UK PubMed Central (United Kingdom)

This paper summarizes the findings for the African Region of the WPA Task Force on Steps, Obstacles and Mistakes to Avoid in the Implementation of Community Mental Health Care. We present an overview...Full Text Available

International Nuclear Information System (INIS)

The term 'Post-CHF' was generally used in the two-phase flow regime in tube flow occurring downstream of the CHF. It has various other names such as dispersed flow, liquid-deficient flow, mist flow and film boiling because the two-phase regime is characterized by a continuous vapor phase with discrete liquid drops and a non-wetted heated surface. The regime has been adopted in a lot of applications including nuclear power plants, fossil power plants, steam generators, refrigeration systems and spray cooling, In particular, this regime has a considerable importance in the areas of light water reactor(LWR) accident analysis (off-normal operating conditions) and design in heat exchangers operating in the once-through mode where subcooled liquid enters the exchanger and superheated vapor exits. Recently, innovative PWRs adopt very high power density increases and so require increased safety margins. For instance, advanced PWRs would be going to use a new-type of spacer ...

Energy Technology Data Exchange (ETDEWEB)

The real thermodynamic inefficiencies in a thermal system are related to exergy destruction and exergy loss. An exergy analysis identifies the system components with the highest exergy destruction and the processes that cause them. However, only a part of the exergy destruction in a component can be avoided. A minimum exergy destruction rate for each system component is imposed by physical, technological, and economic constraints. The difference between the total and the unavoidable exergy destruction rate represents the avoidable exergy destruction rate, which provides a realistic measure of the potential for improving the thermodynamic efficiency of a component. The calculation of avoidable cost rates associated with both exergy destruction and capital investment is described in the paper and is applied to the exergoeconomic evaluation of an externally fired ...

Energy Technology Data Exchange (ETDEWEB)

Establishing germplasm of woody plants in microculture as shoot cultures has proved to be an effective method of overcoming many of the obstacles in working with these crops. Shoot cultures eliminate the changes associated with seasonal growth cycles and phase change and put large plants into a more manageable form. Well-established shoot cultures are central to successful clonal propagation systems for forest trees as well as to genetic improvement based on the use of cellular techniques such as protoplast manipulation. The physiological basis as to why tissues from shoot cultures are so readily manipulated is not well understood.

Energy Technology Data Exchange (ETDEWEB)

Steel structures immersed in seawater are protected from corrosion using cathodic protection systems (sacrificial anodes or impressed current), by paint coatings or by duplex systems in which cathodic protection hinders corrosion at coating's failure sites. The main problem related to those duplex systems is how to avoid cathodic delamination due to the alkalinity generated at cathodic sites. The present paper analyses the effectiveness of red mud suspensions as pre-treatment to avoid cathodic delamination. The study was conducted using mainly electrochemical impedance spectroscopy (EIS). The evolution of the electrode potential with immersion time was also recorded because it concerns the practical aspect of current density necessary to reach the protection potential. The study shows that red mud pre-treatments are effective in avoiding ...

Energy Technology Data Exchange (ETDEWEB)

As network bandwidth continues to grow and longer paths are used to exchange large scientific data between storage systems and GRID computation, it has become increasingly obvious that there is a need to deploy a packet drop avoidance mechanism into network transmission protocols. Current end-to-end congestion avoidance mechanisms used in Transmission Control Protocol (TCP) have worked well on low bandwidth delay product networks, but with newer high-bandwidth delay networks they have shown to be inefficient and prone to unstable. This is largely due to increased network bandwidth coupled with changes in internet traffic patterns. These changes come from a variety of new network applications that are being developed to take advantage of the increased network bandwidth. This paper will examine the end-to-end congestion avoidance mechanism and perform a step-by-step analysis of its theory. In addition we ...

Energy Technology Data Exchange (ETDEWEB)

Experimental investigations were performed to assess the effects of different shaped obstructions on flame propagation in a rectangular confinement, 235 mm in height, with a 1000 x 950mm cross section and a large top-venting area of 1000 x 320mm. Four different single obstacles were used: rectangular, cylindrical, triangular, and square cross-sections with blockage ratios of 5 and 10%. Temporally resolved flame front images were recorded by a high-speed video camera to investigate the interaction between a propagating flame and the obstacle. The local flame displacement speeds and their probability density functions (pdfs) were obtained for the different obstacles. Before the freely propagating flame impinges on the obstacle, the flame propagation speed remains close to the laminar burning velocity, regardless of the obstacles used. As the propagating flame impinges on the ...

Energy Technology Data Exchange (ETDEWEB)

Automated, variable volume unloaders provide the ability to smoothly load/unload reciprocating compressors to maintain ideal operations in ever-changing environments. Potential advantages provided by this load control system include: maximizing unit capacity, optimizing power economy, maintaining low exhaust emissions, and maintaining process suction and discharge pressures. Obstacles foreseen include: reliability, stability, serviceability and automation integration. Results desired include: increased productivity for the compressor and its operators, increased up time, and more stable process control. This presentation covers: system design features with descriptions of how different types of the devices were developed, initial test data, and how they can be effectively operated; three actual-case studies detailing the reasons why automated, hydraulically controlled, variable volume, head-end unloaders were chosen over ...

Energy Technology Data Exchange (ETDEWEB)

At the 1996 Conference in North Carolina, The Green Institute began to share its story. Their presentation this year will cover where they are in the design process and their plans for using solar and wind technologies in the development of an Eco-Industrial Park and Business Incubator. Located in a Federal Enterprise Community in Minneapolis, this project borrows sustainable and green building principles using the Rocky Mountain Institute and Solar Living Center as models. Using a change in the paradigm regarding how industry does business, The Green Institute is joining with developments across the country that are putting together Eco-Industrial Parks which use closed loop production systems to reduce waste and emissions generated from manufacturing processes. Using renewable energy, both solar and wind, presents challenges both in the integration of systems on this small site and the educational opportunities with a large potential audience ...

International Nuclear Information System (INIS)

Control of pressure transients in a hydraulic system may be important and necessary to avoid failures and to improve the efficiency of operation. Flow restricting devices can result in a decrease in the peak pressure, but may change the response time. The response time has an important effect on both operator and operator perceived smoothness. The response time should correspond to how fast a system responds to a given disturbance at the system boundary. Occasionally the appropriate response time is not easily determined. This study is on the response time characteristics in the hydraulic system studied for the control of response time.

International Nuclear Information System (INIS)

In order to evacuate the residual power in a nuclear reactor, a thermal valve system is presented for the modification of the heat exchange conditions at the pool exchanger level, which avoids the use of mechanical valves on the pipes. The system involves a vessel containing the exchanger, with openings at the upper end of the vessel and means for feeding the fluid at the lower end, and means for controlling the opening width.

Energy Technology Data Exchange (ETDEWEB)

Two of the US Department of Energy's (DOE) nuclear waste management-related goals are to ensure that waste management is not an obstacle to the further development of light-water reactors and the closure of the nuclear fuel cycle and to fulfill its institutional responsibility for providing safe storage and disposal of existing and future nuclear wastes. As part of its approach to achieving these goals, the Office of Remedial Action and Waste Technology of DOE established what is now called the Nuclear Waste Treatment Program (NWTP) at the Pacific Northwest Laboratory during the second half of FY 1982. To support DOE's attainment of its goals, the NWTP is to provide technology necessary for the design and operation of nuclear waste treatment facilities by commercial enterprises as part of a licensed waste management system and problem-specific treatment approaches, waste form and treatment process adaptations, equipment ...

Energy Technology Data Exchange (ETDEWEB)

The magnitude of Russian foreign debt, both official bilateral and commercial, compounded by collapse of the Russian economic system, is an obstacle in preventing the Russian Federation from effectively increasing the domestic priority of drawing down its nuclear weapons complex and providing a healthy, competitive environment to its nuclear cities. Debt-for-nature swaps, introduced in the early 1980s, provide debtor nations with a means of converting a portion of foreign debt into local currency, often at steep discounts, to use for purposes such as environmental protection that serve both a domestic and international need. This paper presents the debt-for-nature concept as a model for providing an infusion of funds to further U.S. and international nonproliferation objectives to help stabilize Russian closed city economic conditions through direct work on proliferation problems and remediation of the environment. A specific proposal is ...

Science.gov (United States)

A computer was built for use with the NRU reactor to solve the problem of Xe/sup 135/ concentrations. The effect of any changes in reactor on Xe/sup 135/ concentration can be predicted and steps taken to avoid poisoning out. An electromechanical system was used for the computer to avoid the inherent disadvantages that electronic analog computers present for problems of very long solution times. The electromechanical analog computer has a high order of reliability and contains no vaccum tubes, commutators, slip rings, relays, or aluminum electrolytic capacitors. It is insensitive to transient disturbarce. In the event of failure of components or interruption of line voltage, it will retain existing information. The computer was designed for ~ 1% accuracy in Xe/ sup 135/ concentration readings. (W.D.M.)

CERN Document Server

Fragile volatile aggregates with extremely low albedo, gravitationally drawn into the solar system are likely from the dark matter dominating the universal mass. Characteristics of this meteoric population permitted avoiding detection through a half-century's search. Measurements from space probes and in the upper atmosphere prove their existence and confirm their elusive properties.

Energy Technology Data Exchange (ETDEWEB)

Often measures of protection and restoration of reinforced concrete structures are not taken until damage occurs which affects power plant operation. These failures can be avoided by predictive civil engineering maintenance and repair. The consequent application and implementation of a life-time management system for power plant buildings is being suggested. (orig.)

International Nuclear Information System (INIS)

As the nuclear world is changing, the non-proliferation and safeguard systems have to change along the global development. Nuclear security as well as safety must be involved in all phases. Thus, modernization of thinking is a must. State system of accounting for and control of nuclear material (SSAC) is a basis, but now it is time to move ahead. Safeguards is not any more only to verify the declared nuclear materials but it is to inform the international safeguards society transparently but confidentially about the nuclear fuel cycle related activities and trade, and to confirm that there are no undeclared activities related to the nuclear fuel cycle in the states. Only strong SSAC with enhanced capabilities, activities and rights can meet the demand. The proliferation of nuclear weapons is a threat that also urges cooperation at all levels. International, regional and state systems must work closely together, and there is ...

UK PubMed Central (United Kingdom)

Low membrane permeability is one of the major obstacles to the successful cryopreservation of zebrafish embryos. The aim of the present study was to explore if this could be overcome by yolk...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundMultidrug resistance (MDR) is a major obstacle in cancer treatment and is often the result of overexpression of the drug efflux protein, P-glycoprotein (P-gp), as a consequence...Full Text Available

UK PubMed Central (United Kingdom)

The extensive diversity of Plasmodium falciparum antigens is a major obstacle to a broadly effective malaria vaccine but population genetics has rarely been used to guide vaccine design....Full Text Available

UK PubMed Central (United Kingdom)

One of the main obstacles encountered when trying to culture human seminoma (SE) cells in vitro is massive degeneration of the tumour cells. We investigated whether dissociation of tumour tissue, to...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The great advantage of the helical ionization cooling channel (HCC) is its compact structure that enables the fast cooling of muon beam 6-dimensional phase space. This compact aspect requires a high average RF gradient, with few places that do not have cavities. Also, the muon beam is diffuse and requires an RF system with large transverse and longitudinal acceptance. A traveling wave system can address these requirements. First, the number of RF power coupling ports can be significantly reduced compared with our previous pillbox concept. Secondly, by adding a nose on the cell iris, the presence of thin metal foils traversed by the muons can possibly be avoided. We show simulations of the cooling performance of a traveling wave RF system in a HCC, including cavity geometries with inter-cell RF power couplers needed for power propagation.

Energy Technology Data Exchange (ETDEWEB)

A respected veteran among state utility regulators raises a sober warning that it may not be possible for the telecommunications industry to survive half regulated and half unregulated, which is its posture for the present. He foresees a danger that the unregulated sector may be successful in capturing all the profitable portions of the market, leaving only the unprofitable areas to the regulated sector, which will then experience serious dislocations and even system breakdowns. Avoidance of such an outcome to the deregulatory steps presently being taken will require an uncommon degree of prudence and wisdom in those state officials who remain charged with regulatory responsibility for local exchange telephone facilities and service.

Energy Technology Data Exchange (ETDEWEB)

With the compensator-series equipment put into operation in 1992 - giving a performance of 330 Mvar - it was made possible for high-performance electronics to use a continuously variable, fully loaded power transmission line and to regulate the energy flow and minimise overcurrent losses. As well as these technical qualities, this system could offer environmental advantages for European implementation. This would avoid the need to plan and construct new high voltage transmission lines in order to meet increased demand. (orig.)

British Library Electronic Table of Contents (United Kingdom)

There is increasing pressure to operate laboratory facilities in environmentally and financially sustainable ways. A key factor in achieving this goal is careful consideration of how energy is used by the buildings' ventilation system, both for conditioning air supplied to the laboratories and the energy used moving air through the building. Traditionally, laboratory energy use is treated as an engineering concern within the scope of the building's overall design and operation. However, this approach limits the involvement of key stakeholders in many important decisions and can lead to unexpected safety concerns for the laboratory's users. We believe that a broad view of the parties affected by a laboratory building's operations is necessary to avoid having the various stakeholders working...

CERN Document Server

A major goal in optomechanics is to observe and control quantum behavior in a system consisting of a mechanical resonator coupled to an optical cavity. Work towards this goal has focused on increasing the strength of the coupling between the mechanical and optical degrees of freedom; however, the form of this coupling is crucial in determining which phenomena can be observed in such a system. Here we demonstrate that avoided crossings in the spectrum of an optical cavity containing a flexible dielectric membrane allow us to realize several different forms of the optomechanical coupling. These include cavity detunings that are (to lowest order) linear, quadratic, or quartic in the membrane's displacement, and a cavity finesse that is linear in (or independent of) the membrane's displacement. All these couplings are realized in a single device with extremely low optical loss and can be tuned over a wide range in situ; in ...

CERN Document Server

Many secure communication libraries used by distributed systems, such as SSL, TLS, and Kerberos, fail to make a clear distinction between the authentication, session, and communication layers. In this paper we introduce CEDAR, the secure communication library used by the Condor High Throughput Computing software, and present the advantages to a distributed computing system resulting from CEDAR's separation of these layers. Regardless of the authentication method used, CEDAR establishes a secure session key, which has the flexibility to be used for multiple capabilities. We demonstrate how a layered approach to security sessions can avoid round-trips and latency inherent in network authentication. The creation of a distinct session management layer allows for optimizations to improve scalability by way of delegating sessions to other components in the system. This session delegation creates a chain of ...

Energy Technology Data Exchange (ETDEWEB)

The objective of this work group was to identify obstacles to the development of better risk management practices and performance standards in the pipeline industry. An outline of developments in pipeline risk assesment management was presented, including an update of the Risk Based Design and Assessment annex and other CSA Z662 code developments. It was suggested that progress in risk management require that acceptable levels of risk and reliability need to be defined. Environmental and safety consequence analysis was recommended, as well as failure frequency estimation and assessment of distribution systems. Guidelines for Integrity Management Programs (IMPs) were reviewed. It was noted that CSA Z662 will become mandatory for sour gas in 2005 and may become mandatory for all onshore pipelines in 2007. Operating company procedures in relation to hazards with significant consequences were discussed. It was noted that companies should assess ...

