Design buildings

The above discussion has simply concerned matching the wavelength of the transducer to the mode(s) of interest. However, the "excitability" of different modes by interdigital transducers is considerably more complex than this and has been discussed by many authors (see, for example, [8, 10-13]). In the case of a low impedance, relatively weakly piezoelectric material such as PVDF generating waves in a high impedance substrate such as steel, it is reasonable as a first approximation to consider the motions of the transducer and the substrate to be uncoupled. In this instance the transducer applies out-of-plane forces to the surface of the structure at the locations of the fingers. The transducers described here have been designed on this basis as discussed below, but work is now in progress to refine the design, building on the more sophisticated analyses in the literature.  [c.716]

BC 9 Detailed Design —> Building Layout and Structures  [c.23]

Building an irreducible structure. The first approach follows the onion logic, starting the design by choosing a reactor and then moving outward by adding a separation and recycle system, and so on. At each layer we must make decisions based on the information available at that stage. The ability to look ahead to the completed design might lead to different decisions. Unfortunately, this is not possible, and instead, decisions must be based on an incomplete picture.  [c.8]

In summary, the two general approaches to chemical process design of building an irreducible structure and creating and optimizing a reducible structure both have advantages and disadvantages. Whichever is used in practice, however, there is no substitute for understanding the problem.  [c.13]

A modular scanner system for NDE has been developed. It consists of a selection of individual electronics and motor module components, supported by scanner configuration and control software. The modules are used as standard building blocks for construction of job specific, dedicated scanners as well and general purpose scanners. The use of modular scanner components significantly reduce the work, time and cost not only for the design and manufacture but also for establishing documentation and ensure compliance with the relevant EU-directive requirements.  [c.805]

Fitting a ligand from a 3D structure database into the binding site of a target protein is called docking. The iterative building of new molecules in the binding site of a receptor is illustrated in the center and on the right hand side of Figure 10.4-5. These procedures to find new leads are called de novo design. The building approach, beginning with a single fragment and proceeding through the stepwise addition of further moieties, is shown in the center. Alternatively, several small molecules are placed in the binding site of the protein and subsequently linked together (linking). To end up with high-affinity ligands from structure-based drug design, a high degree of steric and electronic complementarity of the ligand to the target protein is required. Further on, an appropriate amount of the ligands hydro-phobic surface should be buried in the complex. A certain degree of conforma-  [c.608]

Figure 10.4-5. Different strategies to design a ligand in structure-based drug design docking (left), building (center), and linking (right), Figure 10.4-5. Different strategies to design a ligand in structure-based drug design docking (left), building (center), and linking (right),
The most stable conformation of 1 3 dioxan 5 ol is the chair form that has its hydroxyl group in an axial orientation Suggest a reasonable explanation for this fact Building a molecular model IS helpful  [c.696]

If a weigh vessel is located outdoors, the effect of wind forces on the vessel s stabiUty should be considered, particularly if it is a tall slender vessel in an exposed location. An empty vessel may be in danger of tipping wind forces transfer weight from one module to another and, when fiiU, may cause load-ceU damage. In many areas the effects of earthquakes must be considered in the design of the scale and its supporting stmcture. Building codes exist for the design of stmctures subjected to wind or seismic loading (15,16). In many instances a weigh module can be selected which can withstand these effects however, in some cases it may be necessary to add additional horizontal or vertical checking. Vessel stabiUty can be greatly improved if compression mounts are appHed in a horizontal plane close to the vessel s center of gravity this arrangement is convenient if the vessel passes through a floor, for example. AH vessels should have safety supports that can hold the vessel if failure of the primary support could lead to loss or injury. This safety backup could be provided by loosely fitting chains or check rods.  [c.337]

Flooding, often the most restrictive of the limitations, occurs when the clear Hquid height in the downcomer, exceeds a certain fraction of the tray spacing. During operation, the Hquid level in the downcomer builds up as a result of the head necessary to overcome the various resistances to Hquid flow, including the friction in the downcomer itself and the hydrauHc gradient across the plate. A significant portion in the Hquid backup is caused by the need for the Hquid to overcome the difference in pressure between the inside and the outside of the downcomer, which in turn is caused by the pressure drop of the vapors through the next higher plate. If the diameter of the column is made too small for a given flow, the vapor pressure drop and thus the Hquid backup in the downcomers will increase to the point where some Hquid spills onto the next higher tray, and flooding sets in. In principle, the condition may be corrected by increasing the diameter or the tray spacing. A conservative design requires a clear Hquid head in the downcomer of no more  [c.43]

