sábado, 30 de abril de 2011

Aircraft Structures

Aircraft Structures


by: David J. Peery

Aircraft Structures  library.nu #272674

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submitted by: anonymous


0070491968

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year: 1982
pages: 471
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It seems its sencond edition here.

As the following information maybe useful:

The longevity of the original Peery text (1950) is due in part to its fundamental excellence and to limited progress in aircraft structures, such as it was in a 30-year period marked by preoccupation with space and severely retrenched research and development activity. Nevertheless, after three decades, a suitably revised and extended book would appear to have merit, particularly with regard to topics that bear on the design of aircraft structures to reflect improved structural efficiency and reliability.

Publicity accompanying the text makes the claim that the new edition has been brought completely up-to-date. Unfortunately, such is not the case in substance. New material is included indeed; however, it extends in independent chapters only to elasticity of structures, the finite element stiffness method, and thermal stresses.

New material added within existing chapters is relatively limited and more informative in nature than utilitarian. Including the three new chapters, the second edition of twelve chapters replaces the first-edition of eighteen chapters, either by reorganization or elimination of original material. Except for the three new chapter coverages added, the major portion of the first-edition text has simply been reset and the origina figures redrawn, although to larger scale. The question is begged, therefore, as to whether the overall tradeoff is in the reader's favor.

For a textbook aimed at undergraduate students, seniors to be specific, the three new major coverages must be assessed in the light of their relevance to the aircraft structures theme per se. A chapter on the fundamentals of three-dimensional elasticity theory can be justified, of course, but only if the subsequent structural analysis developments are carefully related to elasticity theory and departures therefrom as they unfold. There is little opportunity to do so, however, as only two of the nine chapters which follow contain topical material and illustrative examples different from the first edition, a masterful exposition of the stress and deflection analysis of trusses, space frameworks, and the built-up sheet- stringer or semjmonocoque construction so common to flight vehicle airframes for five decades now.

Elasticity theory appears in the separate and brief chapter .on thermal stresses; however, illustrative examples are given only for a beam and a three-bar truss, respectively. With regard to thermal effects, they are fundamental to the constitutive equations of elasticity theory. Thus, they are conspicuous by their absence when the stress-strain relations of elasticity theory are first introduced.

The chapter on the finite element stiffness method is the significant new contribution to the book. Here a powerful and increasingly popular methodology is introduced to students, with the expertise of co-author Azar in this area obviously apparent. Unfortunately, all but one of the illustrative examples of the technique are restricted to this chapter. The three-bar truss example in the chapter on thermal stresses is the remaining instance. The analysis and design of typical members of aircraft structures which follow the introduction of the discretization approach use mainly conventional and, in one instance, finite difference methodology. These applications are basically similar to, if not the same as, their counterparts in the first edition.

If the aim of the revised text is simply to make students aware of some of the new developments and areas of interest which have surfaced in the period of the past three decades, then perhaps the objective has been attained. On the other hand, if the new thrust is supposed to be all-inclusive and to have the students learn to implement new theory and analysis techniques, then the goal has not been realized. For example, although laminated composite materials do not appear as an entry in the subject index, they are mentioned in several places in the text. In no illustrative example, however, is a laminate other than a unidirectional one considered; further, no connection is drawn between anisotropic composites and the general anisotropic medium for which constitutive relations are presented in the chapter on theory of elasticity. In a basic reference text which includes matrix methods, transformation of stress and strain, the definition of an orthotropic medium, mention of composites and their tailoring potential, and the concept of stress resultants, relatively little additional space would have to be accorded development of, say, composite plate extensional, coupling, and bending stiffnesses referred to overall laminate axes.

The referencing system used in the revised edition is frustrating to the reader. Although 104 entries appear in the reference list, less than half actually appear in the text; the references that can be identified are woefully out of order. Further, at least one reference has been located in the text which is absent from the reference list. In addition, few of the 30 or so references dated 1970 or later can actually be found in the body of a book which is purported to be up-to-date.