Energy Technology Data Exchange (ETDEWEB)

An experimental campaign, aiming to investigate the perturbation effects induced by fixed obstacles on turbulence measurements in airflows at the air-sea interface, was carried out at the marine platform of the Italian Navy, located in the harbour of La Spezia (North Ligurian Sea, Italy) on 28., 29., and 30. June 1994. This study was prompted by the ever-growing interest in more reliable estimates of energy, mass, and momentum exchanges between water surfaces and atmosphere, whose measurements are severely limited by the geometrical constraints of floating or fixed platforms where they are installed. Two types of meteorological instruments have been used: fast response (20 and 21 Hz) ultrasonic anemometers and fluxmeters to measure turbulent momentum, sensible, and latent heat fluxes and slow-response sensors (less than 4 Hz and sampled at a rate of 10{sup 2} Hz) to measure average wind and temperature vertical profiles in the perturbed boundary layer. Both fast- ...

Norwegian Open Research Archives (NORA)

Full Text Available

Science.gov (United States)

... entitled: In-country Pilot Activities: Reducing Emissions from Deforestation and Degradation)...

British Library Electronic Table of Contents (United Kingdom)

This paper presents a dynamic displacement influence line method for moving load identification on bridge. The finite element model of Poyang Lake continuous truss bridge-train systems is established and the dispersed modal shapes are acquired by modal analysis. Multi-axle moving train loads are identified with simulated annealing genetic algorithm by minimizing the errors between the measured displacements and the reconstructed displacements from the identified moving loads. In the identification process, the dynamic displacement influence line technique is used to calculate the time history displacement responses of the bridge to avoid solving equations of motion of the bridge repetitively. Several important parameters of the bridge-train system are discussed to investigate their effects...

International Nuclear Information System (INIS)

More important than waste generation numbers, the pollution prevention and waste minimization successes achieved at Hanford in 1993 have reduced waste and improved operations at the Site. Just a few of these projects are: A small research nuclear reactor, unused and destined for disposal as low level radioactive waste, was provided to a Texas University for their nuclear research program, avoiding 25 cubic meters of waste and saving $116,000. By changing the slope on a asphalt lot in front of a waste storage pad, run-off rainwater was prevented from becoming mixed low level waste water, preventing 40 cubic meters of waste and saving $750,000. Through more efficient electrostatic paint spraying equipment and a solvent recovery system, a paint shop reduced hazardous waste by 3,500 kilograms, saving $90,800. During the demolition of a large decommissioned building, more than 90% of the building's material was recycled by crushing the concrete for ...

Energy Technology Data Exchange (ETDEWEB)

Background: The difficulty of directly measuring cellular dose is a significant obstacle to application of target tissue dosimetry for nanoparticle and microparticle toxicity assessment. As a consequence, the target tissue paradigm for dosimetry and hazard assessment of nanoparticles has largely been ignored in favor of using metrics of exposure (e.g. ?g particle/mL culture medium, particle surface area/mL, particle number/mL). We have developed a computational model of solution particokinetics (sedimentation, diffusion) and dosimetry for non-interacting spherical particles and their agglomerates in monolayer cell culture systems. Particle transport to cells is calculated by simultaneous solution of Stokes Law (sedimentation) and the Stokes-Einstein equation (diffusion). Results: The In vitro Sedimentation, Diffusion and Dosimetry model (ISDD) was tested against measured transport rates or cellular doses for multiple sizes of polystyrene ...

Energy Technology Data Exchange (ETDEWEB)

Solar cookers offer a viable alternative to conventional cooking methods in many areas, and can be an effective tool in the fight against the deforestation and desertification that plague many developing countries. However, there have been numerous obstacles to the successful dissemination of solar cookers in the past. The purpose of this paper is to identify opportunities, review constraints and develop a marketing strategy to disseminate the Sundyne Solar Cooker (SSC) in developing countries.

International Nuclear Information System (INIS)

The working group reviewed the main difficulties foreseen in doing physics at a gamma-gamma collider. They discussed the requirements for the detector, calculated some of the signal and background rates, compared methods of measuring luminosity, looked at how to get the laser beams in, investigated ways of sweeping aside the electrons and considered ways of disposing of the used beams. No overwhelming obstacles were found but important questions still need to be answered. ((orig.)).

Energy Technology Data Exchange (ETDEWEB)

The production of retrograde amnesia (RA) upon electron-beam exposure was investigated. RA production was evaluated using a single-trial avoidance task for 10, 1, and 0.1 microsecond pulsed exposures. The dose-response curve obtained at each pulse duration showed significant RA production. The most effective dose range was 0.1-10 rad at a dose rate of 1,000,000 rad/sec. By employing a 10 rad (1,000,000 rad/s) pulse, a memory loss of the events occurring in the previous 4 sec was demonstrated. The conclusion was that the RA effect might be due to sensory system activation which provided a novel stimulus that masked previous stimuli.

British Library Electronic Table of Contents (United Kingdom)

Background, Aim, and Scope The identification and assessment of environmental tradeoffs is a strongpoint of life cycle assessment (LCA). A tradeoff made in many product systems is the exchange of potential for occupational accidents with the additional use of energy and materials. Net benefits of safety measures with respect to human health are best illustrated if the consequences avoided and health impacts induced by additional emissions are assessed using commensurable metrics. Our aim is to develop a human health impact indicator for offshore crane lifts. Crane lifts are a major cause of accidents on offshore oil and gas (O & G) rigs, and health impacts from crane lift accidents should be included in comparative LCA of O & G technologies if the alternatives differ in the use of crane li...

CERN Document Server

Strong gravitational lensing of an extended object is described by a mapping from source to image coordinates that is nonlinear and cannot generally be inverted analytically. Determining the structure of the source intensity distribution also requires a description of the blurring effect due to a point spread function. This initial study uses an iterative gravitational lens modeling scheme based on the semilinear method to determine the linear parameters (source intensity profile) of a strongly lensed system. Our 'matrix-free' approach avoids construction of the lens and blurring operators while retaining the least squares formulation of the problem. The parameters of an analytical lens model are found through nonlinear optimization by an advanced genetic algorithm (GA) and particle swarm optimizer (PSO). These global optimization routines are designed to explore the parameter space thoroughly, mapping model degeneracies in detail. We develop a ...

Science.gov (United States)

Electric utilities have been surprised by recent opposition to the construction of very-high-voltage transmission lines, which met with little resistance in the past. Concerns over health and safety factors are associated with the increase in the number of such lines, although their presence has always been an inconvenience and a hazard for those living and working in the immediate vicinity. The new lines present additional hazards due to the continuous flow of small electric currents and the charges that build up in the area of the towers and lines. The lines are also a threat to persons wearing cardiac pacemakers. There is experimental evidence from the Soviet Union and the U.S. that electric and magnetic fields at the frequencies of such power lines can have serious biological effects on growth rates and the functioning of the central nervous system. Full disclosure that possible risks are involved and the opportunity to avoid these risks is ...

British Library Electronic Table of Contents (United Kingdom)

Several challenges currently exist for rational design of functional tissue engineering constructs within the host, which include appropriate cellular integration, avoidance of bacterial infections, and low inflammatory stimulation. This work describes a novel class of biodegradable, amphiphilic polyanhydrides with many desirable protein-material and cell-material attributes capable of confronting these challenges. The biocompatible amphiphilic polymer films were shown to release laminin in a stable and controlled manner, promote neural cell adhesion and differentiation, and evade inflammatory responses of the immune system. Using high-throughput approaches, it was shown that polymer chemistry plays an integral role in controlling cell?film interactions, which suggests that these polyanhyd...

Energy Technology Data Exchange (ETDEWEB)

Calculating work-function modifications for flat-lying conjugated molecules on extended metal surfaces using density functional theory (DFT) is an extremely resource intensive task. This prevents fast screening of new molecules for their potential to optimize metal work functions for good electron or hole injection in organic electronic devices. We present a semi-classical model, which avoids that problem. This is achieved by identifying the dominant processes occurring at the interface between metal and adsorbate in the pinning-regime, which are then parameterizing their description using band-structure DFT calculations for a small training set With the resulting interdependent equations at hand, only simple gas-phase calculations are needed to predict the work-function changes induced by new molecules. The model is tested for ten molecules on three different metal surfaces, where it shows excellent agreement with photoelectron spectroscopy data on these ...

Energy Technology Data Exchange (ETDEWEB)

This study presents a dynamic analysis of a rotor supported by two turbulent flow model journal bearings and lubricated with couple stress fluid under nonlinear suspension. The dynamics of the rotor center and bearing center is studied. The dynamic equations are solved using the Runge-Kutta method. The analysis methods employed in this study is inclusive of the dynamic trajectories of the rotor center and bearing center, power spectra, Poincare maps and bifurcation diagrams. The maximum Lyapunov exponent analysis is also used to identify the onset of chaotic motion. The results show that the values of dimensionless parameters l* strongly influence dynamic motions of bearing and rotor centre. It is found that couple stress fluid improve the stability of the system when l* > 0.4 even if the flow of this system is turbulent. We also demonstrated that the dimensionless rotational speed ratios s and the dimensionless unbalance parameter ...

Energy Technology Data Exchange (ETDEWEB)

Industrial facilities offer a wide variety of design challenges to engineers, including the mechanical engineers who design the HVAC, the process, exhaust, and other required mechanical systems; the mechanical contractors who install and maintain the systems (and who also may do design work); and the owners` engineers who are responsible for the day-to-day operation of their facilities. Along with the responsibility to see that all systems function as intended is the responsibility to ensure that all worker health concerns are addressed. These include heat stress avoidance and the proper control of harmful substances. The services of industrial hygienists may be required to ensure this. These may be independent consultants or the staff members of mechanical design firms. In addition, it is not unusual for major corporations that own manufacturing plants to have staff industrial hygienists. The ...

UK PubMed Central (United Kingdom)

In a Swedish community-based program for the treatment of dental phobic patients, a clinical trial was performed among 99 severely phobic individuals with long-standing avoidance of dental treatment....Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The large number of forms and types of pump equipment in common use have different purposes and varying application requirements. This text has been prepared to bring together necessary information for those who are required to select and apply pumps in systems for all kinds of fluids and purposes. It is not a design manual. It limits the discussion of design to those factors which are necessary for an understanding of pump operation. The book contains not only descriptive information of many types of designs, but also the effect of design variation on use, economy, and reliability. Systems, an integral part of application, are discussed, so that the user of such equipment may properly select and install machines to reliably and economically satisfy his requirements. Reading of appropriate sections of the text will indicate possible problems to be avoided, and economics to be gained. The engineering design of pumps is a ...

International Nuclear Information System (INIS)

Current hydrocarbon-based energy systems, current energy consumption and the push towards the utilization of renewable energy sources, fuelled by global warming and the need to reduce atmospheric pollution are discussed. The consequences of climatic change and the obligation of Annex B countries to reduce their greenhouse gas emissions in terms of the Kyoto Protocols are reviewed. The role that renewable energy sources such as hydrogen, solar and wind energy could play in avoiding the most catastrophic consequences of rapidly growing energy consumption and atmospheric pollution in the face of diminishing conventional fossil fuel resources are examined. The focus is on hydrogen energy as a means of storing and transporting primary energy. Some favorable characteristics of hydrogen is its abundance, the fact that it can be produced utilizing renewable or non-renewable sources, and the further fact that its combustion produces three times more ...

Energy Technology Data Exchange (ETDEWEB)

This study presents a dynamic analysis of a flexible rotor supported by two porous squeeze couple stress fluid film journal bearings with non-linear suspension. The dynamics of the rotor center and bearing center are studied. The analysis of the rotor-bearing system is investigated under the assumptions of non-Newtonian fluid and a short bearing approximation. The spatial displacements in the horizontal and vertical directions are considered for various non-dimensional speed ratios. The dynamic equations are solved using the Runge-Kutta method. The analysis methods employed in this study is inclusive of the dynamic trajectories of the rotor center and bearing center, power spectra, Poincare maps and bifurcation diagrams. The maximum Lyapunov exponent analysis is also used to identify the onset of chaotic motion. The numerical results show that the stability of the system varies with the non-dimensional speed ratios, the non-dimensional ...

International Nuclear Information System (INIS)

Among others, one of the main activities in the Nuclear Engineering and Fluid Mechanics Department of the Engineering School in Bilbao, is the study of liquid metals behavior. And for this purpose the CFD code FLUENT is being used. Currently, the code is being applied to the use of Lead-Bismuth eutectic (LBE) as the coolant of an accelerator driven system (ADS) and also as the target for a neutron source. In this paper, ANSALDO's Energy Amplifier Demonstration Facility is simulated, paying attention only on the coolant. As it will be later explained, natural convection is a very important issue, because the philosophy for safety systems in nuclear devices tends to consider passive technologies. The purpose is to avoid electrical machines like pumps, so the core should remain coolable, even if there is a blackout. To get this natural circulation, heat transfer plays a main role, and as turbulence enhances the heat transfer, ...

Energy Technology Data Exchange (ETDEWEB)

A new small size gamma irradiator is being set up at Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Brazil, with a revolutionary design. The developed technology for this facility consists of continuous tote box transport system, comprising a single concrete vault, where the automated transport system of products inside and outside of the irradiator utilizes a rotating door, integrated with the shielding, avoiding the traditional maze configuration. Covering 76 m{sup 2} of floor area, the irradiator design is product overlap sources and the maximum capacity of Cobalt-60 wet sources is 37 PBq (1 MCi). The irradiator is being installed in a Governmental Institution and it will be used as a demonstration facility for manufacturers, who need an economic and logistic in-house irradiation system alternative. Also, it will be useful for supporting the local scientific community on development ...

International Nuclear Information System (INIS)

The Belgian Tihange 2 nuclear power plant went into commercial operation in 1983 producing a thermal power of 2785 MW. Since the commissioning of the plant the steam generators U-tubes have been affected by primary stress corrosion cracking. In order to avoid further degradation of the performance and an increase in repair costs, Electrabel, the owner of the plant, decided in 1997 to replace the 3 steam generators. This decision was supported by the feasibility study performed by Tractebel Energy Engineering which demonstrated that an increase of 10% of the initial power together with a fuel cycle length of 18 months was achieved. Tractebel Energy Engineering was entrusted by Electrabel as the owner's engineer to manage the project. This paper presents the role of Tractebel Energy Engineering in this project and the safety analysis program necessary to justify the new operation point and the fuel cycle extension to 18 months re-analysis of FSAR chapter 15 accidents ...

International Nuclear Information System (INIS)

Stretch-out operation mode can deepen the reactor burnup when the boron concentration is near 0 mg/L, in which the additional reactivity is introduced by the reducing of the moderator temperature and the decreasing of the load. Stretch-out is used in many nuclear power plants all over the world. The first stretch-out operation has been used for the first time in China. As a specific operation mode, which outruns the original reactor core design, the related and specialized design argument and safety analysis is required. As a consequence of the continuous or stepwise reduction of load and moderator temperature, the neurotic measurement system and the reactor control and protection system parameters should be modified specially. Based on the schedule of the electricity production, the first stretch-out operation had been carried out from March 12 to March 21 2003. It successfully avoided the overlapping between 209 and 109 ...