Energy Conservation. The design of systems that conserve energy requires knowledge of the building, its operating schedule, and the systems to be installed (see Energy management). The foUowing approaches lead to reduced energy consumption  [c.362]

Understanding of fires dates to the nineteenth century. The advent of modem fire fighting techniques and equipment has meant less destmction of cities or whole buildings. Additionady, fire-resistant building design usuady contains fires to parts of stmctures. However, a high fuel load ia either a residence or a commercial building can overwhelm even the best of building constmction.  [c.451]

Fundings, 78 (Oct. 1978) Building Design eA Construction, 134 (May 1983).  [c.392]

The refractory used to constmct the hearth can be in the form of bricks, preformed shapes, or monolithic. Often a furnace design utilizes all three. Openings or passageways through the walls are fashioned in the same manner as windows in a brick building.  [c.131]

Conceptual Design of MHD Repowered Plant. The first step toward MHD plant commercialization is a pilot-scale demonstration plant. Repowering of existing plants, actively under study both in the United States and elsewhere (65), allows use of existing systems at considerable cost savings compared to building a new plant from the ground up. It also ensures that the pilot scale demonstration occurs in a reaHstic utiHty environment and  [c.435]

Besides planning a facility around its products and occupancy, it is also important to design a facility with future sustaining maintenance in mind, eg, adequate space must be allowed around machinery, and heavy and large equipment should be placed next to doors and hallways for future moves. Heavy and large equipment on roofs should be placed as close to the edge of the building as possible. A freight elevator should be provided to handle moving of equipment and material to all levels including the roof.  [c.441]

In a mature facility the design team for a new building or an addition to an old building should seek input from the maintenance department. Maintenance workers know what equipment and material is difficult to maintain, and the standard in the existing facility employed in order to prevent stocking of many different replacement parts.  [c.441]

The American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) and the American National Standards Institute (ANSI) have provided standards for architects and engineers who specify HVAC systems. Sufficient and clean make up air must be provided at all times for a healthy building occupancy. It is the maintenance department that must make sure that the HVAC systems are clean, maintained properly, and operate within design specifications. Every maintenance worker must be empowered to care for the air handling and exhaust system of the facihty as part of his or her ownership responsibihty.  [c.444]

Computerization. The computerization of all aspects of industry and commerce, from management to engineering and manufacturing, and from purchasing to sales, has made it vital to standardize the ways materials information is incorporated into machine-readable systems (see Computer-aided design and manufacturing Computer-aided engineering). The designation of materials, the recording of properties, as well as auxihary information, can all be computerized. More than a dozen standards in this area have been developed by ASTM s Committee E49 who have also prepared a guide to the building of materials databases (qv) (39). A particularly important issue is standardization to facihtate the exchange of digital information. Internationally, work toward this goal is carried out under the aegis of ISO-STEP (standard for the exchange of product data). STEP, known formally as ISO 10303, covets all aspects of information needed to describe manufactured products including shape, product configuration, and process description. Materials ate coveted in Part 45 which treats material stmcture, properties, and measurement conditions in such a way that the information is fully integratable with other parts of the STEP standard. Implementation for materials awaits the development of particular appHcation protocols (APs), eg, composite part design or polymer testing. The STEP model has been mote fully described (39,40). Status is available from the ISO-STEP secretariat at NIST.  [c.22]

Account must be taken in design and operation of the requirements for the production and consumption of xenon-135 [14995-12-17, Xe, the daughter of iodine-135 [14834-68-5] Xenon-135 has an enormous thermal neutron cross section, around 2.7 x 10 cm (2.7 x 10 bams). Its reactivity effect is constant when a reactor is operating steadily, but if the reactor shuts down and the neutron flux is reduced, xenon-135 builds up and may prevent immediate restart of the reactor.  [c.212]