In summary, then, it would appear that there is insufficient inducement for those holding the first edition to invest in the second edition. For others, until the first edition copies are exhausted, the choice is arbitrary in view of the large portion of text that is common to both.

Professor J. Mayers

Stanford University

AutoCAD Workbook for Architects and Engineers by: Shannon R. Kyles

AutoCAD Workbook for Architects and Engineers


by: Shannon R. Kyles

AutoCAD Workbook for Architects and Engineers  library.nu #402117

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140518096X
9781405180962

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year: 2008
pages: 298
bookmarked: yes
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cover: yes
searchable: yes
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description: ( ? )

This practical step-by-step guide - designed for use at your computer - gives clear, compact instructions and self-test exercises to help you learn 2-D drawing using AutoCAD. The text is written for use on all AutoCAD releases from 2000 to 2008.
Computer-aided drawing is a skill that every student in architecture, engineering, the trades and construction must learn – and ideally at the computer, actually drawing things. AutoCAD is the most widely used package in the industry but existing teaching books tend to be too wordy and focus more on technical wizardry than on how to deliver actual finished drawings using industry drafting protocols.
AutoCAD Workbook gives you the skills you need for the full range of drawing types using a wide variety of commands and sequences. Each chapter - or teaching module – contains a brief introduction to the commands, explaining exactly how each one can be used, and plenty of exercises to demonstrate how to produce everything from working drawings to presentation drawings; and orthographic projection to pictorial views.
Examples include residential and commercial buildings for architects and designers; steel and concrete details for civil and structural engineering; mechanical parts and assemblies for mechanical engineering; and millwork and cabinet-making for woodworking applications.

Reinforced Concrete: Mechanics and Design (5th Edition)

Reinforced Concrete: Mechanics and Design (5th Edition)


by: James K. Wight, James G. MacGregor

Reinforced Concrete: Mechanics and Design (5th Edition)  library.nu #402276

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0132281414
9780132281416

metadata: ( ? )

year: 2009
pages: 1130
bookmarked: no
cover: yes
searchable: no


description: ( ? )

Reinforced concrete design encompasses both the art and science of engineering. This book presents the theory of reinforced concrete as a direct application of the laws of statics and mechanics of materials. In addition, it emphasizes that a successful design not only satisfies design rules, but also is capable of being built in a timely fashion and for a reasonable cost. A multi-tiered approach makes Reinforced Concrete: Mechanics and Design an outstanding textbook for a variety of university courses on reinforced concrete design. Topics are normally introduced at a fundamental level, and then move to higher levels where prior educational experience and the development of engineering judgment will be required.

Modern control systems part 1

morden control system part 1


by: Richard C.Dorf and Robert H.bishop

morden control system part 1  library.nu #401832

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status: normal
language: en [ english ]
submitted by: anonymous


no ISBNs present

metadata: ( ? )

scanned: yes


description: ( ? )

Written to be equally useful for all engineering disciplines, this book is organized around the concept of control systems theory as it has been developed in the frequency and time domains. It provides coverage of classical control employing root locus design, frequency and response design using Bode and Nyquist plots. It also covers modern control methods based on state variable models including pole placement design techniques with full-state feedback controllers and full-state observers. The book covers several important topics including robust control systems and system sensitivity, state variable models, controllability and observability, computer control systems, internal model control, robust PID controllers, and computer-aided design and analysis. For all types of engineers who are interested in a solid introduction to control systems.