Energy Technology Data Exchange (ETDEWEB)

The purpose of this paper is to compare the techniques and results obtained when a general industrial or commercial building power electrical system is prepared using the US National Electrical Code{copyright} (NEC) and the International Electrotechnical Commission (IEC) Standards. The final design offer the reader the possibility of making an initial comparison and analyzation of the two methods based of their overall effectiveness (sizing, protection, co-ordination of protective devices with components etc.), safety and cost. In order to make such a comparison a specific example was developed and limited in detail to avoid complexity in this study. The power source selected will be a delta-wye utility supplied transformer feeding various load groups such as lighting and motor circuits (possibly through associated transformers). Relevant NE Code references, IEC standards, and appropriate justifications will be made at various points. Since ...

Energy Technology Data Exchange (ETDEWEB)

The significant technical and industrial aspects which have led to main coolant line (MCL) materials selection are addressed from a long term experience and operational practice point of view. They are based on the Siemens/KWU developed basic material concept for its nuclear power plants. It considers the choice of appropriate materials, the evaluation and qualification of the materials and the materials manufacturer, the use of appropriate semi-finished products, the tailoring of material and semi-finished products to the specific requirements of the various systems, the application of adequate manufacturing processes and the proof of the requirements by specifying proper tests and examinations. The main systems are assigned to safety classes in accordance with their safety relevance. Summarizing the operation time of nuclear power plants with ferritic MCL equipped by Siemens/KWU, more than 200 years of operation experience exist and no ...

International Nuclear Information System (INIS)

Full text: Research reactors have been playing a multi dimensional role in areas of nuclear fuel cycle programme, radio-isotope productions, neutron beam research etc. To ensure an efficient, smooth and safe operation of a nuclear research reactor, many reactor physics evaluations are required on routine basis. As part of reactor core management the important activities are maintaining core reactivity status, core power distribution, xenon estimations, safety evaluation of in-pile irradiation samples and experimental assemblies and assessment of nuclear safety in fuel handling/storage. In-pile irradiation requires a prior estimation of the reactivity load due to the sample, heating rate and the activity developed in it during irradiation. For the safety of the personnel handling irradiated samples the dose rate at the surface of shielded flask housing the irradiated sample should be less than 200 mR/Hr. Therefore, a proper shielding and radioactive cooling of the irradiated sample is ...

Energy Technology Data Exchange (ETDEWEB)

Green building (GB) is part of the concept of promoting sustainability. Although GB and the concept of sustainability are well studied for environmental concerns, their business rationale and related social concerns have not been fully explored or widely accepted by the parties involved in the building sector. In this study, the situation of GB market in relation to the general building market is reviewed and the business rationales of stakeholders to invest in the GB market have been investigated from the perspective of building designers. In addition, the factors that enhance the popularity of GB have been explored and the obstacles that hinder its market have been examined. The data are collected by a questionnaire survey covering building designers in Hong Kong and Singapore, the cities that are categorized as economically developed cities in Asia. After data analysis of the survey, this paper presents the findings of the business reasons for stakeholders to be ...

Scientific Electronic Library Online (English)

Abstract in english We consider the three dimensional electromagnetic inverse scattering problem of determining information about a buried coated object from a knowledge of the electric and magnetic fields measured on the surface of the earth corresponding to time harmonic electric dipoles as incident fields. We assume that the buried object is a perfect conductor that is (possibly) partially coated by a thin dielectric layer. No a priori assumption is made on the extent of the coating, i.e. (more) the object can be fully coated, partially coated or not coated at all. We present an algorithm based on the linear sampling method and reciprocity gap functional for reconstructing the shape of the scattering obstacle together with an estimate of the surface impedance of the coating.

British Library Electronic Table of Contents (United Kingdom)

Purpose - The purpose of this paper is to describe the processes and procedures utilized by Jacksonville State University's Houston Cole Library to digitize an oral history collection and provide access to it through the Library's catalog, web presence, and the state-wide digital repository initiative, Alabama Mosaic (see www.alabamamosaic.org). Design/methodology/approach - The paper is based on the Library's experiences in acquiring, digitizing, creating metadata for and making accessible a collection of oral histories. Findings - The paper describes the obstacles overcome, issues encountered, procedures established, and ramifications of the project. Practical implications - Many institutions are currently digitizing unique collections as part of repository initiatives, both institutiona...

Energy Technology Data Exchange (ETDEWEB)

The reasons for including variance-covariance information in evaluated nuclear data files are reviewed. Accomplihments and obstacles in meeting these needs are identified. The capability to develop and utilize evaluated cross-section covariance files has been largely demonstrated, but comprehensive files of soundly based covariance data remain to be evaluated and not all types of cross-section data have yet been included. The status of the ENDF-VI covariance formats is discussed. Priorities are suggested for further development. Most effort should be concentrated to fully develop the capability to estimate the nuclear data uncertainties in quantities calculated for a broad energy spectrum. 12 refs.

Energy Technology Data Exchange (ETDEWEB)

Several technological alternatives have been studied taking into consideration that one of the biggest problems of the electric power companies is to provide electric power during the peak consumption periods, which largest contribution to the increase of the demand comes from the residential sector, especially by the use of electric showers. One of the most promising alternatives is the pre-water heating system for reduced power showers, developed by Universidade de Campinas and Companhia Paulista de Forca e Luz. The goal of this system is basically to reduce demand during the peak periods, in order to avoid heavy investments by the electric power companies in generation, transmission and distribution of electric power directed to low acquisitive power customers, a sector in which the electric power price is not enough to recover such investments. The objective of this paper is to evaluate the total energy required in the ...

Energy Technology Data Exchange (ETDEWEB)

The proton beam has a unique advantage over the electron and photon beams in that it can give very high radiation dose to the tumor volume, while effectively sparing the neighboring healthy tissue and organs. For the clinical application of the proton beam, it is very important to confirm the location of the proton beam in the patient, preferentially during the treatment. It has been suggested that the range of the proton beam in the patient can be determined by measuring prompt gammas from the proton beam passage. Recently, a prototype prompt-gamma scanning system has been constructed and tested using experimental and therapeutic proton beams. The measurement results for the proton beams of 70 . 230 MeV showed that a clear correlation exists between the distribution of the prompt gammas and the proton beam range. The scanning method, however, is not suitable for the upcoming 'spot scanning' technique. The 'spot scanning' ...

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the results of research conducted during the sixteen month continuation of a program to develop rechargeable zinc-air batteries for electric vehicles. The zinc-air technology under development incorporates a metal foam substrate for the zinc electrode, with flow of electrolyte through the foam during battery operation. In this soluble'' zinc electrode the zincate discharge product dissolves completely in the electrolyte stream. Cycle testing at Lawrence Berkeley Laboratory, where the electrode was invented, and at MATSI showed that this approach avoids the zinc electrode shape change phenomenon. Further, electrolyte flow has been shown to be necessary to achieve significant cycle life (> 25 cycles) in this open system. Without it, water loss through the oxygen electrode results in high-resistance failure of the cell. The Phase I program, which focused entirely on the zinc electrode, elucidated the ...

Energy Technology Data Exchange (ETDEWEB)

This presentation discussed common mechanisms for procuring wind energy in Canada. Mechanisms included renewable portfolio standards (RPSs); offsets; tax subsidies; financial subsidies; command and control mechanisms; and request for proposals (RFPs). A layered approach is required to avoid reliance on any single mechanism. RPSs require a certain minimum percentage of energy to come from renewable sources and aim to encourage the local development of renewable energy. RPSs are market-friendly and often result in the creation of tradable renewable energy credits (RECs) used for compliance purposes. RPSs work in parallel with cap and trade, baseline, and credit and carbon tax systems. RFPs target the lowest price offering, a practice which has often resulted in lower rates of return, high attrition, and a failure to attribute market prices to green attributes. It was concluded that RPSs work with a variety of policy frameworks and encourage the ...

Energy Technology Data Exchange (ETDEWEB)

Silver zeolite is used to capture radioiodines from air cleaning systems in some nuclear facilities at the Idaho National Engineering Laboratory. It may become radioactively contaminated and/or poisoned by hydrocarbon vapors, which diminishes its capacity for iodine. Silver zeolite contains up to 38 wt% silver. A pyrometallurgical process was developed to reclaim the silver before disposing of the unserviceable zeolite as a radioactive waste. A flux was formulated to convert the refractory aluminosilicate zeolite structure into a low-melting fluid slag, with Na{sub 2}O added as NAOH instead of Na{sub 2}CO{sub 3} to avoid severe foaming due to CO{sub 2} evolution. A propane-fired furnace was built to smelt 45 kg charges at 1300C in a carbon-bonded silicon carbide crucible. A total of 218 kg (7000 tr oz) of silver was reclaimed from 1050 kg of unserviceable zeolite. Silver recoveries of 97% were achieved, and the radioisotopes were fixed as ...

International Nuclear Information System (INIS)

There has been a growing interest in new laser systems for use at mid-infra-red wavelengths, driven by requirements for a number of diverse applications. Developments in mid-IR coating technology are following three major thrusts. In the first, the potential of ion-assisted process is being exploited and the technology is already becoming well established in the optical coating industry. In the second, the benefits of using gas-phase precursors are being explored, driven by the potential of avoiding the generation of second phase inclusion in the coatings with associated reduction in laser damage threshold. Research is also addressing the use of nanocomposite materials with an engineered microstructure to produce coatings with dielectric properties of choice. This paper presents a review of progress in some of these areas with special emphasis on the comparison of the properties of materials at DF laser wavelengths. Evidence is presented which ...

International Nuclear Information System (INIS)

The design of a gaging head for a portable radionuclide X-ray fluorescence analyzer is described. The gaging head is designed as a construction unit system which enables the application of lateral reflexion geometry as well as of coaxial geometry. It is designed so that adjustment from one geometry to the other is labour and time saving. The selection of characteristic radiation is performed by a couple of Ross' differential filters. These filters are prepared by a novel technique developed by our laboratory. The filter exchange is effected by the longitudinal move of the couple of filters encapsulated in a holder. The shift of the filters is controlled by means of a triggering mechanism situated in the body of the gaging head handle. This design makes is possible to handle the gaging head during measurements with one hand. A simple interchange of the absorption filter for the transmissive filter allows the operator to avoid any unwanted shift ...

International Nuclear Information System (INIS)

Fundamentals of klystron testing is a text primarily intended for the indoctrination of new klystron group test stand operators. It should significantly reduce the familiarization time of a new operator, making him an asset to the group sooner than has been experienced in the past. The new employee must appreciate the mission of SLAC before he can rightfully be expected to make a meaningful contribution to the group's effort. Thus, the introductory section acquaints the reader with basic concepts of accelerators in general, then briefly describes major physical aspects of the Stanford Linear Accelerator. Only then is his attention directed to the klystron, with its auxiliary systems, and the rudiments of klystron tube performance checks. It is presumed that the reader is acquainted with basic principles of electronics and scientific notation. However, to preserve the integrity of an indoctrination guide, tedious technical discussions and mathematical analysis have ...

Energy Technology Data Exchange (ETDEWEB)

Conventional methods for removing metals from aqueous solutions include chemical precipitation, chemical oxidation or reduction, ion exchange, reverse osmosis, electrochemical treatment and evaporation. The removal of radionuclides from aqueous waste streams has largely relied on ion exchange methods which can be prohibitively costly given increasingly stringent regulatory effluent limits. The use of microbial cells as biosorbants for heavy metals offers a potential alternative to existing methods for decontamination or recovery of heavy metals from a variety of industrial waste streams and contaminated ground waters. The toxicity and the extreme and variable conditions present in many radionuclide containing waste streams may preclude the use of living microorganisms and favor the use of non-living biomass for the removal of actinides from these waste streams. In the work presented here, we have examined the biosorption of uranium by non-living, non-metabolizing microbial biomass thus ...

Energy Technology Data Exchange (ETDEWEB)

This work considers the problem of controlling multiple nonholonomic vehicles so that they converge to a scent source without colliding with each other. Since the control is to be implemented on simple 8-bit microcontrollers, fuzzy control rules are used to simplify a linear quadratic regulator control design. The inputs to the fuzzy controllers for each vehicle are the (noisy) direction to the source, the distance to the closest neighbor vehicle, and the direction to the closest vehicle. These directions are discretized into four values: Forward, Behind, Left, and Right, and the distance into three values: Near, Far, Gone. The values of the control at these discrete values are obtained based on the collision-avoidance repulsive forces and the change of variables that reduces the motion control problem of each nonholonomic vehicle to a nonsingular one with two degrees of freedom, instead of three. A fuzzy inference system is used to obtain ...

Energy Technology Data Exchange (ETDEWEB)

Operating the Stanford Linear Collider (SLC) at 120Hz repetition rate requires the presence of two bunches in both the electron and the positron damping ring. The {pi}-mode instability, a coupled bunch instability where the two bunches oscillate with a phase difference of 180{degrees}, had been observed in both rings with low current thresholds of 7{sup *}10{sup 9} particles per bunch. To avoid the instability, the RF system had to be operated in ways which in general reduced the cavity gap voltages and required constant operational attention. For the 1992 running cycle a passive cavity was installed and successfully tested. It is tuned to the frequency of the lower synchrotron oscillation sideband of an odd revolution harmonic. The impedance of the cavity then damps {pi}-mode oscillations very similar to the Robinson damping provided by the main RF cavities which damps O-mode synchrotron oscillations. In this report we describe the motivation ...

International Nuclear Information System (INIS)

The method of superposition of configurations was applied to the triplet sigma, pi, and delta states of HeH"+ which correlate to the separated atom states of principal quantum number less than or equal to 3. The calculations were done for internuclear separations, 0< or =R< or =65.5 a.u., on a mesh adequate for interpolation. Similar calculations on the singlet states have already been reported. The present calculations complete the accurate evaluation of the potential energy curves for this system which are required for low- and intermediate-energy collision studies. In addition to the energy eigenvalues and eigenfunctions, dipole, gradient, and radial coupling matrix elements were calculated for the sigma and pi states. Primarily, this paper presents information on the eigenvalues. The accuracy of the triplet-state calculations is comparable to that obtained for the singlet states. The similarities and differences in the pattern of ...

International Nuclear Information System (INIS)

In an effort to evaluate the feasibility of introducing computed radiography (FCR) into mass screening for lung cancer, the ability of FCR to detect nodules one cm in diameter was examined using a humanoid chest phantom. Based on the receiver operating characteristic (ROC) analysis, the detectability of FCR was compared with that of conventional radiography and photofluorography. The values of area under ROC curves were higher for FCR (0.963 for image similar to that with conventional film-intensifying screen system, image A; and 0.952 for processed image, image B) than the other two methods (0.774 for radiography and 0.789 for photofluorography). Degradation of image quality in FCR could be avoided by a wide latitude even if proper exposure techniques might not be employed. Images A and B in FCR yielded excellent delineation for nodules in the lung field and in the retrocardiac and subdiaphragmatic regions, respectively. This may have ...