An example of the large reactor concept as appHed to the PWR is the System 80+ of ABB Combustion Engineering, designed in conjunction with Duke Engineering Services. System 80+ is an extension of System 80 that embodies several features, such as safer design, simpler design, greater reHabiHty, and enhanced operabiHty. It has a large spherical steel containment building, gravity feed for the emergency water, hydrogen control, and decay-heat  [c.224]

Whereas these design measures provide the primary assurance of protection from the harmful effects of radiation, additional protection is provided in the unlikely event that the integrity of the systems or components break down. The entire portion of the nuclear plant containing radioactive material is enclosed in a strong containment building. If a release of radioactivity from the plant were to occur, the radioactive material would be captured within the containment building. As a further precaution, these processes are subject to continual cross-checks by people separate from those engaged in the design, fabrication, constmction, and operational processes. Cross-checks in the form of design reviews, inspections, operations, and safety audits are carried out. The U.S. nuclear industry has set up the Institute of Nuclear Power Operations (INPO) to estabUsh operations and training standards and to audit nuclear plant operations for compliance with those standards. In addition, a totally independent body responsible to the pubHc, the U.S. Nuclear Regulatory Commission (NRC), estabUshes overriding safety regulations and monitors compliance.  [c.234]

IAEA also defines the fundamental responsibiUties for nuclear power plant safety as ultimately resting with the operating organisation (12). Designers, suppHers, constmctors, and regulators are also responsible for their separate activities. ResponsibiUty is reinforced by the estabUshment of a safety culture, ie, "the personal dedication and accountabiUty of all individuals engaged in any activity which has a bearing on the safety of nuclear power plants" (13). Safety design of nuclear power plants is founded on the defense-in-depth concept, which provides multiple levels of protection to both the pubhc and the workers, in the form of physical barriers and levels of implementation of the associated defenses. Each of the multiple physical barriers prevents the release of radioactive materials, but all envelop a given number of the others so that if an inner barrier fails, the next outer barrier holds back the radioactive material (8,12,14). Eigure 1 shows both the physical barriers and the multiple levels of protection in conceptual form. The first barrier is the nuclear fuel rod which heats up as fission occurs. The fuel rod is made up of corrosion-resistant ceramic and uranium oxide pellets, placed in tubes called cladding (see NuCLEAR REACTORS, NUCLEAR FUEL RESERVES), comprising the second barrier which surrounds the nuclear fuel. The cladding is made of a metal alloy, usually Zircaloy, which is highly corrosion-resistant. The third barrier is a steel pressure boundary, consisting of the reactor pressure vessel. AH the core is placed within this vessel, as is the main coolant piping which contains the cooling water that takes the heat from the fuel and transfers it to provide the electricity. The fourth barrier is the containment building, a massive reinforced concrete or steel stmcture within which is placed the nuclear portion of the power plant s generation system, called the nuclear steam supply system.  [c.235]

Another design feature is the provision for on-line coolant leakage monitors that would signal incipient pressure boundary failure. Radiation monitors are installed in the containment building to detect airborne radioactivity, which would signal incipient loss of integrity of some part of the pressure boundary. Extensive inspection requirements are also stipulated. Sensitive ultrasonic devices are used to check the condition of the piping (see Piping systems). Samples of the reactor pressure vessel material are removed from the reactor zone periodically to be tested for ductihty loss. Eddy current detectors are used to inspect the steam (qv) generator tubes for the occurrence of cracking (see Nondestructive evaluation).  [c.236]

Fourth Barrier. The design feature of the fourth barrier is the containment building. It is designed to withstand the high temperatures, pressures, and radiation resulting from a severe accident entailing fuel meltdown. Supplementary features are utilized to reduce the consequences of such severe accident conditions spray systems are installed to reduce the containment temperature catalytic devices are provided to absorb airborne fission products igniters are installed to bum off hydrogen gas emitted during an accident before the deflagration temperature is reached interlocks and alarms are activated to assure that containment hatches are appropriately closed and periodic testing of the leak-tightness of the containment is carried out.  [c.236]

