AIM: To evaluate the effects of percutaneous ozone injection via the posterior-lateral route and inner margin of the facetjoint in the treatment of large lumbar disc herniation.METHODS:...Full Text Available
Objective:To assess the efficacy of facetjoint infiltrations for pain relief in 44 selected patients with chronic nonradicular low back pain (LBP).Materials...Full Text Available
To evaluate injury patterns of facetjoints and associated soft tissue injuries in patients with acute traumatic cervical facetjoint injuries. From among patients with cervical spine trauma, 27 with facetjoint injuries, as seen on CT and MRI, were chosen for this study. CT scans were analyzed with regard to the location of facetjoint injury, the presence or absence of facet dislocation or fracture, and other associated fractures. MR images were analyzed with regard to ligament injury, intervertebral disc injury, intervertebral disc herniation, and spinal cord injury. The most common location of facetjoint injury was C6-7 level(n=10), followed by C5-6(n=8). Among these 27 patients with facetjoint injuries, 12(44%) ...
An assessment of the joint shear strength of exterior concrete beam-column joints reinforced internally with Glass Fibre Reinforced Polymer (GFRP) reinforcements under monotonically increasing load on beams keeping constant load on columns is carried out in this study. Totally eighteen numbers of specimens are cast and tested for different parametric conditions like beam longitudinal reinforcement ratio, concrete strength, column reinforcement ratio, joint aspect ratio and influence of the joint stirrups at the joint. Also finite element analysis is performed to simulate the behaviour of the beam-column joints under various parametric conditions. Based on this study, a modified design equation is proposed for assessing the joint shear strength of the GFRP reinforced beam-column specimens b...
Lumbar epidural anesthesia is useful in a variety of chronic benign pain syndromes, including lumbar radiculopathy, low back pain syndrome, spinal stenosis, and vertebral compression fractures. Given the increased number of epidural nerve blocks being performed, some have reported unexplained complications of a transient or permanent nature and with varying degrees of severity. However, no case has been reported of a broken epidural needle tip retained in the lumbar facetjoint area. This represents the first reported case presentation of foraminal stenosis developing in a patient after a retained epidural needle tip. PMID:21286465
The structure of a demountable vacuum joint designed for operation from -120 to +120 deg C is developed and tested. Requirements of especially low gas release from the materials used have been fulfilled; the same concerns low sealing efforts, repeated action and keeping tightness under loads, indium being used as a sealant. Experimental studies of demountable vacuum joints, dia 100,125,140,160,180 and 200 mm, with an indium sealant permit to make the following conclusions: 1. The joints are sealed at sealing specific efforts of 0.4 kg/mm (without considering atmospheric pressure). 2. The joints retain tightness at opening and closing a cover five times and under +-120 deg C. 3. To ensure repeated operation of the joint with continued stable sealing effort, one should make sure the sealed surfaces coincide at repeated sealing. 4. When operating demountable vaccum ...
This experimental study investigates the effectiveness of crossed inclined bars (X-bars) as joint shear reinforcement in exterior reinforced concrete beam-column connections under cyclic deformations. Test results of 20 joint subassemblages with various reinforcement ratios and arrangements including X-bars in the joint area are presented. The X-type, non-conventional reinforcement is examined as the only joint reinforcement and in combination with common stirrups or vertical bars. The experimental results reported herein include full loading cycle curves, energy dissipation values and a categorization of the observed damage modes. Based on the comparisons between the overall hysteretic responses of the tested specimens, it is deduced that joints with X-bars exhibited enhanced cyclic perfo...
Nano-wire arrays of Niobium were produced by small angle sputtering on facetted sapphire, using the self shadowing effect of the facets. A wire width of about 80 nm was adjusted, the mean (maximum) wire height was about 20 nm (30 nm), the length can be in the cm range. Meander-film morphologies of 20 nm mean (26 nm maximum) thickness were produced by conventional sputtering onto smooth sapphire substrates at elevated temperatures. The morphology of the wires was investigated with atomic force microscopy (AFM), using contact mode. Meander-films were studied by scanning tunnelling microscopy (STM). Hydrogen loading was performed by instantaneously increasing the hydrogen gas pressure above the solubility limit. Thus, an elongated hydride could be monitored in an about 30 nm thick wire. STM studies on meander-films show the presence of cylindrical hydrides. Local out-of-plane and in-plane expansion can be explained by the ...
Considering beryllium as plasma facing armour this paper presents recent results obtained in Russia. A special process of joining beryllium to a Cu-alloy material structure is described and recent results of thermal cycling tests of such joints are presented. Summarizing the results, the authors show that a Cu-alloy heat sink structure armoured with beryllium can survive high heat fluxes ({>=}10 MW/m{sup 2}) during 1000 heating/cooling cycles without serious damage to the armour material and its joint. The principal feasibility of thermal cycling of beryllium grades and their joints directly in the core of a nuclear reactor is demonstrated and the main results of this test are presented. The paper also describes the thermal cycling of different beryllium grades having cracks initiated by previously applied high heat loads simulating plasma disruptions. (orig.)
The paper discusses the aspects of repair and retrofitting technique adopted for a damaged reinforced concrete beam-column joint specimen under cyclic loading. A specimen designed based on Indian Standard specifications with consideration of seismic load but without adopting ductile detailing (NonDuctile) was investigated under reverse cyclic loading. Then, the damaged nonductile specimen was repaired with epoxy mortar and grouted using low viscous polymer, and retrofitted using fiber reinforced plastic (FRP) wrapping in beam and column components and steel plate jacketing in joint region. The experimental results showed that the retrofitted specimen not only regained its original strength and stiffness but also has overcome the deficiencies of nonductile detailing. The present study shows...
Some considerations regarding ice load in risk-based dam safety analysis are presented for small concrete dams. The most significant physical mechanisms leading to ice thrust on dams (such as thermal expansion and water level fluctuations) are outlined. Published literature on dam ice loads to examine ice load magnitude-return period relationships, sliding and overstressing failure mechanisms and structural performance criteria to resist ice loads, are also reviewed. Related loading combinations for structural safety evaluations were determined regarding the issue of simultaneity of ice loads with other events such as earthquakes. Parametric analyses were conducted on a small gravity dam section, 3m high, and a taller dam, 17.9 m high, to demonstrate the ultimate ice load carrying capability as a function of dam geometry and shear and ...
This study reports a determination of the polarity of WC facets in WC-Co alloys sintered at the liquid state. In these alloys, WC grains are delimited by basal facets and two sets of {101 0} prismatic facets, one set of facets being much more developed than the other. A variation of the shape is observed as a function of the composition of the alloy. High resolution transmission electron microscopy is used to investigate the polarity of the prismatic facets owing to the typical triangular patterns appearing on the images. The effect of the composition is investigated using two alloys with different carbon potentials and one containing VC and Cr3C2 as grain growth inhibitors. The interpretation of the images shows that in all cases, the same set of prismatic planes is favoured.
ObjectivesObjectives Not AvailableDescriptionThis proposal seeks to extend what is currently the most comprehensive offshore environmental data collection programme at a platform on the UKGS involving continuous collection of wave height and direction, wind speed and direction, current and wave particle kinematics. Data has been collected with this system since 1994 and the proposal is to extend this until 1999 thus providing an extensive set of storm data collected at 5Hz which will allow examination of the joint behaviour of wave, wind [continued...
Glass fiber-reinforced polymer (GFRP) reinforcing bars were used recently as main reinforcement for concrete structures. The noncorrodible GFRP material exhibits linear-elastic stress-strain characteristics up to failure with relatively low modulus of elasticity compared to steel. This raises concerns on GFRP performance in structures where energy dissipation, through plastic behavior, is required. The objective of this research project is to assess the seismic behavior of concrete beam-column joints reinforced with GFRP bars and stirrups. Two full-scale exterior T-shaped beam-column joint prototypes are constructed and tested under simulated seismic load conditions. One prototype is totally reinforced with GFRP bars and stirrups, while the other one is reinforced with steel. The experimen...
The VNC2 and VNC5 steel tests on endurance were carried out in order to determine the capacity for work of large welded samples and to investigate the methods of welding. The samples made by the arc welding demonstrated the most high endurance at low frequencies of loading during the test of welded joints made of the VNC2 steel. The application of the VNC2 steel interlayers together with intermediate heat treatment allows one to increase the static and fatigue strength of welded joints at corresponding decrease of the construction weight during welding of the VNC5 steel as well as its combination with the VNC2 steels. The gas protection deterioration during steel welding leads to considerable diversity of values of endurance.
An automatic loading roller for transmitting torque in traction drive devices in manipulator arm joints includes a two-part camming device having a first cam portion rotatable in place on a shaft by an input torque and a second cam portion coaxially rotatable and translatable having a rotating drive surface thereon for engaging the driven surface of an output roller with a resultant force proportional to the torque transmitted. Complementary helical grooves in the respective cam portions interconnected through ball bearings interacting with those grooves effect the rotation and translation of the second cam portion in response to rotation of the first. 14 figs.
This patent describes an automatic loading roller for transmitting torque in traction drive devices in manipulator arm joints includes a two-part camming device having a first cam portion rotatable in place on a shaft by an input torque and a second cam portion coaxially rotatable and translatable having a rotating drive surface thereon for engaging the driven surface of an output roller with a resultant force proportional to the torque transmitted. Complementary helical grooves on the respective cam portions interconnected through ball bearings interacting with those grooves effect the rotation and translation of the second cam portion in response to rotation of the first.
IntroductionMeniscal injury is a risk factor for the development and progression of knee osteoarthritis, yet little is known about risk factors for meniscal pathology. Jointloading...Full Text Available
To investigate the effect of external loads arising from differential thermal expansion between a substrate and a surface-mount component during thermomechanical cycling, specimens with a nickel surface-mount component on a copper substrate were prepared. Specimens consisted of two 100 #mu#m thick 1 mm"2 solder joints about 9 mm apart, with two designs. In one specimen (denoted 'dual-shear'), the as-fabricated joints were not stressed due to differential contraction during solidification and cool down. In the other specimen (denoted 'component'), a continuous copper substrate between the joints caused the nickel component to be put in compression during cool down, which imposed shear on the joints. To impose differential thermal shear strains, the 'dual-shear' specimen was clamped to a copper block to cause a significant reversal in sign of the shear imposed on the solder ...
Amotivation is a telling hallmark of negative symptomatology in schizophrenia, and it impacts nearly every facet of behavior, including inclination to attempt the difficult cognitive tasks involved...Full Text Available
For the purpose of digging up themes of the joint research which develop the R and D in the industrial technology field in Japan to a new stage, researchers were sent to the world representing research institutes to conduct the research survey of 'Nano-structured carbon and hydrogen absorption' and 'Development of the creation technology of nano-porous materials.' As to the former, an experiment on electrochemical hydrogen absorption of carbon materials including nanotubes was conducted by researchers dispatched, but the large absorption amount was not observed. As to the latter, visits were paid to Fraunhofer Institute and the related facilities in Germany, Princeton University, MIT, GIT and Naval Research Laboratories in the U.S., Orleans University in France, AO Research Institute (bone repair study) in Switzerland, Cambridge University and University of Bristol in the U.K., etc., and the research survey was made on the ...
We consider relay selection technique in a cooperative cellular network where user terminals act as mobile relays to help the communications between base station (BS) and mobile station (MS). A novel relay selection scheme, called Joint Uplink and Downlink Relay Selection (JUDRS), is proposed in this paper. Specifically, we generalize JUDRS in two key aspects: (i) relay is selected jointly for uplink and downlink, so that the relay selection overhead can be reduced, and (ii) we consider to minimize the weighted total energy consumption of MS, relay and BS by taking into account channel quality and traffic load condition of uplink and downlink. Information theoretic analysis of the diversity-multiplexing tradeoff demonstrates that the proposed scheme achieves full spatial diversity in the quantity of cooperating terminals in this network. And numerical results are provided to further confirm a significant energy efficiency ...
The behavior of MEMS devices is limited by the strength of critical features such as thin ligaments, oxide cuts joining layers, pin joints and hinges. Devices fabricated at Sandia's Microelectronic Development Laboratory have been successfully tested to investigate these features. A series of measurements were performed on samples with gage lengths of 15 to 1000 microns, using conventional and tungsten coated samples as well as samples that include the critical features of standard components in the test section. Specimens have a freely moving pin joint on one end that anchors the sample to the silicon die to allow rotation to reduce effects of bending. Each sample is loaded in uniaxial tension by pulling laterally with a flat tipped diamond in a computer-controlled Nanoindenter. Load is calculated by resolving the measured lateral and normal forces into the applied tensile force and frictional ...
For shut-down safety of the turbine generator (securing of auxiliary power operation after load shut-down and preventing the reaching of overspeed after load shut-down with disturbed turbine governing system) additional measures compared to those for superheated steam turbines are required for turbine generators in plants with pressurized water reactor (PWR) as well as those with boiling water reactor (BWR) . Equipment is described (e.g. overspeed govern or selecting connection, vacuum breaker, bypass valves, intercepting valves) which, depending on the own conditions of the individual turbine generator (e.g. run-up time, vacuum, enclosed energy), may be applied alone or in jointly. (orig.).
One of the main requirements to use Be as a candidate for plasma facing component in ITER is providing a reliable joint between Be and Cu-alloy heat sink structure. In this work authors present the results of recent activity on this way. To create Be/CuCrZr joints the unique fast e-beam brazing technology was developed in Russia. The numbers of Be/CuCrZr mock-ups were manufactured in Efremov Institute by fast e-beam brazing using Cu-Sn-In-Ni brazing alloy. These mock-ups were tested by Sandia Laboratory at the EBTS electron beam facility. The goals of the tests were to define the allowable dimensions of the armour tiles for the heat loads of more than 10 MW/m{sup 2}, to find the limit of bond strength for the Be/CuCrZr joint and response to heat loads and to estimate the life time of the brazed tiles by thermo-cyclic testing. The screening and thermal fatigue results are presented. ...
The power industry is moving toward the use of high-voltage transmission lines on tall, flexible towers. These towers are designed for heavier loadings than were previous towers, but the secondary effects of tower displacement tend to be ignored in the present day tower analysis. This paper examines the secondary effects from the large displacement of flexible towers, reviews the secondary stresses arising from joint rigidity and member continuity, and examines the reliability of tower strength predicted by the ASCE design guidelines. More realistic tower test acceptance criteria and a more reliable tower design methodology are suggested.
The susceptibility of CHN35VT-VD and 08CH18N10T stainless steels to stress corrosion cracking in water environment, simulating water solution found in threaded holes, was investigated using rising load line displacement tests of precracked C(T) specimens. To judge the role of oxidant on stress corrosion cracking of both stainless steels, the effect of dissolved oxygen content (fully deaerated water, water aerated at the beginning of the test) was studied. 7 refs.
The Wendelstein 7-X (W7-X) modular stellarator is under construction at the Max-Planck-Institut fuer Plasmaphysik in Greifswald, Germany. The W7-X magnet system contains 70 coils made up from helium cooled superconducting cables in aluminium alloy (EN AW-6063) jackets. Several hundred connections of the jacket to the cable joints are made by aluminium-to-aluminium welds. Due to geometrical and thermal boundary conditions these welds cannot be accomplished free from defects. Microscopic analyses of the welds show that a variety of small flaws such as cracks and pores develop during welding. The welds have thus to be dimensioned accordingly, and appropriate weld qualification, investigation and testing has to be done in order not to jeopardise the structural integrity and leak tightness. The weld is mechanically loaded during cool-down due to the difference in thermal contractions between the GRP insulation and the aluminium, and during operation ...
The Wendelstein 7-X (W7-X) modular stellarator is under construction at the Max-Planck-Institut fuer Plasmaphysik in Greifswald, Germany. The W7-X magnet system contains 70 coils made up from helium cooled superconducting cables in aluminium alloy (EN AW-6063) jackets. Several hundred connections of the jacket to the cable joints are made by aluminium-to-aluminium welds. Due to geometrical and thermal boundary conditions these welds cannot be accomplished free from defects. Microscopic analyses of the welds show that a variety of small flaws such as cracks and pores develop during welding. The welds have thus to be dimensioned accordingly, and appropriate weld qualification, investigation and testing has to be done in order not to jeopardise the structural integrity and leak tightness. The weld is mechanically loaded during cool-down due to the difference in thermal contractions between the GRP insulation and the aluminium, and during operation ...
This paper presents a method for analyzing the seismic response of a flat bottomed cylindrical liquid storage tank to vertical earthquake excitation. Here, vertical earthquake acceleration is considered to correspond to an increase in the density of a stored liquid. Taking into account the vertical and horizontal earthquake loads, hydrostatic pressure, and considering restrictive moment and shear forces at shell-bottom welded joint, the author has calculated circumferential and longitudinal stresses. These are combined to more accurately approximate the stresses at the base shell course. The calculated result closely conforms to the actual damage, termed ''elephant's foot,'' observed in the fuel storage tanks damaged in the Tangshan earthquake. This result shows that the ''elephant's foot'' phenomenon is not caused by buckling of the tank shell due to ...
Restructured power markets require concepts not only for extending the lifetime of existing plants, but also concepts for reducing the life-cycle costs of existing older steam power plants in order to remain competitive with the most modern and advanced power generation technology such as combined cycle power plants. Out of the broad range of methods to extend service life and increase availability, and to increase power output and efficiency, this paper focuses on full repowering. Full repowering replaces the old fired boiler with gas turbine(s) and heat-recovery steam generators (HRSG) as heat input to the existing bottoming cycle and reuses the steam turbine (ST) condenser and further balance of plant (BOP) equipment. The potential offered by this concept is demonstrated. Repowering and modernization projects are executed if they result in economic benefits for the operator. Investment decisions need to be prepared based on an estimate or proof of an adequate return on investment ...
A patient is presented with a cervical spinal cord transection which occurred after a motor vehicle accident in which the air bag deployed and the seat belt was not in use. The patient had complete...Full Text Available
The ternary complex factor (TCF) Elk-1 is a transcription factor that regulates immediate early gene (IEG) expression via the serum response element (SRE) DNA consensus site. Elk-1 is associated with...Full Text Available
Social stress is prevalent in many facets of modern society. Epidemiological data suggest that stress is linked to the development of overweight, obesity and metabolic disease. Although there...Full Text Available
Decreasing the aperture of a solar central receiver operating at high temperatures contributes significantly to the increase of the efficiency of energy absorption. However, decreasing the aperture also decreases the collection efficiency. A simple solution is using a 3D-CPC as secondary element for augmenting the energy collection, while the aperture can remain relatively small. Nevertheless, the receiver aperture as well as the secondary concentrator are usually rather large. For practical considerations an approximate solution may be chosen at times, designing the concentrator by a series of truncated cones. However, in particular cases, the solution of truncated cones remains expensive and unpractical and therefore the authors designed a CPC approximated by a series of trapezoidal planar facets. Under technical restrictions, there is an optimum for choosing the partition of the pure-CPC in truncated pyramids and the paper presents the method for a good ...
This final report for the Swiss Federal Office of Energy (SFOE) presents the results of a project that involves the building of a joint biogas plant serving 60 farmers and industrial companies with an annual processing capacity of 45,000 tons. The plant is to produce biogas to be fed into the gas mains and will not only reduce nutrient loading in a region with an extensive livestock industry but also reduce carbon dioxide emissions by using the gas as a motor fuel. The importance of the project with respect to both the environment and energy policy-making is discussed and the costs involved are examined. Details are presented on the technology used and on the material flows involved. Figures are quoted on energy production. The various biogenic substrates used, such as food wastes, waste oils, cereal wastes and used mushroom substrates, are discussed, as is the use of the solid and liquid outputs of the digester in farming activities.
The possible corrosion damage is discussed of the CrNi and CrNiMo types steels used as structural materials in WWER type nuclear power plants. It includes point and slot corrosion, corrosion cracking and corrosion fatigue as well as corrosion denting. Also discussed are test procedures that simulate operating conditions and are used for assessing the properties of metallurgical products (sheets and tubes) used in nuclear power engineering. Briefly described is a system for testing the said products in an aqueous medium while keeping the test parameters in a narrow range for a long time. Under the defined temperature, pressure and corrosion medium composition, the test specimens in this system can mechanically be loaded, both statically and dynamically or a temperature gradient can be produced at the tube-tube plate joint. (Z.M.). 1 fig., 1 tab., 10 refs.
A review of tests on earthquake-resistant reinforced concrete structural walls is presented. Laboratory tests of isolated walls and construction joints are discussed. Where appropriate, design recommendations are given. The review indicates only few experimental data are available for short walls which are directly applicable to nuclear power plant design. In particular, tests of short rectangular walls subjected to load reversals are needed. Tests are also needed to determine the damping and frequency characteristics of cracked short walls. Analytical and experimental results should be correlated so that the hysteretic response observed in tests can be realistically related to the analytical response 'demand' of nuclear power plant structures. (Auth.).
ObjectivesFirst comprehensive evaluation of the mechanical properties of an epoxy adhesive in different environments using a nano-indenter. ~%~~%~Use AFM/SEM and finite element modelling to generate knowledge of the precise mechanism of indentation in the epoxy adhesive. ~%~~%~Develop an improved data reduction algorithm for generating meaningful mechanical property data from indentation tests for adhesive materials.~%~ ~%~Validate the nano-indentation method of generating mechanical property data against [continued...]DescriptionThis project aims to address the problem of insufficient data on adhesive materials for effective modelling of joint behaviour in different environments. The methodology to be used is based on depth sensing indentation tests at different loads and rates and in different environments. Post-indentation deformation and recovery will be monitored by AFM and SEM and the indentation ...
The following subjects were discussed at the conference: Stability of welded joints, creep stress in CrMo steels, life prediction, developments in modern power plant steels, testing, calculation of deformation, crack propagation and crack analysis under complex loads. [German] Die Autoren der Tagung referieren ueber folgende Themen: Stabilitaet von Schweissverbindungen, Kriechbeanspruchung von Chrom-Molybdaen Staehlen, Lebensdauervorhersage, Entwicklungen fuer die Anwendung in modernen Kraftwerken, Prueftechnik, Berechnung von Verformung, Rissentwicklung und -bewertung bei komplexer Beanspruchung. (uke)
... CJCSI 3141.01C, Responsibilities for the Management and ... of a multivolume set of CJCS unclassified and ... (1) CJCSM 3122.01A, Joint Operation ...
... directed the transformation of designated Service operational headquarters into effective and scalable Joint Task Force headquarters capable of ...
There are currently no accepted industry standards for the tensile strain limits of girth welds. This paper investigated the behavior of girth welds with buried defects subjected to high longitudinal strains caused by soil movement. A strain design methodology based on a crack driving method was used to examine the factors influencing stain limits along with a constraint-sensitive fracture mechanics approach. No strength undermatching was used in the welds, and the defect location had no influence on crack driving force. The weld joint was assumed to have uniform tensile properties. A 3D finite element (FE) model was used to simulate pipe behavior. Symmetric boundary conditions were imposed on the symmetry planes, and uniform remote axial displacement was applied as the primary loading. Automated data processing routines were developed to extract and analyze the data. The crack driving force was computed directly from a crack tip deformation ...
The morphological evolution of ripples formed on the surface of Cd2Nb2O7 pyrochlore single crystals by focused ion beam (FIB) bombardment was investigated using in situ electron microscopy. At high ion fluences and off-normal bombardment angles, faceted surface ripples with a terrace-like structure were observed. The ripple propagation direction was oriented along the projected ion beam direction at incident angles ranging from 35 to 65 following high-dose ion bombardment. One side of the terrace was found to be perpendicular to the incident ion beam direction, while the other side was parallel to the ion beam. The terrace propagation velocity and direction were determined and interpreted on the basis of this asymmetric structure. A model based on the propagation of a shock wave that effectively self-selects a stable slope, was developed in order to explain the observed faceted ripple formation.
A new series of anatase TiO2 hollow structures were prepared by a facile hydrothermal process. When the hydrothermal time was increased from 20min to 72h, the resulting TiO2 solid spheres gradually transformed into TiO2 hollow spheres with higher surface crystallinity and exposed {001} facets. The as-prepared TiO2-72h sample exhibited the highest activity comparing to other TiO2-based samples and commercial product Degussa P-25 towards the selective photocatalytic oxidation of toluene to benzaldehyde. Such great photocatalytic performance was mainly attributed to enhanced UV-adsorption and better charge separation efficiency due to higher surface crystallinity of TiO2-72h.
Transmission electron microscopy studies on solution-annealed Alloy 800 revealed small (100-200 nm), spherical-shaped titanium carbide (face centered cubic structure) and large (200 nm-5 #mu#m), faceted titanium nitride (hexagonal structure) particles randomly distributed in the austenite matrix. The volume fraction of former particles was found to be greater than that of the latter. Corrosion studies of the alloy in acidic, chlorides and acidic chloride environments at room temperature indicated that the passivity of Alloy 800 was adversely affected by the addition Cl"- ions. X-ray photoelectron spectroscopy revealed that the surface film formed on the alloy at the onset of passivity consisted of Cr"3"+ (as Cr_2O_3), without any Fe"3"+/Fe"2"+ or Ni"2"+. Scanning electron microscopy studies indicated initiation of pitting at large, faceted particles, not at small, spherical-shaped ones.