International Nuclear Information System (INIS)

An attempt is made to generalize the spaces of numbers and functions in order to consider certain problems in quantum mechanics, especially in the cases, where wave functions appear which do not belong to the Hilbert space L"2. Often the Soboljev - Schwartz distributions are used but they are not always the appropriate tool because they cannot be multiplied. A modification of the definition of generalized functions PSI(x vector) is proposed by particular conditions. Such conditions imposed on the wave function of a free particle seems to be the most natural by means of physics. It appears, however, that for all spaces with a real norm these conditions are contradictory. This implies together with the extension of the space of functions, an extension of the space of numbers with so called asymptotic numbers A. The four algebraic operations - addition, subtraction, multiplication and division are defined in the set A. To avoid the contradictions between the ...

Energy Technology Data Exchange (ETDEWEB)

The /sup 252/Cf-source-driven neutron noise analysis method for obtaining the subcriticality of an assembly of fissile material from cross-power spectral densities (CPSDs) was developed to avoid some difficulties inherent in other measurement methods. This method requires measurement of frequency-dependent CPSD between a pair of detectors in or near the fissile assembly and CPSDs between these detectors and a source of correlated neutron noise from an ionization chamber containing /sup 252/Cf, also in or near the fissile assembly. Also, the auto-power spectral density of the source is required. The ratio of spectral densities is then formed and is related to the subcriticality. To date various measurements have been performed which demonstrate the usefulness of the method including measurements with single uranium metal cylinders. The experiments described here, which used coupled uranium (93.15 wt % /sup 235/U) metal cylinders separated by air, are the first ...

International Nuclear Information System (INIS)

Gadolinium removal during the first approach to criticality of TAPP-4 540 MWe reactor using mixed bed resin (strong acid cation resin and weak base anion resin) topped with strong acid cation exchange resin yielded IX column outlet pH of >6 during the first 6 h of run during which [Gd] decreased from 2.1 to 1 mg/kg. However, the main moderator system pH was between 5.0-5.5. Technical specification for pH of moderator is in the range 5.0-5.5 as long as Gd is present. This is to avoid any precipitation of Gd in the core and a pH of 5.8 or even a pH of 5.6 when carbonate is present is specified as the upper limit of the moderator system pH for this purpose. The situation of IX column outlet pH being #>=# 6 mixing with a system water having Gd results in local mixing zone pH in the range of 6- 5.4. In order to have an iso-pH regime (5-5.5) both with respect to the IX outlet as well as in the ...

UK PubMed Central (United Kingdom)

BackgroundBlindness due to trachoma is avoidable through Surgery, Antibiotics, Facial hygiene and Environmental improvements (SAFE). Recent surveys have shown trachoma to be a serious...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Short communication

UK PubMed Central (United Kingdom)

Many family physicians are considering purchasing a computer in the near future. This article explains some of the jargon of the computer industry and describes the various specifications that will...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The most developed systems for the generation of electricity from coal are the Integrated coal Gasification Combined Cycle (IGCC) and the Pressurized Fluidized Bed Combustion (PFBC) system. They both represent state-of-the-art technology and provide electric power at 41-46% LHV efficiency. However, the high level of complexity leads to lower reliability and higher costs. A simpler system, based on a coal-fired steam boiler integrated with a gas turbine, has been proposed. In such a plant, known as the externally fired combined cycle (EFCC), compressed air is heated indirectly in a heat exchanger located in the coal furnace. The hot air is then expanded in a turbine, and the exhaust is passed on to the coal furnace as preheated combustion air. Steam produced in the boiler generates additional power in a steam turbine. The exclusion of coal combustion products from the gas turbine avoids hot gas clean-up ...

Energy Technology Data Exchange (ETDEWEB)

This article presents the results of analyses of large-scale integration of wind power, photo voltaic (PV) and wave power into a Danish reference energy system. The possibility of integrating Renewable Energy Sources (RES) into the electricity supply is expressed in terms of the ability to avoid excess electricity production. The different sources are analysed in the range of an electricity production from 0 to 100% of the electricity demand. The excess production is found from detailed energy system analyses on the computer model EnergyPLAN. The analyses have taken into account that certain ancillary services are needed in order to secure the electricity supply system. The idea is to benefit from the different patterns in the fluctuations of different renewable sources. And the purpose is to identify optimal mixtures from a technical point of view. The optimal mixture seems to be when onshore wind ...

Energy Technology Data Exchange (ETDEWEB)

The hydroelectric industry's recognition of the importance of avoiding unexpected failure, or forced outages, led to the development of probabilistic, or risk-based, methods in order to attempt to quantify exposures. Traditionally, such analysis has been carried out by qualitative assessments, relying on experience and sound engineering judgment to determine the optimum time to maintain, repair or replace a part or system. Depending on the nature of the problem, however, and the level of experience of those included in the decision making process, it is difficult to find a balance between acting proactively and accepting some amount of risk. The development of a practical means for establishing the probability of failure of any part or system, based on the determination of the statistical distribution of engineering properties such as acting stresses, is discussed. The capacity-demand analysis methodology, coupled ...

Energy Technology Data Exchange (ETDEWEB)

Vehicle heating requires a substantial amount of energy. Engines in conventional cars produce enough waste heat to provide comfort heating and defogging/defrosting, even under very extreme conditions. Electric vehicles (EVs), however, generate little waste heat. Using battery energy for heating may consume a substantial fraction of the energy storage capacity, reducing the vehicle range, which is one of the most important parameters in determining EV acceptability. Water vapor generated by the vehicle passengers is in large part responsible for the high heating loads existing in vehicles. In cold climates, the generation of water vapor inside the car may result in water condensation on the windows, diminishing visibility. Two strategies are commonly used to avoid condensation on windows: windows are kept warm, and a large amount of ambient air is introduced in the vehicle. Either strategy results in a substantial heating load. These strategies are often used in ...

International Nuclear Information System (INIS)

The difficulty and unstability of the parameter estimation of mass action model for radioimmunoassay are the major obstacles to its application in routine work. A unique robust curve fitting method for the mass action model was introduced. large numbers of simulated data were generated with Monte Carlo method to compare the accuracy and robustness of the robust fitting and the least squre fitting (Marquardt method) of the mass action model. The results demonstrated that the new robusst method significantly increased the accuracy and reliability of data processing with the mass action model. It also markedly reduced the influence of outliers in the fitting of RIA data, and it was always 'convergent'. This robust method could also be applied to other mathematical models which can be transformed into high degree equations and no initial estimates are needed for curve fitting.

International Nuclear Information System (INIS)

Nano indentation analysis and transmission electron microscopy observation were performed to investigate a microstructural evolution and its influence on the hardening behavior in Fe-Cr alloys after an irradiation with 8 MeV Fe4+ ions at room temperature. Nano indentation analysis shows that an irradiation induced hardening is generated more considerably in the Fe-15Cr alloy than in the Fe-5Cr alloy by the ion irradiation. TEM observation reveals a significant population of the a0 dislocation loops in the Fe-15Cr alloy and an agglomeration of the 1/2a0 dislocation loops in the Fe-5Cr alloy. The results indicate that the a0 dislocation loops will act as stronger obstacles to a dislocation motion than 1/2a0 dislocation loops.

Science.gov (United States)

A declaration for achieving universal basic education adopted by the World Conference on Education for All in Jomtien, Thailand, as it relates to Latin America is discussed in this paper. The document then offers an examination of educational expansion in Latin America, a discussion of disproportionate educational budget cuts, and an analysis of challenges that stem from two trends: (1) the growing gap between population growth and educational expansion; and (2) low educational quality and high repetition rates. Proposals are offered for major, gradual educational reforms based on an increased level of fiscal resources, and a change in resource management responsive to economic needs. The major obstacle to implementation is argued to be the political economy of education and of adjustment. International support of local initiatives is important in achieving basic educational equity. (33 references) (LMI)

International Nuclear Information System (INIS)

The aim of this report is to describe the present situation regarding biomass utilization in small power plants, 0.5 - 20 MW fuel power. Also discussed are the most important technical, economical and environmental conditions which may prevent a fast expansion of small biomass fueled power plants for generation of district heating in smaller networks and also for electric power generation. Biofuels means a reduction of the net emission of carbon dioxide, but emission of other compounds are not very well known for this size of power plants. There are only a few biofueled power plants in Sweden and only a couple with less than 20 MW power supplied. New concepts are under development but not much have been achieved during the most recent years. 25 refs, 10 figs, 9 tabs.

International Nuclear Information System (INIS)

Radiation exposure control is one of the most important aspects in any nuclear facility . It encompasses continuous monitoring of the various areas of the facility to detect any increase in the radiation level and/or the air activity level beyond preset limits and alarm the O and M personnel working in these areas. Detection and measurement of radiation level and the air activity level is carried out by a number of monitors installed in the areas. These monitors include Area Gamma Monitors, Continuous Air Monitors, Pu-In-Air Monitors, Criticality Monitors etc. Traditionally, these measurements are displayed and recorded on a Central Radiation Protection Console(CRPC), which is located in the central control room of the facility. This methodology suffers from the shortcoming that any worker required to enter a work area will have to inquire about the radiation status of the area either from the CRPC or will get to know the same directly from the installed only after entering the area. ...

Energy Technology Data Exchange (ETDEWEB)

The high voltage/high power DC-cathode power supply for the Gyrotron Test Facility at the Forschungszentrum in Karlsruhe consists of a 12-pulse thyristor star-point-controller, a 130 kV capacitor-bank followed by a tetrode regulator. Originally designed for 80 kV/30 A CW (continous-wave) operation, its operating regime has been extended in line with gyrotron development to pulses of 65 kV/45 A/3 min and more recently to 65 kV/80 A/10 s without any changes to the main load bearing components (thyristors, transformers or power tetrode). This allows testing of gyrotrons in the 0.5 MW (CW), 1 MW (3 min) and 2 MW (10 s) output power range. The paper describes the system, its operation and some critical aspects of the last upgrade, such as the issue of harmonics in the 20 kV distribution mains-grid, the dynamic response of the thyristor-controller and the avoidance of microwave parasitic oscillations in the high power tetrode (a CQK-200-4, developed ...

Energy Technology Data Exchange (ETDEWEB)

In recent years, several larger geothermal heat pump plants for offices or commercial areas have been designed and built in the central region of Germany, mainly in the Rhein-Main area. Systems with borehole heat exchangers (BHE; in the USA the term Vertical Loop is commonly used) as well as with shallow geothermal doublets (groundwater wells) are operational. New solutions had to be found to adapt the technology to certain site constraints, and innovative components such as thermally-enhanced grouting material have been used. This paper reviews the early development of Ground Source Heat Pumps (GSHP) for commercial buildings, gives details on a number of recent plants and discusses problems that arose during their realisation: UEG Wetzlar, a building with chemical laboratories and one of the first examples of direct cooling from BHE; DFS Langen (German Air Traffic Control Headquarters), with 154 BHE for heating and cooling, operating without antifreeze; Baseler ...

Energy Technology Data Exchange (ETDEWEB)

Canadian oilfields are a prime breeding ground for talent, technology and industrial management. This paper described how Canadian talent was recognized in 2001 for three major projects which included a cold-ocean production platform in the Sea of Okhotsk in Siberia, a mountain pipeline project in South America, and an in-situ underground extraction technology in the oilsands of Alberta. The cold-ocean production platform project was recruited by Sakhalin Energy Investment Co., an international consortium originally led by Marathon Oil Co which is now led by Royal Dutch Shell. The oil production platform is stationed 16 kilometres offshore of Sakhalin Island in the Sea of Okhotsk. Sakhalin Energy bought and converted the Molikpaq, an innovative platform made in the 1980s for the Beaufort Sea by Gulf Canada Resources Ltd. The second project included Calgary's Hydroconsult EN3 Services Ltd. which was responsible for the construction of the 940-km GasAtacama 24-inch diameter ...

Energy Technology Data Exchange (ETDEWEB)

During the previous 9 months the major part of the Fusion-FEM has been constructed. The 2 MV Insulated Core Transformer, the electron gun, the accelerator, the focusing lenses and the undulator have been tested on-site. In the present - temporary - set-up, the electron beam line consists of a 12 A, 80 keV thermionic electron gun, a 2 MeV dc accelerator, beam transport optics, the undulator and a collector. The gun is mounted in the high voltage terminal, which is now at -2 MV, and the undulator and mm-wave system am at ground potential outside the SF{sub 6}-filled pressure tank. This so-called inverse set-up allows easy access to the larger part of the beam line, the undulator and the mm-wave system, which is important in the conditioning phase. The decelerator and depressed collector am not yet installed. The design of the electron beam line has been optimised using the GPS particle-tracking code and the TOSCA code. The TOSCA code is used for ...

Energy Technology Data Exchange (ETDEWEB)

The objective of this project is to eliminate three closely inter-related barriers to oil production in Alaska through the use of a geographic information system (GIS) and other information technology strategies. These barriers involve identification of oil development potential from existing wells, planning projects to efficiently avoid conflicts with other interests, and gaining state approvals for exploration and development projects. Each barrier is the result of either current labor-intensive methods or poorly accessible information. This project brings together three parts of the oil exploration, development, and permitting process to form the foundation for a more fully integrated information technology infrastructure for the State of Alaska. This web-based system will enable the public and other review participants to track permit status, submit and view comments, and obtain important project information online. By ...

UK PubMed Central (United Kingdom)

Background:The manufacturers of oral bisphosphonates (alendronate, risedronate) recommend avoiding use of these drugs in patients with renal impairment. However, many patients who...Full Text Available

UK PubMed Central (United Kingdom)

The long-term goal of nuclear transfer or alternative reprogramming approaches is to create patient-specific donor cells for transplantation therapy, avoiding immunorejection, a major complication in...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

In this paper, we present an iterative filtering method to estimate the background of noisy spectroscopic data. The proposed method avoids the calculation of the average full width at half maximum (FWHM) of the whole spectrum and the peak regions, and it can estimate the background efficiently, especially for spectroscopic data with the Compton continuum.

UK PubMed Central (United Kingdom)

During the past decade idiopathic venous thromboembolism has become a separate entity, a chronic illness which has required prolonged anticoagulation and other prevention strategies to avoid recurrences....Full Text Available

Energy Technology Data Exchange (ETDEWEB)

It is urged that the lesson of gauge invariance in quantum electrodynamics implies the irrelevance of `Schwinger term` difficulties in current algebra. The divergence equations of Veltman form the basis of a gauge-variation formalism in which these questions are avoided. (author). 9 refs.

Science.gov (United States)

The vibrational states, absorption energies, and diffusions of H in Pd and Pd1-xAgx(0Pd-Ag alloys should avoid the Ag-rich areas.

International Nuclear Information System (INIS)

Based on a detailed analysis of the inter-relationship in the current, voltage, electromagnetic torque and ratio of the difference between the speed of rotor and the speed of rotary magnetic field to the later in the motor, the root cause was point out, which leads to the protection fuses' failure of the motor in the starting stage, which drives the turbine-generator set to rotate at low speed before its startup. Two solutions to avoid the situation are proposed, too. (authors)

British Library Electronic Table of Contents (United Kingdom)

The purpose of this paper is to describe a technique of forced surgical rotation of the mandible used in skeletal Class II patients with deep bite and prominent chin. Posterior occlusal composite onlays combined with preoperative orthodontic treatment without anterior intrusion increase the posterior rotational component of the surgical mandibular advancement, when removed during operation. This manoeuvre allows for the surgical closure of the posterior open bite, while anteriorly the deep bite is opened. This technique avoids bimaxillary rotation surgery with dorsal impaction in mild to moderate cases. In any case, a chin setback osteotomy with compromised aesthetics can be avoided.