Attention to various physiochemical parameters of the dmg moiety, such as particle size, crystalline form, and solubihty, is vital to the design of a dosage form, as are its purity and accurate measurement. Nontherapeutic or excipient ingredients are selected to ensure stabihty (buffers, chelating agents (qv), antioxidants (qv), antimicrobial preservatives), and accuracy and precision of dosage (diluents, vehicles). Similarly, various types of excipients are used for specific types of dosage forms in order to permit theh manufacture and desired therapeutic performances, eg, disintegrating agents for compress tablet formulations. Other excipients function as processing aids for example, ghdants that ensure effective flow of granulation during tablet compression. Lubricating agents are sohds used in tablet compression to lubricate the die-wahs and punch faces to prevent sticking, capping, and/or excessive die-wah wear. Polymers find wide excipient use in dosage form design as viscosity-building agents in suspensions and emulsions and in the control of dmg release in products prepared to achieve longer (8—12 h) than usual therapeutic periods. Various excipients are used to provide dmg palatabihty for patients, eg, colorants (see Colorants for food, drugs, cosl tics, and l dical devices) and flavoring agents (see Elavors and spices) (15).  [c.224]

Electric Furnace. Two basic types of phosphoms furnaces based on electrode configuration are in use. First, the in-line type having three electrodes lined up in a row allows for a simpler layout and a rectangular furnace design at the expense of electrical energy efficiency. Single-phase transformers incorporating Y or delta electrical connections having power ratings of 15—40 MW are typical of operating in-line furnaces. Second, the delta type of furnace uses a three-electrode, symmetrical triangular configuration with a three-phase Y or delta electrical connection operating in the 45—65 MW range at potentials of 200—650 V. World class phosphoms furnaces are of this type. The delta furnace is circular, polygonal, or of a rounded triangular cross-section type. A typical delta furnace along with accompanying off-gas handling system is shown in Figure 3. The furnaces are basically mn continuously, except during repairs, process upsets, power curtailments, or electrode building. Typical operating characteristics for a large (60-MW), phosphoms furnace are shown in Table 2.  [c.350]

The electrodes are cylindrical and hang vertically in the furnace from suspension cables or hydraulic, water-cooled electrode clamps, which allow up-and-down movement of the electrode via an automated amperage control system. Prebaked carbon—graphite electrodes are used exclusively in domestic furnaces, with some foreign facilities utilising Smderberg electrodes. Electrodes of 110—140 cm diameter and a nominal 2.5-m length are generally used. A tapered male—female thread design is used to build electrodes on top of one another as they are consumed in the furnace at about 15—30 kg per 1000 kg phosphoms. Substantial mechanical and thermal stresses are imposed on the electrodes during operation and can result in electrode breakage which can severely affect furnace operation and on-stream time. Proper attention to assuring electrode quality, joint integrity, and building procedures is essential. Electrodes carry up to 65 kA, which necessitates careful attention to electrical design in order to optimize the furnace power factor, which is about 0.96—0.98. Some producers have developed hoUow electrode technology to convey carbon-coke fines direcdy into the reaction zone at the tip of the electrode, which results in decreased electrode consumption.  [c.351]

Process Plant Ha ard and Control Building Design, Chemical Industries Association (U.K.), 1979.  [c.104]

Moisture. Absorbed and retained moisture, especially as ice, has a significant effect on the stmctural and thermal properties of insulation materials. Most closed-ceU plastic foams have low permeance properties most notably where natural or bonded low permeance surface skins exist (29,30). Design, building, and constmction practices requite adequate vapor retarders, skins, coatings, sealants, etc, in order to prevent the presence of moisture. However, moisture vapor cannot be completely excluded, thus the possibiUty of moisture absorption and retention is always present. The freezing of moisture and mpturing of cells result in permanent reduction of thermal and stmctural performance.  [c.335]

The locations where this is liable to occur are predictable to some extent from the databases such as those maintained by classification and,in the case of tankers,from the data published by other sources, notably the Tanker Structure Co-operative Forum. With regard to new building, all tankers tmd bulk carriers longer than 190m and classed by LR have been subject to ShipRight Structural Design Assessment and Fatigue Design Assessment. With the ShipRight programme an assessment of the fatigue life of structural details can be made.  [c.1046]