We report a solution-phase synthetic route to copper nanoparticles with controllable size and shape. The synthesis of the nanoparticles is achieved by the reduction of copper(II) salt in aqueous solution with hydrazine under air atmosphere in the presence of poly(acrylic acid) (PAA) as capping agent. The results suggest that the pH plays a key role for the formation of pure copper nanoparticles, whereas the concentration of PAA is important for controlling the size and geometric shape of the nanoparticles. The average size of the copper nanoparticles can be varied from 30 to 80 nm, depending on the concentration of PAA. With a moderate amount of PAA, faceted crystalline copper nanoparticles are obtained. The as-synthesized copper nanoparticles appear red in color and are stable for weeks, ...
BackgroundSensory information from mechanoreceptors in the skin, muscles, tendons, and joint structures plays an important role in joint stability. A joint injury can lead to disruption...Full Text Available
Hyaluronan (HA) is important for joint cavitation, lubrication, volume regulation and synovial fluid drainage but little is known about the regulation of joint HA synthesis/secretion in vivo....Full Text Available
This monograph explores an alternative way of providing a JSOTF headquarters to the Joint Force Commander. Beginning with a history of joint SOF doctrine, the monograph outlines the evolution of special operations command and control and the subsequent ne...
Special Operations Forces (SOF) within a Joint Task Force are controlled by a Joint Special Operations Task Force (JSOTF). Presently, JSOTF headquarters are formed around the core of the Theater Special Operations Command (TSOC), a service SOF headquarter...
Conceptual documents like Joint Vision 2010 (JV 2010), the Concept for Future Joint Operations (CFJO), and the Revolution in Military Affairs (RMA) postulate that advances in technology and information superiority will revolutionize the way military force...
The divertor 'Large Project' was conceived with the aim of demonstrating the feasibility of meeting the lifetime requirements by employing the candidate armor materials of beryllium, tungsten (W) and carbon-fiber-composite (CFC). At the start, there existed only limited experience with constructing water-cooled high heat flux armored components for tokamaks. To this was added the complication posed by the need to use a silver-free joining technique that avoids the transmutation of n-irradiated silver to cadmium. The research project involving the four Home Teams (HTs) has focused on the design, development, manufacture and testing of full-scale Plasma Facing Components (PFCs) suitable for ITER. The task addressed all the issues facing ITER divertor design, such as providing adequate armor erosion lifetime, meeting the required armor-heat sink joint lifetime and heat sink fatigue life, sustaining thermal-hydraulic and electromechanical loads, ...
A portable X-ray image system is described comprising: (a) a base assembly including panels and hinges joining the panels together along edges, and compression stops for biasing the hinges to compensate for the weight of payload when mounted on the base assembly, the compression stops being located for interaction with the hinges for biasing the panels to exhibit upward bowing when laid upon a flat surface prior to loading, and to provide resiliency for facilitating the base assembly assuming a substantially flat configuration when a predetermined payload is placed upon the base assembly; (b) an X-ray member; (c) apparatus for detachably mounting a table member to the base assembly to hold the table member at a location above the base; (d) an X-ray source; (e) means for sensing X-rays to form an image; (f) means for mounting the X-ray source and the X-ray sensing means on opposite sides relative to the table member and supported by the base assembly; (g) releasable ...
Certain innovative coke-oven repair techniques are reviewed that represent an engineered approach to a successful rehabilitation of all types of coke-oven batteries. These techniques have been developed during the last 10 years and experience gained on a number of repair projects has shown that these techniques operate as a cohesive and comprehensive method of end flue and through-wall repairs to gain additional years of operating life to coke-oven batteries. Extended operations approaching 10 to 15 additional years of service at lower costs than a pad-up rebuild and, while meeting the environmental emission regulations, are attainable using the techniques of: Proper tie-in joint preparation; Improved bricking up methodology; Preheating refractory during bricking up; Installation of spring-loaded bracing system; and installation of flexible coke-oven doors. Repair methods that do not incorporate the above techniques are subject to premature ...
The performance of more than 3,000 offshore platforms in the Gulf of Mexico was observed during the passage of Hurricane Andrew in August 1992. This event provided an opportunity to test the procedures used for platform analysis and design. A global bias was inferred for overall platform capacity and loads in the Andrew Joint Industry Project (JIP) Phase 1. It was predicted that the pile foundations of several platforms should have failed, but did not. These results indicated that the biases specific to foundation failure modes may be higher than those of jacket failure modes. The biases in predictions of foundation failure modes were therefore investigated further in this study. The work included capacity analysis and calibration of predictions with the observed behavior for 3 jacket platforms and 3 caissons using Bayesian updating. Bias factors for two foundation failure modes, lateral shear and overturning, were determined for each ...
The paper presents the procedure of an investigation of WWER-1000 primary circuit temperature-stress field by the use of thermohydraulic computation data for a pressurized thermal shock event ''Core overcooling''. The procedure is based on a model of the plane stress state with ideal contact between wall and medium for the calculation. The computation data are calculated on the base of WWER-1000 thermohydraulic model by the RELAP5/MOD3 codes. This model was developed jointly by the Bulgarian and BNL/USA staff to provide an analytical tool for performing safety analysis. As a result of calculations by codes the computation data for temperature field law (linear laws of a few distinguished parts) and pressure of coolant at points on inner surface of WWER-1000 primary circuit equipment are received. Such calculations can be used as a base for determination of all-important load-carrying sections of the primary circuit pipes and vessels, which need ...
Thermal fatigue is one of the key factors governing the lifetime of the divertor plate. Tungsten is a promising candidate to cover the surface of the divertor plate in the design of the international thermonuclear experimental reactor (ITER). The W/Cr-bronze divertor small scale mock-ups were manufactured by hot isostatic pressing (HIPing) technique. Thermal fatigue tests of W/Cr-bronze divertor mock-ups have been carried out by an electron beam facility. The mock-ups were tested under a cyclic surface heat flux of 9 MW m"-"2 for 1000 cycles. The electron beam was loaded on the mock-up surface for 20 s and unloaded for 20 s, alternately. The flow rate of water coolant was 0.1 L s"-"1. The 0.3 mm diameter NiCr-NiSi thermocouples were used to monitor the temperature distribution of the mock-up. It was found that the maximum temperature of the tungsten surface was about 400 degree sign C. The saturated temperature at the joint of tungsten and ...
Information superiority provides the Joint force a competitive ... Information Grid (GIG) as it matures and fills the needs of the Joint Task Force ... representatives from The Army Secretariat, Headquarters Department of Army ...
The effect of WC particle size with the addition of VC as a grain growth inhibitor was investigated during the liquid phase sintering of WC-Co system. With increasing WC particle size at the same VC content, the effect of grain growth inhibition was increased. Also, with increasing the VC content, the grain shape of WC was changed from the faceted shape to the distorted shape, and the step density of the WC grain was increased. (orig.)
A concentrator which contains mirrors installed on a carrier frame by means of hinges is described. In order to improve the performance of a concentrator it contains a mechanism for controlling radiation density in a form of a screw attached to the carrier frame. It also contains a circular sliding coupling on the frame which has an annular groove with levers placed in it. The mirrors are connected to the sleeve by means of the levers, and the hinges are made cylindrical and have axes that are perpendicular to the axes of the screw.
The design of a 345-kV prefabricated capacitive-graded joint for oil-filled cables and the manufacture and testing of prototype joints are described. Tests on prototype No. 4 demonstrated the adequacy of the printed circuit design. It was not possible to consistently obtain high-quality capacitive sheets and substantial effort is required to remedy this problem. Advantages of these prefabricated joints are summarized, and specific recommendations are made for further development of the concept.
The Joint Convention on the Safety of Spent Fuel management and on the Safety of Radioactive Waste Management is the first legal instrument to directly address the safety of spent fuel and radioactive waste management on a global scale. The Joint Convention entered into force in 2001. This paper describes its process and its main achievements to date. The perspectives to establish of a Global Waste Safety Regime based on the Joint Convention are also discussed. (authors)
This paper reports on a flexible dimensionaly flush joint for 500kV aluminum-sheathed oil-filled cables capable of being assembled, pulled an installed in a similar manner to cables at site which has been developed. This joint is intended for use at intermediate points on long bridges or tunnels where local assembly and installation of conventional joints would be difficult. In developing the joint various novel and original techniques have been employed, including the flexible flush jointing of segmental conductors, the flexible jointing of paper insulation by a combination of wrapping-back and stepping methods, plus on-site aluminum sheath corrugating and sealing methods.
A singular stress field can occur at the edge of the joint plane in a thermally or mechanically loaded material compound. This stress field was calculated analytically and was compared with the results from the finite element method. If one of the two partners consists of ceramic material, unstable crack spread starting from faults in this strongly stressed area can lead to failure. In linear elastic material, the behaviour of a crack is clearly described by the stress intensity factors. These can be calculated for a known stress distribution in the uncracked structure by the method of the weight function. The corresponding weight functions for surface cracks parallel to the boundary surface were determined with the aid of suitable reference load cases. The effect of the position of the crack in the compound and the elastic constants of the compound are discussed. For examples, the stress intensity factors for cracks in a ...
The effect of aging on the microstructure and tensile properties of a type 316LN stainless steel/Alloy 800 joint, welded with 16-8-2 stainless steel consumable, has been studied to characterize and evaluate the joint for long-term elevated temperature service. The joint was subjected to accelerated againg heat treatments at 873 K up to 5000 h to simulate long-term service exposures. Analysis of the results from this investigation shows that this joint has adequate stability of microstructure and tensile properties even after prolonged exposure at elevated temperatures. (orig.)
Nickel-based alloys are presently used as brazing filler metals for components which undergo mechanical stress in corrosive conditions, f. e. heat exchangers. When soldering chrome containing steel parts with nickel based brazing filler metals additionally containing boron and silicon a reaction of chrome and boron can occur. This evolution of chromium borides, depositing on grain boundaries, causes a lack of chrome in the steel part. A drop of the chrome content in the parts below 13 % leads to a loss of corrosion resistance. It is possible to change the microstructure of brazing joints by modification with chromium and molybdenum. Continuous brittle phases could be successfully avoided with this modification. Furthermore it could be shown that the choice of additives, the heating respectively cooling rate and the brazing temperature have important influence on the microstructure evolution and therefore on the mechanical and corrosive properties of ...
Molecular beam epitaxy (MBE) grown Ge nanodots are found to come in a clear trimodal island distribution of huts, pyramids, and domes when grown on (001)Si at 550 deg. C. The island types appear in this order as Ge coverage increases and for a certain coverage all three types are found to coexist at this growth temperature. Previously Ge nanodots have mostly been divided into huts and domes at growth temperatures below 600 deg. C, or pyramids and domes above 600 deg. C. The (105) faceted pyramidal and elongated huts and the multifaceted domes are well known, but a distinction has not previously been seen between huts and a separate size distribution of similarly (105)-faceted pyramidal nanodots twice the size of huts, at temperatures below 600 deg. C. The 20-25 nm wide huts also appear to be the smallest obtainable self-assembled Ge dots on (001)Si, in accordance with predictions based on Si_1_-_xGe_x nanodots on (001)Si. They are about a ...
The effect of interfacial structure on the mechanical properties of aluminum-ceramic composite materials fabricated by liquid phase sintering was studied. The composites were based on two matrix alloys (powder metallurgy alloys 201 and 601) reinforced with either Al{sub 2}O{sub 3} or SiC particulate. Characterization of the interfacial regions demonstrated that the SiC-matrix interfaces were faceted whereas the Al{sub 2}O{sub 3}-matrix interfaces had an incomplete layer of a silicon-rich amorphous phase. Preferential attack of the particles during sintering is believed to cause the crystallographic facets to form on SiC. Locally high silicon concentrations near Al{sub 2}O{sub 3} particles led to the formation of a glassy phase from the reduction of Al{sub 2}O{sub 3}. The difference in interfacial structure resulted in a higher particle-matrix bond strength and therefore improved composite mechanical properties in the SiC-reinforced materials ...
Transmission electron microscopy studies on solution-annealed Alloy 800 revealed small (100-200 nm), spherical-shaped titanium carbide (face centered cubic structure) and large (200 nm-5 {mu}m), faceted titanium nitride (hexagonal structure) particles randomly distributed in the austenite matrix. The volume fraction of former particles was found to be greater than that of the latter. Corrosion studies of the alloy in acidic, chlorides and acidic chloride environments at room temperature indicated that the passivity of Alloy 800 was adversely affected by the addition Cl{sup -} ions. X-ray photoelectron spectroscopy revealed that the surface film formed on the alloy at the onset of passivity consisted of Cr{sup 3+} (as Cr{sub 2}O{sub 3}), without any Fe{sup 3+}/Fe{sup 2+} or Ni{sup 2+}. Scanning electron microscopy studies indicated initiation of pitting at large, faceted particles, not at small, spherical-shaped ones.
In the present paper it is assumed that above a limiting value of fission fluency (burn-up) a more intensive process of irradiation introduced chemical interaction occurs. A significant part of fission gas product is thus expected to be chemically bounded in the matrix of UO_2 fuel. The fission gas atoms substituting, for example, uranium atoms in the crystallographic lattice can form weak facets. At a certain saturation condition, division of the grains can occur at the weak facets and the increase in fission-gas products release may be expected. The fact that the process of grain division for high burn-ups (70-80 MWd/kgU) forms an extremely fine structure up to the temperature as high as 1100 "oC and simultaneously the observed decreases in fission gas concentration in the fuel supports this concept. The analysis of fission gas concentration change due to the formation of nanostructures in UO_2 fuel at high burn-ups in terms of total surface ...
Objective: To determine the reproductibility of three-dimensional volume and thickness measurements of the knee joint cartilage with MRI in volunteers. Methods: The knees of 7 healthy individuals (ages 23 to 58 yrs.) were sagitally imaged with a resolution of 2x0.31x0.31 mm{sup 3}, using a fat-suppressed FLASH-3 D sequence. The knee was repositioned in between replicate acquisitions, 6 data sets being obtained in each case. After semiautomatic segmentation and three-dimensional reconstruction of the cartilage, the thickness was determined independent of the original section orientation. The coefficient of variation for repeated volume measurements and the deviations of the maximal cartilage thickness values were calculated subsequently. Results: The mean variation of the cartilage volumes of the replicate measurements was 1.4% ({+-}0.8%) in the patella, 1.7% ({+-}1.5%) in the femur, 3.0% ({+-}1.2%) in the medial tibial plateau and 3.5% ({+-}2.0%) in the lateral ...
An effective rehabilitation strategy is proposed to enhance the strength and stiffness of the beam-column joint in this study. An analytical model is proposed to predict the column shear of the joints strengthened with carbon fiber reinforced polymer (CFRP). Three full scale interior beam-column joints, including two specimens strengthened with CFRP and one prototype specimen, are tested in this study. The specimens are designed to represent the pre-seismic code design construction in which there is no transverse reinforcement. A new optical non-contact technique, digital image correlation (DIC), which can measure the full strain field of specimen, is used to measure and observe the full strain field of the joint. The experimental results show that the beam-column joints strengthened with ...
The critical part of the trimetallic transition joint (type 304 stainless steel/Alloy 800/2.25 Cr-1 Mo steel), the Alloy 800/2.25 Cr-1 Mo steel joint welded with Inconel 182, was subjected to thermal cycling between room temperature and 873 K. The thermal cycling test procedure used produces accelerated failures in transition joints similar to those observed in steam generators of operating power plants. On thermal cycling, precipitation at the weld/ferritic steel interface decreased on post-weld heat treatment. This precipitation increased with increased prior ageing and applied stress. The results of these tests indicated a considerable improvement in performance of the trimetallic transition joint compared to the direct (bimetallic) transition joint. (orig.).
The recent definition of a postulated thermal shock accident followed promptly by system repressurization, termed an overcooling or pressurized thermal shock accident, has set a large analysis and research effort into motion. The essential elements are concerned with defining the accident transients, evaluating the instrumentation and controls that cause the postulated accidents, and evaluating the metallurgical and structural mechanics aspects of the reactor vessel with respect to its failure potential. This paper poses the question faced by the Nuclear Regulatory Commission (NRC) for the vessel steel embrittlement, annealing, and surveillance dosimetry facets of this postulated accident and provides information on our plans for study of this problem as well as current status.
The overall purpose of this research was to evaluate the independent and interactive effects of elevated levels of CO{sub 2} and O{sub 3} on tree leaf litter quality and decomposition. This research was conducted at the Aspen FACE (Free Air CO{sub 2} Enrichment) facility near Rhinelander, Wisconsin. This research comprised one facet of a larger project assessing how CO{sub 2} and O{sub 3} pollutants will alter carbon sequestration and nutrient cycling in north temperate forest ecosystems.
This handbook covers the general area of lubrication and tribology in all its facets: friction, wear lubricants (liquid, solid, and gas), greases, lubrication principles, applications to various mechanisms, design principles of devices incorporating lubrication, maintenance, lubrication scheduling, and standardized tests; as well as environmental problems and conservation. The information contained in these two volumes will aid in achieving effective lubrication for control of friction and wear, and is another step to improve understanding of the complex factors involved in tribology. Both metric and English units are provided throughout both volumes.
...2010-07-01 false Loading and haulage equipment; inspection and maintenance... § 77.1606 Loading and haulage equipment; inspection and maintenance. (a) Mobile loading and haulage equipment shall be inspected by a...
...position to receive material. (2) Self-loading haulage equipment used as a loading machine. In working places in which self-loading haulage equipment is operated to load material, the areas which...
Objectives To test the hypotheses that, compared with conventional outpatient consultations, joint teleconsultation (virtual outreach) would incur no increased costs to the NHS, reduce...Full Text Available
The Joint Commission on Accreditation of Hospitals (JCAH) has continuously emphasized improvement in the quality of care provided in hospitals as the central purpose of the accreditation process. In...Full Text Available
Exact anatomic knowledge about the location of the gonads and the application of corresponding measures of radiation protection are the preconditions for an efficient reduction of the danger of a possible genetic damage as a result of radiation exposition during X-ray examination of the hip joint of newborns. (VJ).
The purpose of the Joint Task Force Headquarters Master Training Guide (JTF HQ MTG) is to provide a descriptive, performance-oriented training guide to assist leaders in training their units. It also serves as a guide for the JTF Headquarters in actual op...
We studied multi-joint coordination during tasks of transporting real and imaginary objects with two arms. One of the arms was unexpectedly arrested in one third of trials performed. In the...Full Text Available
Examination of a painful hip is fairly concise and reliable at detecting the presence of a hip joint problem. Hip joint disorders often go undetected, leading to the development of secondary disorders....Full Text Available
This joint statement was developed by the CMA and the Canadian Pharmaceutical Association, a national association of pharmacists, and includes the goal of drug therapy, strategies for collaboration...Full Text Available
...COMCAM forces document Air Force and air component activities...supported unified command or joint task force commander, through the...Force COMCAM forces in a joint environment. If an...share of Unified Command headquarters COMCAM and visual...
Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) are promoting the joint project integrating both the Neutron Science Project (NSP) of JAERI and the Japan Hadron Facility Project (JHF) of KEK for comprehensive studies on basic science and technology using high-intensity proton accelerator. This document describes the joint project prepared by the Joint Project Team of JAERI and KEK to construct accelerators and research facilities necessary both for the NSP and the JHF at the site of JAERI Tokai Establishment. It was originally written in English and translated into Japanese with some corrections. (author)
... The pharmacologist/toxicologist and the statistician will jointly determine if a statistical review is needed and when the review should be done. ...
... from theory to practice will be significantly reduced while intrinsically revolutionizing the approach to engineering network security architectures. ...
runs are necessary, provision shall be made for expansion joints, motion of the units, or similar compensation to ensure that no excessive strains are ...
... to integrate and synchronize SC efforts and capabilities, as noted in the SC Roadmap, the joint community needs to publish SC policy and expand ...
This conference provided a forum for more than 500 delegates from industry, government universities and research centres to share their professional knowledge on research and development that affects all sectors of geotechnical engineering, applied geology and hydrogeology. Accomplishments in the geoenvironmental field were also highlighted. The geotechnical sessions were entitled: pile foundations and load testing; excavations and special foundation issues; reinforced soil and soil-structure interactions; advances in modelling, constitutive issues; advances in modelling, consolidation and other applications; advances in modelling, discrete elements and slope stability; embankments and dams; landfills and barriers; fundamental soil mechanics; soil mechanics and ground movement; GIS and remote sensing; landslides and slopes; cone penetration tests and liquefaction assessment; rock mechanics; engineering geology; geoenvironmental sustainability; oilsand and petroleum ...
For large transmission steel towers to be built in a mountainous area, caisson type pile foundations are often applied. The works for construction of this kind of foundation are manned operations such as drilling, arranging reinforcements, concrete laying, etc. in a narrow vertical pit which is 3m in diameter and about 20m in depth, but securing labour force of good quality for such works becomes increasingly difficult. In order to cope with the above situation and achieve reduction of costs, shortening of construction period, improvement of safety, saving of manpower, etc. a power supply company and construction companies have developed jointly a method of unmanned construction in a caisson type pile foundation pit. This method consists of the use of a caisson type pile full size excavator (this consists of an excavator proper, a vacuum soil discharging device, a monitor/controller, a load crane and a reaction pad, and performs continuously ...
Authors obtained T1-weighted MRI images of the femoral head after fracture of the femoral neck and classified the signals into four patterns to investigate the sequential changes of the femoral head. The T1-weighted MRI images obtained initially after femoral neck fracture showed a normal pattern in 10 of the 15 hip joints studied. MRI images obtained subsequently still showed the normal signal pattern in eight of the 10 hip joints which had shown the normal pattern in the first MRI, while two of the 10 joints subsequently showed a band pattern. The joint with the homogeneous pattern in the first MRI subsequently showed a band pattern. Of the three joints with an inhomogeneous pattern in the first MRI, two joints showed a subsequent band pattern, and the other a normal pattern. The joints which showed a band pattern continued to show a ...
The objective of the project was to develop a welded tubular joint database to assess the fatigue design curves (X and X{prime}) in the American Petroleum Institute design code (API RP2A). Changes in the curve-fitting method and screening criteria (primarily the exclusion of the very thin tubular joints) produced results different from those reported previously. The current results show that the X and X{prime} curves are too conservative and that a new curve should be adopted. The Department of Energy T{prime} curve was found to be consistent with the screened tubular joint air data and is recommended for use in API RP2A. The weldment size effect exponent (n) of 0.25 in the current version of API RP2A was found to be too small, and a higher value of 0.30 consistent with the Department of Energy recommendations is recommended. The fatigue test results for tubular joints tested in air and tubular ...
As an engineered barrier system in the geological disposal of high-level waste, multibarrier system is considered. Multibarrier system consists of the vitrified waste, the overpack and the buffer. Bentonite is one of the potential material as the buffer because of its low water permeability, self-sealing properties, radionuclides adsorption and retardation properties, thermal conductivity, chemical buffering properties, overpack supporting properties, stress buffering properties, etc. As the construction technology of the buffer, the block installation method and in-situ compaction method, etc, are being investigated. The block installation method is to emplace the buffer blocks manufactured in advance at the ground facility, and construction processes of the block installation method at the underground will be simplified compared with the in-situ compaction method. However, the block joints of buffer might be a mechanical weak portion or might be a preferential ...
The purpose of this paper is to establish probabilistic models for still-water loads, based on design data, and the combined still-water and wave load effects for semi-probabilistic and probabilistic design of floating production, storage and offloading vessels (FPSO). A new still-water load model for FPSOs is proposed, based on a Poisson square-wave model, with a modified Weibull distribution for load intensity, which accounts for load control during operation. The long-term variation of wave-induced load effects is modelled by a Poisson square-wave process. A new solution for the combined effect is derived. A procedure for determining characteristic extreme values for individual and combined load effects, and load combination factors, is established. The methodology is used to illustrate...
Measurements of human joint motion frequently involve the use of opto-electronic and other motion analysis systems where some type of makers are used to establish joint motion within a global reference coordinate frame. Typically, this global reference coordinate frame is chosen to be most convenient for the person carrying out the experiment in which the joint motion is measured, and Euler angles are chosen as the measure of joint motion. Results, however, may be quite arbitrary and therefore rendered meaningless if the reference frame is not properly chosen with respect to the physical joint axis. In order to make a proper choice of coordinate axes in the reference frame, one must take into consideration both the location and the orientation of die physical joint axis relative to the reference frame`s axes. In nature, joint axes can exist ...