Energy Technology Data Exchange (ETDEWEB)

Problems and solutions in the diagnosis and operative treatment were clarified by retrospective evaluation of cases of intramedullary tumor in which MRI and surgery had been performed. The subjects were 16 patients (21-75 years old, mean age: 45 years) whose tumor was surgically removed between 1991 and 1998. MRI was performed preoperatively, and T1-weighted images, T2-weighted images, and enhanced images were obtained. Angiography was also performed in some cases. The histological diagnosis based on the MRI findings before surgery were compared with the pathological diagnosis after the operation. In 9/16 cases (56%), the preoperative histological diagnosis based on the MR images was the same as the pathological diagnosis after the operation. In 8 of the 11 cases (73%) whose images showed clear tumor margins and well shaped the tumor, the tumors were completely removed. The concordance rate between the pathological diagnosis during and after the operation was 67%. Spinal cord ...

International Nuclear Information System (INIS)

The decision of the United Kingdom to adopt a policy of solidification of high level waste had led to renewed interest in vitrification. The HARVEST process chosen is an adaptation of the FINGAL concept developed at Harwell 15 years ago. Because of certain changes in engineering design and differences in the composition of the waste, additional chemical engineering data are required for HARVEST. The new inactive pilot plant has been built to provide this information. Its size is virtually full-scale and batches of glass up to 1 tonne can be manufactured in vessels of diameter up to 750mm. Five glass-making runs have been carried out. Attention has concentrated on the performance of the off-gas system which employs wet methods. Carry-over of solids occurs, primarily as a result of physical entrainment. The carry-over of synthetic fission products is improved from 2.5 to 0.1% by directing the feed down the vessel walls. Most of the entrained solids is caught in the ...

International Nuclear Information System (INIS)

The assessment of greenhouse gas impacts in the US shows that against a baseline gasoline vehicle, the impact of including the full fuel cycle generally reduces the relative advantages of alternative transportation fuels. While a switch to diesel is estimated to save 30% as compared to gasoline, the savings from natural gas/LPG are (around 20%), for ethanol from corn (8%) and for battery electricity vehicles using power from coal (6%) are much smaller. This is largely due to the use of LCA rather than end-use comparisons. However, the results also show that there would be large savings from the use of ethanol from fuel cells using methanol (39%) or natural gas (50%), while ethanol from wood in a conventional engine appears to have the greatest savings (63%). In external costs of motor vehicle use, analysis results were presented for both air pollution and energy security impacts (including SPR, military expenditures, macro-economic costs and pecuniary costs) as well as water pollution, ...

International Nuclear Information System (INIS)

The study of tropospheric kinetics underlies global change because key greenhouse gases are photochemically active. Modeling of tropospheric chemistry on a global scale is essential because some indirect greenhouse gases are short-lived and interact in a non-linear fashion. It is also extremely challenging, however; the global change grid is extensive in both the physical and temporal domains, and critical lower atmospheric species include the organics and their oxidized derivatives, which are numerous. Several types of optimization may be incorporated into kinetics modules to enhance their ability to simulate the complete lower atmospheric gas phase chemical system. (1) The photochemical integrator can be accelerated by avoiding matrix and iterative solutions and by establishing families. Accuracy and mass conservation are sacrificed in the absence of iteration, but atom balancing is restorable post hoc. (2) Chemistry can be arranged upon the ...

Energy Technology Data Exchange (ETDEWEB)

Two-phase flow in horizontal parallel channels has been experimentally investigated under fuel cell related operating conditions. Pronounced hysteresis is observed in the pressure drop versus flow characteristic curve when starting from either flooded or dry conditions. When gas is introduced into channels initially filled with water (flooded initial condition), both gas and liquid tend to flow predominantly in one channel at low gas or liquid flow velocities. As the gas flow velocity increases, even distribution of gas and liquid flow in both channels is observed, accompanied with a sudden decrease in the pressure drop. On the other hand, even gas and liquid flow distribution between both channels is found at comparatively lower gas flow velocities when starting with dry-gas flow conditions with liquid introduced into channels filled with gas (stratified flow regime). The flow regimes of this system are visualized in plots of the pressure drop against gas and ...

International Nuclear Information System (INIS)

There are several concerns which bring to consider natural gas as a viable alternative to liquid fuels in transport. First, natural gas allows the curbing of global pollution in this steadily growing industry. Indeed, decoupling greenhouse gas emissions from transport growth has become a major issue in tackling climate change. Second, a more extensive use of natural gas would relieve city air quality, which is presently at levels harmful of human health. Nonetheless, this is just one side of the coin. The other side entails building a refuelling station network, and this carries financial requirements. The financing fraction holds a pivotal role in deciding whether natural gas for automotive purposes is an efficient solution. The final aim of this work is, therefore, to compare the natural gas advantages, stemming from avoided global and local emission, with the economic rationale of engaging in supplementary model network investments. A system ...

Energy Technology Data Exchange (ETDEWEB)

This paper reported on a new cutting mechanism that cuts fresh wood into small pieces instead of wood chips in order to avoid the problem of fermentation that occurs in storage. The prototype cutting device performs a gradual and oblique cut. It consists of a large auger in which a knife is inserted on the outer edge of the helicoid. Tree trunks up to 20 cm in diameter are fed perpendicularly into the machine and are pushed along the axis where slices are cut off against a fixed sharp-edged counter blade. The cylinder enclosing the auger is the main frame of the machine, and is closed at one end, where a heavy flywheel delivers the energy coming from the tractor's power take-off (PTO). The wood pieces ranging in length from 4 to 19 cm exit through the opposite end. The auger is 700 mm in diameter with a 300 mm pitch spacing. The logs are pushed into the machine by counter-rotating rollers placed in the feed funnel. Tests were conducted to determine the ...

Energy Technology Data Exchange (ETDEWEB)

As an interim report on the study on vibration of transmission lines when gust is blowing, this paper introduces events of confused and other contacts between transmission lines, photographing of transmission line vibration, physical measurement on transmission line response, and development of simulation software. Events of confused contacts of high-voltage transmission lines with overhead ground wires have the following common conditions: gust blows nearly perpendicularly to the line direction; no obstacles exist in upwind directions; the wind blows upward or downward against high-voltage transmission lines; and size of the high-voltage transmission lines is 25 mm{sup 2}. According to photographs of transmission line vibration, it appears that gust caused a high-voltage transmission line on the upwind side to jump resulting in confused contact with the overhead ground wire. The physical measurement uses such devices as an image recording device, an anemometer, a ...

International Nuclear Information System (INIS)

Experimental observations related to the initiation of plastic deformation in metals and alloys irradiated with fission neutrons have been analyzed. The experimental results, showing irradiation-induced increase in the upper yield stress followed by a yield drop and plastic instability, cannot be explained in terms of conventional dispersed-barrier hardening because (a) the grown-in dislocations are not free, and (b) irradiation-induced defect clusters are not rigid indestructible Orowan obstacles. A new model called 'cascade-induced source hardening' is presented where glissile loops produced directly in cascades are envisaged to decorate the grown-in dislocations so that they cannot act as dislocation sources. The upper yield stress is related to the breakaway stress which is necessary to pull the dislocation away from the clusters/loops decorating it. The magnitude of the breakaway stress has been estimated and is found to be in good agreement with the measured ...

Science.gov (United States)

The study surveyed urban women's use of information media and drew attention to the implications for women in leadership positions and non-formal education. A questionnaire containing structured and unstructured items was administered to 300 women resident at Nsukka urban town Enugu State, Nigeria. One hundred and twenty-five usable copies were used for the data analysis. The findings show that oral media are the most popular among women irrespective of level of education and type of occupation. The level of education influenced the use of radio and television. Popular radio and television programmes among women include newscasts, socio-cultural programmes, music and drama. Problems hindering women's use of radio and television include time constraint, poor reception, poor condition of available sets and lack of money for repairs among others. Based on these findings the implication for the achievement of the Universal Basic Education (UBE) objectives with reference to non-formal ...

Energy Technology Data Exchange (ETDEWEB)

Our inability to associate distant regulatory elements with the genes that they regulate has largely precluded their examination for sequence alterations contributing to human disease. One major obstacle is the large genomic space surrounding targeted genes in which such elements could potentially reside. In order to delineate gene regulatory boundaries we used whole-genome human-mouse-chicken (HMC) and human-mouse-frog (HMF) multiple alignments to compile conserved blocks of synteny (CBS), under the hypothesis that these blocks have been kept intact throughout evolution at least in part by the requirement of regulatory elements to stay linked to the genes that they regulate. A total of 2,116 and 1,942 CBS>200 kb were assembled for HMC and HMF respectively, encompassing 1.53 and 0.86 Gb of human sequence. To support the existence of complex long-range regulatory domains within these CBS we analyzed the prevalence and distribution of chromosomal aberrations ...

Energy Technology Data Exchange (ETDEWEB)

In the past, organic substance is generally deemed as electrical insulator, but in recent years, molecular crystals and polymers showing electroconductivity like metal were synthesized and even those showing superconductivity have appeared. These materials are called organic metals or synthetic metals and have peculiar solid state physical properties. Examples of real application of organic electroconductive materials are becoming available, but in this article, a chip type aluminum solid electrolytic capacitor using polypyrrole is introduced. There are four kinds of capacitors including ceramic capacitors and aluminum electrolytic capacitors, etc. The aluminum electrolytic capacitor is most retarded than any other type of capacitor in introducing its chip type since its use of electrolytic solution becomes an obstacle. Polypyrrole synthesized by electrolytic polymerization through anode oxidation of pyrrole has good stability and high electroconductivity. ...

Science.gov (United States)

Experiences with weight stigma negatively impact both psychological outcomes (e.g., body dissatisfaction, depression) and behavioral outcomes (e.g., dieting, exercise). However, not everyone is equally affected by experiences with weight stigma. This study examined whether internalized societal attitudes about weight moderated the impact of weight stigma. Adult participants (n = 111) completed measures of experiences with weight stigma, as well as two indexes of internalized societal attitudes (the moderators): Internalized anti-fat attitudes and internalization of societal standards of attractiveness. Psychological outcomes included self-esteem, body dissatisfaction, drive for thinness, and bulimic symptoms; behavioral outcomes included avoidance of exercise and self-reported exercise behavior. Weight stigma was positively correlated with body dissatisfaction, drive for thinness, and bulimic symptoms, and was negatively correlated with state and trait self-esteem. ...

International Nuclear Information System (INIS)

Full text: Radiotherapy treatment planning (RTP) relies heavily on medical imaging. Until recently, the most important planning tool was the treatment simulator. The kilovoltage radiographic capabilities in a treatment simulator enabled the boundaries of treatment fields to be visualized with respect to bony anatomic landmarks. Perhaps the most important advance in treatment planning in recent years is the ability to visualize the passage of the beams with respect to a more accurate geometrical representation of the tumor and other soft tissue structures. This 'virtual simulation' uses a computer-based representation of a patient to determine the extent of the disease and the location of radiation sensitive normal tissue. Computer tomographic (CT) imaging produces a high-resolution three-dimensional representation of anatomy that can be correlated with other image sets such as magnetic resonance images (MRI) of function. Positron emission tomographic (PET) imaging is beginning to be ...

Energy Technology Data Exchange (ETDEWEB)

Minimally invasive treatment for small renal cell carcinoma (RCC) can be necessary in selected patients and, anyway, is desirable. In situ ablation techniques, including RFA, have been developed. The aim of this study is to evaluate the feasibility, safety and short-term local effectiveness of percutaneous US-guided RFA in a small series, as well as mid-term patient outcome. Thirteen patients with a total of 18 tumors (17 small lesions, 35 mm in size or less, and a larger one, 75 mm in size) underwent 19 RFA sessions. Seven patients had a solitary kidney, and three suffered from VHL disease, too. We treated four lesions in a patient with a bilateral tumor. In another patient, three lesions were ablated. Seventeen tumors were RCC; one was a metastasis from lung cancer. Eight lesions were parenchymal, six exophytic, two parenchymal/exophytic, one parenchymal/central and one central. A monopolar RF system with multitined expandable electrode needles was used. The ...

Energy Technology Data Exchange (ETDEWEB)

In order to apply chemical-looping combustion to a practical power plant, carbon deposition on the solid particle is one of the key problems to be overcome. Six kinds of solid particles were examined to clarify the kinetic behavior of carbon deposition. The effects of the solid composition, feed gas composition, and reaction temperature on carbon deposition were investigated by thermogravimetrical reactor on the basis of NiO/YSZ particle. From the viewpoints of both reactivity and resistance against carbon deposition, the particle of NiO mixed with YSZ (i.e., yttria-stabilized zirconia) was found to be a good candidate for chemical-looping combustion. It has been observed that carbon deposition could be completely avoided with very low concentration of water vapor. By means of a proposed model, the condition that carbon deposition would be avoided was identified. 12 refs., 8 figs., 2 tabs.

Energy Technology Data Exchange (ETDEWEB)

In this paper, the design of large thin PIN detector with a membrane stress avoidance configuration is proposed, and the related device fabrication process is developed. Ultra-thin PIN detector {approx} 1.13 cm{sup 2} in area is fabricated on a thin ( {approx} 35{mu}m) silicon membrane, and characterized. Detector performance improvement has been successfully demonstrated. With the membrane stress avoidance design, the improved detector exhibits a leakage of 6nA, which is at least 5 times lower than that of detector of identical junction area. The new detector features a full depleted capacitance of 110 pF, and a FWHM of 40.86 keV energy resolution for 5.486 MeV alpha particle spectrography.

Science.gov (United States)

The Defense Advanced Research Projects Agency (DARPA) inaugurated a program addressing research and development for an Exoskeleton for Human Performance Augmentation in FY!2001. A team consisting of Oak Ridge National Laboratory, the prime contractor, AeroVironment, Inc., the Army Research Laboratory, the University of Minnesota, and the Virginia Polytechnic Institute has recently completed an 18-month Phase I effort in support of this DARPA program. The Phase I effort focused on the development and proof-of-concept demonstrations for key enabling technologies, laying the foundation for subsequently building and demonstrating a prototype exoskeleton. The overall approach was driven by the need to optimize energy efficiency while providing a system that augmented the operator in as transparent manner as possible (non-impeding). These needs led to the evolution of two key distinguishing features of this team's approach. The first is the ...

Energy Technology Data Exchange (ETDEWEB)

Polychlorinated dibenzo-p-dioxins and dibenzo-furans form a family of more than 200 compounds which are relatively stable in the biosphere and tend to accumulate in the human body. The tetra- to hexa-chlorinated dioxins and furans are considered highly toxic. To facilitate the assessment of the total toxicity of dioxin and furan mixtures, the estimated toxic effects of the individual compounds relative to the 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD) were introduced as Toxic Equivalent Factors which yield, when multiplied with the respective concentrations, the Toxic Equivalent (TE) of the mixture. Toxic dioxins and furans are unintentionally formed in a number of industrial combustion processes such as waste incineration and iron ore sintering, in the chemical industry and in household heating. To keep the emissions as low as possible, off-gas clearing systems for the collection of dioxins and furans are increasingly prescribed by the authorities. In addition, ...

