In this study, the two methods, US NRC and JAERI method, for the determination of scenario earthquakes for seismic design of nuclear power plants based on the probabilistic seismic hazard analysis were reviewed. The scenario earthquakes were developed for the Wolsung NPP site using the PSHA results based on the US NRC Regulatory Guide 1.165 procedures. It seems that the JAERI method is more appropriate to incorporate the effects of individual seismic sources and active faults, and to estimate the multiple ground motion parameters. The magnitude and distance bins of the scenario earthquakes for Wolsung NPP site were M6.4, 9km and M6.2, 13km.
The moderate earthquake of magnitude 5.2 was occurred at the offshore Uljin on the 29 May 2004. The magnitude of the event is the largest one which is equal to that of the Sokrisan earthquake on the 16 September 1978 since the beginning of the instrumental recording by the Korean Metrological Administration (KMA) in 1978. The magnitude of the event was large enough to be felt in a wide area of the southern Korea. It did not affect the safety of the Uljin nuclear power plant (NPP) site which is about 80 km away from the epicenter. In this article, we estimate source parameters of the event and evaluate preliminary seismic safety of the Uljin NPP site regarding the event as an empirical Green's function (EGF)
This report examines the use of probabilistic methods in dealing with the problem of potential earthquake-induced liquefaction of foundation soils at an example dam site located in the central United States, near the New Madrid earthquake zone. The example dam is assumed to be a 1-mile long rolled-filled embankment founded on a 100-ft deep deposit of interbedded alluvial gravels, sands, silts, and clays. The study is seen as an opportunity to examine probabilistic concepts and procedures in the framework of an example engineering project. In this context, the main practical value of a probabilistic approach is that it permits more informed decision making about further data acquisition, additional engineering analysis, and if necessary, remedial action. The specific aim of the study is to show how probabilistic procedures complement and help to reinterpret the results of deterministic (earthquake-induced) liquefaction ...
Some factors affecting the accuracy of magnitude calibration of palaeoearthquakes are discussed. The general problem is illustrated by two case studies. First, the 2003 strong earthquake in the Altai region (Russia-Mongolia border), which has generated co-seismic surface faulting is considered. An analysis is conducted to determine how accurately its magnitude could be defined after 2000 years based on surface faulting parameters, retrieved when future palaeoearthquake studies are launched. This example demonstrates that accurate evaluation of magnitude is possible if specific regional seismotectonic features are taken into account and surface faulting parameters are measured over a dense grid. Next, the Muya earthquake that occurred in the Baikal seismic region in 1957 is studied with res...
Aug 23, 2011 ... Earthquakes, Hurricanes and Stubborn Instruments ... And if earthquakes and stubborn instruments aren't enough, there's this giant hurricane ...
Two additional earthquakes, magnitudes 6.6 and 6.7 occurred the next morning. The first earthquake was located six miles north of Petrolia, California, ...
The purpose of computer program NetMoment (Appendix I) is to utilize fundamental knowledge of earthquake sources, propagation attenuation, and site response in a simultaneous inversion of network data to determine the moment and source corner frequency of earthquakes, and site specific t*. The source parameters are especially difficult to determine for small earthquakes. A fundamental problem in determining the source corner frequencies of small earthquakes is that site response can result in spectral corner frequencies in the range that may be expected from the earthquakes themselves. Several authors have identified this as fmax (Hanks, 1982), a constant corner frequency for small events so that below threshold moment (about 1.0 x 10{sup 21} dyne-cm) the corner frequency remains constant the size of events diminishes. Hutchings and Wu (1990) found that for the ...
At Cazzaso (Friuli) in northeast Italy, radon ("2"2"2Rn) activity concentration in soil gas in a borehole at a depth of 80 cm has been monitored continuously (at a frequency of once an hour) since May 2004, using a Barasol probe (Algade, France). In addition, environmental parameters (air and soil temperature, barometric pressure) have been recorded. The results have been evaluated and the relationship between radon levels and seismic activity is discussed. Correlation between radon concentration and barometric pressure has been observed. Preliminary results have shown a distinct radon anomaly prior to some earthquakes. (authors)
The regular occurrence of large-scale earthquakes in Japan necessitates the use of earthquake disaster prevention systems that focus on gathering damage information on gas supply facilities immediately after an earthquake strikes and minimizing the damage. This paper discussed the development of an earthquake damage estimation system for city gas pipelines that can show damage information in real-time by using earthquake records obtained from densely deployed earthquake observation networks and the most advanced telecommunication and information technologies. The paper summarized the earthquake damage estimation system (EDES) and Toho Gas disaster prevention measures. Specific topics that were discussed included the Toho Gas supply method; earthquake countermeasures; construction of computer systems; normal and emergency ...
Recent earthquake disasters have revealed the importance of countermeasures against soil Liquefaction in seismic design. In particular, the 1995 Hyogoken Nanbu earthquake caused several types of severe damages to pile foundations. This paper describes an analysis method for soil liquefaction using simple parameters such as SPT-N values and seismic response analyses for the pile-supported structure to consider soil-structure interaction effects and soil non-linearity using a modified Penzien model. It is important to find a way to determine the region of surrounding soil whose behavior is identical to that of piles. This paper adopts the thin layer element method to systematically determine the volume of the surrounding soil. The responses of pile-supported structure are similar, whether soil liquefaction and nonlinearity of pile are considered or not. However, the bending moment of pile become large as to soil liquefaction, ...
Laser welding of AISI 904 L super austenitic stainless steel using a diffusion cooled slab 3.5kW CO2 laser and employing two different shielding gases, namely argon and helium, was carried out. The laser weld bead profile depends on various parameters such as beam power (BP), travel speed (TS) and focal position (FP) of the laser spot. These parameters have to be selected suitably to obtain the desirable output. The cross sectioned area of the bead profiles measured using an optical microscope to determine the bead width and depth of penetration. X-ray diffraction used for phase identification confirmed that the weld structure was fully austenitic and dendritic. Hardness was observed to increase in the weld bead with respect to the parent metal and it was related to the microstructural ref...
An elderly man receiving chlorambucil for chronic lymphatic leukaemia developed focal fits. The onset and frequency were dose related. There was no evidence of metabolic disturbance or of meningeal...Full Text Available
Plate-boundary earthquakes have occurred repeatedly in the past several thousand years at the Cascadia subduction zone, where they are widely recorded ... ...
Similitude theory is used to develop scale models for determining the earthquake response of pile foundations embedded in overconsolidated clay. The model is compared with full-scale foundations embedded in natural soil, for which dynamic response measurements had been made in previous work. Correlation of the model and prototype earthquake response constitutes a major difference in this work over previous efforts using scale models. Gravity effects are included in the models by scaling pile and soil material properties. The model pile material is selected to provide the correctly scaled stiffness and mass properties. The required model soil properties are achieved by developing a mixture of bentonite, aerosil, and veegum. Elastic properties of the model soil are compared with those of the prototype by standard monotonic stress and cyclic stress soil tests. It is found that scaling considerations must also apply to supporting static soil tests ...
A mathematical model of multichannel radiometric inspection system was developed, in which the measurement results are reproduced in the form of a half-tone image equivalent to the radiation image of the irradiated object. The model makes the following assumptions: the beam of radiation is fan-shaped; the object of inspection is scanned discretely; the focal spot of the source is rectangular; the apertures of the detector are round, and the detectors themselves are equidistant from the sources, aimed at it, and form a close-packed array; the signals from the detectors are processed according to a time scheme; and the measurement results are corrected in a computer for normalizing the gains of the channels of the system. The mathematical model can serve as the basis for developing a method of calculating the optimal parameters of a multichannel radiometric system with visualization of the radiation images. 14 refs., 2 figs.
Present day mammography has not been able to make use of the advantages of digital luminescence radiography because of the limited spatial resolution. The recent development of electromagnetic focusing X-ray tube with effective focal spot sizes from 0.04 to 0.12 mm allows radiographic direct magnification with less geometric blur. It is now possible to combine direct magnification mammography with digital luminescence radiography. By combining high quality storage phosphor screens with an HQ-workstation a spatial resolution of 8 lp/mm is possible for 1.7-fold magnification. For 4-fold spot magnification views spatial resolution can be theoretically increased to approx. 20 lp/mm. One important advantage of digital radiography is the possibility of image-postprocessing. This article presents two sets of standard parameters and three sets of image dependent parameters for better imaging of specific lesions, such as ...
Several recent improved methods for the EGFM are introduced in order to avoid artificial holes seen in the synthetic acceleration spectrum. Furthermore evaluation of input ground motions at Wolsung NPP are performed by varying the source parameters that may control the high-frequency wave radiation and the deviation of the synthetic motions are revealed. The PSHA case studies for four NPP sites (Wolsung, Kori, Uljin, Younggwang) are performed. In the analysis, site-specific attenuation equations developed for Korean NPP sites are employed, and the seismic hazards for the target sites are evaluated in the case where the four kind of seismic source models are considered. Moreover, the PSHA for Wolsung and Younggwang are conducted by using the site-specific attenuation equation with the index of response spectra and the uniform hazard spectra are evaluated for the two sites. The supporting tool for seismic response analysis and the evaluation tool for evaluating ...
French English ... Orig. Title Imagerie IRM des lesions focales hepatiques avec les antennes de surface en reseau phase (phased array): apnee ou imagerie haute resolution?.
BackgroundThe lack of adequate randomized clinical trials (RCT) has hindered identification of new therapies that are safe and effective for patients with primary focal segmental...Full Text Available
Objective:The aim of this study was to determine if there were focal cortical abnormalities in juvenile myoclonic epilepsy (JME) using neuropsychological investigations and MRI.Methods:Twenty-eight...Full Text Available
We obtained the time-lapse cumulative slip before and after the 29 November 1999, Xiuyan, Liaoning, China, Ms = 5.4 earthquake by using "repeating events" defined by waveform cross-correlation. We used the seismic waveform data from the Liaoning Regional Seismograph Network from June 1999 to December 2006. Two "multiplets" located near the seismogenic fault of the 1999 Xiuyan earthquake and the 4 February 1975, Haicheng Ms = 7.3 earthquake, respectively, were investigated. For the "multiplet" that occurred before and after the 1999 Xiuyan earthquake, apparent pre-shock accelerating-like slip behavior, clear immediate-post-seismic change, and relaxation-like post-seismic change can be observed. As a comparison, for the "multiplet" near the 1975 Haicheng earthquake which occurred a quarter century ago, the cumulative slip appears linear with a much smaller slip rate.
125 Years of Science for America - 1879 to 2004 link to Western Coastal and Marine Geology website U.S. Geological Survey Professional Paper 1687 Marine Geology and Earthquake...
This frequently-asked-questions feature provides answers about earthquakes, faults, plate tectonics, and earth structure. Maps and diagrams are provided with some answers, and links to additional information and to related topics are included.
The devastating earthquake in Sichuan, China on 12 May 2008 left thousands of survivors requiring medical care and intensive rehabilitation. In view of this great demand, the Chinese Speaking Orthopaedic...Full Text Available
... Deepwater Horizon leak in the Gulf of Mexico, the Haitian earthquake and subsequent response, release of information by WikiLeaks, the Icelandic ...
A new dual focal point electro-optic lens that is switchable to focusing and unfocusing is proposed and successfully demonstrated. This electro-optic lens is constructed by coating transparent fine electrodes in the Fresnel-zone plate onto a PLZT ceramic plate. Its focal length changes from 1.25 m to infinity binary at 515 nm with the external voltage of 210 V. PMID:20725208
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 ...
In this paper, the authors describe the characteristics of design seismic input motions and recently observed seismic records of base isolated buildings in Japan. First, we describe some seismic design spectra for building structures which were adopted. Then we show response spectra and energy spectra of observed records obtained during two recent major earthquakes (The 1995 Hyogo-ken Nanbu Earthquake and the 2003 Tokachi-oki Earthquake), which demonstrate the effectiveness of base isolation against large amplitude earthquake ground motion. We also introduce the responses of base isolated buildings during some earthquakes including the Tokachi-oki Earthquake. These data were gathered through questionnaires sent to many engineers who had conducted response observations of base isolated buildings. Last, an example of a base isolated building on soft ground is ...
Detailed investigations of geologic, geomorphic, and seismic conditions at the Bodo Canyon disposal site were conducted. The purpose of these investigations was basic site characterization and identification of potential geologic hazards that could affect long-term site stability. Subsequent engineering studies, such as analyses of hydrologic and liquefaction hazards, used the data developed in these studies. The geomorphic analysis was employed in the design of effective erosion protection. Studies of the regional and local seismotectonic setting, which included a detailed search for possible capable faults within a 65 kilometer radius of the site, provided the basis for seismic design parameters. The scope of work performed included the following: Compilation and analysis of previous published and unpublished geologic literature and maps; Review of historical and instrumental earthquake data; Review of site-specific subsurface geologic data, ...
Faults are being actively investigated across Japan since the Great Hanshin-Awaji Earthquake. Discussed in this report is the application of the 3D near-surface reflection seismic survey in big cities. Data from trenching and drilling is used for the geological interpretation of the surroundings of a fault, and the reflection seismic survey is used to identify the position, etc., of the fault. In this article, when the results obtained from the experimental field are examined, it is found that the conventional 2D imaging reflection survey betrays the limit of its capability when the geological structure is complicated, that the 3D reflection seismic survey, on the contrary, is capable of high-precision imaging and, when augmented by drilling, etc., becomes capable of a more detailed interpretation, and that it also contributes effectively to the improvement of local disaster prevention in big cities. Using as the model the Tachikawa fault that runs near JR ...
A new generation of quasimonochromatic high-flux X-ray sources, based on the X-ray radiation produced through Compton scattering between an electron beam and a laser beam, is under development. One of the possible applications of this source is inline phase contrast mammography, based on the observation of the edge-enhancement effect that can be observed at the border of structures inside the breast in images produced using a partially or totally coherent X-ray beam. In this work we present the results of a set of simulations of inline phase contrast mammography using typical inverse Compton scattering sources parameters. The simulated sample was a tumour-like mass having spherical shape, diameter between 200 {mu}m and 5 mm, placed inside a breast-like matrix, 4 cm thick, and a standard composition of 50% glandular tissue and 50% adipose tissue. We discuss the minimum requirements for mammography using inverse Compton scattering sources and we discuss how the ...
Hayakawa et al. (2009) and Hayakawa (2011) have recently reviewed some "anomalous" ULF signatures in the geomagnetic field which previous publications have claimed to be earthquake precursors. The motivation of this review is "to offer a further support to the definite presence of those anomalies". Here, these ULF precursors are reviewed once again. This brief communication shows that the reviewed anomalies do not "increase the credibility on the presence of electromagnetic phenomena associated with an earthquake" since these anomalous signals are actually caused by normal geomagnetic activity. Furthermore, some of these ULF precursors have just been rebutted by previous publications.
According to the California Earthquake Authority, only about 12% of current California residences are covered by any form of earthquake insurance, down from about 30% in 1996 following the 1994, M6.7 Northridge earthquake. Part of the reason for this decreasing rate of insurance uptake is the high deductible, either 10% or 15% of the value of the structure, and the relatively high cost of the premiums, as much as thousands of dollars per year. The earthquake insurance industry is composed of the CEA, a public-private partnership; modeling companies that produce damage and loss models similar to the FEMA HAZUS model; and financial companies such as the insurance, reinsurance, and investment banking companies in New York, London, the Cayman Islands, Zurich, Dubai, Singapore, and elsewhere. In setting earthquake insurance rates, financial companies rely on models like HAZUS, that ...
In the wake of the 2010 earthquake in Haiti, medical relief organizations and individual practitioners mobilized to provide assistance. Here, an emergency medicine physician who worked with a Louisiana-based...Full Text Available
Healthcare practitioners from around the world responded almost immediately in the aftermath of the 2010 earthquake in Haiti. This article reports on the efforts of an orthopedic trauma team in Haiti...Full Text Available
Mar 2, 2010 ... The NASA/JPL Education Office works with educators -- both classroom teachers and informal educators -- to provide tools, resources and ...
Mar 15, 2011 ... The NASA/JPL Education Office works with educators -- both classroom teachers and informal educators -- to provide tools, resources and ...
In this work tests of quality control in beams of X rays have been carried out, at diagnostic level, of two radiological services equipments of Brazilian hospitals (Aracaju, SE). We obtained the air kerma and kerma rate values, the beams efficiency, the coherence between the luminous fields and the referring fields of irradiation and half-value layer to each equipment and set of parameters. The measures of direct form have been obtained using two ionization chambers, one cylindrical and another one with parallel plates. An optional method for accomplishment some of the tests were carried out with CaSO{sub 4}:Dy + Teflon thermoluminescent dosimeters. The values of air kerma were evaluated for three tube voltage, 40, 60 and 81 kV at 1.0 m from the focus of the equipments. For each one of the voltages three distinct current values were chosen besides a fixed value of exposition time. The results showed that the values of air kerma varied between 8.0 {mu}Gy and 0.35 ...
The docking protein p130Cas is a prominent Src substrate found in focal adhesions (FAs) and is implicated in regulating critical aspects of cell motility including FA disassembly and protrusion of the...Full Text Available
A radon detector with LR-115 nuclear track film was constructed for radon concentration measurements in soil. Temporal radon variations, as well as the barometric pressure, precipitation and temperature were measured for two years. Negative correlation between radon concentration in soil and barometric pressure was found. For some of the recorded earthquakes that occurred during the observation period, soil radon anomalies may be noticed one month before the quakes.
The invention deals with an offshore drilling or production platform in particular designed for quake-active areas. The platform rests on the sea bed with a low-gravitational weight and anchored to stabilized pile foundations absorbing the horizontal and vertical acting forces from earthquakes. The platform including pillars can be made of different materials, prestressed concrete in particular. 3 figs.
The long-range correlation properties in the hourly time variability of geochemical signals measured in a 70 m depth well at Triponzo (Umbria region), are investigated by the detrended fluctuation analysis (DFA). DFA is a data processing method that allows for the detection of scaling behaviors in observational time series even in the presence of non-stationarities. The procedure adopted has allowed for the unambiguous identification of possible correlations among the recorded signals and local earthquakes.