Moore J H, Davis C C and Copian M A 1989 Building Scientific Apparatus 2nd edn (Redwood City, CA Addison-Wesiey) ch 5 The fundamentais of eiectron opticai design.  [c.1328]

The redox properties of pristine fullerenes and monofunctionalized fullerene derivatives in tlieir ground and excited states have drawn much attention for tire design of devices such as molecular switches, receptors, photoconductors and photoactive dyads 1175, 176 and 1771. These applications are generally based on tire implication of fullerenes as a multifunctional electron storage moiety. The excellent electron accepting properties of fullerenes, togetlier witli tlieir low reorganization energy, makes [60]fullerene and its derivatives good candidates for building blocks of systems employable for solar energy conversion, batteries and photovoltaics. The concept of linking fullerenes to a number of interesting electro- or photoactive species offers new opportunities in tire preparation of materials witli building blocks having highly symmetrical and coordinating geometries.  [c.2422]

There were some clear signs that the situation was changing. In 1975 the Journal of Otemical Documentation changed its name to Journal of Chemical Information and Computer Sciences. In 1973 a seminal NATO Advanced Study Institute Summer School was held in Noordvdjkerhout, The Netherlands, that for the first time brought together a broad range of scientists who came from different areas of chemistry but who were all developing computer methods to manage and make sense of chemical information. The title of the Summer School was " Computer Representation and Manipulation of Chemical Information". The groups attending this conference worked on building chemical structure databases and on developing software for molecular modeling, for organic synthesis design, for analyzing spectral information, and for chemometrics. Suddenly it was realized that a new field had emerged that had implications in many areas of chemistry.  [c.4]

HyperChem should not he viewed as a black box that computes on ly wb at its design ers th ougb L correct, tthasan open architecture that makes it possible to customize it many ways. As far as is possible, the parameters of molecular mechanics and semi-empir-ieal calculations are in the user s baruis. As the tech n ic ues of software engineering advance and onr expertise in building new  [c.157]

Our institute building was designed in the fall and winter of 1977, working with the noted LA architect William Pereira and his firm. Jerry Segal and Tony Lazzaro, USC vice president in charge of facilities, were most helpful in the process. The institute was given a central location 111 the middle of the campus adjacent to other science and engineering buildings. It replaced some World War Il-vintage barracks still used for smaller classes and storage. The design provided a functional building, well suited for chemical research but at the same time also an attractive home for faculty, students, and staff. We were working with a small budget ( 1.7 million), which translated to the cost of 100/sq. ft. in determining the size of the building. Obviously, much needed to be  [c.118]

The accuracy of molecular mechanics and that of molecular dynamics simulations share an inexorable dependence on the rigor of the force field used to elaborate the properties of interest. This aspect of molecular modeling can easily fill a volume by itself. The topic of force field development, or force field parameterization, although primarily a mathematical fitting process, represents a rigorous and highly subjective aspect of the discipline (68). A perspective behind this high degree of rigor has been summarized (69). Briefly put, the different schools of thought regarding the development of force fields arose principally from the initial objectives of the developers. For example, in the late 1960s through the 1970s, the AUinger school targeted the computation of the stmcture and energetics of small organic and medicinal compounds (68,70,71). These efforts involved an incremental development of the force field, building up from hydrocarbons and adding new functional groups after certain performance criteria were met, eg, reproduction of experimental stmctures, conformational energies, rotational barriers, and heats of formation. Unlike the consistent force field approach of Lifson and co-workers (59,62—63,65), the early AUinger force fields treated a dozen or more functional groups simultaneously, and were not derived by an analytical least squares fit to aU the data (61). However, because the focus of Lifson was the analysis and prediction of the properties of hydrocarbons or peptides, it was not surprising that a consistent force field was possible. The number of variables to be optimized concurrentiy to permit calculation of aU the stmcture elements, conformational energies, and vibrational spectra concurrentiy was, and stiU is, a massive quantity. However, the calculation for a limited number of functional groups could be accompHshed, albeit slowly. If the goal is to reproduce and predict vibrational spectra, the full second derivative force  [c.164]

