidence that productivity increases with a sense of individual control of one's work environment. Residences are commonly being used as office work environments.
Expanding communications networks have made this possible. As residential designs thus become more complex (with office-quality lighting, zones for heating/cooling, sophisticated communications, noise control), our nonresidential work environments become more attractive and individual.
Air and water pollution problems stemming from buildings (and their systems and occupants) are widely recognized and generally condemned.
A rapidly increasing interest in green design on the part of clients and designers may help to mitigate such problems, although green design is hopefully just an intermediate step in the journey to truly sustainable solutions.
Another pervasive pollutant affecting our quality of life is noise. Noise impacts building siting, space planning, exterior and interior material selections-even the choice of cooling systems (as with natural ventilation). Air and water pollution can result in physical illness, but so can noise pollution, along with its burden of mental stress.
This guide is written primarily for the North American building design community and has always emphasized examples from this region. Yet other areas of the world, some with similar traditions and fuel sources, have worthy examples of new strategies for building design utilizing on-site energy and energy conservation. Thus, some buildings from Europe and Asia appear in this guide, along with many North American examples.
Listings of such buildings (and associated researchers and designers) have been included in the index of this edition.
Building system design is now widely under taken using computers, often through proprietary software that includes hundreds of built-in assumptions. This guide encourages the designer to take a rational approach to system design: to verify intuitive design moves and assumptions and to use computers as tools to facilitate such verification, but to use patterns and approximations to point early design efforts in the right direction. Hand calculations have the added benefit of exposing all pertinent variables and assumptions to the designer.
This in itself is a valuable rationale for conducting some portion of an analysis manually. Rough hand-calculated results should point in the same direction as results obtained with a computer; the greater the disparity, the greater the need to check both approaches. This is not to disparage the use of simulations, which are valuable (if not indispensable) in optimizing complex and sometimes counterintuitive systems.
This guide is developed with the student, the architect- or engineer-in-training, and the practicing professional in mind. Basic theory, preliminary design guidelines, and detailed design procedures allow the guide to serve both as an introductory text for the student and as a more advanced reference for both professional and student. This work is intended to be used as a guide for a range of courses in architecture, architectural engineering, and building/construction management.
This guide serves as a reference for architectural registration examinees in the United States and Canada. We also hope to have provided a useful reference guide for the offices of architects, engineers, construction managers, and other building professionals.