Hyogo-ken Nanbu earthquake with a focus in the Akashi straits has given huge earthquake damages in and around Awaji Island and Kobe City in 1995. It is clear that the basement structure, which is steeply deepened at Kobe City from Rokko Mountains towards the coast, and the focus under this related closely to the local generation of strong ground motion. Generation process of the strong ground motion was discussed using 2D and 3D numerical simulation methods. The 3D pseudospectral method was used for the calculation. Space of 51.2km{times}25.6km{times}25.6km was selected for the calculation. This space was discretized with the lattice interval of 200m. Consequently, it was found that the basement structure with a steeply deepened basement, soft and weak geological structure thickly deposited on the basement, and earthquake faults running under the boundary of base rock and sediments related greatly to the generation of ...
Surface wave tomography method based on analysis of ambient noise is widely used during the last decade. It is assumed that correlated component of noise is composed of surface waves generated by sources distributed over the Earth's surface more or less uniformly. In such a case the cross-correlation function (CCF) at two stations may be considered as the Green's function of surface wave. This function should be symmetric relatively to zero time. However analysis of CCF at the stations located at the East-European Platform shows that as a rule CCF is characterized with a strong asymmetry. Since "purered noise cannot be extracted from seismic records due to superposition of earthquake signals, the method for calculation of CCF includes amplitude normalization for suppression of earthquakes that reduces signals from earthquakes to a noise level. The parts of records containing waves from earthquakes are ...
A segmented focal plane detector for an Enge split-pole spectrograph has been developed for the study of breakup reactions at very low relative energies. It consists of a 61 cm long segmented position-sensitive parallel plate avalanche counter backed by a large Bragg curve detector. A segmented plastic scintillator is mounted behind the anode of the Bragg curve detector and is used for particle identification of low-ionizing particles. The dead space between the two sections of the focal plane detector is 2.5 mm. The intrinsic position resolution of the detector is 1 mm. The intrinsic energy resolution depends on the energy of the incident ion and can be as good as 0.55%. The nuclear charge and mass resolutions are 0.3 e and 0.3 u, respectively. (orig.).
A geological and geotechnical framework was provided in order to facilitate understanding of the damage to structures resulting from soil conditions during the earthquake of January 17, 1995 at Hyogo-ken Nanbu (Kobe), Japan. Special attention was paid to the large scale failures of the quay walls in the port of Kobe, resulting from liquefaction. The performance of structures in improved and unimproved ground were compared. It was observed that locations with some previous site improvements through densification behaved satisfactorily, despite unanticipated high levels of ground motion. Soil-structure interaction problems, such as pile foundations, bridge piers, lifelines, and an underground subway station were also described. Reference was made to the significance of these failures for the seismic design in the Fraser Delta in British Columbia in view of the area`s proneness to liquefaction during a major earthquake. 31 refs., 5 tabs., 45 figs.
This paper reviews generation methods of artificial earthquake motion and proposes an improved method of generating input motions for use in vibration tests of equipment to prove aseismic performance. The improved method employs beat wave repetition characteristic that inherently appears in the component waves of recorded earthquakes decomposed by bandpass filter and algebraic function phase for the component waves. Typical motions generated by the improved method satisfies prescribed severe conditions such as target response spectrum that are defined with a wideband frequency component and a limited maximum acceleration due to shaking table performance. The motions had never been generated by the conventional method.
Introduction Uchide and Ide [SSA Spring Meeting, 2009] proposed a new framework for studying the scaling and overall nature of earthquake rupture growth in terms of cumulative moment functions. For better understanding of rupture growth processes, spatiotemporally local processes are also important. The nature of high-frequency (HF) radiation has been investigated for some time, but its role in the earthquake rupture process is still unclear. A wavelet analysis reveals that the HF radiation (e.g., 4 - 32 Hz) of the 2004 Parkfield earthquake is peaky, which implies that the sources of the HF radiation are isolated in space and time. We experiment with applying a matched filter analysis using small template events occurring near the target event rupture area to test whether it can reveal the HF radiation sources for a regular large earthquake. Method We design a matched filter for multiple components and ...
This paper describes a technique for implementing the ultrasonic inside diameter (ID) creeping wave technique for detection and sizing ID connected defects using a phased array ultrasonic system. The technique uses multiple focal laws to produce the examination modes. The first focal law is designed to create a shear wave nominally at the critical angle for mode conversion to a longitudinal wave at the ID of a part, thus creating a creeping wave. This focal law is focused at the ID to improve sensitivity. The rest of the laws are designed to create tandem sound paths that progress up a vertical surface directly above the focal point of the creeping wave generation point. When a defect on the inner surface is detected with the creeping wave, the height of the defect can be measured from the response of a set of tandem laws without readjusting the position of the probe. Results from standard one-inch long ...
ObjectiveMusician's focal dystonia is usually considered to be task specific but secondary motor disturbances have been reported also. We carried out a detailed evaluation of the...Full Text Available
BackgroundSeveral proteins are known to be markedly expressed in the brain during cerebral ischemia; however, the changes in protein profiles within the ischemic brain after an ischemic...Full Text Available
Auditory conditioning (associative learning) causes reorganization of the cochleotopic (frequency) maps of the primary auditory cortex (AI) and the inferior colliculus. Focal electric stimulation...Full Text Available
Academy of Neurology and the American Epilepsy Society. Neurology. 2007;69:1991-2007. Rubin DH, Kornblau DH, Conway Jr EE, et al. Neurologic Disorders. In: Marx, JA, ed. Rosen's...
Neutral endopeptidase 24.11 (NEP, CD10) is a cell-surface enzyme expressed by prostatic epithelial cells that cleaves and inactivates neuropeptides implicated in the growth of androgen-independent prostate...Full Text Available
Although ultrasound arrays were exploited in photoacoustic imaging to improve imaging speed, ultrasound-array-based optical-resolution photoacoustic microscopy (OR-PAM) has never been achieved...Full Text Available
The aim of the present study was to identify specific behavioral patterns that contribute to diminished estrus expression in lame cows. Behavioral scan and focal sampling were used to examine...Full Text Available
The longitudinal and transverse dynamics of a heavy ion fusion beam during the drift compression and final focus phase is studied. A lattice design with four time-dependent magnets is described that focuses the entire beam pulse onto a single focal point with the same spot size.
IntroductionAutologous chondrocyte transplantation (ACT) is a routine technique to regenerate focal cartilage lesions. However, patients with osteoarthritis (OA) are lacking an appropriate...Full Text Available
The present work addresses an off-axis Cassegrain optical concentration system. The specific primary collector analyzed, a short focal length parabolic concentrator, is at the University of Florida`s Energy Park. A secondary hyperbolic reflective element was designed to redirect the solar radiation from the primary focal plane to an off-axis target on the polar axis of the primary concentrator. This ground level target will be required for planned experimental work. The analysis was performed using a numerical ray tracing procedure that incorporates both random and systematic errors due to slope and surface irregularities. The optimization process varied secondary element size, curvature, and offset angle, and yielded information required for optimum design. As a single secondary element was found impractical, three elements were designed for use at various time of the year. The numerical analysis predicts that typically 70 to 75 percent of the ...
In the development of the man-made island siting technology of nuclear power plants, assessing the stability of the seawall against large ocean waves and earthquakes is indispensable. Concerning with the seismic stability of the seawall, prediction of the deformation like sliding and settlement of the seawall during earthquake including the armour units in front of the caisson becomes important factor. For this purpose, the authors have developed the two-dimensional DEM-FEM coupled analysis method (SEAWALL-2D) to predict the deformation of the seawall covered with the armour units during earthquake. In this method, movements of the armour units are calculated in DEM analysis part and deformation of the caisson, rubble moundsand seabed and back fill are calculated in FEM analysis part taking the nonlinearity of the soil materials based on the effective stress into account. Numerical simulations of dynamic centrifuge model ...
... Austrian Environment Minister Nikolaus Berlakovich called for such stress tests on Sunday (13 March) to make sure that nuclear power stations were quake-proof following Japan's massive earthquake and tsunami. Austria, a mountainous country rich in geothermal energy, has no NPPs and no plans to develop ...
The Department of Energy is investigating Yucca Mountain, Nevada as a potential site for commercial radioactive waste disposal in a mined geologic repository. One critical aspect of site suitability is the tectonic stability of the repository site. The levels of risk from both actual fault displacements in the repository block and ground shaking from nearby earthquakes are being examined. In particular, it is necessary to determine the expected level of ground shaking at the repository depth for large seismic sources such as nearby large earthquakes or underground nuclear explosions (UNEs). Earthquakes are expected to cause the largest ground motions at the site, however, only underground nuclear explosion data have been obtained at the repository depth level (about 350m below the ground level) to date. In this study we investigate ground motion from Nevada Test Site underground nuclear explosions recorded at Yucca Mountain ...
An understanding of the mechanism of generation of Lg from underground nuclear explosions is essential for seismic monitoring and source discrimination. Near-source scattering of explosion-generated Rg into S appears to be responsible for the low-frequenc...
In order to understand not only the mechanisms of earthquakes, but also the origin of diverse behavior of faults and plate boundaries, one must integrate (1) field studies on faults to understand deep intrafault processes, (2) laboratory work to reproduce those processes and determine mechanical and transport properties of fault zones, (3) theoretical and numerical studies analyzing fault motion, including earthquake generation processes, based on the constitutive properties determined by laboratory studies, and (4) seismological and geodetic studies revealing dynamic fault motion during earthquakes and diverse aseismic fault behavior. Ideally, such integrated studies should be carried out for a selected fault that produced an earthquake with good seismic/geodetic records so the prediction from (1) to (3) can be fully tested with (4), rather than selecting favorite data in the literature. Present ...
A focal plane detector system consisting of a vertical drift chamber, parallel plate avalanche counters, and an ionization chamber with segmented anodes has been installed in the Broad Range Spectrometer at the Holifield Facility at Oak Ridge. The system, which has been designed for use with light-heavy ions with energies ranging from 10 to 25 MeV/amu, has a position resolution of approx. 0.1 mm, a scattering angle resolution of approx. 3 mrad, and a mass resolution of approx. 1/60.
Long cylindrical mirror sections with an 'Alliptical' cross- section and an interfoci distance of approximately 1 m can be produced by means of diamond fly cutting. However, because of the finite tool radius, the generated profile is basically not an ellipse, but an equidistant ellipse or 'Allipse'. By numerical ray tracing analysis two unique conjugated 'A-points' can be found that are optically nearly equivalent with pure elliptical focal points. A reversed modeling procedure is used to predict the optimum machine configuration for producing just the required ellipse sections. Optical figure quality, focal line position and straightness are tested by a simple deflectometer set-up.
We compared the characteristics on thin-section CT images with the histological structure of thirty-four surgically resected peripheral lung lesions 30 mm or less in diameter with a greater than 50% area of GGA on thin-section CT. Pathologically, focal area of GGA corresponded to alveolar replacement growth of tumor or interstitial fibrotic thickening of inflammation. It is considered that determination of the GGA in small peripheral lung lesions on thin-section CT is useful for the diagnosis of early adenocarcinomas. (author)
The risk analysis was carried out in consideration of conditions prevailing at the Kalkar site analogous to the investigations in phase A of DRS (German Reactor Study). Earthquake design loads include the probabilities of upper deviations of the site intensities to be expected. The calculations of dynamic loads for select buildings are made using models and computational methods. Component analyses were performed analogous to DRS for the supports of large components, supports of the roof construction of the reactor building taking into account support reserves due to plastic work capacity, wall disks in steam generator buildings and switchboard plant buildings. (DG).
Background. In multiple myeloma 5 different infiltration patterns can be differentiated: 1. Normal appearance of bone marrow, 2. focal involvement, 3. homogeneous diffuse infiltration, 4. combined diffuse and focal infiltration, 5. 'salt-and pepper' pattern with inhomogeneous bone marrow with interposition of fat islands. Methods. For the fast and total acquisition of all patterns a combination of a T1-weighted spin echo sequence and a fat suppression technique is superior. The focal involvement is clearly demonstrated as areas of high signal intensity on e.g. STIR images. Diffuse involvement can be quantified objectively by calculation of the percentage of signal intensity increase after contrast material injection. MRI is superior to X-ray in focal and diffuse involvement. With ultrafast sequences a 'screening' of the whole red bone marrow as for myeloma infiltration is possible. Prognosis. In ...
Complete text of publication follows. According to the new European regulations (Restrictions of Hazardous Substance Directive), there is an emerging demand for environmental friendly metal treatments instead on formerly used chromate conversion coating technique. The aim of the present investigations was to characterise and compare silicon containing protective thin layers on roughened galvanized steel surfaces (with average roughness of 0.7 microns), using FTIR microscopy and imaging techniques. The silicon containing coatings were produced either by Chemical Vapour Deposition (CVD) or by wet chemical treatment using liquid silane. FTIR techniques offer new possibilities in the characterisations and chemical mapping of differently coated thin films, besides SEM+EDS, AFM, nanoindentation, XPS measurements (P. Nemeth et al., Materials Science Forum, 589 (2008) 433-438). All measurements were carried out by a Varian FTS-7000 spectrometer with a 'Stingray' microscope configuration ...
Present day mammography has not been able to make use of the advantages of digital luminescence radiography because of the limited spatial resolution. The recent development of electromagnetic focusing X-ray tube with effective focal spot sizes from 0.04 to 0.12 mm allows radiographic direct magnification with less geometric blur. It is now possible to combine direct magnification mammography with digital luminescence radiography. By combining high quality storage phosphor screens with an HQ-workstation a spatial resolution of 8 lp/mm is possible for 1.7-fold magnification. For 4-fold spot magnification views spatial resolution can be theoretically increased to approx. 20 lp/mm. One important advantage of digital radiography is the possibility of image-postprocessing. This article presents two sets of standard parameters and three sets of image dependent parameters for better imaging of specific lesions, such as ...
Phase contrast X-ray imaging has been studied intensively using X-rays from synchrotron radiation and micro-focus X-ray tubes. However, these studies have revealed the difficulty of this technique's application to practical medical imaging. We have created a phase contrast imaging technique using a molybdenum X-ray tube with a small focal spot size for mammography. We identified the radiographic conditions in phase contrast magnification mammography with a screen-film system, where edge effect due to phase contrast overcomes geometrical unsharpness caused by the 0.1 mm-focal spot of a molybdenum X-ray tube. The edge enhancement due to phase imaging was observed in an image of a plastic tube, and then geometrical configuration of the X-ray tube, the object and the screen-film system was determined for phase imaging of mammography. In order to investigate a potential for medical application of this method, we conducted evaluation of the images of ...
A new focal plane detector for an Enge split pole spectrograph has been developed which is able to resolve individual elements and isotopes up to the mass 100 region. It consists of a 60 cm long position sensitive parallel plate avalanche counter backed by a large Bragg curve detector. Compared with other position sensitive focal plane counters the new detector system has a very good time resolution (less than 300 ps) and can be operated at much higher counting rates (up to 25 kHz). The intrinsic resolution of the position detector is less than 1 mm. In addition to the energy and the nuclear charge signal obtained from the Bragg curve detector the angle of incidence into the detector can be measured with an accuracy of better than 1/sup 0/. The detector has already been used in a variety of experiments where good timing, counting rate behavior, and excellent mass resolution over a large energy range were essential.
The Chuetsu-oki Earthquake strongly shook the Kashiwazaki-Kariwa Nuclear Power Station with the ground motions exceeding the design values. The incidents include a fire breakout of the Unit 3 transformer, a release of spilled water containing small amount of radioactive materials to the non-radiation control area and subsequently to the environment at Unit 6, and a release of radioactive material from the main turbine condenser through the main stack of Unit 7 due to the delay stooping the turbine gland steam ventilator by the operator in manually, while every unit in operation was safety shutdown in the automatic mode ensuring the three fundamental safety functions of (a) reactivity control, (b) removal of heat from the core and (c) confinement of radioactive materials. Following integrity evaluation and performance testing of the overall plant, seismic safety of buildings, structures, equipment and pipelines on the basis of the basic ...
Following the February 2011 earthquake in Christchurch, New Zealand (NZ), the authors participated in counselling local residents, and debriefing and supervising support teams. Indications were that risk for mental health disorders, including Post-Traumatic Stress Disorder (PTSD), may be elevated in residents, and that this risk may continue for some time. Patients may be de-prioritising their mental health issues when these become normalised throughout the city's population. The authors recommend that primary care patients are assessed using a brief, comprehensive tool (for example, the Case-finding and Help Assessment Tool) that targets many health and behavioural issues identified as increasing in the city following the earthquake. Anxiety and mood disorder symptoms may indicate assessment is appropriate to reduce harm arising from increased risk for PTSD. Concern also is raised for primary health care providers who may have experienced the ...
The design and construction of a Browne-Buechner type round pole face magnetic electron spectrograph is described. The design is based on the first order transfer properties of the bending magnet including the focal surface, dispersion, magnification and resolution. Second order aberrations are compared wit numerical ray tracing results using measured field data to simulate the magnet. The numerical results are also compared with floating wire measurements on the system. Agreement is within one part in 10"4. Data extraction from the instrument is done with an array of copper detectors placed along the focal surface. The spectrograph has been successfully employed in free-electron laser (FEL) experiments for over a year.
Two cases of focal nodular hyperplasia (FNH), in which ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MR) studies detected an atypical hemorrhagic pattern associated with an intrahepatic arterio venous malformation (AVM) around the growths, are presented. In both cases, histology demonstrated a very early regenerative stage and necrotic-hemorrhagic areas within the lesions. In these cases, the analysis of radiological findings, surgical specimens and histology seemed to confirm the pathogenetic hypothesis suggested by Wanless: in normal liver parenchyma, a ``blood steal`` phenomenon due to congenital or acquired intrahepatic AVM could cause ischemic damage, appearing as a hemorrhagic necrotic area, the extent of which depends on the degree of residual portal supply. (orig.)