The main facets of professor N.I. Pirogov's professional activity are outlined. Forensic medicine (in the first place its organizational and practical aspects) was an integral component of his scientific and clinical work, along with applied anatomy and surgery. Landmark publications of N.I. Pirogov are listed with special reference to those concerned with forensic medical expertise of medical malpractice cases, postmortem inspection and intravital examination procedures, wound ballistics studies, the atlas of forensic pathology, etc. The surgeon and anatomist N.I. Pirogov can be justly regarded as a founder of forensic medicine in this country. PMID:21866839
The technical complexity of intraoperative radiotherapy (IORT) requires modification of the standard physical and dosimetric methods used in external electron beam therapy. At the National Cancer Institute, a number of technical innovations have been integrated into ongoing clinical studies of IORT. These include: (1) an electron beam applicator system that is significantly different from other IORT systems and includes customized squircle applicators; (2) peripheral dose shields; (3) a modified surgical table replacing the standard radiation treatment couch; and (4) routine use of multiple IORT fields that necessitates field matching. The IORT applicator system and related devices and techniques are dosimetrically characterized in detail both for use in the IORT program and in order to illustrate many useful facets of electron dosimetry.
In this paper we demonstrate the electrodeposition of nickel, a common ferromagnetic material, in various magnetically desirable shapes including nanowires, nanoparticles and highly faceted shells. In order to obtain three dimensional mesostructures, the electrochemical deposition of nickel was performed on highly oriented pyrolytic graphite (HOPG) under different electrolyte composition and deposition potential conditions. Under potentiostatic deposition at one distinct potential negative with respect to the reversible potential of nickel, three stages of nucleation and growth take place leading to a complex morphology of deposits. However, dual-pulse potential deposition and electrodeposition in low pH solutions causing hydrogen evolution, lead to nickel deposits in the form of nanowires...
The multi-faceted research effort of the EBIT (Electron Beam Ion Trap) program in N-Division of the Physics and Space Technology Department at Lawrence Livermore National Laboratory (LLNL) continues to contribute significant results to the physical sciences from studies with low energy very highly charged heavy ions. The EBIT program attracts a number of collaborators from the US and abroad for the different projects. The collaborations are partly carried out through participating graduate students demonstrating the excellent educational capabilities at the LLNL EBIT facilities. Moreover, participants from Historically Black Colleges and Universities are engaged in the EBIT project. This report describes EBIT work for 1995 in atomic structure measurements and radiative transition probabilities, spectral diagnostics for laboratory and astrophysical plasmas, ion/surface interaction studies, electron-ion interactions studies, retrap and ion collisions, and ...
Motion Camouflage (MC) is illuminated as a novel strategy in counterattacking anti-satellite by way of stealth trajectory scheduling. The dynamics model of MC in space is developed and a quadratic function with three boundary constraints is employed for trajectory determination. Based on the model a scenario is set to run the simulation. The results indicate given the designed acceleration input, the predator will be moved following a prescribed route, which precisely locates the predator between two objects at each time instant. In the last approaching phase, the motion is achieved with a big bumping rate which guarantees the power of this striking. Methods for deriving minimum fuel cost in the fixed approaching duration and the minimum approaching duration in limited acceleration input are proposed and are verified in the simulation. At last, camouflage is recognized as a multi-faceted affair, in which stealth trajectory design is considered an effective ...
Buried ridge stripe lasers have been grown on InP in two steps by gas source molecular beam epitaxy. The active structure consists of a compressively strained layer multi quantum well with an equivalent wavelength emission at 1.5 [mu]m. The stripe was defined by reactive ion etching. A threshold current of 22 mA was reproducibly obtained on a laser length of 500 [mu]m. A CW output power of 48 mW per facet was achieved. In addition, preliminary accelerated aging tests have shown the high reliability the structure. (orig.)
Most mechanical forces acting on the skeleton are generated either through impact with the ground (i.e., gravitational loading) or through muscle contractions (i.e., muscle loading). If one...Full Text Available
An estimator for the load share parameters in an equal load-share model is derived based on observing k-component parallel systems of identical components that have a continuous...Full Text Available
In this paper an attempt is made to forecast load using fuzzy neural network (FNN) for an integrated power system. Here, the proposed system uses a two stage FNN for a short term peak and average load forecasting (STPALF). The first stage FNN deals with the load forecasting and the second stage algorithm can be worked independently for network security. This technique is used to forecast load accurately on week days as well as holidays, weekends and some special occasions considering historical data of load and weather information and also take necessary control action for network security.
One of the most challenging problems in Opportunistic Spectrum Access (OSA) is to design channel sensing-based protocol in multi secondary users (SUs) network. Quality of Service (QoS) requirements for SUs have significant implications on this protocol design. In this paper, we propose a new method to find joint policies for SUs which not only guarantees QoS requirements but also maximizes network throughput. We use Decentralized Partially Observable Markov Decision Process (Dec-POMDP) to formulate interactions between SUs. Meanwhile, a tractable approach for Dec-POMDP is utilized to extract sub-optimum joint policies for large horizons. Among these policies, the joint policy which guarantees QoS requirements is selected as the joint sensing strategy for SUs. To show the efficiency of the proposed method, we consider two SUs trying to access two-channel primary users (PUs) network modeled by discrete ...
... Accession Number : ADD431225. Title : Influence of Fiber Loading on Thermal Ablation of PTFE,. Corporate Author : Personal Author(s) : Letson,KN. ...
This document is the annual update of the FFTF and Advanced Reactors Transition Program Resource Loaded Schedule for FY 2002 using current project direction and authorized funding levels
The mixed structure of a nuclear reactor building is composed of SC-columns, S-beams, S-joints and PCa-panels. Following the last report (Part 7)[1], the main test results of the mixed structure, that is, the deformation mode, strain distribution and shear strength, are described. The S-joints using ultrahigh strength materials had no buckling nor shear slipping. The proposed mixed structure resisted the external horizontal forces under integrated uniformity among SC-columns, S-joints and PCa-panels. It could be confirmed that the mixed structure can be established. (author)
Twenty-seven patients with symptoms or clinical findings suggesting joint or bone disorders of the anterior chest wall (ACW) were evaluated by spiral CT with 3-dimensional (3-D) and multiplanar reconstructions. Preceding conventional ACW tomography was performed in 10 patients. ACW joint and bone changes were visualized more adequately by coronal 2-D reconstructions based on spiral CT than by conventional tomography. In addition, nonossified costal cartilages and soft tissue lesions were demonstrated. 3-D reconstructions sometimes added information, especially in patients with fracture and dislocation. (orig.).
Studied are the mechanical properties of welded joints and heat affected zones of the Kh8N10T steel and OT4 and VT1-2 titanium alloys on welding in Ar+deltaF_6 and Ar+CCl_2F_2 mixtures contributed to a decrease of porosity. Tensile and impact tests of welded joints have revealed that additions of sulfur hexafluoride into argon causes a decrease of impact strength in titanium alloy when the tensile strength does not depend on the composition of a halogen-containing atmosphere. Freon (CCl_2F_2) additions decrease only slightly the impact strength of the investigated alloys.
Magnetic resonance (MR) imaging and histopathology were used to diagnose an articular process synovial myxoma in a dog. On MR images, the tumor was characterized by distortion of the left L1-L2 articular process, widening of the articular process joint, and the presence of a mass contiguous with the synovium of the articular process that displaced the spinal cord. The tumor was T2-hyperintense, T1-hypointense, relative to muscle, and had mild contrast enhancement. The MR features of articular process synovial myxoma may be distinct from other diseases of the articular process joint.
Subcommittee of the Joint Committee on Atomic Energy of the United States, Outer Space Propulsion by Nuclear Energy, hearings, 85th Cong., 2d sess., 22, ...
Microscopy and chemotaxonomy from HPLC analysis of phytoplankton pigments initiated in 2003 suggest that Noctiluca miliaris blooms are becoming more intense ...
... Headquarters Element, Defense Logistics Agency, Support Detachment 3 ... Joint Task Force, Team 6 ... 19th Special Forces Group, Support Element 1 ...
... 7th Joint Task Force Augmentation Team Schwetzingen ... Headquarters 85th Division Training Support, Detach 2 ... 20th Special Forces Company A ...
... WHS- Washington Headquarters Service. ... US Military (ie, Army, Navy, Air Force) service publications ... Strike Group to Fight in the Joint Task Force. ...
ObjectivesTo determine what biodiversity data is held by record centres for the South Downs Lifescapes pilot area and the format in which it is stored.
... WHS- Washington Headquarters Service. ... ie, Army, Navy, Air Force) service publications ... The Case of the Rapid Deployment Joint Task Force. ...
This paper summarizes the main features of four current REDD proposals: Compensated Reduction, Papua New Guinea et al; Joint Research Center; and Brazil. ... ...
of Earth Science data and information management capabilities. Dale Schulz/400 . For your exceptional achievement in leading the joint LaRC/GSFC team in ...
... WHS- Washington Headquarters Service ... but also with respect to other Joint, National and ... unit of action (UA) combat team or task force is organized ...
... Joint Meritorious Award to DLA," Dimnsions Vol. ... recently the Defense Finance Accounting Services (DFAS ... gmbAt Service SUoDort Field Manual. ...
... In this manner, a JBI-enabled COI would have the full suite of JBI information management capabilities, but would still be based on and have full ...
... Joint Staff and other US Military (ie, Army, Navy, Air ... The major products of this work are significant advances in ... Keywords: Dogs; Laboratory animals ...
OBJECTIVE: To evaluate the interobserver agreement of ultrasonographic assessment of finger and toe joints in patients with rheumatoid arthritis (RA) by 2 investigators with different medical backgrounds. METHODS: Ultrasonography and clinical examination were performed on 150 small joints of 30 patients with active RA. A General Electric LOGIQ 500 ultrasound unit with a 7-13-MHz linear array transducer was used. In each patient, 5 preselected small joints (second and third metacarpophalangeal, second proximal interphalangeal, first and second metatarsophalangeal) were examined independently on the same day by 2 ultrasound investigators (an experienced musculoskeletal radiologist and a rheumatologist with limited ultrasound training). Joint effusion, synovial thickening, bone erosions, and power Doppler signal were evaluated in accordance with an introduced 4-grade semiquantitative scoring system, on ...
... Experts ( Appendix 5 ), and the NMFS-Sea Grant Joint Graduate Fellowship Program ( Appendix 6) . The Task Force consisted of one representative from NMFS Headquarters and 1-2 rep...
Jan 14, 2004 ... presented to the nation at NASA Headquarters, Washington, D.C., ...... Board/Air Force Scientific Advisory Board Joint Task Force on ...
Feb 6, 2003 ... Director, Plans and Programs, Headquarters Air Force Materiel Command, .... Commander of the Joint Task Force Southwest Asia at Prince ...
... (l0)6o). 316. Statf,'ent. In Hearings before the Subcommittee on Research, Do'v,-Iopment, and Radiation of the Joint Committee on Atomic Energy. ...
...QUALIFICATION AND CERTIFICATION OF LOCOMOTIVE ENGINEERS Implementation of the Certification...operations and certifies locomotive engineers from a different railroad...designated supervisor of locomotive engineers or a certified train...
joint task force (JTF), division (OIV) and regimental combat team (RCT) with ..... Headquarters, Department of the Army. (HQOA), (2010). Field Manual 2-0 ...
This report describes the experimental researches on the polarization Characteristics of symmetric GaAs-GaAlAsP double heterojunction lasers, and analyses the mode-competition processes of these lasers. The experiments showed that semiconductor laser is emitted spontaneously and does not indicate optical polarization characteristic when it is biased under the threshold current. When it is biased above the threshold current, the laser for thin active layer of d = 0.15approx.0.40 ..mu..m is generally observed only in fundamental order mode, and TE mode polarization is predominant. At this time, polarization selection is dependent on Fabry-Perot cavity facet (cleaved face) mode reflectivity R/sub 0/. But TM mode is saturated at the threshold, the current applied to the laser above the threshold is used to enhance the TE polarization when the active thickness d is larger than 0.4 ..mu..m, the competition between TE and TM mode, fundamental order an higher order mode ...
This document describes a simple and general way to generate House Simulation Protocol (HSP)-consistent internal sensible and latent loads in unoccupied homes. It is newly updated based on recent experience, and provides instructions on how to calculate and set up the operational profiles in unoccupied homes. The document is split into two sections: how to calculate the internal load magnitude and schedule, and then what tools and methods should be used to generate those internal loads to achieve research goals.
This is a patent for a device to increase compaction of the loaded batch in a coking chamber that assures a balanced compaction of the batch from the upper to the bottom layer. The leveling rod has a device on the external end that causes the rod to shift vertically and bring pressure on the material and the pressing attachment. Opposite the loading hoppers of the coking chambers there are guides that ensure the rod will be sunk perpendicularly into the loaded material.
A new test methodology is described which allows access to loading rates that lie between split Hopkinson bar and shock-loading techniques. Gas gun experiments combined with velocity interferometry techniques have been used to experimentally determine the intermediate strain-rate loading behavior of Coors AD995 alumina and Cercom silicon-carbide rods. Graded-density materials have been used as impactors; thereby eliminating the tension states generated by the radial stress components during the loading phase. Results of these experiments demonstrate that the time-dependent stress pulse generated during impact allows an efficient transition from the initial uniaxial strain loading to a uniaxial stress state as the stress pulse propagates through the rod. This allows access to intermediate loading rates over 5 x 10{sup 3}/s to a few times 10{sup 4}/s.
The present invention concerns a high thermal load heat receiving plate such as a divertor plate of a thermonuclear device. The high thermal load heat receiving plate of the present invention has a cooling performance capable of suppressing the temperature of an armour tile to less than a threshold value of the material against high thermal loads applied from plasmas. Spiral polygonal pipes are inserted in cooling pipes at a portion receiving high thermal loads in the high temperature load heat receiving plate of the present invention. Both ends of the polygonal pipes are sealed by lids. An area of the flow channel in the cooling pipes is thus reduced. Heat conductivity on the cooling surface of the cooling pipes is increased in the high thermal load heat receiving plate having such a structure. Accordingly, temperature elevation of the armour tile can be ...
Barsebaeck 1 was closed on 30 November 1999. Barsebaeck's output of approximately 4 TWh per year will primarily be replaced by imports from coal-fired plants in Denmark and Germany. During the year, the closure of Swedish fossil-fired condensing power stations continued. With that, over 3,000 MW of peak-load power has been shut down during recent years. Consequently, situations entailing shortages of power can arise. On the deregulated electricity market, it is only the system operators that have a satisfactory overview of the overall electricity balance. The Swedish Power Association has thus lobbied the government as regards the need to elucidate Svenska Kraftnaet's responsibility. In a governmental decision from December, Svenska Kraftnaet was given the task of, among other things, monitoring the available capacity during peak loads and developing market instruments that can contribute to safeguarding the availability of ...
A joint experimental and theoretical analyses based on the grounds of DFT anharmonic potential and the use of a variational method allow us to revisit and assign the gas phase spectra of vinylarsine in the mid-IR area until 6300cm-1. Several weak and very weak bands corresponding to overtones and combinations are newly observed and assigned in complement to the fundamental bands.
Resistance exercise has been widely reported to have positive rehabilitation effects for patients with neuromuscular and orthopaedic conditions. This paper presents an optimal design of magneto-rheological fluid dampers for variable resistance exercise devices. Adaptive controls for regulating the resistive force or torque of the device as well as the joint motion are presented. The device provides both isometric and isokinetic strength training for various human joints.
Through a comprehensive and aggressive research program Consolidated Edison Company of New York, Inc. (Con Edison) has designed, developed, and installed several new products to address the environmental impact of dielectric fluid from pipe-type cable systems. These include: On Line Leak Detection, Leak Location, Retractable Flow Direction Indicator, Full Stop Joints, and Transition Joints. This paper describes the application of the aforementioned products on the Con Edison underground transmission system.
In recent years there has been a renewed interest in the treatment of quantum mechanics in terms of joint distribution functions, i.e. functions of momentum and position coordinates p and q. The author considers j.d.f. in the sense of classical probability theory of a stochastic variable. The j.d.f. is then interpreted as the probability that the variables p and q have certain values, the variables being considered as a property possessed by the object system. This formalism is used to provide a unified description of bradyons and tachyons. (Auth.).
According to the present invention, a joined product is at least two ceramic parts, specifically bi-element carbide parts with a bond joint therebetween, wherein the bond joint has a metal silicon phase. The bi-element carbide refers to compounds of MC, M.sub.2 C, M.sub.4 C and combinations thereof, where M is a first element and C is carbon. The metal silicon phase may be a metal silicon carbide ternary phase, or a metal silicide.
A report is presented of a hearing conducted before the Joint Committee on Atomic Energy on August 27, 1976, to discuss the legal implications for reactor licensing resulting from court challenges to procedures for assessing the environmental impact of radioactive waste disposal. (DG)
A billet of low-density carbon-bonded carbon fiber (CBCF) composite is machined into a desired attenuator or load element shape (usually tapering). The CBCF composite is used as a free-standing load element or, preferably, brazed to the copper, brass or aluminum components of coaxial transmission lines or microwave waveguides. A novel braze method was developed for the brazing step. The resulting attenuator and/or load devices are robust, relatively inexpensive, more easily fabricated, and have improved performance over conventional graded-coating loads.
Recently, weight reduction of vehicles has been of great interest, and consequently, the use of low-density materials in the automotive industry is increasing every year. Materials should not be substituted such a way that material of component parts is simply changed because there is a problem in achieving stiffness and strength. To achieve these requirements, the automobile should be redesigned totally. Aluminum spaceframe is rapidly being adopted as a body structure for accommodating lightness, stiffness and strength requirement. In aluminum spaceframe manufacturing, it is often required to join aluminum tube. But there are few suitable methods for joining aluminum tube, so that much interest has been focused on testing suitable joining methods. Joining by electromagnetic forming(EMF) can be useful method in joining aluminum tube, which offers some advantages compared with the conventional joining method. In this paper, joining by EMF was investigated as a pre-study for applying an ...
Transition joints in power plants between ferritic steels and austenitic stainless steels suffer from a mismatch in coefficients of thermal expansion (CTE) and the migration of carbon during service from the ferritic to the austenitic steel. To overcome these, nickel-based consumables are commonly used. The use of a trimetallic combination with an insert piece of intermediate CTE provides for a more effective lowering of thermal stresses. The current work envisages a trimetallic joint involving modified 9Cr-1Mo steel and 316LN austenitic stainless steel as the base materials and Alloy 800 as the intermediate piece. Of the two joints involved, this paper describes the choice of welding consumables for the joint between Alloy 800 and 316LN. Four consumables were examined: 316, 16-8-2, Inconel 82 and Inconel 182. The comparative evaluation was based on hot cracking tests and estimation of mechanical ...
Grid connected photovoltaic systems is one of the most promising applications of photovoltaic systems. These systems are employed in applications where utility service is already available. In this case, there is no need for battery storage because grid power may be used to supplement photovoltaic systems (PV) when the load exceeds available PV generation. The load receives electricity from both the photovoltaic array and the utility grid. In this system, the load is the total electrical energy consumption. The main objective of the present work is to optimize the electrical load pattern in Kuwait using grid connected PV systems. In this situation, the electric load demand can be satisfied from both the photovoltaic array and the utility grid. The performance of grid connected photovoltaic systems in the Kuwait climate has been evaluated. It was found that the peak ...
An effect of load conditions on Corrosion Fatigue Crack Propagation (CFCP) behavior of High Performance Steel (HPS) under seawater environment was investigated. Fatigue crack propagation tests under several load conditions including stress ratio and load frequency were conducted in air and 3.5% NaCl solution environments. Corrosion/fatigue ratio factor, C/F, particularly was defined to analyze the effect of such conditions. As shown in the results, a decrease of load ratio and frequency leads to an increase of C/F factor. Consequently, under lower loading frequency and stress ratio, the seawater condition causes much more significant effect on CFCP behavior of HPS.
Purpose Nonpoint sources (NPS) pollution has been an important cause for water quality impairment worldwide. To take the temporal variations of both NPS pollution and in-stream attenuation into consideration, an inverse modeling approach and the load duration curve (LDC) method were combined for variable nutrient total maximum daily load (TMDL) development. Methods Water quality and hydrological parameters were monitored monthly along the ChangLe River system in 2004?2008. The catchment NPS export load (EL) and TMDL for total nitrogen (TN) were estimated by the inverse format of an existing stream nutrient transport equation. The LDC method was used to describe the variability of EL, TMDL, requiring load (RLR) and percent (the ratio between the RLR and the EL, RPR) reduction, and then to s...
On June 2, 1992, Landers` earthquake struck the Solar Electric Generating System II, located in Daggett, California. The 30 megawatt power station, operated by the Daggett Leasing Corporation (DLC), suffered substantial damage due to structural failures in the solar farm. These failures consisted of the separation of sliding joints supporting a distribution of parabolic glass mirrors. At separation, the mirrors fell to the ground and broke. It was the desire of the DLC and the Solar Thermal Design Assistance Center (STDAC) of Sandia National Laboratories (SNL) and to redesign these joints so that, in the event of future quakes, costly breakage will be avoided. To accomplish this task, drawings of collector components were developed by the STDAC, from which a detailed finite element computer model of a solar collector was produced. This nonlinear dynamic model, which consisted of over 8,560 degrees of freedom, underwent model reduction to form a ...
Under the current design philosophy, reactor structures are to be designed to withstand large inelastic deformation caused by strong and severe ground motion. The design of the main structural elements and their connections are to be such that they always fail in ductile mode. This will ensure large energy absorption capacity of the structures under seismic excitation and avoid sudden and brittle failure of the structure. Over the years, a number of experimental investigations have been carried out on RC beam- column joints to study their behaviour and strength. However, these studies mostly pertain to small scale joints of moment resisting frame of residential buildings and commercial complexes. Information on full scale joints existing in NPP structures are scanty. Therefore, experimental programme was planned in the laboratory to construct identical large sized joints with the same reinforcement ...
Strong support for the existence of catalytically-active, sub-surface oxygen is proposed. The existence of two types of sub-surface oxygen was determined by thermal-desorption spectroscopy (TDS). The first is termed O{sub {beta}} and is characterized by a board thermal-desorption peak centered at approximately 773 K. The second is referred to as O{sub {gamma}} and is characterized by an unsaturated thermal desorption signal beginning at approximately 873 K. O{sub {gamma}} is assigned to oxygen which is incorporated in the uppermost layers of low-indexed terminating crystal structures such as (111) formed as a result of thermal reordering. O{sub {beta}} diffusion occurs most likely via interstitial jumping and O{sub {gamma}} via interstitialcy diffusion. Both CH{sub 4} conversion and C{sub 2} selectivity improve with time on stream. This improvement in catalytic performance correlates well with surface facetting and particle rupture, which occurs as a result of ...
Performance of SRF cavities are limited by non-linear localized effects. The variation of local material characters between "hot" and "cold" spots is thus of intense interest. Such locations were identified in a BCP-etched large-grain single-cell cavity and removed for examination by high resolution electron microscopy (SEM), electron-back scattering diffraction microscopy (EBSD), optical microscopy, and 3D profilometry. Pits with clearly discernable crystal facets were observed in both "hotspot" and "coldspot" specimens. The pits were found in-grain, at bi-crystal boundaries, and on tri-crystal junctions. They are interpreted as etch pits induced by surface crystal defects (e.g. dislocations). All "coldspots" examined had qualitatively low density of etching pits or very shallow tri-crystal boundary junction. EBSD revealed the crystal structure surrounding the pits via crystal phase orientation mapping, while 3D profilometry gave information on the depth and size ...
We report on recent progress and improvements in the metal-organic chemical vapor deposition (MOCVD) growth of mid-infrared lasers and using a high speed rotating disk reactor (RDR). The devices contain AlAsSb active regions. These lasers have multi-stage, type I InAsSb/InAsP quantum well active regions. A semi-metal GaAsSb/InAs layer acts as an internal electron source for the multi-stage injection lasers and AlAsSb is an electron confinement layer. These structures are the first MOCVD multi-stage devices. Growth in an RDR was necessary to avoid the previously observed Al memory effects found in conventional horizontal reactors. A single stage, optically pumped laser yielded improved power (greater than 650 mW/facet) at 80K and 3.8um. A multi-stage 3.8-3.9um laser structure operated up to T=170K. At 80K, peak power greater than 100mW and a high slope- efficiency were observed in gain guided lasers.
The world fusion program has advanced to the stage where it is appropriate to construct a number of devices for the purpose of burning DT fuel. In these next-generation experiments, the expected flux and fluence of 14 MeV neutrons and associated gamma rays will pose a significant challenge to the operation and diagnostics of the fusion device. Radiation effects include structural damage to materials such as vacuum windows and seals, modifications to electrical properties such as electrical conductivity and dielectric strength and impaired optical properties such as reduced transparency and luminescence of windows and fiber optics during irradiation. In preparation for construction and operation of these new facilities, the fusion diagnostics community needs to work with materials scientists to develop a better understanding of radiation effects, and to undertake a testing program aimed at developing workable solutions for this multi-faceted problem. A unique ...