Modern control systems part 2

modern control systems part 2


by: Richard C.Dorf and Robert H.bishop

modern control systems part 2  library.nu #402307

md5: 26d5919933367e3057c227cef6c9fd2b
size: 154.20 MB [ 161694285 bytes ]
type: .pdf
status: normal
language: en [ english ]
submitted by: anonymous


no ISBNs present

metadata: ( ? )

scanned: yes


description: ( ? )

Written to be equally useful for all engineering disciplines, this book is organized around the concept of control systems theory as it has been developed in the frequency and time domains. It provides coverage of classical control employing root locus design, frequency and response design using Bode and Nyquist plots. It also covers modern control methods based on state variable models including pole placement design techniques with full-state feedback controllers and full-state observers. The book covers several important topics including robust control systems and system sensitivity, state variable models, controllability and observability, computer control systems, internal model control, robust PID controllers, and computer-aided design and analysis. For all types of engineers who are interested in a solid introduction to control systems.

Cryogenic Technology and Applications

Cryogenic Technology and Applications


by: A.R. Jha

Cryogenic Technology and Applications  library.nu #387774

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submitted by: anonymous


0750678879
9780750678872
9780080457970

metadata: ( ? )

there is no metadata available to further describe this document


description: ( ? )




Cryogenic Technology and Applications
By A.R. Jha



  • Publisher: Butterworth-Heinemann
  • Number Of Pages: 296
  • Publication Date: 2005-11-18
  • ISBN-10 / ASIN: 0750678879
  • ISBN-13 / EAN: 9780750678872
  • Binding: Hardcover



Product Description:

Cryogenic Technology and Applications describes the need for smaller cryo-coolers as a result of the advances in the miniaturization of electrical and optical devices and the need for cooling and conducting efficiency. Cryogenic technology deals with materials at low temperatures and the physics of their behavior at these temps. The book demonstrates the ongoing new applications being discovered for cryo-cooled electrical and optical sensors and devices, with particular emphasis on high-end commercial applications in medical and scientific fields as well as in the aerospace and military industries.

This book summarizes the important aspects of cryogenic technology critical to the design and development of refrigerators, cryo-coolers, and micro-coolers needed by various commercial, industrial, space and military systems. Cryogenic cooling plays an important role in unmanned aerial vehicle systems, infrared search and track sensors, missile warning receivers, satellite tracking systems, and a host of other commercial and military systems.

* Provides an overview of the history of the development of cryogenic technology
* Includes the latest information on micro-coolers for military and space applications
* Offers detailed information on high-capacity cryogenic refrigerator systems used in applications such as food storage, high-power microwave and laser sensors, medical diagnostics, and infrared detectors

The Hydrogen Energy Transition: Cutting Carbon from Transportation

The Hydrogen Energy Transition: Cutting Carbon from Transportation


by: Daniel Sperling, James S. Cannon,

The Hydrogen Energy Transition: Cutting Carbon from Transportation  library.nu #385594

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status: normal
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submitted by: anonymous


0126568812
9780126568813
9780080495323

metadata: ( ? )

there is no metadata available to further describe this document


description: ( ? )



By Daniel Sperling, James S. Cannon,

  • Publisher: Academic Press
  • Number Of Pages: 266
  • Publication Date: 2004-06-14
  • Sales Rank: 768713
  • ISBN / ASIN: 0126568812
  • EAN: 9780126568813
  • Binding: Hardcover
  • Manufacturer: Academic Press
  • Studio: Academic Press
  • Average Rating: 3
  • Total Reviews: 1



Book Description:

The Hydrogen Energy Transition addresses the key issues and actions that need to be taken to achieve a changeover to hydrogen power as it relates to vehicles and transportation, and explores whether such a transition is likely, or even possible. Government agencies and leaders in industry recognize the need to utilize hydrogen as an energy source in order to provide cleaner, more efficient, and more reliable energy for the worlds economies. This book analyzes this need and presents the most up-to-date government, industry, and academic information analyzing the use of hydrogen energy as an alternative fuel.