The Seismic Risk Explorer, an extension for ArcGIS Desktop developed by cedim AG, is a tool for computing the seismic risk, i.e. damage on residential buildings and thereby caused monetary losses for earthquake scenarios. It is based on the research results of the CEDIM (Center for Disaster Management and Risk Reduction Technology) research center, located at the Karlsruhe Institute of Technology (KIT) and the GeoForschungsZentrum (GFZ) in Potsdam. With this software tool seismic scenarios can be simulated for a given magnitude, depths and location. The seismic intensity, the resulting mean damage ratio for residential buildings and the seismic risk, expressed as the monetary loss caused by an earthquake can be computed downscaled to communities, postcode areas or even single buildings. Interested end-users are especially insurance companies, but also public authorities which may use the tool for risk management issues.
An overview of BC Hydro`s review of its overhead transmission system to withstand earthquakes and its program of seismic upgrading, including the upgrading of tower pile foundations in liquefiable soils, was presented. BC Hydro`s system, geologic environment, seismic design criteria, investigations and analysis, treatment and alternatives and a case history of a seismic upgrade of a tall river crossing tower at the Pitt River in the Lower Mainland of B.C. were summarized. It was concluded that the inherent strength of towers, conductors, fittings and insulators was sufficient to withstand earthquakes. The towers most susceptible to slope and soil failure due to seismic activity were tall river crossing towers. It was suggested that soils investigations, seismicity, ground response, liquefaction and stability analyses be carried out at each site. The results of these tests would help to establish system seismic design criteria at each location. ...
Landslides on ancient embankments, burial mounds of Imashiro-zuka and Nishimotome-zuka, induced by historical earthquakes related to the tectonic movement of active fault systems located between northern Osaka and Kobe, are discussed. The geological conditions of the foundation of the mounds, the lithology, stiffness, and the position of the mound relative to the fault systems, contributed to the collapse of the mounds. Obvious interior structures of landslides revealed the inherent deformation process, and provided significant insight into landslide mechanisms. Rapid increasing pore water pressure was necessary to facilitate sliding along the almost horizontal slip surfaces developed in the main part of the landslide bodies on the Imashiro-zuka mound. Liquefaction analysis using both the ...
For a given linac design, the dosimetric characteristics of a photon beam are determined uniquely by the energy and radial distributions of the electron beam striking the x-ray target. However, in the usual commissioning of a beam from measured data, a large number of variables can be independently tuned, making it difficult to derive a unique and self-consistent beam model. For example, the measured dosimetric penumbra in water may be attributed in various proportions to the lateral secondary electron range, the focal spot size and the transmission through the tips of a non-divergent collimator; the head-scatter component in the tails of the transverse profiles may not be easy to resolve from phantom scatter and head leakage; and the head-scatter tails corresponding to a certain extra-focal source model may not agree self-consistently with in-air output factors measured on the central axis. To reduce the number of adjustable variables in beam ...
The results of treatment of 53 cases of pediatric localized Ewing's sarcoma and bone reticulosarcoma were analized. Chemoradiotherapy is a procerdure of choice in bone marrow sarcoma treatment: while overall five-year survival was 28.4#+-#6.2%, it was as high as 64.9% in cases of combined treatment (total focal dose of at least 50 Gy+polychemotherapy). Two cases of osteo- and chondrosarcoma development in exposed bone are described.
Positron emission tomography (PET) and magnetic resonance imaging (MRI) studies were performed on a case of neuro-Behcet's syndrome. In accordance with the clinical signs, FDG PET (using /sup 18/F-labeled 2-F-2'-desoxyglucose) revealed disseminated storage defects in the cerebrum and cerebellum. Focal regions of enhanced signal intensity were demonstrated in the parietal white matter of the cerebrum in T2-weighted images and in the brain stem by MRI. (orig.).
Using an anti-receptor mAb that blocks the attachment of echovirus 7 and related viruses (echoviruses 13, 21, 29 and 33), we have isolated a complementary DNA clone that encodes the human decay-accelerating...Full Text Available
Theoretical and experimental results of investigating a cylindrical heat receiver with secondary reflectors are presented. One important element of solar thermal power plants (STPP) is the heat receiver. Several forms of heat receiver exist; the main form is the heat receiver of cavity form (including cylindrical, rectangular, and cubic heat receivers with a noncircular aperture). The linear dimension of such heat receivers is equal to, or larger than, the theoretical diameter of the concentrator focal spot.
Stability concerns of the Par Pond Dam, an embankment structure in the Savannah River Site complex, resulted in a comprehensive evaluation of the state of its integrity. Specifically, excessive seepage through the embankment, slope failure due to an earthquake event as well as liquefaction potential of the embankment and the foundation are addressed and the potential of failure is evaluated. Lastly, remedial benefits of the addition of a berm structure are also assessed.
Radon concentration measurement in the ground can be used for the prospecting for uranium and earthquake prediction. Some results of radon concentration measurement in the soil are presented here. The moisture condensation at the detector surface can affect on the detection efficiency. Due to this problem we tested a few filter papers on water permeability. The ratio of track densities on solid state nuclear track detector (SSNTD) in the open and the closed diffusion chamber is also determined. (author)
Background. In multiple myeloma 5 different infiltration patterns can be differentiated: 1. Normal appearance of bone marrow, 2. focal involvement, 3. homogeneous diffuse infiltration, 4. combined diffuse and focal infiltration, 5. 'salt-and pepper' pattern with inhomogeneous bone marrow with interposition of fat islands. Methods. For the fast and total acquisition of all patterns a combination of a T1-weighted spin echo sequence and a fat suppression technique is superior. The focal involvement is clearly demonstrated as areas of high signal intensity on e.g. STIR images. Diffuse involvement can be quantified objectively by calculation of the percentage of signal intensity increase after contrast material injection. MRI is superior to X-ray in focal and diffuse involvement. With ultrafast sequences a 'screening' of the whole red bone marrow as for myeloma ...
The role of MRT in the prebiopsy diagnosis of muscular and vascular inflammatory conditions was evaluated prospectively and an optimal method of examination was investigated. 92 patients with a suspected diagnosis of myositis (60 cases) or vasculitis (32 cases) were examined, in each case two extremities were studied using transverse T_1 and T_2 weighted SE sequences and double echo STIR sequences on a 0.5 Tesla (56 patients) or 1.5 Tesla magnet (36 patients; T5/S15 Gyroscan, Philips). The site of the biopsy depended on the MRT findings. In 41 patients the suspected diagnosis was confirmed histologically, in two patients an infective myositis was diagnosed on clinical grounds despite negative histology. MRT demonstrated muscle oedema in 86% of patients. There were negative findings after immuno-suppressive therapy (two patients), in focal myositis (3 out of 4 patients) and in one of 7 patients with untreated vasculitis. Amongst 49 patients in whom the suspected ...
Brain glucose metabolism was evaluated in four patients with acquired immunodeficiency syndrome (AIDS) dementia complex using ["1"8F]fluorodeoxyglucose (FDG) and positron emission tomography (PET) scans at the beginning of therapy with 3'-azido-2',3'-dideoxythymidine (AZT, zidovudine), and later in the course of therapy. In two patients, baseline, large focal cortical abnormalities of glucose utilization were reversed during the course of therapy. In the other two patients, the initial PET study did not reveal pronounced focal alterations, while the post-treatment scans showed markedly increased cortical glucose metabolism. The improved cortical glucose utilization was accompanied in all patients by immunologic and neurologic improvement. PET-FDG studies can detect cortical metabolic abnormalities associated with AIDS dementia complex, and may be used to monitor the metabolic improvement in response to AZT treatment.
Full text: Tumour ablation with radiofrequency (RF) energy is a relatively new procedure for the treatment of focal malignant disease. At our institution this is currently being used in the treatment of certain liver and lung lesions with the patients involved being enrolled in clinical trials. The poster describes the technique used at our institution for the placement of the radiofrequency ablation electrode using CT fluoroscopy. Criteria for patient selection are included. Complications from the procedure are described, as well as follow up appearances and results. Our results from the treatment of primary and secondary lesions in the liver correlate well with published literature. Treatment is still not as successful as surgical resection but there is significantly less morbidity. Where this method may be appropriate is when the patient is not a candidate for surgical resection. The treatment of colorectal metastases in the lung shows early promise as a ...
The PLANCK SURVEYOR is a European Space Agency satellite mission to image the very faint anisotropies in the temperature of the Cosmic Microwave Background (CMB) radiation. Maynooth is actively participating in an international collaboration of scientists involved with the optical design of the High Frequency Instrument (HFI). This paper outlines research which has been undertaken in Maynooth concerned with numerical modelling of the optical characteristics of the multi-frequency array of detectors making up the HFI instrument. In the study the commercial software package ZEMAX was used to model the coupling of the focal plane HFI detectors to the PLANCK telescope. This package is particularly useful in the optical design of PLANCK because of the powerful optimisation features of the software. It is thus possible to readily determine the optimum positioning of the detectors in the focal plane of the telescope. Although the package is based on a ...
To analyze and review the most common focal lesions of the external auditory canal (EAC), describing the computed tomography (CT) findings. The CT images of EAC were reviewed in a series of 167 patients. Abnormal findings were recorded in 13 cases. The CT images were correlated with otoscopic and/or intraoperative findings. There were four cases of osteoma (one located outside the EAC); all of which were treated surgically, as was the one case of exostosis. Six patients presented debris in EAC, coinciding with clinical evidence of external otitis. There were two cholesteatomas derived from EAC, one of them secondary to survery to treat osteoma. On patient was diagnosed as having a basal cell carcinoma of the ear, extending to EAC, but refused to undergo surgery. Five patients presented small triangular laminae of dense bone arising from the upper wall of the EAC which were defined as abnormal variants of the fusion of the temporal squamous epithelium to the ...
Fault analysis is required in addition to the ordinary process of structural analysis (CDP stacking) for the examination of discontinuity in the reflection horizon in question. The fault shape restoration principle is that the reflection point of a reflection wave observed at a certain receiving point is on an ellipse with the shock point and receiving point at its focal points and that the sum of the distances between the reflection point and the focal points is equal to the reflection wave propagation time. The DMO velocity is worked out by calculation using the positive travel time and inverse travel time from the common reflection surface. When the reflection surface is inclined by {theta}, the average interval velocity/cos{theta} is called the DMO velocity. When the reflection surface inclination and the average interval velocities are determined separately in this way, the position of the reflection point may be worked out, and this ...
This report summarizes the work on high field superconducting materials and processes performed at the Materials and Molecular Research Division of the Lawrence Berkeley Laboratory. Two major interrelated focal points characterize this research. One was the decision to restrict the effort to A-15 compounds because of their superior critical temperatures and critical fields. The inherent brittleness of these compounds along with the requirement for a filamentary morphology led to the second focal point: a heavy reliance on a powder approach for the fabrication of superconducting tapes and wires. There have been exceptions to the use of powder techniques where special circumstances such as the nature of a particular alloy system suggested on alternative approach. The quench-age technique described herein is an example of a non-powder approach. Here the niobium-aluminum system is involved and the methodology is based on the fact that in a certain ...
Fuel assemblies in a reactor pressure vessel are disposed in a reactor core shroud. The own weight of the fuel assembly is supported by a reactor core support plate, and is supported, for the horizontal direction, by an upper lattice plate and the reactor core support plate. A support portion for the upper portion of the fuel assembly is disposed above the fuel assembly, and a support portion for the support portion described above is joined to a shroud head by welding. The support portion for the upper portion of the fuel assembly has a network-like portion which absorbs and disperses rising force which exerted on the fuel assembly when the fuel assembly is risen by seismic forces. The rising force exerted on the fuel assembly absorbed by the network-like portion is effectively transferred to the shroud head by the support portion. With such a constitution, rising of the fuel assembly can be prevented against the seismic vibrations having prominent vertical vibration components such ...
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 load coefficient. It was decided regarding earthquakes to discuss strength and toughness of ...
Heating during frictional sliding is a major component of the energy budget of earthquakes and represents a potential weakening mechanism. It is therefore important to investigate how heat dissipates during sliding on simulated faults. We present results from laboratory friction experiments where a halite (NaCl) slider held under constant load is dragged across a coarse substrate. Surface evolution and frictional resistance are recorded. Heat emission at the sliding surface is monitored using an infra-red camera. We demonstrate a link between plastic deformations of halite and enhanced heating characterized by transient localized heat spots. When sand 'gouge' is added to the interface, heating is more diffuse. Importantly, when strong asperities concentrate deformation, significantly more heat is produced locally. In natural faults such regions could be nucleation patches for melt production and hence potentially initiate weakening during ...
Nowadays the safety of Nuclear Power Plants is becoming more and more significant. Therefore consideration of severe accidents shall be included in both design and operating process of Nuclear Power Plants. In particular ground motion forms one of the important natural hazards. For structural analysis both linear-elastic and non-linear methods are specified by the engineering codes for earthquake resistance design. However, time history analysis is required for investigation of non-linear structural behaviour. Moreover, non-linearities are often caused by the presence of damage. This can be detected by means of structural health monitoring and subsequently system identification. In this paper the advantages of both dynamic time history analysis and damage detection by means of wavelet analysis are discussed. First, the non-linear behaviour of a frame structure due to an artificial earthquake motion is analyzed. A comparison to non-time history ...
Canisters with spent nuclear fuel can obviously not be located within deformation zones as this might jeopardise their long term mechanical stability and thereby constitute a potential hazard to the biosphere. Less apparent, but equally important, is the fact that earthquakes trigger reactivation, slip, of structures some distance from their hypocentres due to, among many other factors, stress redistribution. Fault slip across a deposition hole might damage the isolation capacity of the canister and thereby jeopardise the overall integrity of the barrier system. Therefore, the following question might be posed: What is the distance from a deformation zone beyond which a canister can be safely emplaced? This respect distance cannot be readily computed because, unknown future events aside, there are some complicated aspects that need to be addressed e.g. degree of conservatism, scale, our ability to model ice sheets and earthquakes, etc. In this ...
A 200 ft. tall stack, consisting of a concrete chimney with an independent acid proof brick liner built in the 1950`s, serving the Separations facility at the Savannah River Site (SRS), was evaluated for the performance category 3 (PC3) level of Natural Phenomena Hazards (NPH) effects. The inelastic energy absorption capacity of the concrete chimney was considered in the evaluation of the earthquake resistance, in particular, to compute the F{sub {mu}} factor. The calculated value of F{sub {mu}} exceeded 3.0, while the seismic demand for the PC3 level, using an F{sub {mu}} value of 1.5, was found to be less than the capacity of the concrete chimney. The capacity formulation of ACI 307 was modified to incorporate the effect of an after design opening on the tension side. There are considerable uncertainties in determining the earthquake resistance of the independent brick liner. The critical liner section, located at the bottom of the breeching ...
The objective of this project were to investigate the dynamic behavior of peat and to evaluate the influence of that behavior on the dynamic response of peat deposits. During the course of the research, the objectives were expanded to explore the effects of strong earthquake shaking on pile foundations embedded in peat deposits. An experimental investigation was undertaken using samples of a peat deposit typical of many large peat deposits in western Washington. A series of ground response analyses was performed to investigate the seismic response of peat deposits. Three vertical profiles through Mercer Slough were analyzed using both equivalent linear and nonlinear ground response analyses. The analyses showed that the soft nature of the Mercer Slough peat would produce amplification of the long-period components of an earthquake ground motion. Comparison of the equivalent linear and nonlinear ground response analyses showed that the ...
A variable-dispersion electron spectrometer is being installed for use by the Stanford Superconducting Accelerator in conjunction with its Free Electron Laser program. The system has been designed to operate with electron beam energies from 20 MeV to 200 MeV, with a maximum energy resolution of 0.01% FWHM. The maximum energy acceptance is approximately #+-# 5%, as determined by the bending magnet aperture. Resolution is controlled by adjusting the focal conditions at the entrance to a 90 degree bending magnet, while the dispersion is controlled by changing the magnitude and polarity of the field in a quadrupole magnet which immediately follows the bending magnet. 4 refs., 5 figs.
Radiotherapeutic results of the Ewing sarcoma of the long tubular bones in 140 pediatric patients aged 3-16 are analyzed with the respect to different methods of irradiation. Three-field irradiation, the fields being located at 120 deg to one another with daily irradiation of all three fields at a focal dose of 2 Gy, was found superior in treatment of primary neoplasm. It is stressed that the disease termination mainly depends on the efficiency of primary neoplasm treatment, as the neoplasm reccurence generally is followed by metastases. Radiation load is calculated for maximal irradiation area of soft tissues in children.
ARIES Baker-Nunn Schmidt telescope project is converting a Baker-Nunn satellite tracking camera for Astronomical research. Original Baker-Nunn camera produces an extremely large (5X30 degree) curved focal plane at the prime focus for photographic imaging. We present here the re-designing of the camera produces a wide (4 X 4 degree) flat field of view for CCD imaging observations, which have many scientific potentials in Astronomy. Imaging performance of the CCD camera is also estimated.
In an ideal system the surface of the dish is perfectly parabolic (no contour flaws are present), and the sun rays fall on the dish surface parallel to the focal axis (no sun tracking flaws are present). These two conditions are not realizable in practice; in this case, the parabolic dish system is called real system. In this paper a procedure for analysing the flux distribution on the receiver internal surfaces is presented for a cavity receiver with a real parabolic dish collector. First, the theoretical principles are discussed. Then the effect of the inaccuracy in the collector and in the sun tracking on the insolation pattern is described using an example.
Gallium imaging is increasingly being used for the early detection of complications in patients with AIDS. A 26-year-old homosexual man who was HIV antibody positive underwent gallium imaging for investigation of possible Pneumocystis carinii pneumonia. Widespread cutaneous focal uptake was seen, which was subsequently shown to be due to mycobacterium avium-intracellulare (MAI) septicemia. This case demonstrates the importance of whole body imaging rather than imaging target areas only, the utility of gallium imaging in aiding the early detection of clinically unsuspected disease, and shows a new pattern of gallium uptake in disseminated MAI infection.