Recent research has shown that biologically inspired approaches to materials synthesis and self-assembly, hold promise of unprecedented atomic level control of structure and interfaces. In particular, the use of organic molecules to control the production of inorganic technological materials has the potential for controlling grain structure to enhance material strength; controlling facet expression for enhanced catalytic activity; and controlling the shape of nanostructured materials to optimize optical, electrical and magnetic properties. In this work, we use organic molecules to modify silver crystal shapes towards understanding the metal-organic interactions that lead to nanoparticle shape control. Using in situ electrochemical AFM (EC-AFM) as an in situ probe, we study the influence of a cationic surfactant cetyltrimethylamminobromide (CTAB) on Ag growth during electrochemical deposition on Ag(100). The results show that the organic surfactant promotes the ...
The purpose of this investigation was to determine the association between gender and the prevalence and incidence of patellofemoral pain syndrome (PFPS). One thousand five hundred and twenty-five participants from the United States Naval Academy (USNA) were followed for up to 2.5 years for the development of PFPS. Physicians and certified athletic trainers documented the cases of PFPS. PFPS was defined as retropatellar pain during at least two of the following activities: ascending/descending stairs, hopping/jogging, prolonged sitting, kneeling, and squatting, negative findings on examination of knee ligament, menisci, bursa, and synovial plica, and pain on palpation of either the patellar facets or femoral condyles. Poisson and logistic regressions were performed to determine the association between gender and the incidence and prevalence of PFPS, respectively. The incidence rate for PFPS was 22/1000 person-years. Females were 2.23 times (95% CI: 1.19, 4.20) more ...
A multi-faceted research program has been performed to investigate in detail several aspects of free and forced convective cooling of underground electric cable systems. There were two main areas of investigation. The first one, reported in Volume 1, dealt with the fluid dynamic and thermal aspects of various components of the cable system. In particular, friction factors for laminar flow in the cable pipes with various configurations were determined using a finite element technique; the temperature distributions and heat transfer in splices were examined using a combined analytical numerical technique; the pressure drop and heat transfer characteristics of cable pipes in the transitional and turbulent flow regime were determined experimentally in a model study; and full-scale model experimental work was carried out to determine the fluid dynamic and thermal characteristics of entrance and exit chambers for the cooling oil. The second major area of activity, ...
A multi-faceted research program has been performed to investigate in detail several aspects of free and forced convective cooling of underground electric cable systems. There were two main areas of investigation. The first one reported in this volume dealt with the fluid dynamic and thermal aspects of various components of the cable system. In particular, friction factors for laminar flow in the cable pipes with various configurations were determined using a finite element technique; the temperature distributions and heat transfer in splices were examined using a combined analytical numerical technique; the pressure drop and heat transfer characteristics of cable pipes in the transitional and turbulent flow regime were determined experimentally in a model study; and full-scale model experimental work was carried out to determine the fluid dynamic and thermal characteristics of entrance and exit chambers for the cooling oil. The second major area of activity, ...
The growth of epitaxial MnO(100) and MnO(111) layers on Pd(100) surface has been investigated by spot-profile analysis low-energy electron diffraction, dynamic atomic force microscopy, photoemission and high-resolution electron energy loss spectroscopy, and density functional theory. We have found that despite the large lattice mismatch to the Pd(100) substrate, the MnO(100) layers are kinetically stabilized at low temperatures (?350 deg. C) and at oxygen pressures between 2x10-7 and 5x10-7 mbar. Annealing in ultrahigh vacuum at 650 deg. C or, alternatively, deposition of manganese metal in oxygen pressure -7 mbar causes the transformation of the MnO(100) to a polar MnO(111) surface, which is decorated by triangular pyramids with (100) side facets. It is suggested that the growth of MnO(111) layers is energetically preferred over MnO(100) due to the epitaxial stabilization at the metal-oxide interface.
III--V based devices such as field effect transistors, heterojunction bipolar transistors, and lasers often have surface leakage and thermal degradation problems due to surface states which pin the Fermi level to the midgap. Sulfur based passivation processes are known to improve device performance by altering surface-state densities. We have developed a voltage-controlled anodic sulfur passivation scheme using Na[sub 2]S dissolved in ethylene glycol. Our process has repeatedly produced a [similar to]25% improvement in peak output power near the catastrophic damage limit in visible ([lambda]=670 nm) AlGaInP edge-emitting lasers. The threshold current density before and after passivation, and the [ital I]--[ital V] characteristics before and after catastrophic failure, were essentially unchanged indicating that passivation raises the threshold for facet damage.
III--V based devices such as field effect transistors, heterojunction bipolar transistors, and lasers often have surface leakage and thermal degradation problems due to surface states which pin the Fermi level to the midgap. Sulfur based passivation processes are known to improve device performance by altering surface-state densities. We have developed a voltage-controlled anodic sulfur passivation scheme using Na_2S dissolved in ethylene glycol. Our process has repeatedly produced a #approx#25% improvement in peak output power near the catastrophic damage limit in visible (#lambda#=670 nm) AlGaInP edge-emitting lasers. The threshold current density before and after passivation, and the I--V characteristics before and after catastrophic failure, were essentially unchanged indicating that passivation raises the threshold for facet damage.
Tantalum and tantalum-based thin films have gained precedence as the diffusion barrier for copper interconnects used in the latest generation of integrated circuits (ICs). The paper presents insight and observations on the covariance of texture and grain size of wrought tantalum sputtering targets and their influence on sputtering performance. Previous studies involving deposition trials of tantalum targets of varying metallurgical character had demonstrated that both grain size and textural homogeneity is critical for assuring reliable sputtering performance of tantalum. Subsequently, a model had been proposed to prescribe how localized texture bands and orientation clusters in tantalum are effectively resistant to sputter erosion. In this paper, results of atomic force microscopy (AFM) and orientation imaging microscopy (OIM{sup TM}) analyses on the eroded surface of a tantalum sputtering target are presented. Initial findings support the model's hypothesis regarding the ...
A salient facet of Axelrod's model for culture dissemination or social influence is the existence of many multicultural absorbing states. The dependence of the number $C$ of different, coexisting cultures on the size $A$ of the territory or, equivalently, on the number of agents -- the culture-area relation -- is investigated through extensive simulations. This relation exhibits a strong qualitative dependence on the two parameters of the model, namely, the number $F$ of culture features and the number $q$ of values that each feature can take on. We find that a non-monotonous culture-area relation, for which the number of cultures decreases when the area grows beyond a certain size, occurs for $q$ smaller than a threshold value $q_c = q_c (F)$ provided that $F \\geq 3$. In the limit of infinite area, this threshold value signals the onset of a discontinuous phase transition between a homogeneous regime for which C=1, and a completely disordered regime for which $C ...
Magnetic coupling between two or more metal centers is an important facet of d- and f-block transition metal chemistry due to its implications in chemical bonding. With respect to actinide metals, magnetic coupling between polymetallic actinide centers is less well-known. Of the few documented examples, only one bimetallic uranium(V) complex, [(MeC{sub 5}H{sub 4}){sub 2}U]{sub 2}[{mu}-1,4-N{sub 2}C{sub 6}H{sub 4}] (1), has unequivocally demonstrated antiferromagnetic coupling. This complex employs a {pi}-conjugated 1,4-phenylenedimide ligand system which bridges the two f{sup 1}-metal centers and enables antiferromagentic coupling between unpaired f-e1ectrons residing in a {pi}-symmetry orbital. In this communication, we report the synthesis of a dimeric bis(imido) uranium(V) iodide complex and demonstrate with magnetic susceptibility measurements and density functional theory (DFT) calculations that the f{sup 1}-uranium centers display antiferromagnetic coupling ...
Research highlights: #-># The building occupancy affecting the cooling load prediction is studied. #-># PENN model is adopted in this study for predicting the building cooling load. #-># Statistical approach is adopted to result a less prejudice prediction performance. #-># Results show that occupancy data can significantly improve the prediction. -- Abstract: Building cooling load prediction is one of the key factors in the success of energy-saving measures. Many computational models available in the industry today have been developed from either forward or inverse modeling approaches. However, most of these models require extensive computer resources and involve lengthy computation. This paper discusses the use of data-driven intelligent approaches, a probabilistic entropy-based neural (PENN) model to predict the cooling load of a building. Although it is common knowledge that the presence ...
Magnetic resonance imaging has proven an invaluable method in the diagnosis of joint diseases associated with osteonecrotic, inflammatory, traumatic and degenerative processes. At the clinical level, it has an important role in decisions about the method of treatment and evaluations of the therapeutic success. When the merits of MRT are balanced against those of conventional radiography including tomography and CT, which both ensure better spatial resolution in the visualisation of cortical and spongy bone structures, it becomes quite evident that MRT must not be regarded as an alternative method of imaging but as one that can be used additionally to obtain the most information for the diagnosis of arthropathy. The question as to whether new pulse sequences (snap shots) or invasive techniques like intra-articular injection of paramagnetic substances (MR arthrography) are likely to become routine procedures in the detection of joint diseases ...
Magnetic pulse welding is a solid state impact welding process, similar to explosive welding, which produces metallurgical bond by oblique high-speed impact between two metal bodies. This violent impact removes the metal surface oxide layers and then joins the two atomic level clean metal surfaces together by the incidental compression pressure. The impact velocity is at 200?400?m/s and the being welded metal surface undergoes severe plastic deformation with strain rate in the order of 106?107?s?1. The ultrafine-grained structure was observed on the welded interface. This article studied two types of similar material lap joint interfaces and the base metals were aluminum alloy 6061 and copper alloy 110. Nano-indentation testing shows that the welded interfaces have significantly greater ha...
In this paper, for an acceleration of utilization of magnesium alloy which is being interested in recent years, friction welding of AZ31 magnesium alloy was carried out, and the joint performance was discussed in relation to the deformation heat input in the upset stage and upset loss as a evaluation factor. Where, the deformation heat input in the upset stage is mechanical work represented by the product of upset speed and axial pressure. As a result, it was made clear that the friction welding of AZ31 magnesium alloy was easy in the atmosphere, and good welded joints without a non- adhesion area at the weld interface could de obtained. Moreover, the evaluation factors discussed were possible to evaluate to joint performance. (orig.)
During sporting events, injured athletes often return to competition after icing because of the reduction in pain. Although some controversy exists, several studies suggest that cryotherapy causes a decrease in muscle activity, which may lead to a higher risk of injury upon return to play. The purpose of this study was to investigate the effect of a 20-min knee joint cryotherapy application on the electromyographic activity of leg muscles during a single-leg drop jump in twenty healthy subjects, randomly assigned to an experimental and a control group. After the pre-tests, a crushed-ice bag was applied to the knee joint of the experimental group subjects for 20min, while the control group subjects rested for 20min. All subjects were retested immediately after this period and retested again...
The progression of hip dysplasia was investigated in 116 military working dogs. Serial pelvic radiographs were graded for degree of dysplasia and degenerative joint disease (DJD). Norberg angles, angles of inclination, and joint space widths were measured. There was a significant correlation between the Norberg angle and the degree of dysplasia (p less than 0.0001). Angles of inclination and joint space width measurements did not demonstrate a correlation to canine hip dysplasia. Dysplastic dogs had a significant estimated risk for development of DJD compared to normal dogs (p less than 0.0001; odds ratio of 70.2). Dogs with normal hip conformation at 24 months of age or older did not develop moderate nor severe DJD. PMID:8875357
The adverse effects and diagnostic accuracy of thallium-201 myocardial SPECT after intravenous infusion of adenosine triphosphate (ATP) were studied and compared with SPECT examinations with other type of loading. The subjects of the study were 147 patients with or without coronary artery disease, who underwent some type of loading SPECT and coronary arteriography (CAG) within 30 days. Myocardial ischemia was evaluated qualitatively in SPECT and was compared with CAG for the diagnostic accuracy of coronary artery disease. The degree of myocardial uptake defect was also calculated semiquantitatively using visual scoring method and compared with coronary artery severity score. The adverse effects occurred in 46.7% of ATP loading SPECT which was more frequent that DIP loading SPECT, but all of them were transient and mild. As for the diagnostic ability the ATP loading SPECT was as ...
VACUTAINER PPT plasma preparation tubes were evaluated to determine the effects of various handling and shipping conditions on plasma human immunodeficiency virus (HIV) load determinations. Plasmas...Full Text Available
This paper presents part-load evaluation of a natural gas-fired chemical looping combustion (CLC) combined cycle with CO2 capture. The novel combined cycle employs an air-based gas turbine, a CO2-turbine and a steam turbine cycle. In this combined cycle, the CLC reactors replace combustion chamber of the gas turbine. The proposed combined cycle has a net plant efficiency of about 52.2% at full-load, including CO2 compression to 200 bar. The part-load evaluation shows that reducing the load down to 60% results in an efficiency drop of 2.6%-points. However, the plant shows better relative part-load efficiency compared to conventional combined cycles. The pressure in CLC-reduction and -oxidation reactors is balanced by airflow control, using a compressor equipped with variable guide vanes. A combination of control strategies is discussed for plant start-up and shutdown and for ...
There has been great interest in understanding the methods by which collagen-based load-bearing tissue is constructed, grown and maintained in vertebrate animals. To date, the responsibility for this...Full Text Available
In regions of high bone loading, the mechanoresponsive osteocytes inhibit osteoclastic bone resorption by producing signaling molecules. One possible candidate is matrix extracellular phosphoglycoprotein...Full Text Available
This document presented the results of a full-scale pile load tests conducted on helix pile foundations supporting power transmission towers in northern Manitoba. The site conditions were described along with pile installation and the performance of the foundations. The pile load tests were carried out in 2 different soil conditions, notably soft to firm clays and stiff high plastic clays with silt varves. The performance of the helix pile foundations were examined under axial compressive and axial tension (uplift) loading conditions. The results of the compressive load tests were presented in the form of load settlement curves while the results of the uplift load tests were presented in the form of load displacement curves. Both types of load tests in soft or stiff clays showed the suitability of helical pile ...
A method for recycling laser flashlamp radiation in selected wavelength ranges to decrease thermal loading of the solid state laser matrix while substantially maintaining the pumping efficiency of the flashlamp.
The association of dietary glycaemic index (GI) and glycaemic load (GL) with cardiovascular diseases has been examined in several populations with varying results. We tested the hypothesis that...Full Text Available
Jun 16, 2011 ... Results indicated that fuel loadings averaged 24.05 Mg ha 1 in 2004–2006. Forest litter decreased from wetter to drier forest life zones. ...
Thermodynamic Stable Metal Compositions for Improvement of an Operational Safety of Constructional Materials under Conditions of Multifactor Loadings of an Aggressive Environment
disciplinary methods were used to independently determine the aerodynamic loads, the thermal response, and strardural performance of the hydrogen cooled ...
To date few reports have provided direct comparison of psychosocial vulnerability and resources among youth with victimization and perpetration histories. Within a racially diverse, high-risk...Full Text Available
... Headquarters 5th Brugade 78th Division (Ts) ... 2nd Battalion 20th Special Forces Company B ... 29th Corps Personnel Serves Hq Joint Task Force Aug ...
... NE Mall Room B-607, EPA Headquarters, 401 M ... formally adopted and initiated a joint strategy for ... CLI kick-off Partner and Task Force meeting. ...
Isokinetic training and assessment of the knee joint has been the mainstay of rehabilitation, especially in patients with anterior cruciate ligament deficiency. Besides the original shin pad used, the...Full Text Available
The Space Task Group in its study of future directions in space, with ..... almost $6 billion and a peak civil service and contractor work force of 420000 people. ..... space organizations permitting assumptions of primary or joint responsibility for ...
Washington, DC -07/24/09 Photo: Secretary Clinton and Iraqi Prime Minister al-Maliki at HCC Bilateral; Washington, DC -07/24/09 Photo: Secretary Clinton at Joint Press...
Haemophilia, the commonest hereditary bleeding disorder, arises because of the absence of, decrease in, or deficient functioning of plasma coagulation factor VIII or factor IX. With rare exceptions,...Full Text Available
The corrosion behaviour of friction stir welded (FSW) joints of AA 5083 has been compared to that of MIG welded joints. Pitting and stress corrosion cracking (SCC) resistance in 3.5% NaCl + 0.3 g/l H{sub 2}O{sub 2} and in EXCO (4 M KCl + 0.5 M KNO{sub 3} + 0.1 M HNO{sub 3}) solutions has been determined at 25 C. SCC susceptibility was evaluated by slow strain rate tests (SSRT), at a strain rate of 1 x 10{sup -6}s{sup -1}. Welds obtained by FSW technique showed a higher corrosion resistance in EXCO solution and a lower pitting tendency than the base alloy. Electrochemical measurements (corrosion potential measurements, polarization curves recording) evidenced that FSW weld was cathodic to base alloy. FSW joints were not susceptible to SCC in both test solutions, whereas MIG joints cracked in both solutions. (orig.)
This report is designed to cover the overall Operation Castle radiological safety matters from the viewpoint of those issues of direct concern to Headquarters, Joint Task Force Seven. It was written for the express purpose of assisting in the development ...
This report is designed to cover the overall Operation Castle radiological safety matters from the viewpoint of those issues of direct concern to Headquarters, Joint Task Force Seven. It was written for the express purpose of assisting in the development ...
A study of the joint evolution of the normal- and neutron-star components of massive binaries opens with a classification scheme and the analytic expressions to be applied in Paper II for computer simulation of the observable properties of such systems.
The relationships between muscle tensions, jaw motions, bite and joint forces, and craniofacial morphology are not fully understood. Three-dimensional (3-D) computer models are able to combine anatomical...Full Text Available
Metallic O-ring or Helicoflex seals can prevent relaxation and provide greater resilience than composite seals, helping to keep joints leaktight. Their characteristics and applications in the nuclear industry are outlined. (Author).
... We also toured a Trident submarine at Kings Bay, Ga. "During the weekend at the Joint Interagency Task Force Headquarters in Key West, Fla., we ...
... The high resolution imagery , collected over Rio de Janeiro, Brazil, included a mixture of large commercial buildings and private houses, as well as the airport and some community parks. 10/08/11 Read more Top EU R&D companies expect a 5% ...
The article reviews the Rothschild First Interim Report on the future of the British Coal Industry and British Coal Corporation. The report incorporates work undertaken by the Joint Working Groups set up with British Coal. The article points out various errors in the report and criticizes its conclusions.
Cytokine regulation of synovial fluid (SF) lubricants, hyaluronan (HA), and proteoglycan 4 (PRG4) is important in health, injury, and disease of synovial joints, and may also provide powerful regulation...Full Text Available
We describe two cases of septic arthritis occurring in association with lower urinary tract infection in elderly men. In both cases the organism isolated from both the joint and the urine was Staphylococcus...Full Text Available
In view of the situation that aging of boiler components proceeds and some `Type IV` cracking incidents are reported recently, the development of an accurate remaining life evaluation method for boiler weldment parts is an important subject for the utilities. In this study, simulated materials with coarse and fine grain microstructures in a weldment heat affected zone were produced, and their high temperature strength properties were evaluated. The strength property of the weld joint was also discussed based on the experimental and analytical results. It was found that the creep rupture strength of the fine grain material was as low as 1/2 of the base metal and as 1/5 of the coarse grain material, and the weld joint ruptured at the fine grain region in a shorter period than the base metal as the applied stress level decreased. Many grainboundary creep cavities were also observed in the fine grain region. A creep deformation analysis by FEM ...
Tendon reconstruction using grafts often results in adhesions that limit joint flexion. These adhesions are precipitated by inflammation, fibrosis, and paucity of tendon differentiation signals...Full Text Available
Officers receive service-specific education and undergo experiences within their components that provide the expert knowledge that enables them to operate in their respective military departments. Given the Department of Defense (DoD) emphasis on service ...
Static task intensity–endurance time (ET) relationships (e.g. Rohmert's curve) were first reported decades ago. However, a comprehensive meta-analysis to compare experimentally-observed...Full Text Available
Prophylactic knee braces are designed to prevent and reduce the severity of ligamentous injuries to the knee. Conflicting evidence is reported concerning their efficacy. The purpose of this study was...Full Text Available
The goal of this study was to evaluate topics used to troubleshoot circuit boards with known or suspected thermally intermittent components. Failure modes for thermally intermittent components are typically mechanical defects, such as cracks in solder paths or joints, or broken b...
Seventy seven patients with soft tissue shoulder lesions including adhesive capsulitis and disorders of the rotator cuff and acromioclavicular joint were admitted to a trial comparing two different...Full Text Available
This study investigates the doctrinal guidance available to a corps headquarters if required to serve as ajoint task force headquarters and simultaneously be required to warfight the corps. The study contends that a corps being required to simultaneously ...
ObjectiveTo estimate the joint effect of a multifaceted access intervention on primary care physician (PCP) productivity in a large, integrated prepaid group practice.Data...Full Text Available
...undertake missions and tasks (on either a...Secretary of Defense to task the DoD Components...the Chairman of the Joint Chiefs of Staff any commitment of military forces assigned to the Unified... (9) Military forces employed in MSCA...approval from higher headquarters, local military...
(General Stafford) was selected as chair for the Task Force based on his expertise .... a large foreign customer base that includes joint working agreements with Russia, the .... NASA Headquarters management advocates the Jorge Scientific ...
This document provides structural load requirements and their basis for maintaining the structural integrity of the Hanford Single-Shell Tanks during waste feed delivery and retrieval activities. The requirements are based on a review of previous requirements and their basis documents as well as load histories with particular emphasis on the proposed lead transfer feed tanks for the privatized vitrification plant.
Cyclic strength of #alpha#+#beta#-titanium alloy BT3-1 is studied under load frequencies of 33 and 300 Hz. The increase in the cyclic strength with growing frequency is caused by formation of FCC interphase layers of titanium hydrides. Their formation is one of possible ways of raising the fatigue strength of titanium alloys. Peculiarities of FCC interlayer formation in #alpha#+#beta# phases under loading frequency variation are revealed.
The results of an investigation into the behavior of adhesively bonded doubler splices of two composite material sandwich panels are presented. The splices are studied from three approaches: analytical; numerical (finite elements); and experimental. Several parameters that characterize the splice are developed to determine their influence upon joint strength. These parameters are: doubler overlap length; core stiffness; laminate bending stiffness; the size of the gap between the spliced sandwich panels; and room and elevated temperatures. Similarities and contrasts between these splices and the physically similar single and double lap joints are discussed. The results of this investigation suggest several possible approaches to improving the strength of the sandwich splices.
We report a case of stress fracture of the clavicle associated with sternocostoclavicular hyperostosis. A 60-year-old man sustained a stress fracture of the right clavicle with no history of trauma. On radiography, hyperostosis of the anterior chest wall and ankylosis of the sternoclavicular joint were evident in addition to the fracture. Fracture healing was uneventful after 2.5 months. Ankylosis of the sternoclavicular joint may have caused increased stress at the midshaft of the clavicle by daily activity or minor trauma. Such a fracture is a rare complication of sternocostoclavicular hyperostosis. (orig.)
In the last 40 years, significant advances have been made in the understanding of the neurophysiologic processes involved in the experience of trauma and pain. This knowledge, together with the rapid growth and understanding in the behavioral health sciences, has expanded to include a much better appreciation of how these fields are converging and contribute to a process called neuroplasticity. These basic mechanisms common to all patients have important implications for clinical outcome and for improving clinical practice. This article is written for clinicians who manage patients with sacroiliac joint dysfunction, a specific type of nonspecific low back pain.
The utilization of nuclear medicine bone scanning examinations early in the diagnostic process allows physicians to render prompt and correct treatment in urgent or difficult athletic cases. Bone scanning should be performed for athletic injuries whenever (1) x-rays are normal but bone or joint pain persists; (2) x-rays are positive but it cannot be determined if the findings are acute or chronic; (3) soft-tissue injuries present and x-rays are not useful; and (4) bone pain or joint impairment present without a history of trauma.89 references.
The activities and results of a Small Business Innovation Research Phase II project entitled ''Rapid Tools for Joint Inversion and Imaging'' are presented. Research and development on three-dimensional methods to recover distributions of material property values from sparse data are reported. Innovations using artificial neural networks and extended Kalman filtering are described. The report also covers investigations on upscaling and downscaling, segmentation for data processing, and applications to ground penetrating radar and geohydraulic tomography.
The integrity of helium circulation loop flanged joints has been attracting recent attention as a design problem, in the development of high-temperature facilities incorporating helium loops (e.g., the VRG-50 pilot nuclear facility). Elevated temperatures and pressures, and the radiation environment, impose additional requirements on sealant materials. This applies first and foremost to rubber seals, which have found widespread favor on account of its excellent elasticity, its ability to spontaneously conform to possible changes in the clearance in the seal assembly, and the low compressive stresses developed in the flange joint assembly.
Proposed ductile fracture toughness parameters from tensile tests have been successfully used to determine the post-weld heat treatment temperature for an alloy 800/(9Cr-1Mo) steel dissimilar metal weld joint that is optimum with respect to accelerated aging, which simulates service conditions. This approach proved superior to using microstructural analysis, microhardness profiles, and conventional tensile properties. (author).