International Nuclear Information System (INIS)

The use of absorbable polyglactin 910 mesh (Vicryl) is described in a case of Ewing's sarcoma of the pelvis. An operation was performed to hold the small bowel and colon out of the pelvis for a temporary period during which radical radiotherapy was delivered. The mesh allowed the temporary displacement of bowel and obviated bowel radiation morbidity. (author).

Energy Technology Data Exchange (ETDEWEB)

This paper is concerned with methods of limiting the build-up of transient voltages between sheath and armor in long armored power cables. Calculations by a frequency dependent cable model demonstrate that this voltage can be efficiently limited to an acceptable level by introducing sheath-armor bondings at regular intervals, or by using a semiconductive sheath-armor interlayer. The paper investigates the required minimum length between bondings, as well as the required conductivity of the sheath-armor interlayer if the use of bondings is to be avoided.

Energy Technology Data Exchange (ETDEWEB)

As waste disposal methods and long-term precautionary care of the environment are closely related, disposal of non-avoidable and intractable residual products is to be viewed primarily from a safety angle. Also, thermal processes airm mainly at treatment, not utilization. 'Safety' in this context addresses both the environmental compatibility of the products and the process itself. In other words, only mature techniques (i.e., safe, proven ones) are employed. (orig.)

International Nuclear Information System (INIS)

The possibility of using Direct Flow Control (DFC) to avoid catastrophic accidents due to containment breaches in chemical plant is discussed. Recommendations are made for locating fluidic elements, and the effectiveness of simple DFC protection is analysed. More powerful methods of protection are outlined using spin diversion and the complementary properties of fluidic and conventional valves are exploited. (author).

Energy Technology Data Exchange (ETDEWEB)

It is shown that the existence of faster-than-light signals (tachyons) would imply the existence (and detectability) of a privileged inertial frame and that one can avoid all problems with reversed-time order only by using absolute synchronization instead of the standard one. The connection between these results and the EPR-paradox is discussed.

Energy Technology Data Exchange (ETDEWEB)

The preliminary results of a feasibility study of nighttime and/or daytime accelerated ventilation for reducing or even avoiding air conditioning energy consumption in commercial buildings, is presented. The first part of the study is based on computerized simulations and in-situ experimentations which are described. The second part is aimed at determining technological limitations to the various components and optimizing building environmental quality in terms of energy conservation, acoustics and air quality

Energy Technology Data Exchange (ETDEWEB)

The relativistic motion of an electron is numerically analyzed in a tokamak having macroscopic magnetic turbulence. Stochasticity induced by the relativistic motion overwhelms the phase averaging effect, which provides a tokamak with an effective loss mechanism for the avoidance/suppression of runaway electron generation at a major disruption. On the other hand, electrons in the KAM (Kolmogorov-Arnold-Moser) region will be observed as a runaway snake. (author)

Energy Technology Data Exchange (ETDEWEB)

A new procedure for an efficient and sparing cleaning procedure of turbines was developed. The procedure uses cleaning and passivation chemicals that solve effectively and homogeneously salt and ferrous oxide coatings from turbines, avoiding attacks from corrosion, plugging and unbalances. In several high-pressure and condensation turbines the cleaning procedure has been already put into practice. (orig.)

International Nuclear Information System (INIS)

Despite successful reduction of the general lead exposure, this heavy metal is still a matter of public concern due to the fact that associations with intellectual impairment or delayed puberty are found to correlate with very low lead blood concentrations. Lead in tap water is still an important contribution to lead exposure which may cause health risk for infants. Therefore, lead pipes should be completely sanitated by exchange against pipes made from more healthy materials. (orig.)

International Nuclear Information System (INIS)

It is desirable to avoid vibration problems by following appropriate guidelines and specifications at the design stage. Accordingly, design specifications were developed to prevent tube failures due to vibration in nuclear steam generators and liquid heat exchangers. These specifications are outlined in this report. (author). 14 refs., 2 figs.

International Nuclear Information System (INIS)

The high-frequency precessional mode of a hot-electron-stabilized magnetic configuration has previously been shown to be stable in a window of core-plasma mass. Under conditions of frequency matching, the resulting stable negative-energy precessional wave can be destabilized by coupling to positive-energy shear-Alfven waves. Coupling is avoided when the hot-electron precession frequency exceeds the core-plasma ion gyrofrequency.

Energy Technology Data Exchange (ETDEWEB)

This report summarizes activities of the Amarillo National Resource Center for Plutonium during the quarter. The report describes the Electronic Resource Library; DOE support activities; current and future environmental health and safety programs; pollution prevention and pollution avoidance; communication, education, training, and community involvement programs; and nuclear and other material studies, including plutonium storage and disposition studies.

Energy Technology Data Exchange (ETDEWEB)

On 7 May 2009, the Ministry of the Environment set up a working group to evaluate the possible use of biodegradable waste and other biodegradable material flows for energy production and obstacles to promoting their use in the whole production cycle. The deadline for the working group was 31 January 2010. According to its mandate, the working group had to make proposals for the measures needed to promote the energy use of biodegradable waste in order to fulfil the targets of the Government Foresight Report on Long-term Climate and Energy Policy. The working group proposes thirteen measures to be put into operation so that the investments aimed at the energy use of biodegradable waste would grow significantly from the present level. The most important measure is a full ban on depositing biodegradable waste in landfills. The working group sees that the reduction of greenhouse gas emissions from landfills should, in any case, be made more effective and that the ...

Science.gov (United States)

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Energy Technology Data Exchange (ETDEWEB)

A major obstacle prohibiting the use of microwaves for soil disinfection and disinfestation is the large amount of energy required to obtain sufficient results. The present work presents an experimental study of the effect of initial soil temperature and soil moisture on energy consumption by application of microwaves for soil disinfection. All experiments were carried out by using a microwave generator of a nominal power output of 900 W. The ultra-high-frequency field (2450{+-}2 MHZ) was produced by a magnetron tube and channelled through a metal waveguide. The output opening of the waveguide was placed directly on the soil surface. It was found that a soil with 15% moisture content (w.b.) and an initial temperature of 20degC requires energy to be heated at a depth of 10 cm up to 61degC which is 3.2 times more than the energy required to heat the soil up to 5 cm depth at the same initial temperature. In general, the conversion of electric energy to useful ...

Science.gov (United States)

Based on the view that major changes in the social and economic context in the United States require major policy changes related to early childhood education, this paper examines the factors supporting public policy changes and how advocates for change in early childhood education might incorporate effective strategies. The paper is presented in two parts. Part 1 reviews the research on state policy settings and the factors that tend to support policy change. This part focuses attention on the ways that state policymakers appear to learn from what is going on elsewhere and incorporate new ideas into their policy agendas. Several strategic implications for advocates of policy change are presented, such as brainstorming a list of potential obstacles to the introduction of a policy innovation or shaping the debate so the public will support change. Part 2 of the paper takes these general strategic implications and considers their relevance to efforts to achieve ...

Energy Technology Data Exchange (ETDEWEB)

Austenitic stainless steel (18% Cr, 12% Ni, Mo gradation between 0,06 to 3,6%) had been solution nitrided. By step-by-step removing, the samples could be prepared with various surface contents of nitrogen from 0.04 to 0.42%. In two test series the influence of nitrogen had been determined. The susceptibility against pitting corrosion of these samples had been tested by the chronopotentiostatical method. For the investigated steel composition and the used corrosion system there is no influence of molybdenum on the effectiveness of nitrogen. The effectiveness of nitrogen can be described by the factor 25 in the PRE. By the investigation of the surfaces with the XPS analysis, it could be shown that the passivation and the pit nucleation is influenced by nitrogen. In these ranges NO{sub x}, NH{sub x}, and NH{sub z}-spectra have been detected. Bound Mo was found in steels containing molybdenum. It is assumed that the repassivation mechanisms of N and Mo work ...

CERN Document Server

This paper presents an uplink capacity analysis and interference avoidance technique for a femtocell based two-tier DS-CDMA network using shared spectrum. Assuming randomly distributed macrocell users and femtocell base stations (BS), we evaluate a network-wide area spectral efficiency metric called the operating contour (OC) defined as the feasible combinations of the average macrocell users and femtocell BS per cell-site that meet a target outage constraint $\\epsilon$. A contribution of this work is an accurate characterization of the uplink outage probability taking cross-tier power control, path-loss and shadowing effects into account. We show that a time-hopped CDMA physical layer coupled with sectorized receive antennas shows dramatic performance improvements in both light and heavily loaded two-tier networks, relative to a split spectrum two-tier network with omnidirectional femtocell antennas. These results provide insights into design of robust shared ...

Energy Technology Data Exchange (ETDEWEB)

Use of hydrogen in large scale applications is more usual than public is mentioning normally. Nevertheless reserve against hydrogen can be observed up to highest level decision-makers. Possibly a main reason can be found and eliminated by fixing: Some spectacular accidents happened in the past and found great interest. The publication of impressive accidents and the follow up of the events course was very carefully. The research in finding causalities in former decisions and follow up was not in the interest of some people or institutions. Important facts are even not noticed by insiders, but would have been very important for future decision makings and public acceptance of new applications. It will be demonstrated in three historical examples. Much more examples would be available and each one could help to find new applications for a saver and effective use of hydrogen in power supply. Awaking from new reserves could be avoided. Additional a safer handling would ...

Energy Technology Data Exchange (ETDEWEB)

The effectiveness of Noveko's antimicrobial filter was evaluated after 16 months of exposure to commercial swine production. The experiment involved the use of a scaled model of a commercial swine facility consisting of 2 small chambers connected by a duct containing the filters. A 5 kg naive pig was placed in the reception chamber for a period of 6 hours after aerosolization with porcine reproductive and respiratory syndrome virus (PRRSV). Blood samples from pigs were collected before and after aerosolization to test for the presence of PRRSV RNA. Only blood samples were tested for PRRSV antibodies by IDEXX 2XR ELISA. None of the 9 pigs tested were found to be infected. The study showed that the technology used to integrate the antimicrobial agent into the filter fibers allows the filter combination to withstand extreme weather and endure commercial swine production for at least 16 months, and can maintain its effectiveness to avoid airborne transmission ...

International Nuclear Information System (INIS)

Acute pneumothorax is a frequent complication after percutaneous pulmonary radiofrequency (RF) ablation. In this study we present three cases showing delayed development of pneumothorax after pulmonary RF ablation in 34 patients. Our purpose is to draw attention to this delayed complication and to propose a possible approach to avoid this major complication. These three cases occurred subsequent to 44 CT-guided pulmonary RF ablation procedures (6.8%) using either internally cooled or multitined expandable RF electrodes. In two patients, the pneumothorax, being initially absent at the end of the intervention, developed without symptoms. One of these patients required chest drain placement 32 h after RF ablation, and in the second patient therapy remained conservative. In the third patient, a slight pneumothorax at the end of the intervention gradually increased and led into tension pneumothorax 5 days after ablation procedure. Underlying bronchopleural fistula along ...

Energy Technology Data Exchange (ETDEWEB)

Aqueous mineral carbonation is a potentially attractive sequestration technology to reduce CO2 emissions. In this paper, the energy consumption and costs of this technology were assessed using either wollastonite (CaSiO3) or steel slag as feedstock. The major energy-consuming process steps were found to be the grinding of the feedstock and the compression of the CO2. Within ranges of experimentally investigated process conditions, optimum energetic CO2 sequestration efficiencies were 79 and 74% for wollastonite and steel slag, respectively. It was shown that the energetic performance for both feedstock might be improved up to >90% by e.g. further grinding of the feedstock and reducing the amount of process water applied. At energetically optimized process conditions, a preliminary cost estimate was made of 93 and 66 euro/ton CO2 avoided for wollastonite and steel slag, respectively (sequestration costs excluding possible capture). For wollastonite, major ...

International Nuclear Information System (INIS)

The reduction of emission from power plants of the public power industry inevitably leads to more and more residual products being obtained which require utilization. Traditionally, the building and building materials industry as well as, for a number of years, the gypsum industry have been the main customers processing these residual materials. To avoid having to tip them at landfills that are in short supply already, further uses are sought; so, for instance, in farming to ameliorate soil and fertilize plants. Relative to this subject, proposals are already available which are presented as lectures at the conference and discussed, together with practical knowledge and new investigation results. (BBR).

International Nuclear Information System (INIS)

Two avowable quantum communication schemes are proposed. One is an avowable teleportation protocol based on the quantum cryptography. In this protocol one teleports a set of one-particle states based on the availability of an honest arbitrator, the keys and the Einstein-Podolsky-Rosen pairs shared by the communication parties and the arbitrator. The key point is that the fact of the teleportation can neither be disavowed by the sender nor be denied by the receiver. Another is an avowable quantum secure direct communication scheme. A one-way Hash function chosen by the communication parties helps the receiver to validate the truth of the information and to avoid disavowing for the sender.

British Library Electronic Table of Contents (United Kingdom)

Titanate nanotubes were hydrothermally synthesized and their adsorption performances for lead(II) ion removal were studied. The results showed that titanate nanotubes ruptured in the adsorption process resulting in two distinct adsorption stages, thus achieving a maximum adsorption capacity of 3.752mmolg^-^1 of lead(II). Furthermore, it was found that the regeneration of titanate nanotubes loaded with the lead(II) ions can be readily achieved using the saturated EDTA disodium salt aqueous solution, thereby avoiding the trouble of disposal of adsorbent. The adsorption mechanism was also discussed in detail.

British Library Electronic Table of Contents (United Kingdom)

Abstract The term -stem cell- most commonly refers to embryonic stem cells, particularly in the lay media; however, it also describes other cell types. A stem cell represents a cell of multi-lineage potential with the ability for self-renewal. It is now clear that the plasticity and immortality of a given stem cell will depend on what type of stem cell it is, whether an embryonic stem cell, a fetal-placental stem cell or an adult stem cell. Stem cells offer great promise as cell-based therapies for the future. With evolving technology, much of the socio-political debate regarding stem cells can now be avoided.

Energy Technology Data Exchange (ETDEWEB)

The use of canisters filled with a charge of activated charcoal for field measurements of radon surface-emanation rates is well known. The performance of a canister, which is in current use by uranium mining companies and statutory authorities throughout Australia, was investigated using various charcoal thicknesses. To avoid the lower counting efficiencies associated with the smaller charges when measured at the exposed end, the canisters were counted from the closed end, which has become current practice for this canister.

Energy Technology Data Exchange (ETDEWEB)

Much as it is accepted for pollution control reasons air pollution abatement still is the subject of heated debates. Pollutant emissions can considerably be reduced with the help of electric power supplies. In order not to prejudice electric power users tariffs have to be adapted to the prices of other energy sources available on the market. There is a general need for energy conservation, resource conservation and the reduction of carbon dioxide emissions. Thermal insulation is among the remedial measures. Fundamental air pollution abatement measures will have to be avoiding smog warnings which are known to considerably interfere with both economic and private activities.