This paper describes the phenomenology of nuclear explosions and technologies for their detection as relevant to On-Site Inspection (OSI) for a comprehensive test-ban (CTB). Our experience with the US nuclear test program which has been primarily carried out at the Nevada Test Site (NTS) and in the Pacific Ocean. The goals of OSI are to resolve ambiguous events, reduce uncertainty, deter attempts at evasion, and provide responsive and technically competent means of confirming the occurrence of a nuclear explosion should deterrence fail. These goals would include finding evidence of an evasive nuclear explosion or evidence that the event was non-nuclear, such as an earthquake or large chemical explosion.
The various technical aspects of radon concentration measurements in the ground or in the groundwater are reviewed. The emphasis is put on the most convenient techniques particularly suited for in situ monitoring in the field. Some attention is paid to the thoron problem. Historical and most recent findings in the field or earthquake related radon anomalies are presented and briefly discussed. A similar approach is made to rarer volcanic cases that have been documented up to now. A short discussion regarding the various models that intend to provide satisfactory explanations is presented, supported, whenever it is possible, by experimental laboratory results. Finally a glimpse on the possible and future application of the method to hydrogeology is given. (orig.).
Unit one of Daya Bay, China's first nuclear power plant was officially opened in February 1994. The nuclear island has been built by Framatome and is an improved version of the Gravelines 5 and 6, 900MWe Pressurized Water Reactors. Extra seismic protection has been included because of greater earthquake risk. The heat exchanger capacity has also been increased as the sea cooling water can be at 30"oC. The technical specifications and details of the fuel loading are given. The technical assistance, management and training of Chinese personnel are discussed. Two further units may be built if Daya Bay 1 is successful. (UK).
It is important to accurately estimate the effects of strong earthquake motions on the basemat uplift behavior and structural responses for the seismic design of nuclear power plant buildings. In this paper, an analysis model which describes the soil part using the 3 dimensional FEM was proposed to be used when the ground contact ratio is low, and the validity of this model was confirmed. Furthermore, investigations using the model were carried out where the attaching force under the basemat was taken into account, in order to more realistically estimate the basemat uplift behavior. The effects in the case of the building being embedded were also investigated.
It is important to accurately estimate the effects of strong earthquake motions on the basemat uplift behavior and structural responses for the seismic design of nuclear power plant buildings. In this paper, an analysis model which describes the soil part using the 3 dimensional FEM was proposed to be used when the ground contact ratio is low, and the validity of this model was confirmed. Furthermore, investigations using the model were carried out where the attaching force under the basemat was taken into account, in order to more realistically estimate the basemat uplift behavior. The effects in the case of the building being embedded were also investigated.
In this paper a new procedure, addressed as Interpolation Damage Detecting Method (IDDM), is investigated as a possible mean for early detection and location of light damage in a structure struck by an earthquake. Damage is defined in terms of the accuracy of a spline function in interpolating the operational mode shapes (ODS) of the structure. At a certain location a decrease (statistically meaningful) of accuracy, with respect to a reference configuration, points out a localized variation of the operational shapes thus revealing the existence of damage. In this paper, the proposed method is applied to a numerical model of a multistory frame, simulating a damaged condition through a reduction of the story stiffness. Several damage scenarios have been considered and the results indicate the effectiveness of the method to assess and localize damage for the case of concentrated damage and for low to medium levels of noise in the recorded signals. The main advantage ...
The end of 1994, five seismic observation stations were constructed with digital seismograph and 3-component seismometers. In this study, the epicentral distribution around the Kyungsang basin was obtained from one-year earthquake data (1994/12 - 1995/11) and compared with the annual earthquake report of KMA (Korea Meteorological Agency). The geological structure at the middle of the Ulsan fault was also investigated by the electrical resistivity method. The epicenters show high concentration at the Wolsung area. They show a linear alignment and their depths tend to be deeper as they approach to the coast line of the East Sea. These imply that they are probably correlated together. Another remarkable feature on land is the linear epicentral distribution along Jiri mountain to the Kimcheon and Sangju. This line is well coincident with newly recognized lineament. The other is the epicentral distribution at the Straits of Korea and East Sea. Even ...
The dynamic response of thin liquid storage tanks to earthquakes is a very complicated phenomenon, because it can be highly non linear. Among others, one can meet material and geometric non linearities of the tank shell leading eventually to static or dynamic buckling non linear behavior of anchor bolts, contact non-linearities due to the uplift of the tank base and to the unilateral character of the fluid pressure on the shell and high amplitude fluid oscillations. Moreover, linear or non linear soil structure interaction affects considerably the response of the fluid structure system under consideration. In this paper we focus attention on problems related only to the base uplift and anchors plastification. We study a tank similar to the Hualien project tank, but we neglect the soil structure interaction. The studied tank is representative of medium height to radius ratio ratio tanks with relatively thick bottom plate. The contact is simulated via a simple ...
We present an image of the rupture propagation of the 2004 M6.0 Parkfield earthquake using records from a dense network of local strong motion stations. We back-propagate high-frequency waveforms in 3D with a method, similar to reverse time migration, to obtain an estimate of the distribution of radiated high-frequency seismic energy in space and time. The image is forced to be coherent at the known hypocenter location and the quake origin time by applying small static time shifts obtained using waveform cross-correlation. We observe that the Parkfield earthquake radiated a distinct secondary high-frequency phase, which is located about 12.5~km northwest of the hypocenter with an onset of seismic radiation about 5~s after the rupture initiation. The time history of the back-projection suggests a rupture velocity of 2.5~km/s between hypocenter and subevent. The back-projection result is confirmed by inversion of picked arrival times of the ...
Innumerable fissures were formed widely in Hanshin area in Japan by the former southern Hyogo prefectural earthquake occurred on Jan.17, 1995. In this study, as a preliminary investigation, we applied passive type radon detector Pico-Rad (U.S. Packard Instrument Co. Ltd.) with hemispheric plastic cover over them around the fissure along on the bank of two reservoirs to examine whether there is possibility to find fissures using the characteristics of "2"2"2Rn migration. One of the reservoir, Taniyamakami-ike, is located at the north of the Awaji-shima island at a distance of about 4 km from the seismic center of this earthquake. On the whole, "2"2"2Rn exhalation rates were high on a line of 2 m below the edge of the bank and got lower in proportion to the distance from this line. Those top of the bank had middle values among the lines. The mean "2"2"2Rn exhalation rate was 4.7 mBq m"-"2 s"-"1, and in these data we found some singularly high ...
Mate choice copying was mostly described as a strategy employed by females to assess the quality of potential mates, but also males can copy other males? mate choice. An open question in this context is whether and how copying males evaluate sperm competition risk, as mating with a female that has already copulated with another male obviously sets the stage for intense sperm competition (i.e., in species with internal fertilization). Using the livebearing Atlantic molly (Poecilia mexicana) as a model, we asked (a) whether males of that species indeed copy other males? choices, and if they do so, (b) whether copying males strategically adjust their behavior to sperm competition risk. We used an approach where focal males could first choose to associate with a large or a small stimulus femal...
In spite of the improved imaging techniques currently available, mortality for pancreatic cancer is still high, and pancreatics is often diagnosed only in its advanced stages. The authors investigated the value of different imaging techniques - i.e., US, CT, and ERCP - for an early diagnosis, when a more effective (curative?) treatment can be suggested. Fifty-six cases of pancreatic cancer and 36 cases of chronic pancreatitis were evaluated. The results indicate that ERCP, with the help of statistical methods, is superior to US and CT not only in evaluating early neoplastic or inflammatory lesions, but also for their differential diagnosis. In the letter case, ERCP can sometimes be used as a valid alternative to fine-needle aspiration biopsy.
A new kind of receiver-reactor for high-temperature solar furnaces is proposed. The main body of the receiver component is an ellipsoid of revolution with specularly reflecting inner walls. The reactor component, a crucible, is placed at one focal point and the aperture at the other. With this arrangement, substantially all of the incident radiation from the concentrator should reach the reactor directly or after one reflection from the cavity walls. An analysis of the radiative exchange among the surfaces is presented. The analysis provides a tool for a parametric study and optimization of the design. It is found that, in contrast to that of conventional well-insulated cavity receivers, its collection efficiency is not very sensitive to the size of its aperture.
An experimental study and a theoretical simulation were made of stimulated Raman scattering (SRS) conversion into shifted components. It was found that there were optimal values of the pressure and focal distance for conversion into the first 'blue' satellite of the first Stokes component. A study was made of the spatial and temporal dynamics of SRS conversion, which took into account generation of the shifted components. It was demonstrated theoretically and experimentally that the satellite intensity could be enhanced significantly by additional electron-collision excitation of the vibrational levels in the conversion medium or by the application of pairs of pump pulses. The maximum efficiency of conversion to the first 'blue' satellite of the first Stokes component was 10% and the satellite intensity reached one-third of the intensity of the main Stokes line. (nonlinear optical phenomena and devices)
An energy transfer and conversion model for high-temperature solar cavity receivers has been developed using the transport behaviour of solar radiation as described by the spectral radiative exchange factors. A Monte-Carlo ray-tracing method coupled with optical properties was adopted, to predict radiation characteristics of the solar collector system by calculating radiative exchange factors. A cavity receiver with a plano-convexo quartz window was proposed, based upon the directional characteristics of the focal flux and the redistribution effect of the quartz window. Parametric studies on the windowed receiver provided a more uniform flux distribution, higher efficiency and lower loss than the windowless receivers. The predicted results serve as a design reference for the solar receiver...
Two patients who developed large intracranial vessel occlusion after standard radiation therapy for brain tumor are described. This form of vascular occlusion is usually seen in patients who have previously been treated by radiotherapy for intracranial tumor who then develop a relatively acute change in neurologic status. Histology of the lesion mimics accelerated focal arteriosclerosis. The clinical and radiographic manifestations of one case were highly atypical. The vasculopathy became evident shortly after termination of radiation therapy for a fourth ventricular ependymoma, and the angiographic picture stimulated a diffuse arteritis. The second patient was more typical, with clinical symptoms developing 12 years after radiation therapy for an oligodendroglioma. Occlusion of a proximal vessel that had been included in the radiation port was demonstrated radiographically and confirmed by pathologic examination. The clinical, angiographic, and histologic features ...
Two patients who developed large intracranial vessel occlusion after standard radiation therapy for brain tumor are described. This form of vascular occlusion is usually seen in patients who have previously been treated by radiotherapy for intracranial tumor who then develop a relatively acute change in neurologic status. Histology of the lesion mimics accelerated focal arteriosclerosis. The clinical and radiographic manifestations of one case were highly atypical. The vasculopathy became evident shortly after termination of radiation therapy for a fourth ventricular ependymoma, and the angiographic picture stimulated a diffuse arteritis. The second patient was more typical, with clinical symptoms developing 12 years after radiation therapy for an oligodendroglioma. Occlusion of a proximal vessel that had been included in the radiation port was demonstrated radiographically and confirmed by pathologic examination. The clinical, angiographic, and histologic features ...
Purpose: To evaluate a simple method for quantification of focal activity in bone scintigraphy (BS). Material and methods: The gamma camera was calibrated using a phantom. Quantitative bone scintigraphy (QBS) was performed on 11 men recently diagnosed with prostate cancer (PCa), for whom routine BS showed involvement of the skeleton. Following endocrine therapy for 4 to 8 months, a second QBS was performed. Changes in QBS values were then compared to changes in serum levels of prostate-specific antigen (PSA). Results: PSA response indicating regression of PCa was accompanied by a decrease in the QBS value in 8 of the 11 patients. The overall mean error of the QBS values was 15%. conclusion: QBS according to this method is a relatively simple procedure that might contribute to objective evaluation of therapeutic effects in skeletal metastases, although its validity must be tested in a larger clinical material.
Purpose: To evaluate a simple method for quantification of focal activity in bone scintigraphy (BS). Material and methods: The gamma camera was calibrated using a phantom. Quantitative bone scintigraphy (QBS) was performed on 11 men recently diagnosed with prostate cancer (PCa), for whom routine BS showed involvement of the skeleton. Following endocrine therapy for 4 to 8 months, a second QBS was performed. Changes in QBS values were then compared to changes in serum levels of prostate-specific antigen (PSA). Results: PSA response indicating regression of PCa was accompanied by a decrease in the QBS value in 8 of the 11 patients. The overall mean error of the QBS values was 15%. conclusion: QBS according to this method is a relatively simple procedure that might contribute to objective evaluation of therapeutic effects in skeletal metastases, although its validity must be tested in a larger clinical material
A photoacoustic (PA) imaging system based on an ultrasonic Fresnel zone plate (FZP) transducer is developed for the purpose of imaging biological tissue. This FZP transducer has a two-zone negative zone plate piezoelectric material pattern, and an optical fibre is integrated with the transducer on the symmetric axis of the zone plates to deliver laser pulses to the sample. The focal characteristic of the FZP transducer is analysed by theoretical prediction and experimental measurement, and the measured results are in good agreement with the predicted results. The limited-field back-projection deconvolution algorithm combined with the coherence-factor weighting technique is used to reconstruct the optical absorption distribution. The experiments were performed with phantoms and the blood vessels of chicken embryo chorioallantoic membrane. The results demonstrate that PA imaging using the FZP transducer has the ability to image biological tissue and has potential ...
This paper presents the design, development and performance characteristics of a low cost solar steam generating system which incorporates recent design and materials innovations of parabolic dish technology. The concentrator is a deep dish of rather imperfect optics, made of silvered polymer reflectors fitted in the aluminum frame of a satellite communication dish. Conventional cavity receivers tend to be inadequate for this concentrator. Semi-cavity and modified cavity receivers, thermally optimised, with the fuzzy focal image have, therefore, been investigated. Preliminary field measurements and cost, as well as performance analyses of the system, indicate a solar to steam conversion efficiency of 70-80% at 450{sup o}C and a collector system cost of Rs 8000-9000/m{sup 2} (1 US dollar = Rs, 40.0). (author)
The aim of the present investigation was to study the effect of weather and available protection on the behaviour of outdoor-wintered beef cattle (Bos taurus). A herd of 78-85 cattle head was studied during four winter months in the Southwest of Sweden. Protection was offered by coniferous forest situated on and around the 12ha pasture, which we divided into protection categories. During 240h we observed 10 cows and 10 heifers as focal animals (each 3h/month) during day time and adjusted observation times to the altitude of the sun. Close to the animals and at an unprotected spot of the pasture we measured temperature, wind speed and solar radiation and combined these variables to a single measure called Wind Chill Temperature (WCT). During observations the animals were in the forest in 12...
In this paper, we present an analytic framework for investigating expert mathematical learning as the process of building a network of mathematical resources by establishing relationships between different components and properties of mathematical ideas. We then use this framework to analyze the reasoning of ten mathematicians and mathematics graduate students that were asked to read and make sense of an unfamiliar, but accessible, mathematical proof in the domain of geometric topology. We find that experts are more likely to refer to definitions when questioning or explaining some aspect of the focal mathematical idea and more likely to refer to specific examples or instantiations when making sense of an unknown aspect of that idea. However, in general, they employ a variety of types of m...
A wavelength division multiplexer/demultiplexer having optical path lengths between a fiber array and a Fourier transform lens, and between a dispersion grating and the lens equal to the focal length of the lens. The optical path lengths reduce losses due to angular acceptance mismatch in the multiplexer. Close orientation of the fiber array about the optical axis and the use of a holographic dispersion grating reduces other losses in the system. Multi-exposure holographic dispersion gratings enable the multiplexer/demultiplexer for extremely broad-band simultaneous transmission and reflection operation. Individual Bragg plane sets recorded in the grating are dedicated to and operate efficiently on discrete wavelength ranges.
The integration of European energy markets is a key goal of EU energy policy, and has also been the focal point of many scientific studies in recent years. International markets for coal, oil, natural gas and electricity have previously been investigated in order to determine the extent of the respective markets. This study enhances this field of research to bioenergy markets. Price series data and time series econometrics are used to determine whether residential sector wood pellet markets of Austria, Germany and Sweden are integrated. The results of the econometric tests show that the German and Austrian markets can be considered to be integrated, whereas the Swedish market is separate from the other two countries. Although increased internationalization of wood pellet markets is likely to contribute to European price convergence and market integration, this process is far from completed. (author)
Ozone has in recent years been increasingly investigated for its potential use in the control of insect pests of stored cereals. Ozone is a powerful oxidizing agent that can react directly, or via production of reactive oxygen species, with proteins, DNA and double bonds of polyunsaturated fatty acids (PUFA). The aim of the present study was to investigate the mode of action in ozone toxicity using the red flour beetle, Tribolium castaneum (Herbst), as a relevant model. Transcription of focal genes thought to be involved in protection against ozone, and repair of cellular damage caused by ozone exposure, was studied together with the composition of storage lipid fatty acids and membrane phospholipid fatty acids in order to detect lipid peroxidation. Contrary to expectations, transcription ...
Computed Tomography (CT) of the spine was performed on 17 patients with myeloma in order to assess the role of the technique in recognizing and evaluating the extent of the lesions. Myelomatous lesions followed two patterns at CT: first of all, multiple focal lesions, whose density is either solid, liquid, or fatty; second, an extensive pattern involving the spongiosa of the vertebra, including the posterior arch. CT detected more lesions than conventional radiology; furthermore, the extent of the lesions was much better demonstrated by CT. CT should thus be performed: a) in case of pain and/or neurological findings in negative radiological examinations; b) to evaluate the extent of myelomatous lesions (mainly in the spine); c) in solitary myeloma CT may be performed on different bone segments with clinical symptomatology but normal X-ray findings.
A case (female, 39?years of) of thyroid-like nasopharyngeal low-grade papillary adenocarcinoma with a significant spindle cell component is presented. The tumor was located on the posterior nasal septum. The spindle cells displayed nuclear features very much similar to the epithelial component and the two cell types merged imperceptibly. Immunohistochemically, the neoplastic cells (including the spindle cell component) were strongly and diffusely positive for TTF-1, cytokeratins (AE1-3), cytokeratin 19 and vimentin. C-kit immunohistochemistry showed diffuse mild to moderate membranous positivity with focal areas displaying moderate to strong immunoreactivity. EMA was strongly positive in the epithelial component with membranous and cytoplasmic reactivity whereas the spindle cell component ...