It has become necessary to investigate the feasibility and desirability of joint coking of residues from the processing of petroleum and shale oil. Experiments have been performed on different types of feedstocks: a shale oil residue (SO) with an initial boiling point of 350/sup 0/C, obtained by thermal destruction of Bulgarian shales with a solid heat-carrier; a pyrolysis tar from the production of ethylene; extracts obtained in solvent treatment of petroleum oils, namely extracts from medium-viscosity lube distillate, viscous distillate, and residual lube stock; and asphalt obtained in deasphalting. Each of the petroleum products was blended with the SO in a 1/1 ratio.
The authors measured the absorption of CO{sub 2} in alkaline 0.5 M/0.5 M sodium carbonate/bicarbonate buffers containing either saccharose and sodium arsenite or saccharose and formaldehyde. Absorption enhancement increased upon increasing the concentration of either of the catalysts, but the joint action of the two was always less than the sum of their individual effects, the difference being a function of the acidities and concentrations of the catalysts and the pH of the carbonate/bicarbonate buffer solution
The magnetoresistance in an FeNi submicron-structure comprising two wires of 80 and 200 nm in width connected in series was measured at 77 K. When the external magnetic field was applied parallel to the wire axis, two switching fields corresponding to the distinct coercive force of the two wires were observed. When the external magnetic field was applied at an angle of {theta}>30 deg. to the wire axis one switching field was observed, indicating simultaneous magnetization reversal in both wires. This indicates that the domain-wall trapping around the joint can be controlled systematically in terms of the direction of the external magnetic field.
The integrity of a pipeline system is determined by its weakest links which may be the joints. Heat fusion is the most common method for joining gas distribution polyethylene (PE) piping. There are procedural, thermal, and mechanical aspects of making fusion joints. Acceptable procedural aspects, such as heater calibration and cleanliness, can be assured by rigorous training and certification of the operators. Thermal and mechanical aspects consist of specifying joining conditions such as the heater temperature, heating time, and joining pressure. In the absence of procedural errors, the strength of a fusion joint should depend on the pipe material, pipe dimensions, and the thermal and mechanical joining conditions. Socket heat fusion was studied both experimentally and analytically to determine how the strength of the joint varied with the conditions under which it was made. The standard tensile impact ...
The integrity of a pipeline system is determined by its weakest links which may be the joints. Heat fusion is the most common method for joining gas distribution polyethylene (PE) piping. There are procedural, thermal, and mechanical aspects of making fusion joints. Acceptable procedural aspects, such as heater calibration and cleanliness, can be assured by rigorous training and certification of the operators. Thermal and mechanical aspects consist of specifying joining conditions such as the heater temperature, heating time, and joining pressure. In the absence of procedural errors, the strength of a fusion joint should depend on the pipe material, pipe dimensions, and the thermal and mechanical joining conditions. Socket heat fusion was studied both experimentally and analytically to determine how the strength of the joint varied with the conditions under which it was made. The standard tensile impact ...
In the feasibility study on commercialized FBR systems, the application of 12Cr steel, with its physical properties and high-temperature strength properties, as structural material is considered in order to greatly reduce construction costs by compacted instruments and structures. In this report, creep, fatigue and the creep-fatigue properties of Mod.9Cr-1Mo steel forging (thickness 550mm) weld, representing conventional steels, were evaluated in order to obtain the needed basic data for the evaluation of the high-temperature strength of 12Cr steel weld. The results obtained are as follows: (1) Metal suitable for HAZ was made by applying thermal treatment to simulate the thermal hysteresis during welding to clearly define creep and fatigue properties in a HAZ softened zone. (2) Creep strength of the weld metal and the welded joint was equal to that of the base metal. However, the welded joint ruptured in the HAZ softened zone and its ductility ...
A device is described for transporting loads, especially for moving belt driving stations in open pit mining operations with a propelling mechanism which for lifting a respective load is operable to move into a free space formed by the load with the ground. The device comprises a plurality of lifting mechanisms, by means of which, a lifting platform can be brought into engagement with a supporting surface of the load. The device comprises at least one supporting member which is so designed that it prevents the lifting platform from lifting off lifting mechanisms. Furthermore, means are provided which permit a turning of the lifting platform relative to the lifting mechanisms about a vertical axis which is arranged in a certain relationship to the propelling mechanism.
Background, aim, and scope Semi-trailers with load boxes are the most important mode of grain transport by land in the world. Load boxes can be produced with different materials such as: wood, steel, and synthetic material. They are responsible for effectiveness retention and quality of grains during the transport. Among the main aspects to be considered and valued when selecting materials for load boxes are the final mass of the semi-trailer, loss of grains, and mechanical properties. Environmental performance is another important aspect to be taken into account for developing and selecting new materials in this kind of application. This study presents a comparative environmental evaluation of load boxes built from two different materials (a wood panel and a three-layer synthetic (TLS) pa...
Experimental results of quasi-static and dynamic fracture of particle-filled polymer composite (PFPCM) "ALTUGLAS EI CH25" with a matrix of polymethylmethacrylate (PMMA) are reported in this paper. PMMA matrix is filled with rubber particles, as result a shock-resistant transparent composite is produced. The main task was to investigate experimentally and theoretically the fracture toughness of this composite under static and dynamic loading. A high-rate loading has been created by impulse magnetic field. Analysis of fracture process and its relation with the load parameters and material microstructure have been established. Application of the original testing method enabled determination of fracture toughness at very short loading times and comparison of the results with material dynamic p...
This paper introduces the summary of design guideline (draft) for the limit state design method for foundation structures, and examples of calculations on pile foundations. The limit states were set using the load to transformation curves, and the limit state No. 3 in particular assumed a large earthquake, a state that a foundation is fatally damaged because of rarely acting loads that lead to generation of displacement and loss of stability and functions. Ground survey coefficient, ground resistance coefficient, and ground property coefficient were defined especially as the safety coefficients. With respect to the displacement in the limit state No. 3, a restriction value was set for the plasticity of the foundation. Loads were given considerations of combination of permanent load, variation load, and accidental load, each having been set with a ...
Accurately predicting wind turbine blade loads and response is important for the proper design of wind turbines. The need to accurately predict both deterministic and stochastic blade loads is now widely recognized. Previous rotor code development and validation efforts at NREL have concentrated on prediction of deterministic and stochastic blade loads for rigid hub rotors. During the past year this effort was expanded for predicting blade and shaft loads for two-bladed teetering hub rotors. The NREL (formerly SERI) Teetering Rotor Analysis Program (STRAP), a derivative of the Force and Loads Analysis Program (FLAP), can include the effects of rotor undersling, delta-3 and the effects of a concentrated hub mass. The degrees of freedom include rotor teeter and symmetric and asymmetric rotor flap modes. A time-dependent, prescribed yaw motion can also be input to the code. ...
Taiheiyo coal deashed using acid treatment and loaded with potassium or calcium was hydro-cracked under gaseous phase to discuss effects of these metals on liquefaction reaction. In addition, the loaded coal was added with red mud catalyst to examine effects of the addition. The loaded potassium has a softening power, and particularly the potassium adsorbed into surface and micropores in the coal decomposes selectively HI-BS and BI-PS and generates gas and HS. On the other hand, potassium deposited on coal surface promotes direct gas production from the coal. Irrespective of its loading modes, calcium has a catalytic nature to produce HI-BS selectively. Calcium also acts to impede decomposition of HI-BS into HS. Adding red mud catalyst to potassium loaded coal increases the inversion rate and the liquefaction yield, and most of the increase is accounted for by HI -BS, and BI-PS. ...
A distinguishing design feature of CANDU nuclear reactors is the use of horizontal fuel channels housed in a horizontal vessel called a calandria, which is made of stainless steel 304L. Each channel consists of a Zr-2.5%Nb alloy pressure tube and an externally concentric Zr-2 calandria tube. The calandria tubes are joined to the end plates (tubesheets) of the calandria vessel by joints formed by roller expansion. The bores in the tubesheets are grooved. Roller expanded joints provide a cost effective means of joining dissimilar materials, require minimal space and no maintenance. The quality of these roller expanded joints is important from a sealing, strength and stress corrosion point of view. The roller expansion process consists of expanding the calandria tubes to deform them plastically against the bores and into the grooves of the tubesheets. Therefore, understanding the effect of the number, geometry and the pitch of ...
A 25m wind turbine blade was tested to failure when subjected to a flapwise load. With the test setup, it was possible to test the blade to failure at three diffe-rent locations. The objective of these tests is to learn about how a wind turbine blade fails when exposed to a large flapwise load and how failures propagate. The report shows also results from ultra sonic scan of the surface of the blade and it is seen to be very useful for the detection of defects, especially in the layer between the skin laminate and the load carrying main spar. Acoustic emission was successfully used as sensor for the detection of damages in the blade during the test. The report contains measurements of the total deflection of the blade, the local deflection of the skin and the load carrying main spar and also measurement of strain all as a function of the applied load and up to failure of the blade. ...
The solubilities of plutonium and uranium have been determined for alkaline salt solutions having compositions which bound those which will be processed in the In-Tank Precipitation (ITP) process. Loadings of plutonium and uranium onto monosodium titanate (MST) have been determined at temperatures bounding those expected to occur during ITP and using a salt solution which was determined to have the maximum solubility for uranium and plutonium. Fissile loadings increase with decreasing amounts of MST in contact with the salt solutions saturated in plutonium and uranium. At MST concentrations bounding those which are planned for the ITP process, expressions for the maximum loadings (wt %) are determined to be 0.29 - 0.20x[MST] for plutonium and 1.8 - 0.29x[MST] for uranium, where [MST] is the concentration of MST in grams/liter. These expressions are valid over the range of MST concentrations from 0.05 to 0.51 g/L and ...
The thermal contact resistance between balls and inner and outer rings of thermally steady space-use deep groove ball bearings was studied experimentally to verify the validity of the previously proposed calculation method for the resistance. The 440C stainless steel single row bearing was used for measuring its steady state temperature distributions in a vacuum environment under axial, radial and combined load conditions. As a result, the experimental results of the resistance well agreed with calculated ones under each load condition resulting in the sufficient validity at nearly the same surface roughness. It was necessary to apply a static equivalent radial load to calculation under the combined load that a contact angle is larger than the angle of resultant force dependent on both load components. In experiments under only radial load, measurement of outer ...
The objective of the study was to investigate neuronal processing during the encoding, retention and retrieval phases of a serial visual working memory task. Particularly, we were interested in how these phases are affected by working memory load and how processing is modulated by methylphenidate. Healthy adults were asked to memorize the order of four, five or six pictures under methylphenidate (20mg) and under placebo while brain electrical activity was recorded. On the performance level, the number of correct responses decreased with increasing working memory load. Concerning brain electrical activity, in the encoding phase P3 amplitudes increased at midline electrodes with increasing memory load while load had no effect in the retention and retrieval phase. Medication neither influenced performance nor the different processing stages significantly. Our data provide evidence that during the encoding ...
An experimental apparatus has been built that allows direct measurement of the oil film thickness in a bearing that is subjected to dynamic loads and shaft speeds representative of those occurring in automotive engine connecting rod, big-end bearings. Dynamic motion of the shaft, relative to the bearing, is measured as a function of shaft rotational angle, using non-contact, eddy-current probes. A computer based data acquisition system is used to measure, record, and analyze the journal position in the bearing. The test bearing is 63.5 mm in diameter by 25.4 mm long, and is loaded using a servo-hydraulic actuator rated at 98.3 kN. The journal has an operating speed of 500 to 3800 rpm. The actuator is controlled by a computer-generated waveform that can duplicate load profiles developed by various engines operating at a wide range of conditions. Measurements taken with the shaft statically loaded show ...
Varying load can cause changes in a measured gearbox vibration signal. However, conventional techniques for fault diagnosis are based on the assumption that changes in vibration signal are only caused by deterioration of the gearbox. There is a need to develop a technique to provide accurate state indicator of gearbox under fluctuating load conditions. This paper presents an approach to gear fault diagnosis based on complex Morlet continuous wavelet transform under this condition. Gear motion residual signal, which represents the departure of time synchronously averaged signal from the average tooth-meshing vibration, is analyzed as source data due to its lower sensitiveness to the alternating load condition. A fault growth parameter based on the amplitude of wavelet transform is proposed to evaluate gear fault advancement quantitatively. We found that this parameter is insensitive to varying load and ...
This paper presents a systematic approach to the automatic determination of the evolution of the rigid-plastic structural response caused by a proportional or single parameter pressure loading which varies with time in a monotonic non decreasing fashion. The frame structure is envisaged as a network, and the fundamental vectorial conditions characterising its behaviour at any instant of time are combined in a consistent manner. By considering the level of the pressure loading to be a single load parameter ranging monotonically from zero to infinity, the structural governing system may be regarded as a parametric linear complementary problem. (author). 13 refs., 2 figs.
The load-carrying capacity and ultimate deformation capacity of timber-concrete composite systems can be significantly influenced by the ductility of the connection between the two materials. The use of more ductile connections can increase the load-carrying capacity of the composite system as well as its ultimate deformation capacity. In this work, the potential increase that might be expected for these two parameters due to the use of ductile connections will be assessed through numerical simulations, taking the non-linear behaviour of the connections into account. Furthermore, the connection ductility required to achieve the maximum load capacity depends on the mechanical properties of the connection as well as on the geometric and mechanical properties of the composite system. There ar...
ABS>A horizontal steam generator design for the SM-2 was lysis to determine the per formance of such a steam generator under steady state operating conditions and during load transients, The configuration for this design is a two- drum unit consisting of a heat exchanger unit and separator drum interconnected by integral riser and downcomer. An analog computer was used to analyze the steam generator behavior Wring load transients. The effect of various design changes on the response of the steam generator to step chages in load was determined. The horizontal steam generator design was compared to the existing vertical steam generator design for weight, size, price, and performance. (auth)
A study was conducted on diesel engines to find out the effect of induction rate of biogas on engine performance indices. The results of dual fuel engine performance was compared with diesel mode for various levels of biogas induction rate (0.3 to 7.2 l/s) engine load (20% to full load) and injection timing (20.6 to 48 before top dead centre). At full and 80% brake load, the best energy mix between diesel and biogas was 1.5:1 and 4:1 respectively. (author). 7 refs., 7 figs., 4 tabs.
Long crack fatigue threshold ({delta} K{sub th}) and crack closure behaviour of two thermomechanically processed microalloyed (MA) ferrite-pearlite steels are reported. {delta} K{sub th} and crack closure were measured using a dynamic compliance measurement technique. Crack closure was observed at low load ratios (R < 0.5) and the fatigue thresholds decreased with increasing load ratio. In both steels, the closure-free intrinsic threshold ({delta} K{sub eff} {sub th}) was found to be independent of the load ratio. (orig.)
Several types of X-band high power loads developed for several tens of MW range were designed, fabricated and used for high power tests at X-band facility of KEK. Some of them have been used for many years and few units showed possible deterioration of RF performance. Recently revised-design loads were made by CERN and the high power evaluation was performed at KEK. In this paper, the main requirements are recalled, together with the design features. The high power test results are analysed and presented
The effect of additives on the grafting of a monomer, butylmethacrylate (BA), into simul (a soft wood) has been studied using {sup 60}Co source at 3 Mrad. The enhancement of polymer loading (grafting) by the addition of minute amounts (1%) of oligomers and of polyfunctional monomers into simul + BA system has been further increased in the presence of acid and urea. The synergistic polymer loading yields by acid addition cause substantial decrease of tensile strength values of wood-plastic composite; but urea increases both polymer loading and tensile strength values synergistically in these systems. (author).
The effect of additives on the grafting of a monomer, butylmethacrylate (BA), into simul (a soft wood) has been studied using "6"0Co source at 3 Mrad. The enhancement of polymer loading (grafting) by the addition of minute amounts (1%) of oligomers and of polyfunctional monomers into simul + BA system has been further increased in the presence of acid and urea. The synergistic polymer loading yields by acid addition cause substantial decrease of tensile strength values of wood-plastic composite; but urea increases both polymer loading and tensile strength values synergistically in these systems. (author).
An aspiration cover is proposed for the site of loading a belt conveyer including a housing arranged above the belt conveyer in whose cover there is an aspiration sleeve and a discharge chute from the upper wall and a guide having a cushioning plate on the lower end. It is distinguished by the fact that in order to improve the effectiveness of removing dust by decreasing the volume of aspirated air, the cover between the aspiration sleeve and the upper wall of the loading chute is convex in the inside of the housing and has a smooth connection to the upper wall of the discharge chute turned towards the cushioning plate.
The non linear electrical loads can give rise to a number of disturbances in electrical power networks. Among them, the high consumption of relative power is to be noted and so is the several harmonic components which may be injected in the industry system and very often in the utility system. So, by using appropriate technical considerations, as well as measurements in typical special electrical loads, such negative effects are analyzed and ways of minimizing them are suggested. (author) 3 refs., 11 figs., 6 tabs.
The problem of pile groups subjected to lateral loads is of interest particularly in offshore and coastal regions. An understanding of pile-soil interaction is essential in designing such pile foundations. In this paper, a simplified finite element analysis in conjunction with Yegian and Wright approach has been presented to study the behavior of pile groups under lateral loads. The pile is treated as a shear beam and the soil media is assumed to be linear elastic. The results of the analysis are used to estimate: (1) Lateral Group Efficiency and (2) Extent of stress influence around the pile. The results obtained from the theoretical predictions are found to be reasonably in good agreement with the published literature.
Heat fusion is the most common joining method for polyethylene gas distribution piping. Butt fusion was studied with the intent of relating the quality of the joint to the joining conditions. A semi-empirical approach was used. The thermofluid consequences of joining conditions such as heater temperature, heating time and joining parameter were calculated using a computer model. The model was validated by instrumented tests. The strength of the joints was gauged by destructive mechanical testing. Tensile and tensile impact tests were used. Over 150 joints were fabricated using four different polyethylene resins. Most of the data are given in GRI Report No. 88/0276.2 -- Volume 2: Technical Reference on Butt Heat Fusion Joining of Polyethylene Gas Pipes. A parameter, termed the Joining Parameter, was found to characterize the joining conditions. Of the mechanical tests parameters, the impact energy was found to have the best ...
The effect of accelerated thermal cycling on a joint between modified 9Cr-1Mo steel (Grade 91) and Alloy 800 welded with Inconel 82 and 182 filler material is discussed. This is part of a trimetallic transition joint involving Grade 91-Alloy 800-316LN austenitic stainless steel for steam generator application. It has been shown that, during thermal cycling following the typical post-weld tempering treatment at 760 deg. C for 2 h, no carbon diffusion occurs from the ferritic steel towards the weld metal. There is, in fact, a hardness increase at the ferritic steel/weld metal interface which is probably a result of work hardening. Carbon migration sets in only after unusually long post-weld heat treatments for 20 and 50 h at 760 deg. C followed by thermal cycling. Significantly, even under the most severe thermal cycling test conditions imposed, no cracking or oxide notching could be detected, thus demonstrating the superior performance potential ...
Heat fusion is the most common joining method for polyethylene gas distribution piping. Butt fusion was studied with the intent of relating the quality of the joint to the joining conditions. A semi-empirical approach was used. The thermofluid consequences of joining conditions such as heater temperature, heating time and joining parameter were calculated using a computer model. The model was validated by instrumented tests. The strength of the joints was gauged by destructive mechanical testing. Tensile and tensile impact tests were used. Over 150 joints were fabricated using four different polyethylene resins. Most of the data are given in GRI Report No. 88/0276.2 -- Volume 2: Technical Reference on Butt Heat Fusion Joining of Polyethylene Gas Pipes. A parameter, termed the Joining Parameter, was found to characterize the joining conditions. Of the mechanical tests parameters, the impact energy was found to have the best ...
We report on the spectral cross-calibration results of the Konus-Wind, the Suzaku/WAM, and the Swift/BAT instruments using simultaneously observed gamma-ray bursts (GRBs). This is the first attempt to use simultaneously observed GRBs as a spectral calibration source to understand systematic problems among the instruments. Based on these joint spectral fits, we find that 1) although a constant factor (a normalization factor) agrees within 20% among the instruments, the BAT constant factor shows a systematically smaller value by 10-20% compared to that of Konus-Wind, 2) there is a systematic trend that the low-energy photon index becomes steeper by 0.1-0.2 and Epeak becomes systematically higher by 10-20% when including the BAT data in the joint fits, and 3) the high-energy photon index agrees within 0.2 among the instruments. Our results show that cross-calibration based on joint spectral analysis is an important step to ...
Quantitative assessment of bone scintigraphy was performed in fifty-six patients with hip joint disease including femoral neck fracture, aseptic necrosis of the femoral head, traumatic dislocation of the hip, Perthes disease, and transient synovitis of the hip. In the static study, bone scintigraphy was obtained 3 hours after injection of sup(99m)Tc-MDP by gamma camera equipped with a computer and uptake ratios were calculated. In the dynamic study, bone scintigraphy was performed in one, 3 and 5 hours after injection of radionuclide. Femoral head uptake ratio was markedly decreased in osteonecrosis following femoral neck fracture and characteristically increased in aseptic necrosis of the femoral head but prolonged retention of sup(99m)Tc-MDP could be observed. Uptake ratios of epiphysis were decreased in Perthes disease but normal in transient synovitis of the hip. Static and dynamic study of bone scintigraphy may be useful for early diagnosis and treatment in ...
Accomplishments for the quarter are presented for the following areas of research: oil shale, tar sand, coal, advanced exploratory process technology, and jointly sponsored research. Oil shale research includes; oil shale process studies, environmental base studies for oil shale, and miscellaneous basic concept studies. Tar sand research covers process development. Coal research includes; underground coal gasification, coal combustion, integrated coal processing concepts, and solid waste management. Advanced exploratory process technology includes; advanced process concepts, advanced mitigation concepts, and oil and gas technology. Jointly sponsored research includes: organic and inorganic hazardous waste stabilization; development and validation of a standard test method for sequential batch extraction fluid; operation and evaluation of the CO[sub 2] HUFF-N-PUFF Process; fly ash binder for unsurfaced road aggregates; solid state NMR analysis ...
The extraction of cosmological parameters from microwave background observations relies on specific assumptions about the statistical properties of the data, in particular that the p-point distributions of temperature fluctuations are jointly-normal. Using a battery of statistical tests, we assess the multivariate Gaussian nature of the Wilkinson Microwave Anisotropy Probe (WMAP) 1st year data. The statistics we use fall into three classes which test different aspects of joint-normality: the first set assess the normality of marginal (one-point) distributions using familiar univariate methods; the second involves statistics that directly assess joint-normality; and the third explores the evidence of non-linearity in the relationship between variates. We applied these tests to frequency maps, `foreground-cleaned' assembly maps and all-sky CMB-only maps. The assembly maps are of particular interest as when combined with the ...
Microstructural evolution due to thermal effects was studied in micro solder joints (55 {+-} 5 {micro}m). The composition of the Sn/Pb solder studied was found to be hypereutectic with a tin content of 65--70 wt%.This was determined by Energy Dispersive X-ray analysis and confirmed with quantitative stereology. The quantitative stereological value of the surface-to-volume ratio was used to characterize and compare the coarsening during thermal cycling from 0--160 C to the coarsening during annealing at 160 C. The initial coarsening of the annealed samples was more rapid than the cycled samples, but tapered off as time to the one-half as expected. Because the substrates to which the solder was bonded have different thermal expansion coefficients, the cycled samples experienced a mechanical strain with thermal cycling. The low-strain cycled samples had a 2.8% strain imposed on the solder and failed by 1,000 cycles, despite undergoing less coarsening than the annealed ...
Understanding the influence of interfacial structures on the nanoarchitecture mechanical properties is of particular importance for its mechanical applications. Due to a small size of constituting nanostructural units and a consequently high volume ratio of such interfacial regions, this question becomes crucial for the overall mechanical performance. Boron nitride bamboo-like nanotubes, called hereafter boron nitride nanobamboos (BNNBs), are composed of short BN nanotubular segments with specific interfaces at the bamboo-shaped joints. In this work, the mechanical properties of such structures are investigated by using direct in situ transmission electron microscopy tensile tests and molecular dynamics simulations. The mechanical properties and deformation behaviors are correlated with the interfacial structure under atomic resolution, and a geometry strengthening effect is clearly demonstrated. Due to the interlocked joint interfacial ...
Despite their high medical relevance, the principles of lubrication in natural joints are still unclear. It is generally accepted, that the presence of hyaluronic acid (HA), the main component of the synovial liquid, plays an important role for the low friction observed. Furthermore, it is assumed that surface active lipids participate in the lubrication. Using a model system of lipid bilayers deposited on a polyelectrolyte (PE) cushion and in contact with HA solution, we started to investigate the effects of pressure and shear forces, as experienced by natural joints, on the internal structure of the SiO{sub 2}/PE/lipid/HA interface and the bulk HA solution by neutron reflectometry (NR), complemented by in situ ellipsometry and quartz crystal microbalance (QCM-D) measurements. Only on positively charged polyelectrolyte surfaces, the successful build-up of the model system could be demonstrated. By NR, the existence of an irreversibly absorbed, ...