Energy Technology Data Exchange (ETDEWEB)

Taiwan`s LNG consumption is planned to rise more than threefold over the next four years as medium-term plans to develop power generation facilities increasingly rely on gas-fired combined-cycle stations to avoid the threat of power shortages. State-run Taiwan Power Company (Taipower) expects its LNG consumption to rise from 1.1 mn tonnes in 1996 to 3.4 mn tonnes in the year 2000. By then the first of several gas-fired private power stations is expected to enter service, further increasing Taiwan`s total LNG requirement for power generation. (Author)

Science.gov (United States)

Acute agitation is a frequent reason for emergency psychiatric intervention. It is important to intervene early to avoid escalation of agitation to aggression. Reducing risk by using effective treatments will result in fewer instances of seclusion and restraint, and fewer injuries to staff and patients. This paper will first review the epidemiology of aggressive behavior and mental disorders, followed by a discussion of assessment and diagnostic considerations. The pathophysiology of safety risk is discussed within the context of the model of the "triune brain." Pharmacological treatment strategies for acute episodes of agitated behavior will be discussed in detail. This includes newer formulations of novel antipsychotics such as liquids and rapidly disintegrating tablets, as well as intramuscular preparations. PMID:15335224

Energy Technology Data Exchange (ETDEWEB)

Knock limitations are investigated using natural gas, with diesel pilot ignition, as a fuel for the 3406 DI-TA Caterpillar diesel engine. Thermodynamic properties at TDC are generated by computer and compared with experimental results. Exhaust emissions are analyzed. A comparison is made of dual-fuel operation relative to diesel. Observations are made to determine the onset of knock. The onset of knock is characterized as a function of engine speed, load, inlet manifold temperature, and air-fuel ratio (A/F). The conditions at the inset of knock are determined using cylinder pressure data. The most efficient operating range is determined with knock avoidance as a prime parameter.

Energy Technology Data Exchange (ETDEWEB)

A thermal neutron imaging facility for real-time neutron radiography and computed tomography has been developed at the University of Texas reactor. The facility produced good-quality radiographs and two-dimensional tomograms. Further developments have been recently accomplished. A computer software has been developed to automate and expedite the data acquisition and reconstruction processes. Volume tomographic visualization using Interactive Data Language (IDL) software has been demonstrated and will be further developed. Volume tomography provides the additional flexibility of producing slices of the object using software and thus avoids redoing the measurements.

Energy Technology Data Exchange (ETDEWEB)

This book presents in simple terms the basis of molecular genetics and how it is used to obtain an understanding of the human genome. The author's central focus is the transistion of genetics from statistics to experimental manipulations, and he offers analogies that help readers visualize the genome, thereby avoiding conventional scientific presentations. He illustrates how genetics is used in scientific laboratories, in courtrooms, and in hospitals. Little is presented about the complex social and ethical issues raised by the Human Genome project.

Energy Technology Data Exchange (ETDEWEB)

Microcomputers are beginning to be used for energy analysis in many developing countries, and have the potential for making a significant contribution to the resolution of difficult analytical and data problems, and to improving communications between analyst and decision maker. Successful introduction of a microcomputer based on analytical capability, however, requires attention to several important factors in order to avoid the mistakes of the earlier mainframe computer era. This paper reviews the key issues of matching models to staff capabilities, of training, and of the operating environment, based on the author's first-hand experience with microcomputer projects in Uruguay, Haiti and Sri Lanka. 3 figures, 3 tables.

International Nuclear Information System (INIS)

In a program to develop a metastable beta alloy with improved fracture toughness, it was found that the tensile ductility of the alloy Ti-8 Mo-4.5 Cr-2.5 Al was strongly dependent on both processing history and annealing temperature. Evaluation of the microfracture mode of tensile samples by scanning electron microscope and metallographic techniques showed that the presence of a continuous grain boundary alpha is the most significant parameter controlling the ductility and is highly detrimental. It is concluded that, for optimum processing, the material must be worked prior to aging to avoid this grain boundary phase.

Energy Technology Data Exchange (ETDEWEB)

Delayed cerebral necroses after irradiation are to be divided into hemispheric and midline lesions, as they differ from each other in several aspects. Apart from the symptoms, they are differing in the duration of latency, in the course and prognosis, and also with regard to morphology. Though there is no doubt that radiation tolerance of cerebral midline structures is relatively limited, on biological grounds, evidence of a difference between the tolerated doses could not be given from the existent inhomogeneous radiation data, with the help of the NSD-concept. Radiation planning for the region of the head, nevertheless, carefully should avoid in every case to involve the structures of the cerebral midline.

International Nuclear Information System (INIS)

Three cases of primitive suprasellar germinomas are reported: the tumors show typical clinical signs (diabetes insipidus, disfunctions), but CT findings are not so specific. It is very important to reach a correct diagnosis based on clinical and radiological findings, because of very high radiosensibility of the tumor. The accuracy of preoparative diagnosis has been enhanced by CT in addition to conventional neuroradiological examinations. Due to the possible risk of meningeal spreading following biopsy, some authors prefer to avoid biopsy and to treat directly the patient by radiotherapy; a rapid reduction of the tumor size at the dose of 30 Gy suggest a possible germinoma.

International Nuclear Information System (INIS)

Hardened CMOS/SOI 29101 microprocessor, elementary cells and transistor shave been irradiated at levels between 10 Mrad(SiO_2) and 1 Grad(SiO_2) ("6"0Co and 10 keV x-rays). SIMOX buried oxide behavior in the range of 100 Mrad(SiO_2) and a channel-stopped MOS/SOI structure avoiding lateral leakage current are presented. These two items indicate the feasibility of a CMOS/SOI technology operating in the hundred Mrad(SiO_2) range.

International Nuclear Information System (INIS)

The manufacturing of TRIGA fuel rods with low enriched uranium follows in principle the same route as high-enriched uranium. The high purity of the primary metals (uranium, zirconium and erbium) is important for determining the equilibrium metal-hydrogen phases. The impurities from the metal, on the surface and from hydrogen may have an important influence on the hydriding process. This paper presents the aspects of the fuel contamination with oxygen during the manufacturing process of the low enriched uranium fuel. The continuous control of the oxygen concentration in the working zone ensures avoidance of the accidental contamination. Key words: manufacturing, fuel, oxygen, contamination. (authors)

British Library Electronic Table of Contents (United Kingdom)

The algorithmic, or consistent, tangent stiffness was introduced to improve the asymptotic convergence rate of the iterative correction algorithm for the evolutive analysis of elastoplastic structures. The original approach is based on a formulation of the elastoplastic law in terms of a plastic multiplier with an analysis which, in general, requires an operator inversion. A geometric description of the method, based on hypersurface theory, is proposed here to provide a clear picture of the algorithmic properties. An estimate of the tangent stiffness associated with finite step elastoplastic and elastoviscoplastic constitutive models is given. It is based on the properties of the projection operator on the elastic domain and avoids operator inversions retaining the beneficial properties of...

Energy Technology Data Exchange (ETDEWEB)

Emerging high-power microwave technologies require that bioeffects of exposure to this type of radiation be investigated for health and safety considerations. Disruption of animal behavior is reported to be a sensitive indicator of microwave exposure. Three behavioral tasks were chosen for this initial investigation of exposure to U.S. Air Force high-power microwave emitters. The tasks were: (1) single-trail avoidance, (2) water satiation, and (3) rotarod performance. Exposure to high-power microwave radiation from the USAFSAM peak-power simulator significantly affected the single-trail avoidance task. Neither the single-trail avoidance task nor rotarod performance was affected by the Gypsy emitter. However, animals exposed to 9-kW and 11-kW outputs from the USAFSAM emitter spent significantly less time imbibing water postexposure than sham-exposed animals. The most consistent finding in the animals exposed to the Gypsy ...

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Bose-Einstein condensation in nonlinear system

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The absence of high-temperature electronics is an obstacle to the development of untapped energy resources (deep oil, gas and geothermal). US natural gas consumption is projected to grow from 22 trillion cubic feet per year (tcf) in 1999 to 34 tcf in 2020. Cumulatively this is 607 tcf of consumption by 2020, while recoverable reserves using current technology are 177 tcf. A significant portion of this shortfall may be met by tapping deep gas reservoirs. Tapping these reservoirs represents a significant technical challenge. At these depths, temperatures and pressures are very high and may require penetrating very hard rock. Logistics of supporting 6.1 km (20,000 ft) drill strings and the drilling processes are complex and expensive. At these depths up to 50% of the total drilling cost may be in the last 10% of the well depth. Thus, as wells go deeper it is increasingly important that drillers are able to monitor conditions down-hole such as temperature, pressure, ...

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Full text of publication follows: Different to the very simple class of homogeneous non-equilibrium models (HEM) an one dimensional thermal-hydraulic theoretical drift-flux based and thus non-homogeneous coolant channel model and, as a result, an in itself complete thermal-hydraulic coolant channel module CCM have been established allowing to simulate in a very general way the steady state and transient behaviour of the most important parameters of a single- or two-phase fluid flowing within any type of heated or non-heated coolant channel (with an eventually varying cross flow area). To avoid mathematical discontinuities at the transition from single- to two-phase flow the coolant channel will, in its general form, be split into different regions, i.e. be looked as a basic channel (BC) which can consist of a number of different flow regimes and can, accordingly, be subdivided into a number of sub-channels (SC-s). All of them belong, obviously, to only two types of ...

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Most waste water treatment plants have processes to remove nutrients in order to avoid eutrophication in water receiving bodies. Regarding phosphorus removal. the most common option is chemical precipitation with ferric or aluminical precipitation with ferric or aluminium salts. We show here the successful experience carried out by the WWTP of Blanes and the company Safloc. A method ato remove phosphorus from waste water was developed by adding sodium aluminate. The use of this compound has turned out to be a sustainable way for this purpose in terms of costs, reliability and minimization of sludge production. (Author)

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We present results from a kinetic Monte Carlo simulation of boron transient enhanced diffusion (TED) in silicon. Our approach avoids the use of phenomenological fits to experimental data by using a complete and self-consistent set of values for defect and dopant energetics derived mostly from {ital ab initio} calculations. The results predict that, during annealing of 40 keV B-implanted Si at 800{degree}C, there exists a time window during which all the implanted boron atoms are substitutional. At earlier or later times, the interactions between free silicon self-interstitials and boron atoms drive the growth of boron clusters and result in an inactive boron fraction. The results show that the majority of boron TED takes place during the growth period of interstitial clusters and not during their dissolution. {copyright} {ital 1998 American Institute of Physics.}

British Library Electronic Table of Contents (United Kingdom)

Abstract An increase in chronic disease prevalence is contributing to health care cost growth and decreased quality of life in industrialized nations worldwide. Inadequate management of chronic diseases is a leading cause of hospitalizations and, thus, avoidable expenditures. In this study, we evaluated the impact of nurse-delivered care calls, the primary intervention of a proactive chronic care management (CCM) program, in a population aged 65 and older in Germany. In this analysis, hospital admission rates were evaluated among program enrollees who were diagnosed with diabetes, heart failure, coronary heart disease, or chronic obstructive pulmonary disease. The Intervention group comprised those members who participated in care calls (n?=?13,486), whereas the Comparison group included e...

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Slow, unexpected displacements have been experienced in most pressurized water reactor (PWR) surge lines. Sometimes, these displacement lead to gap closure at the pipe whip restraints. These movements occur because of thermal stratification. This movement has the potential to increase stresses to valves, which may exceed the material yield stress. To understand this phenomenon, Framatome, Commissariat a l'Energie Atomique, and Electricite de France have undertaken large programs for the study of (1) thermal-hydraulic tests with a half-scale Plexiglas surge line, (2) thermal-hydraulic computations of permanent states and transients with a two-dimensional model, and (3) mechanical analysis of displacements and computation of fatigue damage due to stratification. This paper deals with the last subject. Avoiding stratification in piping by process modifications is difficult because of the high flow rate needed. Alternative solutions for coping with ...

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Slurry characteristics have a significant impact on centrifugal pump performance. For instance, as particle size increases or the percent solids concentration increases, pump head and efficiency decrease. Therefore, before a slurry pump is selected, it is important to define the slurry characteristics as accurately as possible. The effect of the slurry characteristics on the head and efficiency of the centrifugal pump will be emphasized (the effect on flowrate is less significant). The effect of slurry characteristics is more predominant in smaller pumps (with smaller diameter impellers) than in larger pumps. The data and relationship between the various slurry parameters have been developed from correlations and nomographs published by pump vendors from their field data and test results. The information helps to avoid specifying an undersized pump/motor assembly for slurry service.

British Library Electronic Table of Contents (United Kingdom)

The common military explosives 2-methyl-1,3,5-trinitrobenzene (TNT), 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX) are distributed in many military training areas, and are thus encountered by grazing animals. The aim of this study was to examine small ruminant's intake of forage contaminated with explosives. An indoor, experimental setup was used to determine if contamination of forage by these compounds affected intake by sheep. The results clearly demonstrate that contamination by any of the three explosives reduced forage intake in sheep; in order of increasing avoidance: RDX

CERN Document Server

In the beam pipe of the positron damping ring of the Next Linear Collider, electrons will be created by beam interaction with the surrounding vacuum chamber wall and give rise to an electron cloud. Several solutions are possible for avoiding the electron cloud, without changing the bunch structure or the diameter of the vacuum chamber. Some of the currently available solutions for preventing this spurious electron load include reducing residual gas ionization by the beam, minimizing beam photon-induced electron production, and lowering the secondary electron yield (SEY) of the chamber wall. We will report on recent SEY measurements performed at SLAC on TiN coatings and TiZrV non-evaporable getter thin films.

CERN Document Server

The ALICE experimental area management team faces various challenges when it comes to sharing scarce resources, indispensable to any efficient installation in a category one worksite. Space, cranes, jigs, and personnel with key competences have to be carefully allocated to activities so as to avoid slowing down work progress. To this intent, a resource loaded planning has been developed that allows highlighting coactivities and prioritizing critical tasks. It uses the built-in capabilities of Microsoft Project. The use of this scheduling tool leads to a more efficient use of time and a safer work environment. The installation sequence resulting from this schedule is presented in this paper. The first part of the sequence focuses on the revision of the coils in the SX2 building. The dipole has then to be installed in the RB26 side of the UX25 cavern. This complex and resource intensive activity has to be performed in parallel with the services installation inside ...

International Nuclear Information System (INIS)

In this paper, research on pass schedule of tandem cold mill (TCM) is carried out. According to load (reduction, rolling force, motor power) balance, non-linear equations set with variables of inter-stand thickness is constructed. The pass schedule optimization is carried out by solving the non-linear equations set. As the traditional method, the Newton-Raphson method is used for solving the non-linear equations set. In this paper a new simple method is brought up. On basis of the monotone relations between thickness and load, the inter-stands thickness is adjusted dynamically. The solution of non-linear equations set can be converged by iterative calculation. This method can avoid the derivative calculation used by traditional method. So, this method is simple and calculation speed is high. It is suitable for on-line control. (author)

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In the course of designing a catalytic porous membrane reactor for experimental studies, both inside and outside of the non-reaction zones as well as the two ends of the membrane need to be completely sealed to ensure that there is no flow across the membrane in the non-reaction zone. Experiments show that up to 50% of the total flow across the membrane may be contributed by the axial flow along the wall of the non-reaction zones if only one side of the membrane is sealed. Another problem that cannot be solved by sealing is the capillary flow of the catalyst along the tube wall into the non-reaction zones when the catalyst is doped on the membrane. One of the best ways to avoid this axial flow of catalyst would be to use non-porous tubes in the non-reaction zones and join them with the porous membrane tube. In doing so, the cost of the membrane reactor could be reduced simply because shorter membrane tube is needed.