A 2-D model has been proposed to investigate the approximate estimation of the natural convection heat loss from modified cavity receiver of without insulation (WOI) and with insulation (WI) at the bottom of the aperture plane in our previous article. In this paper, a 3-D numerical model is presented to investigate the accurate estimation of natural convection heat loss from modified cavity receiver (WOI) of fuzzy focal solar dish concentrator. A comparison of 2-D and 3-D natural convection heat loss from a modified cavity receiver is carried out. A parametric study is carried out to develop separate Nusselt number correlations for 2-D and 3-D geometries of modified cavity receiver for estimation of convective heat loss from the receiver. The results show that the 2-D and 3-D are comparabl...
Readout integrated circuits (ROICs) for focal plane arrays (FPAs) have become increasingly complex to meet the needs of modern infrared systems. BAE Systems has pioneered a number of advanced signal processing architectures for FPA ROICs. Demonstrated signal processing capabilities of BAE Systems FPAs include analog-to-digital conversion, offset subtraction, individual pixel automatic gain compensation, transient noise suppression, on-FPA defect deselection, reconfigurable pixels, spatial neural network processing and subframe noise averaging. BAE Systems FPA advanced signal processing is not just for demonstrations, but is used in many of their deliverable FPAs, improving real system performance.
The authors describe a small doubly reflecting research furnace. Its optical components, a heliostat and a concentrating array of hexagonal-in-plan-form mirrors, focus sunlight at the aperture of a cavity receiver. A perfect paraboloid of revolution would have given higher concentration ratios. But large paraboloids are difficult to make and manipulate. Small hexagons are convenient and can be close packed. Spherical mirrors centered on a sphere simplified construction and were economical. In this note they use a simple model to describe the radial distribution of the normal flux at the focus of such an array. A schematic representation of a cross section of the concentrator mirror array in a plane which includes its axis is shown.
This paper seeks to investigate the liquefaction of clayey soils, a phenomenon that has been the trigger for many natural disasters in the last few decades, including landslides. Research was conducted on artificial clay?sand mixtures and natural clayey soils collected from the sliding surfaces of earthquake-induced landslides. The undrained response of normally consolidated clayey soils to cyclic loading was studied by means of a ring-shear apparatus. For the artificial clay?sand mixtures, it was found that the presence of a small amount of bentonite (?7%) would cause rapid liquefaction, while a further increase in bentonite content (?11%) produced the opposite effect of raising soil resistance to liquefaction by a significant degree. It was demonstrated that the bentonite?sand mixture wa...
Abstract This article discusses the evolution of the public debate in Italy about unemployment over a period of almost ten years (1995-2002) that was particularly crucial for the Italian labour and political systems. From the early 1980s and throughout the 1990s, the country experienced major industrial change, which dramatically restructured its labour landscape. Moreover, this industrial earthquake occurred within internal (a deep political party system re-assessment and the fluctuating importance of unions) and external (European Union-driven state budgetary limits) political constraints that have heavily influenced the debate itself. The analysis of the public policy debates allows the authors of this article to portray the agendas, concepts and strategies introduced and discussed by e...
Very large sparse linear least-squares problems arise in a variety of applications, such as geodetic network adjustments, photogrammetry, earthquake studies, and certain types of finite element analysis. Many of these problems are so large that it is impossible to solve them without using auxiliary storage devices. Some problems are so massive that the storage needed for their solution exceeds the virtual address space of the largest machines. A method for solving such problems on a typical (large) computer is described, and the results of some experiments illustrating the effectiveness of this approach are provided. The method includes an automatic partitioning scheme that is essential to the efficient management of the data on auxiliary files. 8 figures, 2 tables
Post-tensioned (PT) self-centering moment frames have been developed as an alternative to typical moment-resisting frames (MRFs) for earthquake resistance. When a PT frame deforms laterally, gaps between the beams and columns open. However, the gaps are constrained by the columns and the slab in a real PT self-centering building frame. This paper presents a methodology for evaluating the column restraint and beam compression force based on the column deformation and gap openings at all stories. The method is verified by cyclic tests of a full-scale, two-bay by one-story PT frame. Moreover, a sliding slab is proposed to minimize restraints on the expansion of the PT frame. Shaking table tests were conducted on a reduced-scale, two-by-two bay one-story specimen, which comprises one PT frame ...
This paper introduces the method of seismic stability analysis for the increase of fuel storage capacity of wet storage stacks by one or two more stack floor at Wolsung Nuclear Unit 2,3,4, which had been originally licensed assuming 16 tray stack-o-storage. As a basic procedure, tipping and sliding stability of the structure is checked at first thru seismic analysis and the resultant load from dynamic analysis is applied for static stress analysis, and the result of which is reviewed for compatability with applicable standard. As a result, sliding and overturning are not expected under design basis earthquakes for increased storage cases of 17 tray and 18 tray stacks. And it is anticipated the result of stress analysis will be acceptable.
This paper introduces the method of seismic stability analysis for the increase of fuel storage capacity of wet storage stacks by one or two more stack floor at Wolsung Nuclear Unit 2,3,4, which had been originally licensed assuming 16 tray stack-o-storage. As a basic procedure, tipping and sliding stability of the structure is checked at first thru seismic analysis and the resultant load from dynamic analysis is applied for static stress analysis, and the result of which is reviewed for compatability with applicable standard. As a result, sliding and overturning are not expected under design basis earthquakes for increased storage cases of 17 tray and 18 tray stacks. And it is anticipated the result of stress analysis will be acceptable.
BC Hydro has been assessing and upgrading its facilities and implementing response alternatives to potential damage resulting from a major earthquake. This paper reviews the utility`s seismic evaluation of its overhead transmission system, focusing on the Lower Mainland area where most of the tall critical river-crossing towers are located. The paper gives an overview of the geologic environment of the Lower Mainland and outlines the criteria used for assessing existing structures for their ability to withstand design seismic loads. It then describes the investigation and analysis methods used in the assessment, including geotechnical field tests, ground response analysis, determination of soil liquefaction potential, and dynamic analysis of structures and piles. Options for seismic upgrades are discussed and illustrated by the case of the Pitt River crossing, where tower foundations were reinforced with steel pipe piles.
The aim of the risk assessment consists of a comparative security evaluation for the SNR-300 and the PWR Biblis B. The failure analysis focusses on the reactor core; in addition, possible fission product release from the spent fuel pits is examined. By reliability analyses, the frequency of events leading to incidents is determined together with the probability of core destruction. In the accident analysis, the kind and frequency of failure of the activity barriers, i.e., primary system (reactorvessel) and inner and outer containment are investigated for the various incident sequences. The radionuclide release into the environment is classified into five different release categories. Besides internal failures, external causes (especially earthquakes and plane crashes) are considered under the aspect of their risk contribution. (RF).
In the past decade, considerable progress has been made on reducing the seismic response of structures through seismic isolation. Application of seismic-isolation techniques to nuclear power facilities is currently being investigated. This paper presents an analysis of the effect of long period motions on a seismic-isolated nuclear structure. Preliminary analysis indicates that long-period earthquake motions increase structural accelerations and relative displacements between the upper and lower mats. Relative displacement between the mats can be represented by spectral displacement at the frequency of the structure, and can be effectively reduced by increasing viscous damping in the isolator. The isolated structure behaves as a system with one degree of freedom. Future analysis of seismic effects on seismic-isolated structures should include the linear and nonlinear effects of soil-structure interactions. 3 refs., 12 figs., 3 tabs.
More than sixty base-isolated buildings have been built in Japan. A number of base-isolation systems were considered in our research, which was intended to establish the effectiveness of base-isolation systems. We conducted research on silicone rubber bearings. Generally, silicone rubber is durable and its characteristics are not dependent on the temperature within the relevant design range. The first part of the report covers material and elements testing. After the bearings were installed in the building, we performed forced vibration tests in both the horizontal and vertical directions. These test results form the next section. After several experiments, we carried out earthquake observations. We report on the effectiveness of the system in reducing response acceleration during a small displacement. This system was installed in the building in March 1992
Earth degassing specifically of carbon dioxide CO2 is of increasing interest with respect to the global carbon budget, related climate effects, earthquake and volcano eruption mechanisms, as well as plant physiological reactions in gas-rich environments. Investigations in all of these disciplines require the detection of surface CO2 degassing structures and quantification of their emissions. We introduce minimal thermal change detection based on infrared imaging as a new remote sensing tool for the detection of earth surface thermal anomalies suiting among others to discover earth degassing locations of any origin. The method allows for seamless areal search and monitoring of degassing structures in any terrain. As proof of concept infrared imaging measurements were performed at the Bossol...
The research and development of a new type of high damping rubber damper for high rise buildings/structures to mitigate earthquake or wind-induced structural response is described in this paper. The static tests were carried out to investigate restoring force characteristics using scale model of high damping rubber damper. The repetitive tests and the temperature dependency tests were carried out to investigate variance of performance of energy absorption. It is confirmed that the damping force characteristics of the damper can be considered as that of linear viscous damping and the damper sufficiently dissipates energy for vibrations of mm order to that of generating 200% shear strain. The design methods, based on assuming linear viscous damping for the damper, has been developed. The designed values such as stiffness and damping coefficient of the damper agree well with the experimental results. (author)
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.).
Thermodynamic parameters for prediction of RNA duplex stability are reported. One parameter for duplex initiation and 10 parameters for helix propagation are derived from enthalpy and free-energy changes...Full Text Available
To analyze the enhancement patterns and morphology of peripheral cholangiocar-cinomas (CCs), as seen on three-phase helical CT. Three-phase helical CT scans of 25 cases of 24 patients with pathologically-proven CCs were retrospectively reviewed. After intravenous administration of contrast media, scans of the hepatic arterial phase (HAP) were obtained at 30 seconds, of the portal venous phase (PVP) at 70 seconds, and of the delayed phase (DP) at 3 minutes. Linear, dense, marginal enhancement was seen in 17 CCs (68%), mainly on HAP images (64%) while thick, band-like, peripheral enhancement was seen in 18 (72%), on either PVP (52%) or DP (44%). Internal enhancement was observed in 23 CCs (92%) on PVP (68%) and/or DP (88%), and 19 CCs (76%) among them showed incomplete enhancement of stippled and/or septated patterns. Most (76%) were seen throughout all three phases to be hypoattenuating, as compared to the surrounding parenchyma. On HAP, wedge-shaped parenchymal enhancement was ...
Purpose: Evaluation of the diagnostic efficacy and cost-benefit of contrast enhanced CT (CT) and MRI pre- and post-SPIO-particles in focal hepatic disease with consideration of therapeutic outcome. Results: In 34/52 (65.4%) of the cases the correct diagnosis was primarily stated by CT (sensitivity [se.] 85.2%, specificity [sp.] 44.0%). In additional 10/52 of the cases unenhanced MRI (se. 91.4%, sp. 75.0%) enabled correct diagnoses, and in another 6 cases the diagnosis was established only by SPIO-MRI (se. 100%, sp. 86.7%). Considering the possible therapeutic recommendation arising from each modality, CT would have induced needless therapy costs of 191,042 DM, unenhanced MRI of 171,035 DM, and SPIO-MRI of 7,311 DM. In comparison to the real therapy costs of 221,873 DM, this would have corresponded to an unnecessary increase of therapy costs of 86.1%, 77.1%, and 3.3%, respectively. In two cases (91 hemangioma, 1 regenerative nodule) all modalities failed, causing ...
A unique beam of pulsed electrons has been developed using the 19-MeV, 700-kA Hermes-III accelerator. The extended planar-anode diode is used to extract at large radius an annular electron beam from the accelerator and inject the resulting beam at small angle into a low-pressure gas cell, where the beam is rapidly charge neutralized and almost current neutralized. Under these conditions, the beam propagates nearly ballistically to a focus downstream of injection, where objects can be placed for irradiation and study. For a focal length of 78 cm, measurements with a segmented calorimeter show that this configuration can deliver an energy deposition of 200 J/g [20 Mrad] over a useful area of 70 cm{sup 2} and a 4-cm depth in graphite in 25 ns. Increasing the injection angle by reducing the AK gap permits higher doses over smaller areas to be achieved. Such beams are of interest for the study of material property changes from short-pulse high-energy depositions and for ...
Supplemental criticality safety analysis of a pool type storage for TRIGA spent fuel at 'Jozef Stefan' Institute in Ljubljana, Slovenia, is presented. Previous results (Ravnik, M, Glumac, B., 1996) have shown that subcriticality is not guaranteed for some postulated accidents. To mitigate this deficiency, a study was made about replacing a certain number of fuel elements in the rack with absorber rods (Glumac, B., Ravnik, M., Logar, M., 1997) to lower the supercriticality probability, when the pitch is decreased to contact (as a consequence of a severe earthquake) in a square arrangement. The criticality analysis for the hexagonal contact pitch is presented in this paper, following the same scenario as outlined above. The Monte Carlo computer code MCNP4B with ENDF-B/VI library and detailed three dimensional geometry was used. First, the analysis about the influence of the number of triangular fuel piles on the bottom that could appear, if the fuel rack, made of ...
The Eagle Flat basin, an intermontane basin in Trans-Pecos Texas, is being considered as a possible site for the Texas repository of low-level radioactive wastes. Intermontane basins and associated normal faults formed in response to Basin and Range tectonism that began about 24 Ma ago. The most active late Tertiary and Quaternary faults occur within the Hueco Bolson (HB) and the Salt Basin/Salt Flat/Lobo Valley, west and east, respectively, of the proposed repository. Several faults of the southeast HB which are within 50 km of the site, displace middle Pleistocene deposits 10 to 24 m. The most recent surface rupture in the southeast HB probably occurred on the Amargosa fault during the Holocene. Upper Pleistocene deposits are offset 2.5 to 4.5 m, and middle Pleistocene deposits are displaced 24 m. Fault scarps within 50 km east of the proposed repository are associated with faults bounding the Salt Basin/Salt Flat/Lobo Valley. In the southern Salt Basin and northern Salt Flat, faults ...
The International Atomic Energy Agency has initiated a co-ordinated research programme on implementation of base-isolation for nuclear structures. This paper discusses two areas relevant to modelling elastomeric base-isolators. These are the use of simplified models to predict the response of isolated structures to earthquake inputs and finite element analysis for calculating the stress distributions within the isolators. In the former, a curvilinear hysteretic model of the high damping natural rubber able to accommodate the stiffening of the rubber at large shear deflections is presented. Its predictions of structural accelerations and bearing displacement produced by design earthquakes and those above the design level are compared with those using a linear spring and dashpot model. A comparison has been made between two finite element analyses using MARC and ABAQUS of the force-deformation behaviour of a single disc of rubber bonded on both ...
In January 1994, a 6.7 magnitude earthquake in southern California ruptured a pipeline releasing approximately 4,200 barrels of blended San Joaquin Valley crude oil. A smaller volume entered the Santa Clara River and flowed 25 km downstream to an emergency containment dam. Ruptured water mains and chlorinated discharges from a damaged sewage treatment plant also affected water quality in the river. Quantitative injury assessment studies were initiated within days of the spill and included water/sediment chemistry, benthic macroinvertebrate community analyses and aquatic toxicity tests. Water quality values for TPH, BTEX, and chlorine ranged from nondetectable to 78 mg/l (TPH), nondetectable to 5.4 microg/l (total BTEX constituents) and nondetectable to 600 microg/l (residual chlorine) within 72 hours of the spill. Ammonia concentrations ranged from nondetectable to 12.1 mg/l within 10 days of the spill. Hydrocarbon concentrations in sediments ranged from ...
We compiled the results of the source analysis obtained under the collaboration research. Recent construction scheme for source modeling adopted in Japan is described, and strong-motion prediction is performed assuming the scenario earthquakes occurring in the Ulsan fault system, Korea. Finally Qs values beneath the Korean inland crust are estimated using strong-motion records in Korea from the 2005 Off West Fukuoka earthquake (M7.0). Probabilistic seismic hazard for four NPP sites in Korea are evaluated, in which the site specific attenuation equations with Index SA developed for NPP sites are adopted. Furthermore, the uniform hazard spectra for the four NPP sites in Korea are obtained by conducting the PSHA by using the attenuation equations with the index of response spectra and seismic source model cases with maximum weights. The supporting tools for seismic response analysis, the evaluation tool for evaluating annual probability of ...
We attempt to image the rupture propagation of the 2004 M6.0 Parkfield earthquake by analyzing records from the USGS Parkfield seismic array (UPSAR) and other strong-motion stations. The UPSAR array consists of 12 stations distributed over about one square kilometer at a distance of 10~km from the San Andreas fault near Parkfield, California. We employ a method that uses reverse time migration to stack the seismograms at back-projected locations along the fault. We use waveform cross-correlation to align the initial P-wave arrivals and correct for small static time shifts in the records. This forces a coherent image at the hypocenter at the quake origin time. Initial results at later time steps show some evidence of the expected rupture propagation to the north. However, the resolution of the back-projection is limited by the small aperture of the UPSAR array. Records from other strong-motion stations can improve the theoretical resolution kernels but are less ...
The staging of patients with multiple myeloma demands sensitive imaging methods for the assessment of the skeletal system. MRI allows for direct visualization of the bone marrow which exhibits five different infiltration patterns in multiple myeloma: 1. normal appearance of the bone marrow, 2. focal involvement, 3. homogeneous diffuse infiltration, 4. combined diffuse and focal infiltration, 5. ''salt and pepper'' pattern with inhomogeneous bone marrow signals due to multiple fat islands. The combination of T1w-SE and STIR sequences is best suited for detecting all infiltration patterns and for the differential diagnoses e. g. hemangiomas. With parallel imaging in MRI, acquisition times can be markedly reduced and whole-body screening of the bone marrow can be achieved within 30 min. MRI is superior to radiography for the detection of focal as well as diffuse infiltration. Multidetector ...