This paper proposes a new pattern recognition system employing optical joint transform correlation (JTC) technique which offers a great number of advantages over similar digital techniques, including very fast operation, simple architecture and capability of updating the reference image in real time. The proposed JTC technique incorporates a synthetic discriminant function (SDF) of the target image estimated from different training images to make the pattern recognition performance invariant to noise and distortion. It then involves four different phase-shifted versions of the same target SDF reference image, which are individually joint transform correlated with the given input scene. When the correlation signals are combined, it produces a single cross-correlation peak corresponding to each potential target present in the given input scene. The proposed technique also includes a fringe-adjusted filter to generate a delta-like correlation peak ...
In 576 patients quantitative scintigraphy of the sacroiliac joints and the spinal cord with "9"9"mTc-pyrophosphate was performed. 328 were patients with proven ankylosing spondylitis according to the New York criteria. 120 were patients with a clinically and roentgenologically suspected ankylosing spondylitis and 128 persons formed a healthy control group. The count rate in small regions of interest (ROI) in the sacroiliac joints, the spinal cord and the os sacrum were compared on the basis of indexes. The scintigraphic data of patients with ankylosing spondylitis were compared with the healthy control group and with the radiographic findings and radiologic staging of the disease. In a longitudinal follow-up study during 1 to 6 years these investigations were continued together with clinical and roentgenological checks. Quantitative bone scintigraphy provides characteristic indexes for ankylosing spondylitis, indicating the increased mineral ...
In 620 patients quantitative bone scintigraphy with "9"9"mTc pyrophosphate of the sacroiliac joints and of the spine was performed: 365 patients with confirmed ankylosing spondylitis, 125 patients with clinical radiological suspicion for ankylosing spondylitis (probable Bechterev) and control group of 130 healthy individuals. By comparison of the activity in zones of interest of the sacroiliac joints, the spine and sacrum, the following indices were determined: sacroiliac (separately for the left and right sacroiliac joints), index D_1_0/sacrum, index L_4/sacrum and index C_7/sacrum. The scintigraphic finding was compared to the X-ray one and to the radiological stage of the disease. A long-term follow-up of the patients was carried out during 1-6 years with scintigraphic, X-ray and clinical investigations. Emphasis was laid upon the posibilities for quantitative scintigraphy for early diagnostics of ankylosing spondylitis. ...
The clinical courses of heterotopic ossification (HO) as a consequence of trauma and central nervous system insults have many similarities as well as dissimilarities. Detection is commonly noted at two months. The incidence of clinically significant HO is 10%-20%. Approximately 10% of the HO is massive and causes severe restriction in joint motion or ankylosis. The most common sign and symptom are decreased range of motion and pain. The locations are the proximal limbs and joints. Sites of HO about a joint may vary according to the etiology of the HO. Roentgenographic evolution of HO occurs during a six-month period in the majority of patients. Treatment modalities include diphosphonates, indomethacin, radiation, range of motion exercises, and surgical excision. Surgical timing differs according to etiology: traumatic HO may be resected at six months; spinal cord injury HO is excised at one year; and traumatic brain injury ...
The clinical courses of heterotopic ossification (HO) as a consequence of trauma and central nervous system insults have many similarities as well as dissimilarities. Detection is commonly noted at two months. The incidence of clinically significant HO is 10%-20%. Approximately 10% of the HO is massive and causes severe restriction in joint motion or ankylosis. The most common sign and symptom are decreased range of motion and pain. The locations are the proximal limbs and joints. Sites of HO about a joint may vary according to the etiology of the HO. Roentgenographic evolution of HO occurs during a six-month period in the majority of patients. Treatment modalities include diphosphonates, indomethacin, radiation, range of motion exercises, and surgical excision. Surgical timing differs according to etiology: traumatic HO may be resected at six months; spinal cord injury HO is excised at one year; and traumatic brain injury ...
In this work, a mixed cationic--anionic [i.e. cetyltrimethylammonium bromide-sodium octyl sulphate] surfactant system was used to synthesize the magnetite particles. The loading content of iron ions (Fe{sup 3+} and Fe{sup 2+}) into the surfactant system was varied to study its effect on the formation of magnetite, magnetic and morphological properties of the magnetite particles encapsulated by the surfactant vesicles. It has been verified that the vesicle-encapsulated magnetite particles with sizes from 100 to 200 nm were formed, which were almost independent of the loading content of iron ions. However, the morphological structure of the magnetite particles was dependent on the loading content of iron ions and there existed an optimal loading content for a full packing of the surfactant vesicles with the magnetite particles.
In this work, a mixed cationic--anionic [i.e. cetyltrimethylammonium bromide-sodium octyl sulphate] surfactant system was used to synthesize the magnetite particles. The loading content of iron ions (Fe"3"+ and Fe"2"+) into the surfactant system was varied to study its effect on the formation of magnetite, magnetic and morphological properties of the magnetite particles encapsulated by the surfactant vesicles. It has been verified that the vesicle-encapsulated magnetite particles with sizes from 100 to 200 nm were formed, which were almost independent of the loading content of iron ions. However, the morphological structure of the magnetite particles was dependent on the loading content of iron ions and there existed an optimal loading content for a full packing of the surfactant vesicles with the magnetite particles.
This paper presents a detailed characterization and rheometric property study of in-situ sodium activated, organomodified bentonite clay - styrene-butadiene rubber (SBR) nanocomposite. It was found that around 10phr loading was the optimum level for maximum effect of the organo clay. The WAXD data indicated that at higher loading there was formation of agglomerations in the matrix. It was found that organo clay compound exhibited lower maximum torque in comparison to equivalent amount of carbon black loaded compound. The nanocomposites were also used for partial replacement of N330 carbon black in a highly black loaded compound. Part replacement of the carbon black with nano-clay reduced the maximum rheometric torque in comparison to the control compound. Detail study revealed that with sl...
Wood-polymer composites (WPC) have been prepared of pinewood with different monomers using Gamma radiation: acrylamide, butyl acrylate, butyl methacrylate, styrene, acrylonitrile, and polyester. The polymer loading was determined as a function of monomer concentration and absorbed dose. The data show that polymer loading increases by increasing the monomer concentration. In two cases, BMA and polyester, the polymer loading decreases at high concentrations. This can be explained by the increase of the viscosity. Thus the diffusion of the compound into bulk would be slower. The absorbed dose seems to play a positive role in enhancing the polymer loading by increasing the dose. The mechanical properties, tensile and compression strength, have been improved in the most cases for all monomer concentrations or absorbed doses. Using polyester there was no improvement in the mechanical properties, and using ...
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...
A method for determining the rational capacity of the shield supports under various geological conditions is proposed. Based on the instrumentation of the pressure histories of the shield legs in eight mines, the relation between the final load or the increment of support resistance in a mining cycle and the setting load is established. The relation is represented by a mathematical equation with characteristic constants. Those constants are related to the physical properties of the immediate and main roof strata. Nomographs were constructed for determining the constants under various geological conditions. The paper discusses the principles and step-by-step procedures for determining the rational setting and yield loads for all the shield supports employed in the eight mines. The predicted values are then compared with the actual ones used by the operators. 7 refs., 6 figs., 4 tabs.
This paper describes Automatic Refueling Planning System (ARPS) for a nuclear power station using Genetic Algorithms (GA) and a Simulated Annealing (SA). ARPS has been developed and verified by applying to the Fugen nuclear power station (NPS), which is a 165MWe, heavy water-moderated, boiling light water-cooled, pressure tube-type reactor developed by JNC utilizing mainly uranium and plutonium mixed oxide (MOX) fuel. Fuel loading patterns have been managed independently in the Fugen NPS since the initial core. A planning of an adequate fuel loading pattern on each operational cycle needs one to two months even for expert core management engineers, for the reason that it has multi-objective optimization and nonlinear problems. In order to achieve the optimum fuel loading pattern and a fuel cost reduction, ARPS has been developed by JNC and CRC Solutions Corporation for the last five years. ARPS firstly generates several ...
The load-following operation of nuclear power plants will become inevitable due to the increased nuclear share in the total electricity generation. As a groundwork for the load-following capability of the Korean next generation PWRs, the state-of-the-art has been reviewed. The core control principles and methods are the main subject in this review as well as the impact of load-following operations on the fuel performance and on the mechanical integrity of components. To begin with, it was described what the load-following operation is and in what view point the technology should be reviewed. Afterwards the load-following method, performance and problems in domestic 900 MWe class PWRs were discussed, and domestic R and D works were summarized. Foreign technologies were also reviewed. They include Mode G and Mode X of Foratom, D and L bank method of KWU, the method using PSCEA of ...
High-energy synchrotron x-ray diffraction (XRD) has been used to quantify load transfer in bovine plexiform bone. By using both wide-angle and small-angle XRD, strains in the mineral as well as the collagen phase of bone were measured as a function of applied compressive stress. We suggest that a greater proportion of the load is borne by the more mineralized woven bone than the lamellar bone as the applied stress increases. With a further increase in stress, load is shed back to the lamellar regions until macroscopic failure occurs. The reported data fit well with reported mechanisms of microdamage accumulation in bovine plexiform bone.
0pen ended piles develop internal frictional resistance between the internal soil plug end the pile wall during axial loading. Current pipe pile design practice assumes that the ultimate internal skin friction is of the same order of magnitude as the outer skin friction. This paper describes a series of laboratory pile load tests on instrumented model pipe piles, designed to investigate the development of plug stresses and skin friction along the plug length during pile loading. The piles contain sand columns of various relative densities and of different heights. The soil plugs are loaded to failure under fully drained conditions. The test data indicate that internal skin friction in sand can be substantially higher than assumed in conventional design practice. This finding could lead to significant economical savings on future pipe pile foundations in sand.
The fatigue and fracture behavior of hard tissues are topics of considerable interest today. This special group of organic materials comprises the highly mineralized and load-bearing tissues...Full Text Available
The nucleation of microdamage under dynamic loading was investigated through planar impact experiments accomplished with a light gas gun. The microscopic observation of recovered and sectioned specimens showed that microcracks were nucleated only by cracking of brittle particles inside material. However, for comparison the in situ static tensile tests on the same material conducted with a scanning electron microscope showed that the microcracks were nucleated by many forms those were fracture of ductile matrix, debonding particles from matrix and cracking of brittle particles. The quantitative metallographic observations of the specimens subjected to impact loading showed that most of the cracked particles were situated on grain boundaries of the aluminum matrix. These facts suggested the concept of critical size and incubation time of submicroscopic cavities in the dynamic case and the mechanism of embryo-damage induced nucleation by fracture ...
Heat transfer through the gas diffusion layer (GDL) is a key process in the design and operation of a PEM fuel cell. The analysis of this process requires the determination of the effective thermal conductivity as well as the thermal contact resistance between the GDL and adjacent surfaces/layers. The Part 1 companion paper describes an experimental procedure and a test bed devised to allow separation of the effective thermal conductivity and thermal contact resistance, and presents measurements under a range of static compressive loads. In practice, during operation of a fuel cell stack, the compressive load on the GDL changes. In the present study, experiments are performed on Toray carbon papers with 78% porosity and 5% PTFE under a cyclic compressive load. Results show a significant hy...
... In fact, for dynamic loading, the ultimate compressive strength can be more than doubled (Bischoff and Perry 1991), whereas the ultimate uniaxial ...
;Table of Contents: Legal authority; Summary of proposed regulations; Industry definition and waste streams; Industry description; Data and information gathering; Selection of pollutant parameters; Drilling wastes-characterization, control, and treatment technologies; Produced water-characterization, control, and treatment technologies; Miscellaneous waste-characterization, control, and treatment technologies; Cost and pollutant loading determination of drilling fluids and drill cuttings; Compliance cost and pollutant load determination of produced water; Compliance cost and pollutant load determination of well treatment, workover, and completion fluids; Cost and pollutant loading determination of deck drainage; Options selection-rationale and total costs; Pretreatment standards; Non-water quality environmental impacts and other factors; Best Management Practices; and Appendices.
Background Photopolymerizable poly(ethylene glycol) (PEG) hydrogels offer a platform to deliver cells in vivo and support three-dimensional cell culture but should be designed to degrade in sync with neotissue development and endure the physiologic environment. Questions/purposes We asked whether (1) incorporation of degradation into PEG hydrogels facilitates tissue development comprised of essential cartilage macromolecules; (2) with early loading before pericellular matrix formation, the duration of load affects matrix production; and (3) dynamic loading in general influences macroscopic tissue development. Methods Primary bovine chondrocytes were encapsulated in hydrogels (n?=?3 for each condition). The independent variables were hydrogel degradation (nondegrading PEG and degrading olig...
... being designed for projected Minotaur IV launch load environments, with design objectives of light weight, integrated vibration isolation, low shock ...
Varying load can cause changes in a measured gearbox vibration signal. However, conventional techniques for fault diagnosis are based on the assumption that changes in vibration signal are only caused by deterioration of the gearbox. There is a need to develop a technique to provide accurate state indicator of gearbox under fluctuating load conditions. This paper presents an approach to gear fault diagnosis based on complex Morlet continuous wavelet transform under this condition. Gear motion residual signal, which represents the departure of time synchronously averaged signal from the average tooth-meshing vibration, is analyzed as source data due to its lower sensitiveness to the alternating load condition. A fault growth parameter based on the amplitude of wavelet transform is proposed ...
This paper presents a design of fuzzy power system stabilizer (FPSS) using adaptive evolutionary computation (AEC). We have proposed an adaptive evolutionary algorithm which uses a genetic algorithm (GA) and an evolution strategy (ES) in an adaptive manner in order to take merits of two different evolutionary computations. FPSS shows better control performances than conventional power system stabilizer (CPSS) in three-phase fault with heavy load which is used when tuning FPSS. To show there robustness of the proposed FPSS, it is applied to damp the low frequency oscillations caused by disturbances such as three-phase fault with normal and light load, the angle deviation of generator with normal and light load and the angle deviation of generator with heavy load. Proposed FPSS shows better robustness than CPSS. (author). 15 refs., 13 figs., 3 tabs.
Los Alamos National Laboratory (LANL) and the University of California, San Diego (UCSD) have taken the unprecedented step of creating a collaborative, multi-disciplinary graduate education program and associated research agenda called the Engineering Institute. The mission of the Engineering Institute is to develop a comprehensive approach for conducting LANL mission-driven, multidisciplinary engineering research and to improve recruiting, revitalization, and retention of the current and future staff necessary to support the LANL' s national security responsibilities. The components of the Engineering Institute are (1) a joint LANL/UCSD degree program, (2) joint LANL/UCSD research projects, (3) the Los Alamos Dynamic Summer School, (4) an annual workshop, and (5) industry short courses. This program is a possible model for future industry/government interactions with university partners.
Larsen syndrome is an autosomal-dominant disorder characterized by multiple joint dislocations, vertebral anomalies and dysmorphic facies. Both autosomal-dominant and autosomal-recessive forms of the disorder have been proposed. Individuals with autosomal-dominant Larsen syndrome have characteristic ''cylindrical-shape'' thumbs caused by broad, shortened phalanges. Autosomal-dominant Larsen syndrome results from heterozygosity for mutations in filamin B, a cytoskeletal protein involved in multicellular processes. We report here a patient with a duplicated or accessory distal thumb phalanx and multiple large joint dislocations who was shown to be heterozygous for a filamin B mutation predicting the amino acid substitution G1691S. This adds a new radiographic finding, duplicated or accessory distal phalanx, to the radiographic abnormalities seen in this rare dominant disorder. (orig.)
A novel adhesive for carbon materials composed of phenol-formaldehyde resin, boron carbide and fumed silica, was prepared. The adhesive property of graphite joints bonded by the above adhesive treated at high-temperatures was tested. Results showed that the adhesive was found to have outstanding high-temperature bonding properties for graphite. The adhesive structure was dense and uniform even after the graphite joints were heat-treated at 1500 deg. C. Bonding strength was 17.1 MPa. The evolution of adhesive structure was investigated. The results indicated that the addition of the secondary additive, fumed silica, improved the bonding performance greatly. Borosilicate phase with better stability was formed during the heat-treatment process, and the volume shrinkage was restrained effectively, which was responsible for the satisfactory high-temperature bonding performance of graphite.
Polyethylene (UHMWPE) wear in current knee prosthesis causes prosthesis loosening after no more than 15 years. In this work, a steady state one-dimensional lubrication model with non- Newtonian fluid, porous elastic layer on tibial component, ultra-filtration mechanism of fluid and some features of the surface roughness is studied through a numerical technique based on the Finite Element Method. The results show that the UHMWPE stiffness makes difficult the lubrication mechanism of the artificial joint and promotes abrasive and fatigue wear. Nevertheless, the use of compliant porous materials on the tibial component could reduce friction and wear. Moreover, the ultra-filtration mechanism promotes efficiency on the joint.
Cache locking technique is often utilized to guarantee a tighter prediction of Worst-Case Execution Time (WCET) which is one of the most important performance metrics for embedded systems. However, in Multi-Processor Systems-on-Chip (MPSoC) systems with multi-tasks, Level 2 (L2) cache is often shared among different tasks and cores, which leads to extended unpredictability of cache. Task assignment has inherent relevancy for cache behavior, while cache behavior also affects the efficiency of task assignment. Task assignment and cache behavior have dramatic influences on the overall WCET of MPSoC. This paper proposes joint task assignment and cache partitioning techniques to minimize the overall WCET for MPSoC systems. Cache locking is applied to each task to guarantee a precise WCET. We pr...
The EU-home team is in charge of the R and D related to the ITER baffle first wall. Five small-scale mock-ups, using Be, CFC and W tiles and different armour/heat-sink material joints under development, have been fabricated and thermomechanically tested in FE200 (Le Creusot) and JUDITH (Juelich) electron beam facilities. The small-scale mock-ups have been submitted to thermo-mechanical fatigue tests (up to failure using accelerating techniques). The objective was to determine the performances of the armour material joints under high heat flux cycles. (orig.)
This operation plan covers the period of operations from the time major elements of the joint task force are deployed in the forward area until the completion of on-site operations. It was published for planning purposes only, always subject to periodic revision and refinement as more detailed information became available. ENIWETOK-BIKINI Danger Area, as the term is used in this plan, is that area encompassing ENIWETOK and BIKINI ATOLLS and bounded by the meridians 160 deg 35' - 166 deg 16' east longitude, and by the parallels 10 deg 15' - 12 deg 45' north latitude (an area of 150 by 350 miles).
Competitive bidding for ancillary services (A/S), in addition to bidding for energy, is increasingly recognized as an important part of electricity markets. In this paper, an LP-based approach is presented for solving the multi-product (i.e. energy and A/S products), multi-zone/area physical market dispatch problem. The approach can explicitly represent various constraints, such as reserve requirement constraints, network security limits, and sharing of constrained resource capacity (e.g. maximum unit generation) between energy and reserve. The joint dispatch method, which dispatches energy and reserve market concurrently, is extended to allow inter-zonal reserve trading in multi-zone competitive pool. Numerical examples are included to demonstrate the salient characteristics of the joint dispatch solution.
Young rats were given a single irradiation dose (0.5, 2, 5 or 8 Gy) to the left knee-joint. The right unexposed knee-joint served as control. The animals were decapitated 1.5, 3, 7, 14 or 30 days after the irradiation. Longitudinal bone growth in the tibial epiphysis was established using tetracycline as an intravital marker. During the first 1.5 days after irradiation with 5 and 8 Gy, the growth was slightly inhibited (6-7%). Maximum growth retardation (20%) was found 7 to 14 days after irradiation with 5 and 8 Gy. No consistent effect occurred after 0.5 and 2 Gy. Between 14 to 30 days following irradiation growth was normalized.
Summary The steadily growing epidemic of diabetes mellitus poses a threat for global tuberculosis (TB) control. Previous studies have identified an important association between diabetes mellitus and TB. However, these studies have limitations: very few were carried out in low-income countries, with none in Africa, raising uncertainty about the strength of the diabetes mellitus-TB association in these settings, and many critical questions remain unanswered. An expert meeting was held in November 2009 to discuss where there was sufficient evidence to make firm recommendations about joint management of both diseases, to address research gaps and to develop a research agenda. Ten key research questions were identified, of which 4 were selected as high priority: (i) whether, when and how to sc...
The alloy type 'alloy 800' with its different variants is used for numerous components in high-temperature reactor (HTR) plants, e.g. for hot-gas conductors, the high-pressure part of steam generators, superheaters, steam collecting vessels and live steam conductors. This study deals with the evaluation of creep rupture tests on 28 welded joints of alloy 800 with an accumulated test duration of 410 years, with the objective to obtain quantitative information on a possible loss of strength in comparison with the unwelded material. The longest test period of an individual test amounted to 98,000 h and the analyzed test temperature range lay between 550"0 and 1000"0C. (orig./MM).
Mechanical testing of controlled-purity Ni-xCr-9Fe-yC alloys at 360 C revealed an environmental enhancement in IG cracking and time-dependent deformation in high purity and primary water over that exhibited in argon. Dimples on the IG facets indicate a creep void nucleation and growth failure mode. IG cracking was primarily located at the interior of the specimen and not necessarily linked to direct contact with the environment. Controlled potential CERT experiments showed increases in IG cracking as the applied potential decreased, suggesting that hydrogen is detrimental to the mechanical properties. It is proposed that the environment, through the presence of hydrogen, enhances IG cracking by enhancing the matrix dislocation mobility. This is based on observations that dislocation-controlled creep controls the IG cracking of controlled-purity Ni-xCr-9Fe-yC in argon at 360 C and grain boundary cavitation and sliding results that show the environmental enhancement ...
The swelling behavior which results from simulated fusion environment irradiation of Fe-10% Cr has been characterized with transmission electron microscopy. Specimens were bombarded at 850 K with: a ''triple-beam'' of He"+, D_2"+, and 4 MeV Fe"+"+ ions to 0.3, 1, 3, 10, 30, and 100 dpa (displacement per atom); a ''dual-beam'' of He"+ and 4 MeV Fe"+"+ ions to 30 and 100 dpa; and a ''single-beam'' of 4 MeV Fe"+"+ ions to 30 dpa. The helium and hydrogen injection rates were approx. =10 appm He/dpa and approx. =40 appm D/dpa. Cavities were observed for damage levels of 3 dpa and greater. The swelling was <0.1% for damage levels <30 dpa, but at 100 dpa, there was an increase in the swelling to 2.5% for the ''triple-beam'' irradiation and 1.2% for the ''dual-beam'' irradiation. The swelling rates between 30 and 100 dpa correlate well with calculated values assuming a steady-state swelling-rate regime has been reached. Calculations show the rapid cavity growth associated with this ...
This report covers the technical effort through February, 1989. This effort was directed towards the technology associated with the development of a large scale, long pulse DF-CO{sub 2} chemical laser. Optics damage studies performed under Task 1 assessed damage thresholds for diamond-turned salt windows. Task 2 is a multi-faceted task involving the use of PHOCL-50 for laser gain measurements, LTI experiments, and detector testing by LANL personnel. To support these latter tests, PHOCL-50 was upgraded with Boeing funding to incorporate a full aperture outcoupler that increased its energy output by over a factor of 3, to a full kilojoule. The PHOCL-50 carbon block calorimeter was also recalibrated and compared with the LANL Scientech meter. Cloud clearing studies under Task 3 initially concentrated on delivering a Boeing built Cloud Simulation Facility to LANL, and currently involves design of a Cold Cloud Simulation Facility. A Boeing IRAD funded theoretical study ...
In order to obtain highly reliable InGaP/InGaAlP inner stripe (IS) lasers, the authors have clarified the relation between the maximum CW operation temperature and other laser characteristics, such as the pulsed threshold current, characteristic temperature, series resistance, and thermal resistance. The Al composition of the cladding layer, the carrier concentration of the p-cladding layer, and the thicknesses of the active layer and cladding layer have been optimized. It was found that an Al composition of 0.7 was the most suitable for the cladding layer, and the optimized carrier concentration was 4 x 10/sup 17/ cm/sup -3/. A maximum temperature of 90/sup 0/C was obtained for a 0.1 /mu/m active layer thickness and a 0.6 /mu/m cladding layer thickness. This is the highest value for InGaP/InGaAlP IS lasers, to our knowledge. In the case of a 0.06 /mu/m active layer thickness and a 0.8 /mu/m cladding layer thickness, a maximum temperature of 75/sup 0/C was obtained. IS lasers with ...