C. J. Hilado and R. W. Murphy, Design of Buildings forPire Safety, ASTM Spec. Tech. Publ. STP 685,16-105 ASTM, Philadelphia, Pa., 1979.  [c.425]

MAGGS-II. The Molecular Access System is a chemical information management system from Molecular Design Limited (MDL), San Leandro, California. It offers menu-driven graphical input for building, maintaining, and accessing chemical stmctures and any associated data, eg, chemical and physical properties, biological activity, toxicity data, pricing, safety, and suppHer information. Substmcture searches are done by drawing the compound with a mouse or light pen and activating the search process. The software interprets the drawn atoms, bonds, and stereochemistry of a chemical stmcture retrieves appropriate compounds and graphically displays them with their corresponding data. MACCS-II allows for customi2ation of the environment to suit various appHcations. Because it is designed for both mini- and main-frame computers, this system is suited for developing proprietary personal or corporate databases in which unique or new compounds can be registered together with the data of interest (112). Several companies such as Sando2 and Zeneca have taken advantage of this feature.  [c.130]

Specialty Skills Contracts. These contracts might handle work such as janitorial, window washing, painting, gardening, security guards, parking lot sweeping, weed and pest control, iastmmentation maintenance and caUbration, air conditioning filter service, water treatment, fire prevention equipment maintenance, lighting replacements and group relamping, pubHc address and music service, reproduction equipment maintenance, vehicle fleet maintenance, waste disposal, laundry service, cafeteria operation, cafeteria equipment, and vending machines maintenance. This Hst includes only the more common contracted services. These contracts should be negotiated while a new building is being constmcted, and the services must be operational when the building is ready for occupancy. A contractor of such services, if consulted duriag the building design and constmction phase, can often make valuable suggestions that will save on maintenance and operating costs.  [c.443]

In the past, energy was so plentiful and inexpensive that faciUties were not designed with energy conservation in mind. In the 1990s, however, architects and engineers must design any new building with the following points in mind careful orientation of the building, adequate insulation and choice of exterior glass, lighting level and use of low energy-consuming lighting, low energy-using HVAC systems that make use of heat recovery, and reuse of water.  [c.444]

The accident in 1979 at Three Mile Island Unit 2 (TMI-2), although highly pubhci2ed and very cosdy to clean up, resulted in minimum ha2ard to the pubhc. The design included a thick steel reactor vessel and a tight containment building. The incident resulted from mechanical failure compounded by misinterpretation of events by the operating crew. The TMI-2 accident, which prompted a number of improvements in equipment and procedures, also led the nuclear industry to create the Institute of Nuclear Power Operations (INPO), a self-regulatory organi2ation. The INPO maintains extensive safety-related databases, conducts power plant visits, and oversees operator training programs.  [c.181]

Chemobyl-4 was completely destroyed in a violent explosion in 1986. The roof of the reactor building blew off and the graphite caught on fire and released radioactive fuel into the atmosphere. A number of workers were killed and the pubHc was exposed to radiation. The accident was caused by a combination of reactor design features and operational errors performance of an experiment that bypassed the safety equipment, without evaluation of ha2ardous consequences removal of all safety rods during the course of the experiment in order to raise the reactor power inadequate speed of control by the neutron-absorbing rods and an inherently unsafe design, having a positive temperature coefficient of reactivity. It is generally beheved that the consequences of the Chernobyl accident would have been far less serious if there had been a containment of the type used in Western reactors, rather than simple confinement by a conventional building (44).  [c.214]

Scale Models. Rephcas of a plant are often prepared as part of the design and can be in several forms equipment only, equipment and major piping, or complete equipment and piping. Model building is both time-consuming and expensive. Models of whole fachities can easily cost millions of doUars but the money is considered weU-spent by many operating companies. The model can be used as a design tool, a constmction aid, and an operation and training aid. When the fachity has complex piping, 3-D visuali2ation can be depicted on a model that can make for a much more desirable operational layout. Scale models are quickly being replaced by 3-D CAD models.  [c.83]

See pages that mention the term Design buildings : [c.423]    [c.65]    [c.1096]    [c.39]    [c.62]   
Corrosion, Volume 2 (2000) -- [ c.9 , c.41 ]