When multiple integrals are approximately evaluated using Korobov cubature formulas, it is necessary to introduce a parameter characterizing the uniform distribution of the grid nodes. A new parameter for Korobov parallelepipedal grids is proposed, and an algorithm for its computation is described.
A method has been developed to predict the effects of mutations in the p53 cancer suppressor gene. The new method uses novel parameters combined with previously established parameters. The most important...Full Text Available
The interaction of intense, sub-picosecond laser pulses with solid targets produces intense picosecond x-ray pulses. With focused laser pulses of several 10 {sup 18} W/cm{sup 2}, He-like and H-like line radiation from targets such as aluminum and silicon has been produced. The energy conversion efficiency from the laser pulse energy to the 1--2 keV line x-rays is nearly one percent. The duration of the line x-ray radiation is of the order of ten picoseconds, although this may be an upper estimate because of the temporal resolution of the x-ray streak camera. The spatial extent of the x-ray source region is only slightly larger than the laser focal spot, or about 10 {mu}m in diameter. With these characteristics, such x-ray sources emit an intensity of nearly 10{sup 14} W/cm{sup 2}. Experiments and modeling which led to the above conclusions will be discussed.
Ultraviolet light can be used to immobilize biomolecules onto thiol reactive surfaces in order to, e.g., make biosensors. The mechanism involves light-induced formation of free, reactive thiol groups in disulphide containing molecules. This technology allows for the creation of arrays of biomolecules with a high degree of reproducibility, circumventing the need for often expensive nano/micro-dispensing technologies. The ultimate size of the immobilized spots is defined by the focal area of the UV beam. Light-induced immobilization has the added benefit that the immobilized molecules will be spatially oriented and covalently bound to the surface. In this paper, we demonstrate the utility of a sensor array created with the new sensor technology when integrated into a microfluidic system. Protein arrays made using light-induced immobilization showed successful antigen/antibody binding in a flow cell allowing the visualisation of real time binding and enzyme activity. ...
To determine the presence, prevalence, and clinical importance of /sup 99m/Tc pertechnetate uterine uptake, this retrospective analysis of 71 Meckel's scans was undertaken. Specifically, each study was evaluated for the presence of a focal accumulation of radiotracer cephalad to the bladder. Patients received an intravenous dose of 150 microCi/kg of /sup 99m/Tc pertechnetate. Each study consisted of 15 one minute anterior serial gamma camera images, and a 15, 30, and 60 minute anterior, right lateral and posterior scintiscan. Menstrual histories were obtained from all patients except two. No males (33/33), nor premenstrual (13/13), menopausal (4/4) or posthysterectomy (2/2) patients revealed a uterine blush. Eleven of 15 patients (73%) with regular menses demonstrated a uterine blush. They were in the menstrual or secretory phases of their cycle. Four demonstrated no uterine uptake, had regular periods, but were in the proliferative phase of their cycle. ...
Studying the structure of nanoparticles as a function of their size requires a correlation between the image and the diffraction pattern of single nanoparticles. Nanobeam diffraction technique is generally used but requires long and tedious TEM investigations, particularly when nanoparticles are randomly oriented on an amorphous substrate. We bring a new development to this structural study by controlling the nanoprobe of the Bright and Dark Field STEM (BF/DF STEM) modes of the TEM. The particularity of our experiment is to make the STEM nanoprobe parallel (probe size 1 nm and convergence angle <1 mrad) using a fine tuning of the focal lengths of the microscope illumination lenses. The accurate control of the beam position offered by this technique allowed us to obtain diffraction patterns of many single nanoparticles selected in the digital STEM image. By means of this technique, we demonstrate size effects on the order-disorder transition temperature in ...
Studying the structure of nanoparticles as a function of their size requires a correlation between the image and the diffraction pattern of single nanoparticles. Nanobeam diffraction technique is generally used but requires long and tedious TEM investigations, particularly when nanoparticles are randomly oriented on an amorphous substrate. We bring a new development to this structural study by controlling the nanoprobe of the Bright and Dark Field STEM (BF/DF STEM) modes of the TEM. The particularity of our experiment is to make the STEM nanoprobe parallel (probe size 1 nm and convergence angle <1 mrad) using a fine tuning of the focal lengths of the microscope illumination lenses. The accurate control of the beam position offered by this technique allowed us to obtain diffraction patterns of many single nanoparticles selected in the digital STEM image. By means of this technique, we demonstrate size effects on the order-disorder transition temperature in CoPt ...
We performed histological examination of 69 samples of Acropora sp. manifesting different types of tissue loss (Acropora White Syndrome-AWS) from Hawaii, Johnston Atoll and American Samoa between 2002 and 2006. Gross lesions of tissue loss were observed and classified as diffuse acute, diffuse subacute, and focal to multifocal acute to subacute. Corals with acute tissue loss manifested microscopic evidence of necrosis sometimes associated with ciliates, helminths, fungi, algae, sponges, or cyanobacteria whereas those with subacute tissue loss manifested mainly wound repair. Gross lesions of AWS have multiple different changes at the microscopic level some of which involve various microorganisms and metazoa. Elucidating this disease will require, among other things, monitoring lesions over time to determine the pathogenesis of AWS and the potential role of tissue-associated microorganisms in the genesis of tissue loss. Attempts to experimentally induce AWS should ...
Multi-beamlet focusing of an intense negative ion beam has been performed using the beamlet steering by the aperture displacement. The apertures of the grounded grid were displaced as all beamlets of 270 (18 x 15) in the area of 25 cm x 26 cm would be steered to a common point (a focal point) in both the two-stage and the single-stage accelerators. The multi-beamlets were successfully focused and the e-folding half width of 10 cm was achieved 11.2 m downstream from the ion source in both the accelerators. The corresponding gross divergence angle is 9 mrad. The negative ion beamlets are deflected by the magnetic field for the electron deflection at the extraction grid and the deflection direction oppositely changes line by line, resulting in the beam split in the deflection direction. This beamlet deflection was well compensated also using the beamlet steering by the aperture displacement of the grounded grid. The beam acceleration properties related with the beam ...
Fourteen patients with cervical hip fractures were treated with internal fixation using titanium screws. The femoral head vitality was evaluated with "9"9Tc"m-MDP scintigraphy and scintimetry within 2 weeks postoperatively and by serial low field magnetic resonance imaging (MR). Two patients with reduced radionuclide uptake (femoral head ratio =# 1.0), MR revealed a focal decrease of the signal intensity in the femoral head or neck at 2, 3 and 7 months after fracture, respectively. The radiographs in one of these patients were normal at 7 months after fracture. The second one showed signs of necrosis at 16 months and the last one developed delayed/non-union. With a non-ferromagnetic osteosynthesis the healing course after femoral neck fracture can be studied with low field MR equipment without disturbing artifacts. The time period between ischaemia and definite abnormalities on MR may embrace several months. (orig.).
We present a new photonic technology and demonstrate that it allows for precise immobilisation of biomolecules to sensor surfaces. The technology secures spatially controlled molecular immobilisation since immobilisation of each molecule to a support surface can be limited to the focal point of the ultraviolet (UV) beam, as small as a few micrometers. We can immobilise molecules according to any pattern, from classical microarrays to diffraction patterns creating unique watermarking safety patterns. Given that suitable protein markers exists for all relevant diseases it is entirely feasible to test for a range of disease indicators (antigens and other markers) in a single test. Few micrometer spotsize allows for a virtually unlimited number of protein spots in a multipotent microarray. This new technology produces radically new photonics based microarray sensing technology and watermarking and has clear potential for biomedical, bioelectronic, surface chemistry, ...
We report a patient who developed occlusion of the intracranial major arteries induced by radiation therapy for craniopharyngioma. The patient, a 9-year-old boy, presented with deterioration of vision, nausea and vomiting. He underwent a right ventriculo-peritoneal shunt operation, and the tumor was partially removed. Postoperatively, he received focal radiation therapy with total of 60 Gy. Preoperative cerebral angiography, cerebral vessels had no sigh of occlusive lesion or stenosis. One year after irradiation, he started to have repeated cerebral ischemic attacks. But no regrowth of the tumor was detected on CT scans. Two years and 8 months after irradiation, he suddenly had right hemiparesis. Cerebral angiography revealed severe stenosis of the right anterior cerebral artery (precommunicating segment), middle cerebral artery (horizontal portion) and terminal portion of the right carotid artery. Left carotid angiography showed complete occlusion of the terminal ...
We report a patient who developed occlusion of the intracranial major arteries induced by radiation therapy for craniopharyngioma. The patient, a 9-year-old boy, presented with deterioration of vision, nausea and vomiting. He underwent a right ventriculo-peritoneal shunt operation, and the tumor was partially removed. Postoperatively, he received focal radiation therapy with total of 60 Gy. Preoperative cerebral angiography, cerebral vessels had no sigh of occlusive lesion or stenosis. One year after irradiation, he started to have repeated cerebral ischemic attacks. But no regrowth of the tumor was detected on CT scans. Two years and 8 months after irradiation, he suddenly had right hemiparesis. Cerebral angiography revealed severe stenosis of the right anterior cerebral artery (precommunicating segment), middle cerebral artery (horizontal portion) and terminal portion of the right carotid artery. Left carotid angiography showed complete occlusion of the terminal ...
SommarioScopo Valutare limpatto clinico negli anni dellecografia intraoperatoria (IOUS) nella identificazione delle metastasi epatiche rispetto alle altre metodiche di imaging. Materiali e metodi risultati delle ecografie intraoperatorie effettuate per lidentificazione delle metastasi epatiche in un periodo compreso tra gli anni 2000 e 2006 sono stati retrospettivamente revisionati e comparati con le metodiche di imaging preoperatorio: Ecografia (US), Tomografia Computerizzata (TC) e/o Risonanza Magnetica (RM). Tutti i casi sono stati patologicamente provati. Sono stati calcolati per anno i casi discordanti in termini di presenza/assenza di lesione focale epatica. Il confronto statistico e stato effettuato con il test di McNemar. Un valore del p<0,05 e stato considerato statisticamente sig...
Aim: Today, MRI is an integral part of the presurgical evaluation of patients suffering from partial epilepsy. These patients frequently show focal morphological abnormalities with potential epileptogenic character and surgical resection of these lesions is associated with superior postsurgical outcome as to seizure frequency. Apart from easily detectable defects, such as post-traumatic lesions or cerebral infarction, as wide variety of mainly small abnormalities can be detected using MRI. Methods: In this study, 484 patients suffering from partial epilepsy of temporal or frontal onset were evaluated for the incidence of different lesions in this population. Results: All lesions found were included without evaluating their potential epileptogenicity, which remains to be proven using other procedures (EEG, SPECT, PET, etc.). Involvement of the hippocampal formation was a major finding in temporal lobe epilepsy, which could be detected as sclerosis (T2w-images), ...
We describe the flight performance of the cryogenic system of the infrared astronomical satellite AKARI, which was successfully launched on 2006 February 21 (UT). AKARI carries a 68.5 cm telescope together with two focal plane instruments, Infrared Cameras (IRC) and Far Infrared Surveyor (FIS), all of which are cooled down to cryogenic temperature to achieve superior sensitivity. The AKARI cryogenic system is a unique hybrid system, which consists of cryogen (liquid helium) and mechanical coolers (2-stage Stirling coolers). With the help of the mechanical coolers, 179 L (26.0 kg) of super-fluid liquid helium can keep the instruments cryogenically cooled for more than 500 days. The on-orbit performance of the AKARI cryogenics is consistent with the design and pre-flight test, and the boil-off gas flow rate is as small as 0.32 mg/s. We observed the increase of the major axis of the AKARI orbit, which can be explained by the thrust due to thermal pressure of vented ...
The Defense TRU Waste Program (DTWP) is the focal point for the Department of Energy in national planning, integration, operation, and technical development for TRU waste management. The scope of this program extends from the point of TRU waste generation through delivery to a permanent repository. The TRU program maintains a close interface with repository development to ensure program compatibility and coordination. The defense TRU program does not directly address commercial activities that generate TRU waste. Instead, it is concerned with providing alternatives to manage existing and future defense TRU wastes. The FY 87 Program Plan is consistent with the Defense TRU Waste Program goals and objectives stated in the Defense Transuranic Waste Program Strategy Document, January 1984. The roles of participants, the responsibilities and authorities for Operations, and Research Development (R D), the organizational interfaces and communication channels for R D and ...
Thirty-six patients with acquired immunodeficiency syndrome (AIDS), who were febrile but without localizing signs, underwent indium-111 leukocyte scintigraphy 24 hours after injection of labeled white blood cells (WBCs) and were restudied 48 hours after injection of gallium-67 citrate. Fifty-six abnormalities were identified as possible sources of the fever; 27 were confirmed with biopsy. Of these 27, 15 were identified only on In-111 WBC scans (including colitis, sinusitis, and focal bacterial pneumonia); six, only on Ga-67 scans (predominantly Pneumocystis carinii pneumonia and lymphadenopathy); and six, on both studies (predominantly pulmonary lesions). In-111 WBC scanning revealed 21 of 27 abnormalities (78%) and gallium scanning, 12 of 27 (44%). If only one scintigraphic study has been performed, particularly with Ga-67, a significant number of lesions would not have been detected. The authors believe radionuclide evaluation of the febrile AIDS patient without ...
The present invention concerns a device for peeling off activated concretes in processing for discarding a reactor of a nuclear reactor facility. The device comprises a gyrotron for generation microwaves, an irradiator for irradiating output microwaves, a reflection mirror for reflecting and converging the microwaves and irradiating them to a material to be irradiated and a first rotating means for rotating the irradiator and the reflection mirror in parallel with the axis of the gyrotron while maintaining the positional relation between the irradiator and the reflection mirror. When the position of the microwaves irradiated on concrete walls are moved in a circumferential direction and the central axes of the rotational axis and the material to be irradiated are aligned, then the intensity of the irradiation of the microwaves at each of the irradiation points can be maintained constant without changing the focal distance of the reflected microwaves thereby ...
Computed tomography (CT) of the thorax shows early promise of important diagnostic advances. We believe that CT often provides information superior to that provided by standard roentgenographic techniques, is capable of significantly influencing patient management, and in selected instances, offers unique information not available by other methods. Computed tomography permits the imaging of mediastinal structures not possible with conventional roentgenographic methods and can diagnose with certainty benign mediastinal conditions such as pericardial cysts and focal or diffuse accumulations of fat. It is ideal for detecting pleural abnormalities and for displaying underlying parenchymal disease in patients with complex pleuroparenchymal shadows on conventional films. Pulmonary metastases unseen on the plain chest film can be detected with greater sensitivity than by any other method. Future applications of CT include the staging of mediastinal lymph nodes in ...
Computed tomography (CT) of the thorax shows early promise of important diagnostic advances. We believe that CT often provides information superior to that provided by standard roentgenographic techniques, is capable of significantly influencing patient management, and in selected instances, offers unique information not available by other methods. Computed tomography permits the imaging of mediastinal structures not possible with conventional roentgenographic methods and can diagnose with certainty benign mediastinal conditions such as pericardial cysts and focal or diffuse accumulations of fat. It is ideal for detecting pleural abnormalities and for displaying underlying parenchymal disease in patients with complex pleuroparenchymal shadows on conventional films. Pulmonary metastases unseen on the plain chest film can be detected with greater sensitivity than by any other method. Future applications of CT include the staging of mediastinal lymph nodes in ...
A paraboloidal dish solar thermal power plant produces electrical energy by a two-step conversion process. The collector subsystem is composed of a two-axis tracking paraboloidal concentrator and a cavity receiver. The concentrator focuses intercepted sunlight (direct, normal insolation) into a cavity receiver whose aperture encircles the focal point of the concentrator. At the internal wall of the receiver the electromagnetic radiation is converted to thermal energy. A heat engine/generator assembly, which is mounted directly behind th receiver, then converts the thermal energy captured by the receiver to electricity. Developmental activity has been concentrated on relatively small power modules which employ 11- to 12-m-diam dishes to generate nominal power levels of approximately 20 kW. A comparison of advanced heat engines for use on the dish power module is presented in terms of the performance potential of each engine as weighed against its requirements for ...
Between 1973 and 1978 combined radiotherapy and chemotherapy were given to 22 patients with histologically proven Ewing's sarcoma. The combined chemotherapy consisted of cyclophosphamide, vincristin, adriamycin, as well as dacarbazine in some cases. The neoplasm was a localized one at the beginning of treatment in 14 of the 22. These patients received high-voltage rediotherapy to the primary focus at a focal dose between 42 and 55 Gray (4200-5500 rad), followed by chemotherapy. After 6-8 treatment cycles, adriamycin was replaced by methotrexate. Nine of the 14 patients survived without recurrence for 12 to over 59 months. Eight patients had extensive metastases at the beginning of treatment: they at first received only chemotherapy, followed by radiotherapy or operation, as indicated. Full clinical remission was achieved in five of them: in three this remission has now lasted for more than 18, 40 and 44 months, respectively. These results indicate that (1) ...
We review the recent development of bendable x-ray optics used for focusing of beams of soft and hard x-rays at the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory and at the Linac Coherent Light Source (LCLS) x-ray free electron laser (FEL) at the Stanford Linear Accelerator Center (SLAC) National Accelerator Laboratory. For simultaneous focusing in the tangential and sagittal directions, two elliptically cylindrical reflecting elements, a Kirkpatrick-Baez (KB) pair, are used. Because fabrication of elliptical surfaces is complicated, the cost of directly fabricated tangential elliptical cylinders is often prohibitive. Moreover, such optics cannot be easily readjusted for use in multiple, different experimental arrangements, e.g. at different focal distances. This is in contrast to flat optics that are simpler to manufacture and easier to measure by conventional interferometry. The tangential figure of a flat substrate is changed by placing ...