With contributions from policy makers and researchers in the government, corporate, academic and public interest sectors, The Hydrogen Energy Transition brings together the viewpoints of professionals involved in all aspects of the hydrogen-concerned community. The text addresses key questions regarding the feasibility of transition to hydrogen fuel as a means of satisfying the worlds rapidly growing energy needs. The initiatives set forth in this text will mold the research, development and education efforts for hydrogen that will assist in the rapidly growing transportation needs for automobiles and other vehicles.

* Presentations by the world's leaders in government, industry and academia

* Real-world solutions for the world's current fuel crisis.

* Endorsed by the University of California Transportation Center and Transportation Research Board



Date: 2005-04-28 Rating: 3
Review:

Have We Passed Go in Hydrogen Energy for Transport?

The book is a collection of papers from the 2003 IX th Biennial Asilomer Conference, (plus two papers added after) on transportation and energy. It represents the very leading edge of debate and discussion on the petroleum-hydrogen transition and is, in my view, essential and useful reading, and a milestone reference work on the current `state of play'. By having contributions from a diverse range of sectors, the collection has a unique combination of those `for' and those `not-necessarily-against' hydrogen in energy systems and transportation. It is a useful and, by no means one sided, look at the key issues that are and need to be addressed. Some of the more provocative contributions are from those who seriously question whether we have been cajoled into a solution (hydrogen) which could be better dealt with by other means.

Daniel Sperling's introduction highlights key `drivers' of the progress to sustainable energy as increasing carbon dioxide emissions, the depletion of existing oil resources and persistent air pollution. The hindrances to progress are the commitment to the status quo by the automotive and energy industries and policy environments that unwittingly discourage significant change.

As such, the volume is not so much about the challenges to be overcome in making the transition to hydrogen energy, but more with the entire transformation of the distributed energy system of the entire globe and its adaptation to a new form over the next 70-90 years. Each of the diverse contributions looks at different aspects of the transition from coal (electricity) and oil (transportation) to both distributed hydrogen (electricity) and fuel cell power (transportation) systems.

David Scott examines the contrast between distributed electricity systems and a similar network for gaseous hydrogen. While his broad analysis of the long term transition to the hydrogen age is compelling, one kept asking where were the holdups to this gradual transition and how will we overcome them? Kenneth Kurani and others examines the future for hydrogen fuel cell vehicles and suggests that, rather than just being a question of changing the fuel type and reducing the running costs, the long term future for such vehicles will be determined by the fusing of several functions into a `mobility-information' platform. Only by doing so will the underlying basic needs be met as well as those of environmental protection and reduced use of fossil fuels.

Taiyo Kawai examines the challenge to build commercial fuel cell hybrid vehicles, and he concludes that the greatest challenge will not be the development of vehicle technology, which is readily adaptable, but rather the cost and development of hydrogen infrastructure. Joan Ogden follows the same line and asks the question: what is the best production and distribution pathway? The answer, she suggests is that it will depend upon both the geographic aspects of hydrogen demand, interdependencies with other energy systems, as well as the severe competition which fuel celled vehicles will face from traditional automobile technologies.

Richard Doctor and John Molburg plea for greater generation of hydrogen from coal in addition to the current use of reformation from natural gas. The high volume of CO2 generated in the process can be geosequestrated but public acceptance and costs are key uncertainties. David Bodde looks at the uncertainties of technology in the transition to hydrogen and suggests that policy can only `guide' in a very general sense; it can't `pick winners'. He sees the nurturing of entrepreneurial activity and private investment in the hydrogen related business as the key role for government.

Chip Schroeder (Proton Energy Systems Inc.) advocates the electrolysis of hydrogen from water as the only practical and sustainable solution for hydrogen fuel generation. But he also recognizes the practical limitations facing his company in developing proton exchange membrane electrolyzers; he sees niche markets with high value revenue generation as being the key to use of such technologies today. He sees no commercial sense in direct competition with established technologies who hold all the market advantages.