A massively-parallel ab initio computer code, which uses Gaussian bases, pseudopotentials, and the local density approximation, permits the study of transition-metal systems with literally hundreds of atoms. We present total energies and relaxed geometries for Ru, Pd, and Ag clusters with N = 55, 135, and 140 atoms; we also used the DMOL code to study 13-atom Pd and Cu clusters, with and without hydrogen. The N = 55 and 135 clusters were chosen because of simultaneous cubo-octahedral (fcc) and icosahedral (icos) sub-shell closings, and we find icos geometries are preferred. Remarkably large compressions of the central atoms are observed for the icos structures (up to 6% compared with bulk interatomic spacings), while small core compressions ({approx} 1 %) are found for the fcc geometry. In contrast, large surface compressive relaxations are found for the fcc clusters ({approx} 2-3% in average nearest neighbor spacing), while the icos surface displays small compressions ({approx} 1%). ...
Treatment chemicals are used in all facets of the natural gas industry (NGI) from well development through transmission and storage of natural gas. The multitude of chemicals used, combined with the dozens of chemical manufacturers and/or suppliers has lead to the availability of hundreds of possible chemical products. Because of the widespread use of chemical products and their numerous sources, the NGI needs access to consistent data regarding their effectiveness and potential environmental impacts. The objective of this work was to evaluate the effectiveness and potential environmental impacts of, chemical products used in the NGI. This assessment was initially focused on biocides and corrosion inhibitors and their use in the gas production, storage and transmission facilities, The overall approach was obtain the necessary data on chemical use and effectiveness directly from the oil and gas industry, supplemented with data/information obtained from the published ...
may be possible to meet those loads with renewable energy systems &mdashachieving zero-net- energy performance.Solar-thermal heating systems, ...p/p Spencer and others argue that renewable energy systems should be considered only after the building envelope ...energy loads are brought low enough, however, a renewable energy system may make sense financially. p
The experimental superconducting magnetic system of 0.5 MJ energy storage is described. The step variation of the winding inductance provides a control by the discharge current at the energy output on a high-ohmic load. The voltage on a load is 45 kV at the current 1100 A under the controllable discharge conditions. The energy transfer coefficient constitutes 0,76 under the maximum-to-minimal current ratio equal to 1.3. 7 refs., 3 figs., 2 tabs.
Wood/polymer composites (WPC) have been prepared from pinewood with different compounds using gamma irradiation: butyl acrylate, butyl methacrylate, styrene, acrylamide, acrylonitrile, and unsaturated polyester styrene resin. The polymer loading was determined with respect to the compound concentration and the irradiation dose. The polymer loading increases generally with increase in the monomer or polymer concentration. Tensile and compression strength have been improved in the four cases, but no improvement was observed using unsaturated polyester styrene resin or acrylamide.
Pile foundations are extensively used to support off-shore and on-shore structures. Under dynamic loads, the behavior of single pile is well understood. However the soil-pile-soil interaction studies are confusing, on which account the analyses do not necessarily predict response of the systems which may match satisfactorily with the performances. In this paper, the nature of dynamic loads is described, and solutions for soil-pile and pile-soil-pile interaction solutions by several authors are presented and a critical evaluation is made.
With the frequent load changes to which a hard coal power station is subjected in the middle and peak load range, great demands are linked with the transient behaviour of the steam generator. Due to the serial connection of the crusher and boiler, the strongly delaying transient behaviour of the crusher compounds entirely with the transient behaviour of the steam generator. Therefore, a suggestion is to be made here as to the improvement of the dynamics of the crusher.
These ten chapters present an overview of floating production, storage and offloading (FPSO) vessels, and examines deep water developments; hydrostatic stability; production, storage and offloading systems; the configuration and structure of flexible risers and umbilicals; the structural and global dynamic analysis of flexible riser and umbilicals; verification of FPSO structural integrity; vessel global loading and rigid body response; environmental loading and vessel response; and mooring systems. (UK)
Load-deflection characteristics of alumina and alumino-silicate fibrous blankets were experimentally determined. Load retention and springback capability of combinations of these materials were measured in a 10,000-hour test at surface temperatures of 650 to 1000"0C (1200 to 1832"0F). Experimental results are presented and future testing plans are discussed.
An analysis of the diagnosis of loading and service dependability of a rail-mounted excavator used in surface lignite mining is described. Wheel power vibrations in electric motor bearings and electric motor input bearings to the gearbox were measured in situ, in horizontal, vertical, and axial directions. The data were analyzed using a mathematical relationship. The results are presented in a loading diagram that shows the deterioration and the acceptable lower bound of machine conditions over time. Work is continuing. 5 refs., 1 fig.
The Fast Flux Test Facility (FFTF) bottom-loading transfer cask (BLTC) system is designed to provide ex-vessel fuel transfers of irradiated reactor components between the reactor containment building and the LMFBR shipping cask in the reactor service building. This system is being procured from National Lead Industries, Wilmington, Delaware, under management of Aerojet Manufacturing Company.
The data center in this study had a total floor area of 8,580 square feet (ft{sup 2}) with one-foot raised-floors. It was a rack lab with 440 racks, and was located in a 208,240 ft{sup 2} multi-story office building in San Jose, California. Since the data center was used only for testing equipment, it was not configured as a critical facility in terms of electrical and cooling supply. It did not have a dedicated chiller system but served by the main building chiller plant and make-up air system. Additionally, it was served by a single electrical supply with no provision for backup power. The data center operated on a 24 hour per day, year-round cycle, and users had all hour full access to the data center facility. The study found that data center computer load accounted for 23% of the overall building electrical load, while the total power consumption attributable to the data center including allocated cooling load and ...
The applicability of conventional strength hypotheses in the long-term creep range was examined by means of multiaxial loaded small and large-scale specimens of 1% CrMoNiV-steel at 550deg C. The experimentally determined deformation behaviour in the primary and secondary creep range was simulated by means of a finite element analysis. The creep deformation capacity is influenced by the degree of multiaxiality. The validity of a strength hypothesis depends on the type of load and on deformation resp. failure criteria. (orig.).
Aluminum hydroxide coating thicknesses were measured on fuel elements stored in aluminum canisters in K West Basin using specially developed eddy current probes . The results were used to estimate coating inventories for MCO fuel,loading. Brushing tests successfully demonstrated the ability to remove the coating if deemed necessary prior to MCO loading.
A novel CFD/structural analysis was performed to predict functionality of a cross parachute under loadings near the structural limits of the parachute. The determination of parachute functionality was based on the computed structural integrity of the canopy and suspension lines. In addition to the standard aerodynamic pressure loading on the canopy, the structural analysis considered the reduction in fabric strength due to the computed aerodynamic heating. The intent was to illustrate the feasibility of such an analysis with the commercially available software PATRAN.
This paper presents actual time/motion data for an oversize truck spent-fuel shipment from its origin, Surry, Virginia to its destination, Idaho National Engineering Laboratory (INEL). These data include the receipt of the empty cask at the reactor, wet-loading the cask, over-the-road or in-transit data, and receipt and dry unloading of the shipping cask at the receiving facility. Occupational doses were recorded at the Surry Power Plant as well as at INEL, and public doses were calculated for the in-transit dose analysis. This shipment was one of a series performed in support of a demonstration and evaluation of dry storage at INEL. The oversized shipment consisted of a TN-8L shipping cask loaded with three 10-yr-old pressurized water reactor assemblies. The total distance traveled was #approx#2800 miles, requiring 62 h including stops. The time required to receive and inspect the empty shipping cask and wet-load and ...
Chitosan-filled rubber compounds were prepared using a laboratory sized two-roll mill. The effect of chitosan loading on three different types of rubber (STR 5L, ENR-25 and SBR) was investigated. The results indicate that, overall, the scorch time (t"S"2), cure time (t"9"0), tensile strength and elongation at break (Eb) decrease with chitosan loading, whereas an increment was observed in the maximum torque (MH) and the tensile modulus (M100 and M300) of all three types of rubber. At a similar chitosan loading, the cure characteristics of SBR were found to be longer (for t"S"2 and t"9"0) and higher (for MH) than those of STR 5L and ENR-25. The tensile properties of SBR were found to be the lowest of the three rubbers at a similar chitosan loading. The rubber-filler interaction for all three...
One of the most loaded parts of a steam generator of VVER 440 MW type are the bolts and thread holes of the primary collector cover sealing set. The strength calculations and tensometric measurings performed during operation proved the high degree of a load on the bolts. The conditions of the stress limitation are not met in some cases according to the pertinent standards. The untightnesses at nickel rings occurred during putting the units of Jaslovske Bohunice and Dukovany nuclear power stations into operation. With regard to improve the reliability, the producer has taken measures to improve the quality of the rings and users have introduced more strict regulations for bolts tightening. Due to these measures the high reliability of the set has been obtained from point of view of the tightness, but substantial reduction of bolts and holes threads loading have not been obtained. Several years operation experience proved ...
Five cycles of loading, elution, and regeneration were performed to remove technetium from a Hanford waste sample retrieved from Tank 241-AW-101 using SuperLig 639 resin. The waste sample was diluted to 4.95 M Na plus and then was processed to remove 137Cs through dual ion exchange columns each containing 15 mL of SuperLig 644. To remove 99Tc, the cesium decontaminated solution was processed downwards through two ion exchange columns, each containing 12 mL of SuperLig 639 resin. The columns, designated as lead and lag, each had an inside diameter of 1.45 cm and a height of 30 cm. The columns were loaded in series, but were eluted and then regenerated separately. The average technetium loading for the cycles was 250 BV at 10 percent breakthrough. There was no significant difference in the loading performances among the five cycles. The percent removal of 99Tc was greater than 99.94 percent and the ...
The Fast Flux Test Facility (FFTF) was designed to test fast-reactor fuels and other nonfuel materials. In its 37 reactor cycles of operations, the FFTF reactor has performed very well and successfully completed all the irradiation testings with an operating efficiency factor as high as 98%. Since FFTF is an experimental reactor, its core loading changed from cycle to cycle. Depending on the number of test assemblies in the core and their location, the core loading can change significantly from an essentially homogeneous core loading to a relatively nonhomogeneous or even highly localized heterogeneous loading. Consequently, the core reload design and initial criticality analyses were required for each operating cycle. The zero power initial critical control rod bank height was predicted before each reactor startup. The initial critical prediction depends on the reactivity conditions at the end of the ...
Vegetation is a key compartment of ecosystems. It contains a large part of the biodiversity at the species level. For the evaluation of critical loads, we have to separate different receptors: lower plants (algae, fungi, lichens and mosses) and vascular plants. Trees must be distinguished due to their economic value. We analyze the different changes that pollution produces on vegetation: the state of health of individuals, changes in the biology and genetics at the population level, changes in the biodiversity or the specific composition at the community level. Calculation of critical loads is based on observational or experimental studies, in more or less controlled environments. However, they cannot yet be obtained through models of vegetation changes. Some results have been acquired at the European level, mainly for critical loads for nitrogen, but these results have come mostly from Northern Europe. Moreover, only ...
Zone modeling permits taking account of the effect of load-relieving air conduction systems in the planning of HVAC plants. Although this only supplies average values for the degree of load and height of the fresh air layer rather than a detailed description of concentration and temperature distributions in the room, it is quite sufficient for the planning of load-relieving air conduction systems. Moreover, the cost of zone modeling in the planning of HVAC plants remains within reasonable limits. Upscale planning, instruments can thus be reserved for more exacting problems. (orig.) [Deutsch] Zonenmodelle erlauben die Wirkung lastmindernder Luftfuehrungen bei der Planung von RLT-Anlagen zu beruecksichtigen. Sie liefern zwar nur Mittelwerte fuer den Belastungsgrad und die Hoehe der Zuluftschicht und keine detaillierte Konzentrations- und Temperaturverteilungen im Raum. Diese Werte reichen jedoch fuer die Planung ...
... This course is jointly taught between the School of Civil Engineering and the Environment and the School of Ocean and Earth Sciences. Scholarships 2 UK/EU fees only Scholarships are available for the academic year 2010/11. Awards will be given on the basis of merit. Flexible part-time study route available Back to top Home | About Us | Prospective Students |...
Energy Related Inventions Program Number 613 was a two year program to commercialize a unique new wear material, Metal Reinforced Carbon Composite, MRCC. The program was designed to manufacture sample components of MRCC for evaluation by potential users and manufacturers. As a result of the program Burton Technologies Inc. and Rotary Power International are forming a joint company to manufacture, market and license MRCC materials to a wide range of industries.
Secretary Cheney's 1990 Annual Report to the President and the Congress established the requirement for the Unified Commanders in Chief to be prepared for Third World conflict involving roles and missions requiring, 'mobile, highly ready, well equipped fo...
We derive the explicit formula for the joint Laplace transform of the Wishart process and its time integral which extends the original approach of Bru. We compare our methodology with the alternative results given by the variation of constants method, the linearization of the Matrix Riccati ODE's and the Runge-Kutta algorithm. The new formula turns out to be fast, accurate and very useful for applications when dealing with stochastic volatility and stochastic correlation modelling.
A new multipellet long-pulse plasma fueling system is in operation on JET. In the initial experimental phase, a variety of plasma density profile shapes have been produced with peak to average values ranging up to 2.5 and peak plasma density up to 1.2 )times) 10/sup 20/m/sup )minus/3). 7 refs., 4 figs
The International Union of Geodesy and Geophysics reports on activities undertaken in the study of global climate change. Some of these activities are a part of the overall International Geosphere Biosphere Program but others predate that program. The organization has been solely responsible for five of ten permanent global data services and jointly responsible for three others. Workshops and meetings devoted to issues of global change are also reported.
The approach estimating the leak probability of flanged joint due to the destruction of fastening studs is described. The mentioned approach consists of two stages. The probability of destroying one stud is calculated at the first stage, and the probability of different combination interpositions of intact and destroyed studs is calculated at the second one. The probability calculation of leak in the area of collector cover of steam generator PGV-1000 is used as an example of developed approach
A summary of the topics covered in papers presented at the 1995 Brookhaven joint conference on production, neutralization, and application of negative ion beams is given. The conference topics covered included plasma ion sources, plasma seeding of these sources for increased ion production, beam extraction and transport, computer simulation and design studies, and operation of existing and experimental ion source facilities. Application of the sources to accelerator, tokamak, and thin film deposition are discussed. (AIP) {copyright} {ital 1996 American Institute of Physics.}
This paper dealt with the identification of possible damaging mechanism of the collector of the WWER 440 steam generator, cracking of primary collectors, corrosion damage of the protective coat of the primary collector circumferential weld, cracking of breathing space in the region of blinding effect by corrosion and strain, leaking of disassembling joint of the primary collector lid and with the integrity of heat exchanging tubes.
A detailed definitive cost estimate is given for an ethanol/gasohol storage and blending terminal serving a planned distillery at a Louisiana sugar factory. Included are an analysis of the accuracy of the estimate, labor rates efficiency, materials and labor escalation, as well as detailed calculations for each account of the project. (LEW)
The document, based on European guidelines, was jointly developed by radiation oncologists, radiation physicists and radiation technologists. It contains the aims of the guidelines, professional profiles, roles and responsibilities, personnel and equipment requirements, procedures.
This book is organized under the following headings: Electrohydrodynamic heat transfer augmentation; Forced convection augmentation and heat transfer control; Turbulent heat transfer; Thermal problems in the environment; Energy conversion systems; Measurement, visualization, and imaging; Thermal problems in space technology; and Thermal properties.
The tendency of welded joints from 10Kh14AG15 and 10Kh14AG9 steels to pitting corrosion under the conditions of operating blast-furnace gas purification scrubbers has been investigated. Water in scrubbers contains various quantities of chlorides and sulfates, has pH from 6 to 9 and temperature 65-75 deg. The laboratory corrosion tests have been carried out also on samples turned from the heat-affected zone (h.a.z.) of welded plates at 20 and 65 deg. Anode polarization curves have been read from the Vk corrosion potential at potential shifting rate 0.01 V/min. It is established that in most rigid conditions of scrubbers operating pitting corrosion (PC) rate of chrome-manganese nitrogen-containing steel can reach 2.5 mm/year. At high content of chlorides in water the elevated temperature and external tensile stresses intensify PC. The resistance of welded joints to PC when using welding materials on chromonickel molybdenum base is determined in ...
...as agro forestry subject matter specialist, eastern supervisor, conservation and GIS officer with the Ministry of Agriculture and WWF-Korup national park project, respectively, in south west Cameroon . Peter holds joint Honours BSc in Forestry & Soil Science (WALES-UK) and MSc Resource Management (Edinburgh-UK)....
This report forms part of a joint study on a PEFC propulsion system for surface ships, summarized in a presentation to this Seminar, entitled {open_quotes}Study on a Polymer Electrolyte Fuel Cell (PEFC) Propulsion System for Surface Ships{close_quotes}, and which envisages application to a 1,500 DWT cargo vessel. The aspect treated here concerns an experiment in reducing by methanation to a level below 10 ppm the CO that is contained to around 1% in reformate gas.
The IAEA Department of Safeguards established a project in 1996 for the year 2000 (Y2K) conversion activities. This project covered assessment, conversion and testing of the software applications, instrument evaluation software, embedded systems and Personal Computer (PC) hardware attached to various equipment. Significant progress has been made in converting the applications and instruments to be year 2000 compliant. At the same time Member states have made an effort as well in converting the systems used jointly at the facilities
This report is designed to cover the overall Operation Castle radiological safety matters from the viewpoint of those issues of direct concern to Headquarters, Joint Task Force Seven. It was written for the express purpose of assisting in the development of future radiological safety plans by presenting detailed discussion of the problems and solutions arising during Operation Castle.
This report is designed to cover the overall Operation Castle radiological safety matters from the viewpoint of those issues of direct concern to Headquarters, Joint Task Force Seven. It was written for the express purpose of assisting in the development of future radiological safety plans by presenting detailed discussion of the problems and solutions arising during Operation Castle. Included is a discussion of fallout forecasting techniques.
Already, MR Imaging is superior in diagnostic imaging of joints in many cases; however, there have been recent developments, which are the subjects of this paper. With gradient-echo sequences acquired in 3D technique, it is possible to produce high-resolution images of joints in acceptable scantime, because gradient-echo sequences are less time-consuming than convential SE sequences. With the acquisition of two echoes, phase difference between water and fat protons have to be considered. 3D Imaging is capable of displaying complex pathology in a superior way, which should be useful in preoperative planning. Tissue contrast is altered by fat saturation or magnetization transfer in order to achieve better conspicuity of lesions. Although diagnostic value of some of these options is not yet clear and further clinical studies are needed, they are a promising possibility for improving MR Imaging of the joints. (orig.) [Deutsch] ...
The importance of neutron measurements both as a succinct measure of the progress to fusion ignition using the magnetic confinement route and also as a diagnostic of plasma conditions is discussed. The various neutron diagnostic systems that have been or are being constructed by AERE Harwell for JET are described. The properties to be measured by such diagnostics are clearly identified and some results obtained with the installed diagnostics during d-d plasmas are presented.
... This study catalysed  a more comprehensive collaborative research programme, Assessment of the durability and engineering properties of lesser known hardwood timber species for use in marine and freshwater construction, jointly funded by the Environment Agency and TRADA, and managed by H R Wallingford. Additional funding was provided by British Waterways, The Crown Estate, CETMEF (Centre d'Etudes Techniques Maritimes et Fluviales) and VolkerStevin Ltd. Timber ...
Monte Carlo calculations performed to validate observed capture reaction rates of "1"2"9I and "2"3"7Np were in a reasonable agreement with experimental data obtained by the Joint Institute for Nuclear Research. The most significant discrepancy between the measurements and calculations (within a factor of 3) was observed for the NpO_2 sample and Pb target at 3.7 GeV proton energy
Are you interested in beam dynamics? Do you work on the LHC injectors or CLIC or maybe feasibility studies fornew machines? Then this is for youJAS'2000: Joint CERN-Japan-JINR-Russia-US SchoolFrontiers of Accelerator Technology: High Quality Beams to be held on a river boat between St. Petersburg and Moscow 1 to 14 July 2000. For further information see eitherhttp://schools.web.cern.ch/Schools/CAS/ orhttp://www.indiana.edu/~uspas/programs/js/jas2000.html
In a joint study conducted by the University Clinic of Radiology, Graz, and the Medical University Clinic, Innsbruck, the results of computer tomography examinations of the abdomen and pelvis in 23 cases of tumours in children are discussed. In children computer tomography resents special difficulties on account of the very poorly developed fatty layers between the organs and the increased incidence of movement artifacts. The importance of computer tomography for the diagnosis of abdominal and pelvic tumours is discussed.
Daya Bay Nuclear Power Station is the largest joint-venture project which is also the largest commercial nuclear power plant currently under construction in China mainland. Organized and executed strictly in accordance with international standards, the Daya Bay project is seen as the first step taken by China in the development programme of large-capacity commercial nuclear power units.
DescriptionThe initiative on risk assessment and toxicology arose in 1995 when the limitations of current methods of risk assessment and the possibilities offered by new options were identified. Government Departments agreed to explore with the Research Councils how a joint strategy could be focused on the Departments' policy needs. In October 2002 the Steering Committee reviewed the work of IGHRC and recommended that the Initiative should continue for a further three years (October 2003 - September 2006 [continued...
The question about expanding the boundaries of the open pit mining method is examined. The use of methods which consider the advantages of open and underground mining operations with their joint use in horizontal and evenly dipping deposits will make it possible to objectively select the mining method, to expand the range of use of open pit mining operations in the deposits of the Far North and provide an improvement in the technical and economic indicators of mineral extraction.
The motivation for this design study has been to identify magnet designs for useful magnetic fusion experiments which minimize capital cost. Some possibly useful novel design features have been identified. 5 refs., 6 figs., 3 tabs.
DescriptionThis project continues DEFRA's commitment to the International Programme on Chemical Safety, a joint WHO/ILO/UNEP programme. DEFRA's contribution involves preparing Environmental Health Criteira Documents (EHCs), Concise International Chemical Assessments Documents (CICADS) and input to the OECD test Guidelines Programme and gneral risk assessment guidance. Peer reviews of documents prepared through other research in the IPCS network have also been carried out,as well as attending and hosting ta [continued...
A centering device for casing tubings is proposed. It includes a housing, collar made of copper linings, return springs and pusher with centering pins placed in it. In order to simplify the design of the centering device it is equipped with levers installed on the pusher rod and connected by hinges to one another. The centering device assures coaxial placement of tubes over the mouth of wells and installation of butt joints during welding of tubes.
The paper will report the experience gained in the implementation of the national assistance projects, including the detailed assessment of the national situation compared to the ITWG Model Action Plan, the upgrading of the technical skills, the training of national experts and the joint analysis of nuclear material at ITU. The status of the work with the 13 future Member States to the European Union will also be reported on during the conference
... Boreal Forest and Climate Change Pertti Hari, Liisa Kulmala, 160.45 EUR; 209.00 USD; 135.00 GBP... More Journals » MAGAZINES & JOURNALS Journal of Water and Health The journal represents a joint commitment to pr... Environmental Quarterly - 2009 Fall Trinity`s Environmental Quarterly (EQ) magazine co... ...
The Lawrence Livermore National Laboratory (LLNL) is establishing a local chapter of the University of California Energy Institute (UCEI). In order to most effectively contribute to the Institute, LLNL sponsored a workshop on energy and environmental issues in transportation. This workshop took place in Livermore on August 10 and brought together researchers from throughout the UC systems in order to establish a joint LLNL-UC research program in transportation, with a focus on energy and environmental impacts.
In this study, a range of joining technologies has been investigated for creating attachments between refractory metal and Ni-based superalloys. Refractory materials of interest include Mo-47%Re, T-111, and Ta-10%W. The Ni-based superalloys include Hastelloy X and MarM 247. During joining with conventional processes, these materials have potential for a range of solidification and intermetallic formation-related defects. For this study, three non-conventional joining technologies were evaluated. These included inertia welding, electro-spark deposition (ESD) welding, and magnetic pulse welding (MPW). The developed inertia welding practice closely paralleled that typically used for the refractory metals alloys. Metallographic investigations showed that forging during inertia welding occurred predominantly on the refractory metal side. It was also noted that at least some degree of forging on the Ni-based superalloy side of the joint was necessary to achieve ...
This is the second revision of the ETDE/INIS Joint Thesaurus, including all updates up to September 2006. It contains 21 147 valid descriptors and 9 114 forbidden terms. The Joint Thesaurus contains the controlled terminology for indexing all information within the subject scopes of the International Nuclear Information System (INIS) and the Energy Technology Data Exchange (ETDE). The terminology is intended for use in subject descriptions for input or retrieval of information in these systems. The thesaurus is a terminological control device used in translating from the natural language of documents, indexers or users into a more constrained system language It is also a controlled and dynamic vocabulary of semantically and generically related terms which covers a specific domain of knowledge. The basic terminology in this thesaurus goes back to the 1969 edition of the EURATOM Thesaurus. The structure subsequently given to that terminology was ...
One of the limiting contributors to the heat load constraint for a long term spent fuel repository is the decay of americium-241. A possible option to reduce the heat load produced by Am-241 is to eliminate it via transmutation in a light water reactor thermal neutron environment, in particular, by taking advantage of the large thermal fission cross section of Am-242 and Am-242m. In this study we employ lattice loading optimization techniques to define the loadings and arrangements of fuel pins with blended americium and uranium oxide in boiling water reactor bundles, specifically, by defining the incineration of pre-loaded americium as an objective function to maximize americium transmutation. Subsequently, the viability of these optimized lattices is tested by assembling them into bundles with Am-spiked fuel pins and by loading these bundles into realistic ...