A 2-D model has been proposed to investigate the approximate estimation of the natural convection heat loss from modified cavity receiver of without insulation (WOI) and with insulation (WI) at the bottom of the aperture plane in our previous article. In this paper, a 3-D numerical model is presented to investigate the accurate estimation of natural convection heat loss from modified cavity receiver (WOI) of fuzzy focal solar dish concentrator. A comparison of 2-D and 3-D natural convection heat loss from a modified cavity receiver is carried out. A parametric study is carried out to develop separate Nusselt number correlations for 2-D and 3-D geometries of modified cavity receiver for estimation of convective heat loss from the receiver. The results show that the 2-D and 3-D are comparable only at higher angle of inclinations (60 {<=} {beta} {<=} 90 ) of the receiver. The present 3-D numerical model is compared with other well known cavity receiver ...
and the estimated parameter covariance matrix is. 5. (25) where p in this case is the number of elements in the vector . The parameter standard errors, ?, ...
BackgroundSeveral fractal and non-fractal parameters have been considered for the quantitative assessment of the vascular architecture, using a variety of test specimens and of computational...Full Text Available
Long-term disposal and management of low and intermediate-level radioactive waste is a major project of the nuclear power industry. Therefore, the selection of an underground waste repository has to be a geologically and seismologically stable storage. Easy transportation and emplacement is essential. The Wolsung nuclear power plant (NPP) of unit no. 1/2/ 3/ 4, which is responsible for the future of the energy industry, has already been constructed at the Wolsung site and a New NPP has recently been created at the Sinwolsung site. Radioactive waste used in the plant facilities, has piled up increasingly every year, but it should be taken to be managed at long-term underground storage disposal facilities. The Wolsung site for radioactivity waste repository was known to be relatively stable through various geological surveys, earthquakes, groundwater, engineering testing and analysis, but still more research related to the stability of the structure, in deep ...
Long-term disposal and management of low and intermediate-level radioactive waste is a major project of the nuclear power industry. Therefore, the selection of an underground waste repository has to be a geologically and seismologically stable storage. Easy transportation and emplacement is essential. The Wolsung nuclear power plant (NPP) of unit no. 1/2/ 3/ 4, which is responsible for the future of the energy industry, has already been constructed at the Wolsung site and a New NPP has recently been created at the Sinwolsung site. Radioactive waste used in the plant facilities, has piled up increasingly every year, but it should be taken to be managed at long-term underground storage disposal facilities. The Wolsung site for radioactivity waste repository was known to be relatively stable through various geological surveys, earthquakes, groundwater, engineering testing and analysis, but still more research related to the stability of the structure, in deep ...
Along the Japan Sea coast in Akita Prefecture and in the vicinity, there exist active fault groups, such as the Kitayuri thrust fault group in the south and Noshiro thrust fault group in the north. It is estimated that there is another fault, running from Akita City located between the above-said two thrust fault groups into the Hachiro-kata reclaimed land, roughly connecting the two thrust fault groups. This third fault is supposed to be related to the hypocenter of Tencho Earthquake of 830, but its location and structural configuration are not known, and it is not known whether it is an active fault, either. Investigations are conducted using S- and P-waves. The greatest problem in the use of P-waves is that there exists a layer in which signal attenuation is high and transmission is anomalously slow. This problem is ascribed to the layer pore water rendered unsaturated though slightly by the inclusion of air bubbles, and is explained for the most part by the ...
Sensor has been developed for the measurement of seismic wave rotary components. The vertical axis rotary component sensor is constituted of four L22Ds, similar to each other in performance, fixed in a ring formation on a metal bed. The ring is 22cm in diameter, and the four coils are connected so that their outputs will be added up. A horizontal axis rotary component sensor is built in the similar way. The rotary component sensors are all connected to a spectrum analyzer for the measurement of micromotions. It is found that the four-L22D combination can detect a rotary component of 335mV/deg/s. The sensor can detect both vertical and horizontal components with roughly the same sensitivity. A ring-form combination of conventional electromagnetic seismometers, though only as a temporary expedient, can perform high-resolution detection of rotary components and determine the absolute values of earthquakes or noise levels. In the case of a gyrosensor available on the ...
The requirements to design nuclear power plants for the effects of an instantaneous double-ended guillotine break (DEGB) of the reactor coolant piping have led to excessive design costs, interference with normal plant operation and maintenance, and unnecessary radiation exposure of plant maintenance personnel. This report describes an aspect of the NRC/Lawrence Livermore National laboratory-sponsored research program aimed at investigating whether the probability of DEGB in Reactor Coolant Loop Piping of nuclear power plants is acceptably small such that the requirements to design for the DEGB effects (e.g., provision of pipe whip restraints) may be removed. This study estimates the probability of indirect DEGB in Reactor Coolant piping as a consequence of seismic-induced structural failures within the containment of the GE supplied boiling water reactor at the Brunswick nuclear power plant. The median probability of indirect DEGB was estimated to be 2 x 10/sup -8/ per year. Using ...
As shown in various new examples, HABOG facility (Netherlands), CERNAVODA (Candu - Romania), KOZLODUY (WWER - Bulgaria), CHERNOBYL ( RMBK - Ukraine), MAYAK (Spent Fuel from submarine and Icebreakers - Russia), recent studies allow to confirm the flexibility and performances of the CASCAD system proposed by SGN, both in safety and operability, for the dry storage of main kinds of spent fuel. The main features are: A multiple containment barrier system: as required by international regulation, 2 independent barriers are provided (tight canister and storage pit); Passive cooling, while the Fuel Assemblies are stored in an inert atmosphere and under conditions of temperature preventing from degradation of rod cladding; Sub-criticality controlled by adequate arrangements in any conditions; Safe facility meeting ICPR 60 Requirements as well as all applicable regulations (including severe weather conditions and earthquake); Safe handling operations; Retrievability of the ...
The presence of natural fractures in reservoir rock can significantly enhance gas production, especially in tight gas formations. Any general knowledge of the existence, location, orientation, spatial density, and connectivity of natural fractures, as well as general reservoir structure, that can be obtained prior to active seismic acquisition and drilling can be exploited to identify key areas for subsequent higher resolution active seismic imaging. Current practices for estimating fracture properties before the acquisition of surface seismic data are usually based on the assumed geology and tectonics of the region, and empirical or fracture mechanics-based relationships between stratigraphic curvature and fracturing. The objective of this research is to investigate the potential of multicomponent surface sensor arrays, and passive seismic sources in the form of local earthquakes to identify and characterize potential fractured gas reservoirs located near ...
In the 5th year of the Japan International Cooperation Agency (JICA) Technical Cooperation Project 'Seismic Risk Reduction for Buildings and Structures in Romania', the implementing agency - National Center for Seismic Risk Reduction (NCSRR) and JICA jointly organized the International Symposium on Seismic Risk Reduction (ISSRR-2007) held in Bucharest at the Romanian Academy Library in the period April 26-27, 2007. The present volume contains the Proceedings of the International Symposium on Seismic Risk Reduction, ISSRR-2007. The Proceedings are organized in three parts: (I) keynote lectures, (II) papers on the results of JICA Project in Romania and (III) contributions from authors. Eight keynote lectures by specialists from Japan, USA, France and Greece, and fourteen papers on the results of JICA Project are included. The contributions from authors are divided in five sections: (i) Seismicity, Seismic Hazard and Site Effects, (ii) Seismic Vulnerability and Seismic Risk, (iii) Seismic ...
The 105-KE and 105-KW Fuel Storage Basins were constructed more than 35 years ago as repositories for irradiated fuel from the K East and K West Reactors. Currently, the basins contain irradiated fuel from the N Reactor. To continue to use the basins as desired, seismic adequacy in accordance with current US Department of Energy facility requirements must be demonstrated. The 105-KE and 105-KW Basins are reinforced concrete, belowground reservoirs with a 16-ft water depth. The entire water retention boundary, which currently includes a portion of the adjacent reactor buildings, must be qualified for the Hanford Site design basis earthquake. The reactor building interface joints are sealed against leakage with rubber water stops. Demonstration of the seismic adequacy of these interface joints was initially identified as a key issue in the seismic qualification effort. The issue of water leakage through seismicly induced cracks was also investigated. This issue, ...
The relationship between the fractal dimensions of spatial distributions of aftershocks and pre-existing active faults is examined. Fourteen mainshocks taking place in Japan were followed by aftershocks, and the aftershocks occur in swarms around the mainshocks. The epicentral distributions of the aftershocks exhibit fractal properties, and the fractal dimensions are estimated by using the two-point correlation integral. The pre-existing active fault systems observed in the 14 aftershock regions have fractal structures, and the fractal dimensions are estimated by using the box-counting method. A positive correlation between the estimated fractal dimensions is found, and it is independent on the mainshock magnitude. The correlation shows that aftershock distributions become less clustered with increasing the fractal dimensions of active fault systems. Namely, the fractal clusters of aftershocks are put under the constraint of the fractal properties of the pre-existing active fault ...
This is a prompt report. These days the importance of acquiring knowledge about the structure from the lower crust down to the upper mantle is often discussed with reference taken to Hyogo-ken Nanbu Earthquake. The Hidaka collision belt where the lower crust is exposed on the surface is a rare phenomenon in the world and has been the subject of seismic survey. As a part of the survey, experiments are conducted by the use of vibrations produced by Vibroseis and dynamite sources. Every one of the shot records (20-second record) from the two types of vibration sources contains a clear echo in the vicinity of 16 seconds supposedly from a level deeper than 40 kilometers, not to mention reflections from shallow levels. Although some studies have to be conducted before the reflecting geological boundary (possibly the upper mantle) of the echo near the 16-second point can be identified, yet this is probably the reflection from the deepest level ever obtained in the seismic ...
Results indicate that the probability of double-ended guillotine break (DEGB) in the reactor coolant loop piping of Westinghouse and Combustion Engineering plants is extremely low. It is recommended that the NRC seriously consider eliminating DEGB as a design basis event for reactor coolant loop piping in Westinghouse plants. Pipe whip restraints on reactor coolant loop piping could then be excluded or removed, and the requirement to design supports to withstand asymmetric blowdown loads could be eliminated. It is also recommended that the current requirement to couple safe shutdown earthquake (SSE) and DEGB be eliminated. Recognizing however that seismically induced support failure is the weak link in the DEGB evaluation, it is recommended that the strength of component supports, currently designed for the combination of SSE plus DEGB, not be reduced. The study indicates that the probability of DEGB in reactor coolant loop piping is sufficiently low under all ...
In Japan, high rigidity reinforced concrete foundations called the high-tuned type foundation have been generally used for the turbine generator foundations. In Europe, on the other hand, flexible steel foundations and spring-mounted reinforced concrete foundations are employed. These are called the low-tuned type foundation and have following excellent characteristics. (1) Excellent vibration isolation ability (2) By reducing the structural member size and weight, more effective utilization of space under the deck is possible. However, the low-tuned type foundation has a lower seismic resistance and it is said to be unsuitable type foundation in frequent seismic countries such as Japan and USA etc. from the view point of safety against earthquake. We have developed the new type low-tuned foundation having its excellent characteristics and seismic resistance ability called the spring-mounted turbine generator foundation supported by turbine house structure. This ...
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 tensile strengths of construction joints. Since the failure mechanism of a dam subjected to excessive ice loads is not well known, a ...
Minimally invasive thermotherapies for focal tissue destruction on the basis of laser-, microwave-, focused ultrasound-, or cryogeninduced changes of tissue temperature represent an alternative to surgical tissue ablation, particularly in the treatment of tumors. The thermotherapy modalities listed necessitate indirect guidance and monitoring, since they often do not lend themselves to immediate visual control. In the brain, in head and neck tumors, in the liver, and in the prostate, MRI reliably and accurately delineates both the positions of interstitial thermotherapy applicators and - in contrast-enhanced, T1-weighted images - the perfusion defects in tissue necrosis induced by thermotherapy. The transfer of results of in-vitro and in-vivo model studies to assess interstitial temperature and lesion development during thermotherapy to the actual treatment of patients, however, is still in an initial phase. Further development of both rapid MRI sequences and MRI ...
Two extruded magnesium alloys, AZ31 and AZ61 were selected to evaluate the influence of process parameters on the material forgeability. The processing parameters considered for forging magnesium alloys were: compression load in the range 55 KN to 60 KN and forging temperature, in the range of ambient temperature to 300 C. Uniaxial compression tests were conducted to establish the strain-temperature relationship. The influences of process parameters on the microstructure were also evaluated. (orig.)
Correlations of the Woods-Saxon four-parameter optical potential of scattering of 38 MeV #alpha# particles on sup(68)Zn have been analyzed. A search for discrete sets of potential parameters and functional ratios between different parameters is carried out.
The orbit response matrix (ORM) method [1] is applied to model the Fermilab Booster with parameters such as the BPM gains and rolls, and parameters in the lattice model, including the gradient errors and magnets rolls. We found that the gradients and rolls of the adjacent combined-function magnets were deeply correlated, preventing full determination of the model parameters. Suitable constraints of the parameters were introduced to guarantee an unique, equivalent solution. Simulations show that such solution preserves proper combinations of the adjacent parameters. The result shows that the gradient errors of combined-function magnets are within design limits.
It is shown that the method used for comparing theoretical and experimental results is erroneous and the values of the couple stress parameters obtained for blood flow are incorrect. A method for determining the couple stress parameters is presented. The computational work in the improved method is considerably less. It is observed that both the couple stress parameters are functions of concentration. An empirical relation between concentration and the stress parameters is obtained. The shear viscosity and non-dimensional axial velocity are functions of concentration. Some uses of determining the values of the couple stress parameters are suggested.
A class of nonlinear models combining a pharmacokinetic compartmental model and a pharmacodynamic Emax model is introduced. The locally D-optimal (LD) design for a four-parameter composed model is found to be a saturated four-point uniform LD design with the two boundary points of the design space in the LD design support. For a five-parameter composed model, a sufficient condition for the LD design to require the minimum number of sampling time points is derived. Robust LD designs are also investigated for both models. It is found that an LD design with $k$ parameters is equivalent to an LD design with $k-1$ parameters if the linear parameter in the two composed models is a nuisance parameter. Assorted examples of LD designs are presented.
The problem of electrical parameters identification in complex systems, and in particular in electric railway traction systems, is considered. Parameters are determined by an indirect approach: only the terminal variables (voltages and currents and, impedance and admittance, which can be readily calculated) are measured and the per-unit-length electrical parameters are determined using a multiconductor transmission line model of the track section under test. It will be shown that some parameters cannot be measured directly, that they are not constant with frequency and that they may depend on other external conditions. An indirect method for parameters identification is proposed through an adaptive algorithm (AA), so that the calculated terminal variables match the measured ones. The AA is...
Purpose: Evaluation of the diagnostic efficacy and cost-benefit of contrast enhanced CT (CT) and MRI pre- and post-SPIO-particles in focal hepatic disease with consideration of therapeutic outcome. Results: In 34/52 (65.4%) of the cases the correct diagnosis was primarily stated by CT (sensitivity [se.] 85.2%, specificity [sp.] 44.0%). In additional 10/52 of the cases unenhanced MRI (se. 91.4%, sp. 75.0%) enabled correct diagnoses, and in another 6 cases the diagnosis was established only by SPIO-MRI (se. 100%, sp. 86.7%). Considering the possible therapeutic recommendation arising from each modality, CT would have induced needless therapy costs of 191,042 DM, unenhanced MRI of 171,035 DM, and SPIO-MRI of 7,311 DM. In comparison to the real therapy costs of 221,873 DM, this would have corresponded to an unnecessary increase of therapy costs of 86.1%, 77.1%, and 3.3%, respectively. In two cases (91 hemangioma, 1 regenerative nodule) all modalities failed, causing ...
During the 2007 Niigataken Chuetsu-oki earthquake, strong ground motion with the peak acceleration of 680 cm/s/s which was larger than that of the empirical prediction was recorded at the base mat of the No.1 reactor building of Kashiwazaki-Kariwa Nuclear Power Station (NPS). Furthermore, in the Kashiwazaki-Kariwa NPS, over twice difference of 680 vs. 322 cm/s/s of peak acceleration between the No.1 and the No.6 reactor buildings was observed on the base mat. From the results of recent research, it is suggested that the deep sedimentary layers can be one of the important factors to elucidate these phenomena. In this study, at first, the applicability of microtremor array measurements for estimation of deep S-wave velocity structure (#approx#Vs=3 km/s layer) are discussed. Vertical microtremors were observed in three arrays at the Kashiwazaki-Kariwa NPS with the maximum station spacings of 3.04 km, 1.49 km and 0.75 km, respectively. The Rayleigh wave phase velocity ...
Waveform correlation detectors compare a signal template with successive windows of a continuous data stream and report a detection when the correlation coefficient, or some comparable detection statistic, exceeds a specified threshold. Since correlation detectors exploit the fine structure of the full waveform, they are exquisitely sensitive when compared to power (STA/LTA) detectors. The drawback of correlation detectors is that they require complete knowledge of the signal to be detected, which limits such methods to instances of seismicity in which a very similar signal has already been observed by every station used. Such instances include earthquake swarms, aftershock sequences, repeating industrial seismicity, and many other forms of controlled explosions. The reduction in the detection threshold is even greater when the techniques are applied to arrays since stacking can be performed on the individual channel correlation traces to achieve significant array ...
Test firings of 120-mm rounds were performed to characterize effects due to the combustible cartridge cases used. Comparisons were made between measured ballistic parameters, especially gas pressures, and those predicted by computerized simulation calcula...
In this paper, the compulsory site requirements and the site design assumptions which are being used for the present ITER plant are briefly described. A set of different parameters from the site design assumptions is also described, which was adopted as an additional exercise for cost sensitivity analysis of the ITER plant for these parameters. (orig.) 1 refs.
In this paper, the compulsory site requirements and the site design assumptions which are being used for the present ITER plant are briefly described. A set of different parameters from the site design assumptions is also described, which was adopted as an additional exercise for cost sensitivity analysis of the ITER plant for these parameters. (orig.)