Steve Chalk and Lauren Inouye see US government R&D as essential to supporting the technical and economic feasibility of hydrogen power and fuel cells; but it also will need to develop codes and standards, and build human infrastructure necessary to ensure hydrogen safety. James Boyd, in discussing California's experience, asks whether we have learnt enough before embarking upon pathways which will not necessarily deliver what we seek; he sees an absolute necessity in not picking `winners and losers' in the process. A similar answer seems to apply to the European Union approach described by Barend van Engelenburg.

Jerry McNutt and David Rogers look at the lessons learnt from 15 years of alternative fuel programs and the major barriers which hydrogen will also face; lack of refueling infrastructure, high cost, conversion costs, market barriers, safety and reliability and vehicle driving range. They see no easy transition and infrastructure development as the major limiting factor. Bernard Robertson and Loren Beard see similar issues arising as result of DamlierChrysler's experiences with alternative fuel vehicles. Paul Leiby and Jonathan Rubin suggest that market barriers to hydrogen are substantial but that the world market price for oil will be a key `driver'; similarly by having the US sign the Kyoto protocol would have significant impacts and allow the alternative fuel and fuel celled vehicles to be rapidly competitive.

John DeCicco suggests the focus on hydrogen is premature at best, as the technology is not mature enough to justify mandated changes ahead of maturing the policy debate over air quality, global warming and energy security. Paul MacCready likewise suggests that the case for hydrogen fuel may be premature as the development of lithium battery technology has made it a viable source of propulsion energy for a range of mobile sources.

Daniel Sperling and James Cannon summarize the volume and point to the precarious situation which hydrogen based fuel systems find themselves; poorly supported and lacking the essential backing of strict air quality standards, the Kyoto protocols (in the US at least), or broad public support for global warming measures. Most of the short-term and intermediate gains which are desired on these issues he sees as being better provided by hybrid electric vehicles, cleaner combustion engines and cleaner fuels. He suggests that rather than mimicking existing energy distribution systems it may be that the only viable development of hydrogen fuels will be in the form of dispersed and small hydrogen refueling appliances at residences.

I found the volume to be a good summary of the current state of play that is neither too technical nor too simple in its treatment. It provides a useful insight into issues related to the hydrogen transition as well as the factors that are limiting to its wide adoption and development. Suitable for senior undergraduate as well as graduate standards, I recommend the volume as a topical collection of issues and debate which fellow `students' of the global energy scene will find both informative and thought provoking.

(Dr) Ian Lavering
Adjunct Professor
MBT Program UNSW

Electronics and Circuit Analysis Using MATLAB

Electronics and Circuit Analysis Using MATLAB


by: John Okyere Attia

Electronics and Circuit Analysis Using MATLAB  library.nu #331744

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language: en [ english ]
submitted by: anonymous


0849311764
9780849311765

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year: 1999
lcc: TK7835.A88 1999
ddc: 621.3810285


description: ( ? )

Useful to students, professional engineers, scientists, and technicians, Electronics and Circuit Analysis Using MATLAB·provides a simple, easy-to-understand, hands-on introduction to MATLAB·demonstrates the use of MATLAB for solving electronic problems·outlines various ways MATLAB solves circuit analysis problems·shows the flexibility of MATLAB for solving general engineering and scientific problemsThis book divides into three parts: introduction to MATLAB, applications of MATLAB in circuit analysis, and electronics applications with MATLAB. Topics covered include plotting functions, control statements, two-port networks, Fourier analysis, diodes, semiconductor physics, operational amplifiers, and transistor circuits.

Directional Drilling (Petroleum Engineering and Development Studies) (v. 2)









Directional Drilling (Petroleum Engineering and Development Studies) (v. 2)

by: T.A. Inglis








Directional Drilling (Petroleum Engineering and Development Studies) (v. 2)  library.nu #384393






















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size: 41.83 MB [ 43866476 bytes ]
type: .pdf
status: normal
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submitted by: anonymous


0860107167
9780860107163












metadata: ( ? )

there is no metadata available to further describe this document