Due to the cyclical human life, utility loads appear to be cyclical too. During daytime when most factories are in operation, the electricity demand is very high. On the contrary, when most people are sleeping from midnight to daybreak, the electric load is very low, usually only half of the peak load amount. To meet this large gap between peak load and light load, utilities must idle many generation plants during light load period while operating all generation plants during peak load period no matter how expensive they are. This low utilization factor of generation plants and uneconomical operation have sparked utilities to invest in energy storage devices such as pumped storage plants, compressed air energy storage plants, battery energy storage systems (BES) and superconducting magnetic energy storage systems (SMES) etc. Among these, ...
A simple approach to controlling the loading percentage and size of zero-valent iron nanoparticles (ZVI NPs) immobilized within polyacrylic acid (PAA)/polyvinyl alcohol (PVA) nanofibrous mats for dye remediation applications is described. A functional "nanoreactor" comprised by electrospun PAA/PVA nanofibers served to bind ferric ions with the carboxyl groups of PAA, prior to their reduction to ZVI NPs. The resulting ZVI NP-immobilized hybrid polymer nanofibers were characterized using scanning electron microscopy, transmission electron microscopy, and thermogravimetric analysis. The morphology of the polymer nanofibers exhibited no appreciable change even after eight cycles of ferric ion binding/reduction, and the loading percentage and size of the ZVI NPs were controlled simply by varying the number of ferric ion binding/reduction cycles. Dye remediation experiments revealed that the decoloration effect of ZVI NPs immobilized within the ...
Nitrate microelectrodes and ORP microelectrodes were fabricated to study the denitrification characteristics of dynamic membrane at different COD loadings. The denitrification process was found at 0.6-1 mm depth beneath the interface of biofilm/bulk. The results of ORP microelectrode also demonstrated that the ORP value in the range of denitrification area was between 88.6 approximately -128.4 mV which was appropriate to denitrification. When the COD loading was 0.45 kg/(m3 x d), the denitrification rate (NO3- -N) was the maximum of 0.6347 x 10(-6 mol/(L x s). With the increase of COD loading, the denitrification area was increasing and two layers with different denitrification rates emerged in the dynamic membrane. The phenomenon implied the effect of organic concentration, oxygen concentration and bacterial competition on the denitrification rate. PMID:17117632
In general, the tickover speed of a car engine is made sufficiently high, in order to permit an assumed maximum load to be taken from the engine at tickover. This setting of the tickover speed is usually done by stops in the fuel supply. Matching the actual load would lead to lower fuel consumption, without any danger of the engine stalling. The purpose of the invention is to provide a tickover speed controller, so that the tickover speed is adjusted by electronic control equipment, independently of the machine load. The fuel consumption on tickover is reduced and the emission of noxious substances is decreased. The electro-magnetic control of the throttle valve tickover setting is explained by extensive section drawings of the system. This process dispenses with the special tickover cams for a cold start.
Power loadings experienced by tokamak plasma-facing components during normal operation and during off-normal events are discussed. A model for power and particle flow in the tokamak boundary layer is presented and model predictions are compared to infrared measurements of component heating. The inclusion of the full three-dimensional geometry of the components and of the magnetic flux surface is very important in the modeling. Experimental measurements show that misalignment of component armour tile surfaces by only a millimeter can lead to significant localized heating. An application to the design of plasma-facing components for future machines is presented. Finally, thermal loads expected during tokamak disruptions are discussed. The primary problems are surface melting and vaporization due to localized intense heating during the disruption thermal quench and volumetric heating of the component armour and structure due to localised impact of ...
In order to match the output capacity of a geothermal heat pump system (GHPS) with the actual load requirement, research has been conducted in searching for suitable adjusting methods for the GHPS and on the subsequent effects on the working parameters of the GHPS. Firstly, several methods are compared, and it is found that the method of adjusting the compressor's rotation speed using a transducer is better than the others. Secondly, this method is experimented on a small scale GHPS at frequencies ranging from 30 to 55 Hz. The analysis of the experimental data reveals the relationships between the compressor frequency and other important parameters, such as coefficient of performance, heat capacity, cool capacity and compressor power input. The conclusions in the paper can serve as some guidance to the load adjustment of GHPS. (Author)
This paper is concerned with the fracture analysis of thin cylindrical shells subject to secondary bending stresses with some degree of elastic follow-up. A P.Y.F.M. failure assessment route is utilised for an initial investigation. Results are presented graphically and indicate the differences obtained by considering the stresses as primary or secondary in nature. The Jsup(*) contour integral is computed from the results of a non-linear finite element analysis of a thermally loaded cracked cylinder. Comparison is made between Jsup(*) and the P.Y.F.M. failure criteria demonstrating the degree of conservatism in the latter. It is observed that LEFM may be appropriate for moderate load levels but that the elastic follow-up of the structure causes enhancement of Jsup(*) for higher loads, at which stage LEFM becomes non-conservative. (orig.).
In order to perform the structural analysis and stress evaluation for frame structures in the nuclear power plants, ADAMS (AIJ Design Analysis and Modules System) has been developed by the addition of the following functions to the ICES-STRUDL system. 1. Load combination and stress evaluation on the basis of specifications for designing steel structure (issued by the Architecture Institute of Japan). 2. Combination of load and stress evaluation of piping support on the basis of the regulations of Ministry of International Trade and Industry. 3. Addition of other functions than that described above. ADAMS enables structural analysis and stress evaluation exactly and efficiently not only for a large scale structure such as the pipe whip protection structure installed inside of the primary containment vessel for many loading cases but also for a large number of structures such as piping support. This system can be applied not ...
A distributed watershed hydrologic model soil and water assessment tool (SWAT, 2000 Version) was applied to simulate stream flow and nutrient loadings (including total nitrogen (TN) and total phosphorus (TP)) in Gucheng Lake Basin, which is located in the lower reach of Yangtze River Basin. Model parameters related to stream flow and nutrient loadings were calibrated and validated by the observed value, and the simulation showed that the simulated values were reasonably comparable to the observed data, suggesting the validity of SWAT model. The simulated surface runoff and nutrient yield between two stages, viz. 1981-2000 and 1951-1960, were compared, basically considering land reclamation in the mid-1970s. The result indicated that, the average annual runoff and output of TN and TP in 198...
A new controlled-clearance pressure balance is under development with the aim of improving the hydraulic high-pressure standard up to 1 GPa. This pressure balance consists of three parts: (i) a pressure generation device up to 1 GPa, (ii) a weight-loading unit which can load/unload weights automatically and independently, (iii) a controlled-clearance piston-cylinder which is designed to allow the jacket pressure to be applied independently. Some adjustments were made for loading heavy weights on/off the piston safely, keeping them in balance, then generating the pressure stably. Stability of the generated pressure was checked for several piston-cylinders, and it was found that pressure fluctuation was less than a few parts per million. The jacket pressure coefficient of a 500 MPa controlled-clearance piston-cylinder was precisely evaluated as a function of both the system pressure and the jacket pressure.
The ability of the /sup 252/Cf-source-driven neutron noise analysis method to measure subcriticality has been demonstrated in a variety of experimental configurations of fissile materials. Calculations for an approximately 4-m-dia configuration of light water reactor (LWR) fuel elements indicated the feasibility of measuring the subcriticality of large, loosely coupled arrays of LWR fuel elements by this same method. These analysis suggested application to the initial loading of both pressurized and boiling water reactors, zero-power testing of reactors (such as shutdown margin measurements after initial loading), light water reactor refueling, and safe storage of LWR spent fuel. In the fuel storage application, direct measurement of subcriticality in the actual fuel storage facilities provides the parameter which is directly related to criticality safety.
The influence of engine operating variables on the performance, emissions and heat release in a compression ignition engine operating in normal diesel and dual-fuel modes (with natural gas fuelling) was investigated. Substantial reductions in NO{sub x} emissions were obtained with dual-fuel engine operation. There was a corresponding increase in unburned hydrocarbon emissions as the substitution of natural gas was increased. Brake specific energy consumption decreased with natural gas substitution at high loads but increased at low loads. Experimental results at fixed pilot injection timing have also established the importance of intake manifold pressure and temperature in improving dual-fuel performance and emissions at part load. (Author)
A compression ignition engine was operated on dual fuel principle inducting two commercial fuels and four pure hydrocarbon fuels in turn through intake manifold along with air and injecting diesel fuel to initiate the combustion in the conventional manner. The engine was operated at different loads and at each load the quantity of inducted fuel was increased gradually till knocking set in. The engine performance and exhaust pollutant emissions were recorded at different operating conditions. It was observed that the extent of induction and the effect on the performance depend on the properties of the inducted fuel such as volatility, self ignition temperature and oxidation characteristics. The energy release during the cycle was also observed to shift depending on the properties of inducted fuel. With the dual fuel operation, the thermal efficiency at part loads was observed to be less compared to neat diesel operation. The ...
Summary. Ratiometric fluorescent dyes are often used to monitor free ion concentrations in vivo, especially in cells that are recalcitrant to transformation with genetically encoded fluorescent markers. Although intracellular dye distributions are often found to be cytosolic, dye localisation has often not been examined in detail. We began exploring the use of BCECF (2?,7?-bis(2-carboxyethyl)-5(6)-carboxyfluorescein) to monitor pH in the giant alga Chara australis and discovered that younger leaf cells could be loaded using the acetoxymethyl ester of BCECF. However, we were puzzled to find in microphotometric measurements that the fluorescence ratio appeared insensitive to manipulations affecting cytosolic pH. Confocal imaging of C. australis cells loaded with BCECF showed an accumulation ...
The Department of Energy has proposed a rulemaking process to set minimum standards for the efficiency of gas ranges under the National Appliance Energy Conservation Act (NAECA). The Gas Research Institute is compiling information on annual household range gas usage in order to prepare a response to the proposed rulemaking. The data base from the Northern Illinois Gas residential load study provides recent information (data taken from 1990 through 1992) over a comprehensive study of household types and appliance and user characteristics (150 variables noted for each household). The stated Objective is to study the Northern Illinois Gas residential load study data base and to evaluate its effectiveness in predicting annual household gas usage.
The mechanical stability of diamond-like carbon (DLC) films coated on nitinol vascular stents was investigated under cyclic loading condition by employing a stent crimping system. DLC films were coated on the vascular stent of a three dimensional structure by using a hybrid ion beam system with rotating jig. The cracking or delamination of the DLC coating occurred dominantly near the hinge connecting the V-shaped segments of the stent where the maximum strain was induced by a cyclic loading of contraction and extension. However the failures were significantly suppressed as the amorphous Si (a-Si) buffer layer thickness increased. Interfacial adhesion strength was estimated from the spalled crack size in the DLC coating for various values of the a-Si buffer layer thickness.
Bags of explosive are loaded rapidly into deep wellbores by suspending a rigid positioning tube partway into the wellbore, and loading the bags into the tube, the bags being prevented from dropping through the open bottom end of the tube by a cord attached to the lowermost bag and secured at the upper end of the tube when the tube-suspending cable is in tension by a cordsecuring/releasing means, E.G., a pivotable bar having a hook on one end. When the bag-laden tube is lowered to the bottom of the wellbore, or to a column of bags previously placed therein, the tension on the cable is relaxed and the cord is released, allowing the positioning tube thereafter to be raised to the surface for re-use, leaving the cord and bags in the wellbore. Freedom of the bag-supporting cord to move with respect to the positioning tube when the latter is raised to the surface is assured by threading the cord through plastic tubing mounted to the wall of the ...
In the WWER-440 reactor the primary piping consists of six horizontal loops going radially from the pressure vessel, each loop having a horizontal steam generator. In this reactor type the relatively long primary piping with many curved sections requires special attention in order to successfully eliminate the consequences of the design basis accident. Emergency supports are located in appropriate places to restrict the movements of the pipe. Under normal conditions there is a gap of some centimeters between the pipe and a support so that in the pipe can be deformed freely under changing loads. This paper deals with those energy-absorbing structures used at the Loviisa Nuclear Power Plant for protection against impact loading. Places and circumstances where energy-absorbing structures are employed are specified. Development and design of impact absorber elements are discussed and impact tests are described. (Auth.).
Investigations were conducted on the range of emission rates of NO, NO[sub 2], CO and hydrocarbons, and the thermal efficiencies produced by each burner on three production cookers, supplied by different Australian manufacturers. It was found that the emissions and efficiencies were markedly affected by (1) the thermal input, both with and without a load on the burner, and (2) the load-height to flame-length ratio, with a load on the burner. The effect of hydrocarbon leakage into the secondary/dilution air was investigated, to explain the observed correlation of hydrocarbon emission rate with dilution air flow. The hydrocarbons were found to arise from two sources: -leakage from the stabilisation ports at the base of the burner, which was found to be significant at the higher thermal input; -incomplete combustion of the fuel in the premix, which was the dominant source of hydrocarbons emissions at the lower thermal input. ...
The authors obtain the critical load levels corresponding to the onset of spalling microdamage for Armco iron and steels St.3 and 12Kh18N10T in a broad temperature range (-196-800 degrees C. The results of the investigation of the effect of the temperature on spalling fracture are presented. The effect of the loading time on the strength of the investigated materials is also given. The authors assume that at -196 degrees C impact-wave strain-hardening may also be characterized by the value of H obtained for the center of the specimen since measurements on great thicknesses, including those reaching as far as the opposite surface, did not reveal any substantial change of microhardness.
ABSTRACT Purpose: The aim of this two-center study was to evaluate screw-type titanium implants with a chemically modified, sandblasted and acid-etched surface when placed in the posterior maxilla or mandible, and loaded 21 days after placement. Material and Methods: All 56 patients met strict inclusion criteria and provided informed consent. Each patient displayed either a single-tooth gap, an extended edentulous space, or a distal extension situation in the posterior mandible or maxilla. Eighty-nine dental implants (SLActive, Institut Straumann AG, Basel, Switzerland) were inserted according to an established nonsubmerged protocol and underwent undisturbed healing for a period of 21 days. Where appropriate, the implants were loaded after 21 days of healing with provisional restorations i...
Process engineers can predict quickly and accurately the equilibrium behavior of simultaneous H/sub 2/S and CO/sub 2/ absorptions in monoethanolamine and diethanolamine systems by using the nomographs developed by H.K. Ferguson Co. Correlation lines for temperature and amine concentration provided with the loading curves make the nomographs useful for any combination of temperature, concentration, and liquid loadings. The accuracy of the nomographs is within the acceptable range for normal engineering applications when the operating parameters lie in the region of practical gas-treating conditions. Correction curves given for each nomograph to improve the accuracy are generally not needed except for cases where the gas loadings are higher than 0.5 mole/mole of amine.
Microstructural observations of damage around indentations in Ti{sub 3}SiC{sub 2} are presented. The Vickers hardness decreased with increasing load and asymptotically approached 4 GPa at the highest loads. No indentation cracks were observed even at loads as high as 300 N. Preliminary strength versus indentation plots indicate that, at least for the large-grained material ({approx}100 {micro}m) studied here, Ti{sub 3}SiC{sub 2} is a damage-tolerant material able to contain the extent of microdamage to a small area around the indent. The following multiple energy-absorbing mechanisms have been identified from scanning electron micrographs of areas in the vicinity of the indentation: diffuse microcracking, delamination, crack deflection, grain push-out, grain pull-out, and the buckling of individual grains.
The operation of pumped-storage plants (PSP) is based on the daily load variations of power demand. It performs power generation at peak load times during the day, and pumps water up into the reservoir during the off-peak times at night. In the Taipower system in Taiwan, there are two pumped storage plants with ten units. These had a total installed capacity of 2,602 MW or a 12 percent capacity at the end of 1995. The plants were able to reduce system generation costs and improve reliability. A Pumped-Storage Plant Benefit Analysis (PSPBA) program was established using the principle of economic dispatch in 1985. This paper explains the rules of the program, the analysis results of the past 10 years, and a a cost benefit evaluation. It was found that the advantages of PSP are not only in supplying the power for peak load, but also in decreasing the total fuel cost. 5 figs., 4 refs.
A non-resonant RF cavity loaded with amorphous alloy cores has been designed and tested. The cavity has a re-entrant structure loaded with 8 amorphous alloy toroidal core and its characteristic impedance is designed as 450 Omega . The RF power is fed by 1 kW solid state amplifier using a step-up transformer with 1:9 impedance ratio. In the high power test, an accelerating gap voltage of more than 900 V was measured with input power of 1 kW in the frequency range of 1 to 10 MHz. The voltage standing wave ratio (VSWR) was less than 2.0. The results prove that the cavity may be used successfully within a compact proton synchrotron for a cancer therapy facility. (3 refs).
In recent years, interest in the development of a polymer electrolyte fuel cell (PEFC) has considerably increased due to its advantages (e.g., high power density) compared with other fuel cell systems, and its potentials to become the power plant for the next generation, nonpolluting automobile engine. For large scale application of fuel cells, low platinum loading electrode structures are necessary. An electrode based on a highly porous carbonized polyacrylonitrile foam material with very low platinum loading ({approximately} 13 {micro}g/cm{sup 2}) was prepared. The performance of this electrode for oxygen reduction was evaluated and compared with bulk platinum and glassy carbon electrodes.
This report describes the accomplishments of the University of Georgia in establishing an academic program geared toward the emerging biobased products industry. By virtue of its strengths and structure, the University of Georgia is particularly well-suited for developing a program focused on plant- and microbial-based bioproducts, and it was in this general area that this program was developed. The program had several unique characteristics. First, we implemented a distinguished lecture series that brought outstanding scientists and engineers to our University to interact with students and share their vision of the biobased economy. Second, we offered industrially-oriented and multidisciplinary courses that provided students with a broad background on various facets of biobased business and technology. Third, we provided the students with opportunities to expand beyond the classroom by engaging in research lab rotations and industrial internships. Fourth, each ...
This report covers the first year of operation of a fuel cell power plant, installed by PPL Spectrum, Inc. (PPL) under contract with the United States Coast Guard (USCG), Research and Development Center (RDC). The fuel cell was installed at Air Station Cape Cod in Bourne, MA. The project had the support of the Massachusetts Technology Collaborative (MTC), the Department of Energy (DOE), and Keyspan Energy. PPL selected FuelCell Energy, Inc. (FCE) and its fuel cell model DFC{reg_sign}300 for the contract. Grant contributions were finalized and a contract between PPL and the USCG for the manufacture, installation, and first year's maintenance of the fuel cell was executed on September 24, 2001. As the prime contractor, PPL was responsible for all facets of the project. All the work was completed by PPL through various subcontracts, including the primary subcontract with FCE for the manufacture, delivery, and installation of the fuel cell. The manufacturing ...
Blade fatigue life is an important element in determining the economic viability of the Vertical-Axis Wind Turbine (VAWT). A principal source of blade fatigue is thought to be the stochastic (i.e., random) aerodynamic loads created by atmospheric turbulence. This paper discusses the development of a model for the simulation of these stochastic loads, given the rotor geometry, operating conditions, and assumed turbulence properties. A Double-Multiple-Streamtube analysis is employed, which includes the effects of wind shear. Reynolds number variations, different airfoil sections and chord lengths along the blade span, and an empirical model for dynamic stall effects. Calculations are presented for the VAWT 34-m Test Bed currently being assembled at Bushland, Texas. Time histories of the loads, as well as their Fourier spectra, are presented and discussed. An unexpected finding is that the average output power is predicted to ...
Most pumped-storage plants have the capability to operate as synchronous condensers. As such, they can be brought on line very quickly to support system load requirements. However, one of the effects of making a rapid transition from synchronous condenser operation to turbine/governor operation is an initial reverse power flow into the machine. This reverse power flow can be very undesirable at a time when the system is calling for load support. On weak or isolated systems, this reverse power flow can lead to objectionable voltage and frequency dips in the system. With the proper utilization of a static frequency converter (SFC) and its associated controls and auxiliary switchgear systems, the reverse power flow resulting from a transition from synchronous condenser operation can be eliminated. This paper will describe the method by which an SFC system can be used to make this rapid load response in pumped-storage plants ...
This work presents an analysis of the operation of a multi-cylinder, tubro charged, indirect injection diesel engine from a second-law analysis point of view. For this purpose, a single-zone thermodynamic model following the filling and emptying modelling technique is developed. A second-law analysis is performed in all parts of the diesel engine plant, which provides all the existing availability terms and accounts for the evaluation of every component`s irreversibilities. A complete second-law terms tabulation is given for the maximum speed-full load operation case, which is compared with its first-law counterpart. A detailed parametric study is performed in all parts of the diesel engine plant comprising the effects of speed and load on the availability terms in a range that covers the whole operation of the engine under turbocharged action. Various second-law (availability) terms such as indicated and brake work, heat transfer, inlet air, ...
The article presents measures for the solution of construction-biological problems and for reducing the pollutant load of buildings. (HW) [Deutsch] Der Artikel berichtet ueber Massnahmen ueber Sanierung von baubiologischen Schwachstellen und Schadstoffbelastungen in Gebaeuden. (HW)
Purpose: In an experimental study, the correlation between the trabecular bone density of the different regions of the proximal femur and the fracture load in the setting of femoral neck fractures was examined. Methods: The bone mineral density 41 random proximal human femora was estimated by single-energy quanitative CT (SE-QCT). The trabecular bone density was measured at the greatest possible extracortical volume at midcapital, midneck and intertrochanteric level and in the 1 cm"3 volumes of the centres of these regions in a standardised 10 mm thick slice in the middle of the femoral neck axis (in mg/ml Ca-hydroxyl apatite). The proximal femora were then isolated and mounted on a compression/bending device under two-legged stand conditions and loaded up to the point when a femoral neck fracture occurred. Results: Statistical analysis revealed a linear correlation between the trabecular bone density and the fracture load ...
Excised sheets of canine myocardium were subjected to cyclic loading and unloading in the predominant fibre and cross-fibre directions to determine passive mechanical properties. Myocardium under biaxial...Full Text Available
The Heliophysics roadmap: "The Solar and Space Physics of a New Era: ..... Improved materials and manufacturing processes to produce Iridium/Rhenium apogee class ... In addition to batteries, other advanced energy storage/load leveling ...
The water permeability of tissues was investigated by measuring the efflux of 3HHO from previously loaded (in darkness) etiolated bean buds (Phaseolus vulgaris L. var. Red...Full Text Available
Background:Stem cells can differentiate into multiple cell types, and therefore can be used for cellular therapies, including tissue repair. However, the participation of stem cells...Full Text Available
situ by isolating portions of the building envelope and performing tests .MAXIMUM ALLOWED LOAD ...and shall identify commissioning team members who will perform testing and prepare documentation.The commissioning agent may be
Electrical power is generated by steam turbines (steam being produced by coal, oil, gas or nuclear reactors), hydro units, gas turbines, internal combustion engines, jet engines, and pumped storage plants. Nuclear Power Plants generate only 15% of the total electrical power in the US. Nuclear Power Plants being cheaper to run are generally base loaded. The pumped-storage and gas turbine plants have ideal characteristics for peaking duty. In the pumping mode, pumped storage plants are used to provide additional system load and in the generating mode, they supply reactive power during peak load demands. Gas turbine plants have higher running costs, but are used as peaking units with a fast start capability. Fossil power plants need a minimum of 1 hour to stabilize expansion in the boiler and turbine generator. Due to a more competitive power supply market due to deregulation, most of the utilizes plan generation only for the ...
This report documents the collaborative effort between the United States and Canada to investigate the impact of process-induced defects on strength and stiffness under static and fatigue loading and for low-cost composite aircraft structures, in particul...
A numerical technique is developed for estimating water quality violation frequencies due to pollutant discharges from urban areas during combined sewer overflow events. The first four moments of in-stream pollutant concentration are found by integrating a pollutant loading - wat...
A new approach to dynamic security assessment in electric power systems is proposed. A power system is modeled as a dynamical system with random variable structure. Structural variations are caused by primary and secondary events. Primary events are state-independent disturbances representing line and unit faults and load changes and are modeled by random jump processes. Secondary events that represent forced line and unit outages and load sheddings are modeled through an aggregate representation of the protection system as random processes whose change in time corresponds to the crossing of switching surfaces by the state process. These switching surfaces are defined by the setting of the protective relays. Commensurate with this model a three-state decomposition of the operating conditions into normal, emergency, and partial load operating states is suggested. Transitions between these states are described in terms of ...
BackgroundLeukocyte telomere length (LTL) is an emerging marker of biological age. Chronic inflammatory activity is commonly proposed as a promoter of ...Full Text Available
The different radiation loads caused by natural and artificial radionuclides are compared in this paper. This examples will serve to illustrate that the problem of population exposure to radiation can only be solved in consideration of all components and to show which effects of the radiation from natural sources are of special importance in this connexion. (orig./AK).