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We continue the study of the hole coupling resonator for free electron laser (FEL) application. The previous resonator code is further developed to include the effects of the azimutally asymmetric modes and the FEL gain. The implication of the additional higher order modes is that there are more degeneracies to be avoided in tuning the FEL wavelengths. The FEL interaction is modeled by constructing a transfer map in the small signal regime and incorporating it into the resonator code. The FEL gain is found to be very effective in selecting a dominant mode from the azimuthally symmetric class of modes. Schemes for broad wavelength tuning based on passive mode control via adjustable apertures are discussed. 12 refs., 7 figs., 1 tab.

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We apply a notion of static renormalization to the preparation of cluster states for quantum computing, exploiting ideas from percolation theory. Such a strategy yields a novel way to cope with the randomness of non-deterministic quantum gates. This is most relevant in the context of linear optical architectures, where probabilistic gates are inevitable. We demonstrate how to efficiently construct cluster states without the need for rerouting, thereby avoiding a massive amount of feed-forward and conditional dynamics, and furthermore show that except for a single layer of fusion measurements during the preparation, all further measurements can be shifted to the final adapted single qubit measurements. Remarkably, the cluster state preparation is achieved using essentially the same scaling in resources as if deterministic gates were available. Further, techniques to reduce the size of the required resource states will be presented.

International Nuclear Information System (INIS)

The dynamical decoupling (DD) aims at suppressing the decoherence by means of coherent control pulses. Even if devices exist where instantaneous pulses are an adequate approximation, experimentally a finite duration #tau#_p and a bounded amplitude are inevitable. They are the cause of additional errors which can be corrected by designing the pulse shape appropriately. The new pulse has the overall effect of an ideal, instantaneous pulse with the advantage of decoupling the spin (or qubit) from the bath up to the order O(#tau#_p"3). The limitation of the no-go theorem for #pi# pulses is avoided. Hence, the Uhrig sequence (UDD), originally thought for ideal #pi# pulses, works also for bounded control Hamiltonians. Numerical simulations show that concatenated sequences of real pulses are effective against general decoherence.

CERN Document Server

We complete the effective potential calculation of the two-loop, top/bottom Yukawa corrections to the Higgs boson masses in the Minimal Supersymmetric Standard Model, by computing the O(at^2 + at*ab + ab^2) contributions for arbitrary values of the bottom Yukawa coupling. We also compute the corrections to the minimization conditions of the effective potential at the same perturbative order. Our results extend the existing O(at^2) calculation, and are relevant in regions of the parameter space corresponding to tan(beta) >> 1. We extend to the Yukawa corrections a convenient renormalization scheme, previously proposed for the O(ab*as) corrections, that avoids unphysically large threshold effects associated with the bottom mass and absorbs the bulk of the corrections into the one-loop expression. For large values of tan(beta), the new contributions can account for a variation of several GeV in the lightest Higgs boson mass.

International Nuclear Information System (INIS)

Both the price of nickel and the allergic reaction that it can cause to human beings make it desirable to develop and use nickel-free austenitic stainless steels. The steels should be austenitic so as to avoid ferro-magnetism, a condition which has to be fulfilled for a number of requirements, including its use as implants in the human body, for wrist watch cases and many others. The paper presents the development of a nickel-free steel containing 11 percent manganese, 17 percent chromium, 4 percent molybdenum, and 0.9 percent nitrogen. This austenitic stainless steel has exceptional strength and corrosion resistance. These properties could result in numerous applications of the steel. A limitation, however, is that the steel is not weldable.

International Nuclear Information System (INIS)

With the assistance of mechanical activation, yttrium-stabilized #alpha#-SiAlON was prepared by combustion synthesis in air, instead of high-pressure N_2 atmosphere for the first time. The reaction activity of metallic particles was remarkably enhanced by mechanical activation, which conduced the reduction of grain size, increased the total surface area and formation of fresh surface. The formation of #alpha#-SiAlON by combustion synthesis in air was explained by a kinetically induced reaction mechanism, in which both initial formation of #alpha#-SiAlON and following avoidance of oxidation were fulfilled by the retardation of O_2 infiltration owing to the short reaction period and fast cooling rate.

British Library Electronic Table of Contents (United Kingdom)

In mobile animals, movement behavior can maximize fitness by optimizing access to critical resources and minimizing risk of predation. We sought to evaluate several hypotheses regarding the effects of landscape structure on American marten foraging path selection in a landscape experiencing forest perforation by patchcut logging. We hypothesized that in the uncut pre-treatment landscape marten would choose foraging paths to maximize access to cover types that support the highest density of prey. In contrast, in the post-treatment landscapes we hypothesized marten would choose paths primarily to avoid crossing openings, and that this would limit their ability to optimally select paths to maximize foraging success. Our limiting factor analysis shows that different resistant models may be sup...

British Library Electronic Table of Contents (United Kingdom)

Non-isothermal TG/DTG measurements are widely used to determine kinetic parameters of oxidation and gasification of carbons, e.g. by multi-heating rate methods. Thereby it is important to avoid spurious effects due to diffusion limitations. In this work, TG/DTG experiments with activated carbon were conducted under isothermal and non-isothermal conditions. The agreement of the experimental results with results of simulations based on the intrinsic kinetics, pore diffusion and external diffusion in/to the sample (crucible) is very good. The simulations show that mass transfer has an unwanted influence on TG measurements, if the concentration of the gaseous reactant (O2 and CO2) is too low and/or the heating rate is too high. Based on literature data, the simulation was extended to blast fur...

Energy Technology Data Exchange (ETDEWEB)

The development of 'Green Chemistry' requires new materials to replace the conventional organic chemistry by biological catalysts, to produce fine chemicals in an environmentally friendly manner. Microbial whole cells can be directly used as biocatalysts, providing a simple and cheap methodology since enzyme isolation and purification are avoided. High-density polyethylene (HDPE) is a very stable polymer though it can be activated by gamma radiation to induce grafting. Glycidyl methacrylate was grafted onto macroporous HDPE and PP in the range of 1-6%, proportional to the initial monomer concentration. Grafted polymers were further chemically modified with ethylenediamine to generate a cationic hydrogel of micron-size thickness onto the internal polymer surfaces. Modified polymers were able to immobilize Gram-positive and Gram-negative bacteria that can catalyze a chemical reaction as efficient as free cells do.

British Library Electronic Table of Contents (United Kingdom)

The shift to renewable energy options and low-carbon technologies, in response to the concerns over energy security and climate change, is proceeding more slowly than many would like. The usual argument against rapid deployment of new technologies is the costs imposed on the economy, commonly interpreted in terms of upfront costs to be borne or involving large cash transfers to fund, for example, efforts to preserve rainforests. In this contribution I argue that such a perspective provides a continuing barrier to taking effective action, whereas a perspective based on creation and use of carbon credits provides a means of avoiding the shock of abrupt industrial change. Carbon credits granted for bona fide carbon load reductions could be created through private initiative, for example by me...

British Library Electronic Table of Contents (United Kingdom)

Abstract: It seems that if abortion is permissible, then stem cell research must be as well: it involves the death of a less significant thing (an embryo rather than a fetus) for a greater good (lives saved rather than nine months of physical imposition avoided). However, I argue in this essay that this natural thought is mistaken. In particular, on the assumption that embryos and fetuses have the full moral status of persons, abortion is permissible but one form of stem cell research is not-the practice of creating embryos and then destroying them to extract cell material. Furthermore, I argue that the same is true on the assumption that embryos and fetuses have at least some moral status. I conclude that this form of stem cell research is permissible only if the embryos in question lack ...

British Library Electronic Table of Contents (United Kingdom)

Flame retardant recycled PET blends containing PC and triphenyl phosphite (TPP) have been designed using the following sequential processing strategy: PET and PC are first melt blended with a transesterification catalyst, allowing the compatibilisation of the blend, before adding TPP. The presence of this last component was shown to stop the transesterification reaction between PET and PC, avoiding chain breaking. In addition, TPP acts as a chain extender of PET, allowing the average chain length to be increased. The optimized blends obtained present "V-0" UL94 rating due to a better thermal stability leading to low flammability and to the development of an important, stable and covering char layer, resulting in self-extinguishability and very low Heat Release Rates during combustion.

Energy Technology Data Exchange (ETDEWEB)

Many oil-insulated electric power cables are limited by heat buildup caused in part by the low thermal conductivity of the oil. Circulation of the oil is known to reduce the cable temperature, but can lead to excessive pressure buildup on long cables when using conventional pumping methods. An alternate pumping method using distributed electric fields to avoid this pressure buildup is described. Electrohydrodynamic (EHD) pumping was studied both theoretically and experimentally for possible application in underground cable cooling. Theoretical studies included both analytical and finite-element analysis of the flow patterns driven by travelling electric fields. Experimentally, flow rates in a cable-pipe model were measured under a wide variety of operating conditions. Theory and experiment are in agreement for velocities below 10 cm/s, but higher velocities could not be reached in the experiment, due to increased electroconvection and, possibly, turbulence.

International Nuclear Information System (INIS)

The potential material class for use at 600"0C and more, e.g. for steam turbines with improved thermal efficiency, are austenitic steels. Using these steels with welded joints, it is to be considered that, by superposition of weld residual stresses and service stresses, extensive creep strains - and in the worst case crack formation - can occur locally. To assess the influence of these effects on service behaviour, different material states of CrNi-steels and Incoloy 800 were investigated with respect to strength, ductility and, especially, to crack and creep crack growth in the temperature range around 600"0C. It is shown that creep embrittlement, not microstructural changes as effected by weld heat input, causes heat affected zone (HAZ)-reheat cracking. Creep embrittlement can be avoided by special design and fabrication rules. (orig.).

British Library Electronic Table of Contents (United Kingdom)

The detection and characterization of deeply buried fatigue damage in thick, multi-layer airframe components pose significant technical challenges to the aviation safety community. Currently, no nondestructive evaluation technique is available to reliably detect such potential damage from the exterior of the airframe, which is highly desirable in light of inspection cost as well as avoidance of structure damage. Recent technological advances in high-sensitivity magnetic sensors, i.e., spin-dependent tunneling (SDT) sensors, make it feasible to employ electromagnetic inspection techniques for deep fatigue crack inspection. In this work, we report on the development and fabrication of a low frequency eddy current probe based on a magnetically shielded SDT pickup sensor concentrically located...

International Nuclear Information System (INIS)

Purpose: To flatten temperature distribution of coolant within a core. Constitution: The control device of the present invention is to vary reactivity of a fast breeder to control a reactor power. In general, the control device of this kind comprises a guide pipe arranged within the core and a control rod movable up and down within the guide pipe, and a coolant flows from bottom toward top within the guide pipe. Since a cooling flow rate has a margin, temperature of coolant outlet is extremely low as compared to a fuel assembly, and therefore temperature gradient in the vicinity of the top of the control rod becomes sharp to possibly impart thermal shock to the structural material. In the present invention, the flow passage of coolant is varied to thereby avoid outflow thereof into the core, thus flattening the temperature distribution of the coolant within the core. (Kamimura, M.).

International Nuclear Information System (INIS)

This report documents the research activities by Rogers and Associates Engineering Corporation on grant DE-FG03-93ER61600 during the funded project period from August 1993 to April 1996. The objective of this research was to characterize the mechanisms and rates of radon gas penetration of the different structural domains of the concrete components of residential floor slabs, walls, and associated joints and penetrations. The research was also to characterize the physical properties of the concretes in these domains to relate their radon resistance to their physical properties. These objectives support the broader goal of characterizing which, if any, concrete domains and associated properties constitute robust barriers to radon and which permit radon entry, either inherently or in ways that could be remediated or avoided.

Energy Technology Data Exchange (ETDEWEB)

An assessment is made of the biological effects and physical hazards of static and time-varying fields associated with the NMR devices that are being used for clinical imaging and in vivo spectroscopy. A summary is given of the current state of knowledge concerning the mechanisms of interaction and the bioeffects of these fields. Additional topics that are discussed include: (1) physical effects on pacemakers and metallic implants such as aneurysm clips, (2) human health studies related to the effects of exposure to nonionizing electromagnetic radiation, and (3) extant guidelines for limiting exposure of patients and medical personnel to the fields produced by NMR devices. On the basis of information available at the present time, it is concluded that the fields associated with the current generation of NMR devices do not pose a significant health risk in themselves. However, rigorous guidelines must be followed to avoid the physical interaction of these fields ...

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We discuss the renormalisation properties of the complete set of {delta}B=2 four-quark operators with the heavy quark treated in the static approximation. We elucidate the role of heavy quark symmetry and other symmetry transformations in constraining their mixing under renormalisation. By employing the Schroedinger functional, a set of non-perturbative renormalisation conditions can be defined in terms of suitable correlation functions. As a first step in a fully non-perturbative determination of the scale-dependent renormalisation factors, we evaluate these conditions in lattice perturbation theory at one loop. Thereby we verify the expected mixing patterns and determine the anomalous dimensions of the operators at NLO in the Schroedinger functional scheme. Finally, by employing twisted-mass QCD it is shown how finite subtractions arising from explicit chiral symmetry breaking can be avoided completely. (Orig.)

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The turbulent history of legislature concerned with the waste-management industry and the amount of material on this subject as well as the significance of the material in its own right led to the decision to publish all legal regulations on waste in one volume. It includes above all the Waste Law, Regulations on Determination of Waste, Regulations on Determination of Residual Products, Technical Instructions for Waste, Regulations for Monitoring Waste and Residual Products, Regulations on Probition from the Use of Chlorofluorohydrocarbons and Halon, Regulations on Packaging and Regulations on Sewage Sludge. The introduction explains the development and the role of the Waste Law and its applicability, goals and principles: The concept of waste, avoidance of waste, avoidance of waste tourism, the general welfare of the public; regulations on waste management, governmental means of monitoring waste management: Obligations to dispose of waste, ...

Energy Technology Data Exchange (ETDEWEB)

The most serious challenges in the design of chambers for inertial fusion energy (IFE) are 1) protecting the first wall from fusion energy pulses on the order of several hundred megajoules released in the form of x rays, target debris, and high energy neutrons, and 2) operating the chamber at a pulse repetition rate of 5-10 Hz (i.e., re-establishing, the wall protection and chamber conditions needed for beam propagation to the target between pulses). In meeting these challenges, designers have capitalized on the ability to separate the fusion burn physics from the geometry and environment of the fusion chamber. Most recent conceptual designs use gases or flowing liquids inside the chamber. Thin liquid layers of molten salt or metal and low pressure, high-Z gases can protect the first wall from x rays and target debris, while thick liquid layers have the added benefit of protecting structures from fusion neutrons thereby significantly reducing the radiation damage and activation. The ...

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