The sensitivity analysis summarized in this paper was made to determine the parameters of greatest influence in the prediction of radon barrier cover thickness for the stabilization of uranium mill tailings piles. Such information provides the basis for setting priorities and levels of effort for data collection, and improves knowledge of the sources of uncertainty in the calculation of cover thickness. In the context of this paper, the influence of a parameter on cover thickness incorporates two effects: (1) the sensitivity of the mathematical formulation to changes in a parameter's value, and (2) the range of values that a parameter may take on under site-specific conditions. Of the several parameters that are used in the calculations, the most influential are cover moisture content, cover radon diffusion coefficient, tailings radium concentration and tailings radon emanating ...
The goal of this research project was to determine the eff ects of geometric and mechanical parameters characterizing the soil-structure interaction developed in a buried pipe installation. Parameters such as pipe ring stiff ness, bedding thickness, trenc...
Effects associated with the temperature dependence of the level density parameter, a(T), are investigated in connection with neutron evaporation processes. Different approximations, for this temperature dependence, are compared for the case of neutron emission from the compound nucleus /sup 209/Pb.
We study a rapidly convergent modification of a two-sided method for the approximate integration of a boundary-value problem with parameters in boundary conditions for a system of quasilinear second-order differential equations.
The goal of this study was to evaluate the clinical and urodynamic features in Korean men with lower urinary tract symptoms (LUTS) and to determine non-invasive parameters for predicting bladder outlet...Full Text Available
The pharmacokinetic parameters of amikacin and ceftazidime were assessed in four patients undergoing hemofiltration for septic shock. The parameters were assessed during hemofiltration and in the interim...Full Text Available
If we decompose C1 using SVD the parameter covariance matrix can be inverted to ... However, we can analyze the parameter covariance matrix directly by ...
BackgroundPregnancy is accompanied by several hemodynamic, biochemical and hematological changes which revert to normal values after labor. The mean values of these parameters have...Full Text Available
An elliptic equation in a rectangle with coefficients depending on a fast variable and with its period being a small parameter is considered. An asymptotic expansion of the solution up to an arbitrary degree of the small parameter is constructed and substantiated by applying the two-scale expansion method.
Derivations are made for the mass and the mass-turnover time scale of an accretion disk as a function of the accretion rate, the observed disk radius, the non-viscous disk radius, and two parameters. These parameters depend on the effectiveness of viscosity and tidal angular momentum loss. Application is made to DQ Herculis.
One of the key issues in safety assessment of high-level nuclear waste disposal is evaluating the effects of uncertainty inherent in radionuclide migration parameter values. In this paper, radionuclide transport parameter values and error variances (uncertainties) from in-situ tracer experiments, carried out in a single fracture at the Aespoe Hard Rock Laboratory (HRL) in Sweden, are identified by solving the inverse problem in a framework of the maximum likelihood theory. From the results, it is found that the parameter value uncertainty caused by a conceptual model of radionuclide migration is greater than that caused by a fluctuation in the observed breakthrough curve data. (author)
Design methods and parameters are described which are addressed when considering consequences of a postulated pipe rupture event in a nuclear plant design. Parameters discussed are break opening time and size, resultant blowdown characteristics of the effluent from the broken pipe, jet reaction and impingement loading, pipe motion, and pipe impact loading on steel and concrete structures. The impact the various parameters have on overall plant designs and conservatisms inherent in each consideration are evaluated in a qualitative nature. Finally, recommendations are provided for each parameter discussed for further evaluation and study.
Nuclear physics parameters of the Wolsung CANDU-PHW reactor are computed by use of the PHWCELL computer code that is an improved version of LATREP. The PHWCELL code mainly computes cell parameters of heavy water moderated reactors, and modeling scheme of heavy water reactor cell calculations has been developed with the PHWCELL computer code. The reactor operating conditions considered in the study are cold zero power (CZP) and hot full power (HFP) with equilibrium poison. The cell parameters are also computed as a function of fuel burnup and the numerical results are compared with the results in PSR of the Wolsung unit and in the previous study. (author).
... commands may be input from a terminal or they ... up the outcomes of the stochastic parameters corre- ... queue of subproblems to be solved, the first ...
Stochastic Kronecker graphs supply a parsimonious model for large sparse real world graphs. They can specify the distribution of a large random graph using only three or four parameters. Those parameters have however proved difficult to choose in specific applications. This article looks at method of moments estimators that are computationally much simpler than maximum likelihood. The estimators are fast and in our examples, they typically yield Kronecker parameters with expected feature counts closer to a given graph than we get from KronFit. The improvement was especially prominent for the number of triangles in the graph.
By employing the higher dimensional version of the Wu-Yang Ansatz we obtain magnetically charged new black hole solutions in the Einstein-Yang-Mills-Lovelock (EYML) theory with second ($\\alpha2$) and third ($\\alpha3$)order parameters. These parameters, where $\\alpha2$ is also known as the Gauss-Bonnet parameter, modify the horizons (and the resulting thermodynamical properties) of the black holes. It is shown also that asymptotically, these parameters contribute to an effective cosmological constant -without cosmological constant- so that the solution behaves de-Sitter (Anti de-Sitter) like.
In Nuclear Magnetic Resonance (NMR) imaging, contrast is dependent on the emission of radiofrequency waves by atomic nuclei, balanced by several parameters. The high information content of NMR images is due to the multiplicity of its parameters. However, this advantage introduces a difficulty in the interpretation of the contrast. There are three contrast parameters for each tissue: hydrogen nuclei density; relaxation time T1; relaxation time T2. Contrast may be enhanced towards any of these parameters by increasing the emission of radiowaves by atomic nuclei using particular pulse sequences.
The results for development of methods and computer programs for integrated optimization of parameters of perspective fast reactors are given. The possibilities of the program for the reactor campaign calculation are analysed. This program is based on utilisation of the Bubnov-Galerkin method and Wigner disturbance theory. The possibility of application of approximation methods for the optimization researches is discussed. The results of development of the programs for complex reactor computations with account of control rods system and change of physical parameters in the reactor campaign are discussed. (author).
The thermal decrease of the order parameter can empirically be described by a single T{sup {epsilon}} power law with an exponent {epsilon} which depends on the dimensionality of the magnetic interactions and on whether the spin quantum number is integral or half-integral. We present experimental examples in which the order parameter shows a crossover between different T{sup {epsilon}} power laws as a function of temperature. This indicates that the magnetic interactions can change their dimensionality as a function of temperature. (orig.)
A physical model of free-electron laser (FEL) amplifier with variable-parameter wiggler magnets for one-dimensional numerical simulation is presented and a numerical example is given. The wiggler parameters, efficiency of energy conversion between electron beam and laser field, laser intensity, phase-space distributions and energy spectrum of electrons are computed. The period of synchronous oscillation and saturation value of laser intensity agree with estimated one.
We study the dynamics of the scalar tensor cosmological model in the presence of tachyon field. In an alternative approach, in two exponential and power law form of the scalar field functions in the model, field equations are solved by simultaneously best fitting the model parameters with the most recent observational data. This approach gives us an observationally verified interpretation of the dynamics of the universe. We then discuss the best fitted of equation of state parameter, the statefinder parameters and the reconstructed scalar field in the model.
The kinetic parameters, ..cap alpha.. the coupling coefficient and tau-bar the mean neutron transit time have been determined using a reactor oscillator on the coupled-core of the Queen Mary College research reactor. By using correlation techniques it has proved possible to use detectors small enough to be inserted in the fuel tanks. It is shown that the simplified Baldwin model with one-group diffusion theory is inadequate to describe the kinetic behaviour and the experimentally-determined parameters are dependent upon the positioning of the detectors.
Aim: To determine whether experience improves the consistency of visual search behaviour in fracture identification in plain radiographs, and the effect of specialization. Material and methods: Twenty-five observers consisting of consultant radiologists, consultant orthopaedic surgeons, orthopaedic specialist registrars, orthopaedic senior house officers, and accident and emergency senior house officers examined 33 skeletal radiographs (shoulder, hand, and knee). Eye movement data were collected using a Tobii 1750 eye tracker with levels of diagnostic confidence collected simultaneously. Kullback-Leibler (KL) divergence and Gaussian mixture model fitting of fixation distance-to-fracture were used to calculate the consistency and the relationship between discovery and reflective visual search phases among different observer groups. Results: Total time spent studying the radiograph was not significantly different between the groups. However, the expert groups had a higher number of true ...
Surgical resection is the only curative treatment strategy for intrahepatic cholangiocarcinoma (CC). Therefore, accurate staging is essential for appropriate management of patients with CC. We assessed the usefulness of 2-["1"8F]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) in the staging of CC. We undertook a retrospective review of FDG PET images in 21 patients (10 female, 11 male; mean age 57 years) diagnosed with CC. Ten patients had hilar CC and 11, peripheral CC. Patients underwent abdominal magnetic resonance imaging (MRI) (n=20) and computed tomography (CT) (n=12) for the evaluation of primary tumours, and chest radiography and whole-body bone scintigraphy for work-up of distant metastases. For semi-quantitative analysis, the maximum voxel standardised uptake value (SUV_m_a_x) was obtained from the primary tumour. All peripheral CCs showed intensely increased FDG uptake, and some demonstrated ring-shaped uptake corresponding to peripheral rim enhancement on ...
The Infrared Camera (IRC) is one of the scientific focal plane instruments on board the ASTRO-F infrared astronomical satellite. The IRC is designed for wide field imaging and slit-less spectroscopic observations at near- and mid-infrared wavelengths. The IRC consists of three channels; NIR, MIR-S and MIR-L, each of which covers wavelengths of 2-5, 5-12 and 12-26 micron, respectively. All channels adopt compact refractive optical designs. Large format array detectors (a InSb 512 x 412 array and two Si:As IBC 256 x 256 arrays) are employed. Each channel has 10 x 10 arcminutes wide FOV with diffraction-limited angular resolution of 70cm aperture of the liquid helium cooled telescope at wavelengths over 5 micron. A 6-position filter wheel is placed at the aperture stop in each channel, and has three band-pass filters, two grisms/prisms and a mask for dark current measurements. The 5 sigma sensitivity of one pointed observation is estimated to be 2, 11 and 62 micro-Jy ...
The National Ignition Facility (NIF) is a proposed Department of Energy facility which will contribute to the resolution of important Defense Program and inertial fusion energy issues for energy production in the future. The NIF will consist of a laser system with 192 independent beamlets transported to a target chamber. The target chamber is a multi-purpose structure that provides the interface between the target and the laser optics. The chamber must be capable of achieving moderate vacuum levels in reasonable times; it must remain dimensionally stable within micron tolerances, provide support for the optics, diagnostics, and target positioner; it must minimize the debris from the x-ray and laser light environments; and it must be capable of supporting external neutron shielding. The chamber must also be fabricated from a low neutron activation material. The fusion reaction in the target gives off neutrons, x-ray and gamma rays. The x-rays and gamma rays interact with the interior of ...
Our aim was to investigate the diagnostic reliability of multidetector-row computed tomography (MDCT) for preoperative assessment of local tumoral spread in hilar cholangiocarcinoma. Thirteen of 30 consecutive patients with hilar cholangiocarcinoma who underwent surgery, excluding 17 patients who underwent biliary drainage or preoperative portal embolization, were retrospectively evaluated. Using MDCT systems of 4 detector rows or 16 detector rows, plain and dynamic contrast-enhanced images of three phases were obtained. Extent of tumor spread and lymph node metastasis were assessed with MDCT and compared with histopathological findings. The Bismuth-Corlette classification of hilar cholangiocarcinoma with MDCT were type I, 1 patient; type IIIa, 3 patients; type IIIb, 4 patients; and type IV, 5 patients; those with histopathological findings were type I, 1 patient; type IIIa, 2 patients; type IIIb, 4 patients; and type IV, 6 patients. One patient diagnosed as type IIIa with MDCT was ...
By contrast to the large mass, complexity and recirculating power of conventional drivers for inertial confinement fusion (ICF), antiproton annihilation offers a specific energy of 90MJ/{micro}g and thus a unique form of energy packaging and delivery. In principle, antiproton drivers could provide a profound reduction in system mass for advanced space propulsion by ICF. We examine the physics underlying the use of antiprotons ({bar p}) to drive various classes of high-yield ICF targets by the methods of volumetric ignition, hotspot ignition and fast ignition. The useable fraction of annihilation deposition energy is determined for both {bar p}-driven ablative compression and {bar p}-driven fast ignition, in association with 0-D and 1-D target burn models. Thereby, we deduce scaling laws for the number of injected antiprotons required per capsule, together with timing and focal spot requirements. The kinetic energy of the injected antiproton beam required to ...
Background. Through PSA screening the rate of prostate cancers detected at an early stage has increased significantly; thus a decrease in mortality can be expected in the near future. Despite all scientific efforts, however, the molecular mechanisms underlying the development and progression of prostate cancer remain poorly understood. Prostate cancer is a disease of aging men and epidemiological evidence supports a major contribution to its development through diet, lifestyle and environmental factors. Genetic instability is the basic phenomenon of tissue cell cancerisation. This instability can be hereditary or due to mutations and other chromosomal aberrations acquired during life. In recent years a large number of interesting data have been collected which show the relationships between focal atrophy and genetic instability of the prostate epithelia. Atrophy can be the result of prostatitis, ischemia as well as of oxidative stress (diet). Several chromosomal ...
This thesis is concerned with the optimization and development of the production of nanofocusing refractive X-ray lenses. These optics made of either silicon or diamond are well-suited for high resolution X-ray microscopy. The goal of this work is the design of a reproducible manufacturing process which allows the production of silicon lenses with high precision, high quality and high piece number. Furthermore a process for the production of diamond lenses is to be developed and established. In this work, the theoretical basics of X-rays and their interaction with matter are described. Especially, aspects of synchrotron radiation are emphasized. Important in X-ray microscopy are the different optics. The details, advantages and disadvantages, in particular those of refractive lenses are given. To achieve small X-ray beams well beyond the 100 nm range a small focal length is required. This is achieved in refractive lenses by moving to a compact lens design where ...
Endogenous fluorescence provides morphological, spectral, and lifetime contrast that can indicate disease states in tissues. Previous studies have demonstrated that two-photon autofluorescence microscopy (2PAM) can be used for noninvasive, three-dimensional imaging of epithelial tissues down to approximately 150 ?m beneath the skin surface. We report ex-vivo 2PAM images of epithelial tissue from a human tongue biopsy down to 370 ?m below the surface. At greater than 320 ?m deep, the fluorescence generated outside the focal volume degrades the image contrast to below one. We demonstrate that these imaging depths can be reached with 160 mW of laser power (2-nJ per pulse) from a conventional 80-MHz repetition rate ultrafast laser oscillator. To better understand the maximum imaging depths that we can achieve in epithelial tissues, we studied image contrast as a function of depth in tissue phantoms with a range of relevant optical properties. The phantom data agree ...
The epileptogenic and neurodegenerative effects of gamma-dendrotoxin, from Dendroaspis angusticeps, a specific blocker of a non-inactivating, voltage-sensitive K+ channel, were studied after focal injection into one dorsal hippocampus in rats pretreated with CGP040116, a N-methyl-D-aspartate (NMDA) receptor antagonist, and in rats bearing a monolateral surgical lesion of the Schaffer collaterals whose terminals originate from CA3 pyramids and release glutamate in the CA1 hippocampal area. Administration of 35 pmol gamma-dendrotoxin elicited in all of the treated animals (n=8) bilateral EEG discharges and damage to the hippocampal formation. Quantitation of the damage revealed significant bilateral neuronal cell loss in the CA1, CA3 and CA4 pyramidal cell layers. The lowest dose (0.35 pmol; n=4) of the toxin used did not affect EEG activity and failed to cause significant hippocampal cell loss whereas the 3.5 pmol (n=6) dose caused EEG seizures and hippocampal cell ...
The absorption of solar heat and the attendant thermal and mechanical loadings on the tubes of cavity receivers depend predominantly on the flux distribution of the incident solar radiation. For an axially symmetric cavity receiver with a parabolic dish collector, it is simple to determine the insolation pattern on the receiver internal surfaces if the system is ideal. In such a system the surface of the dish is perfectly parabolic (no contour flaws are present), and the sun's central ray impinges on the dish surface parallel to the focal axis (no sun tracking flaws are present). These two conditions cannot be achieved in practice, and therefore the feasible parabolic dish system is referred to as a real system although, in actual fact, it is only an approximation to any actual system. The purpose of this paper is to devise calculation principles which permit analysis of a receiver designed for ideal conditions to verify its structural adequacy under the ...
The convolution/superposition calculations for radiotherapy dose distributions are traditionally performed by convolving polyenergetic energy deposition kernels with TERMA (total energy released per unit mass) precomputed in each voxel of the irradiated phantom. We propose an alternative method in which the TERMA calculation is replaced by random sampling of photon energy, direction and interaction point. Then, a direction is randomly sampled from the angular distribution of the monoenergetic kernel corresponding to the photon energy. The kernel ray is propagated across the phantom, and energy is deposited in each voxel traversed. An important advantage of the explicit sampling of energy is that spectral changes with depth are automatically accounted for. No spectral or kernel hardening corrections are needed. Furthermore, the continuous sampling of photon direction allows us to model sharp changes in fluence, such as those due to collimator tongue-and-groove. The use of explicit ...
The authors assess the role of Computed Topography in the diagnosis and management of multiple myeloma (MM) and investigate if Computed Tomography findings can influence the clinical approach, prognosis and treatment. 273 multiple myeloma patients submitted to Computed Tomography June 1994, to December, 1996. The patients were 143 men and 130 women (mean age: 65 years): 143 were stage I, 38 stage II and 92 stage III according to Durie and Salomon's clinical classification. All patients were submitted to blood tests, spinal radiography and Computed Tomography, the latter with serial 5-mm scans on several vertebral bodies. Computed Tomography despicted vertebral arch and process involvement in 3 cases with the vertebral pedicle sign. Moreover, Computed Tomography proved superior to radiography in showing the spread of myelomatous masses into the soft tissues in a case with solitary permeative lesion in the left public bone, which facilitated subsequent biopsy. As for extraosseous ...
Full text: Chronic fatigue syndrome (CFS) is a complex disorder characterised by profound fatigue and neuropsychiatric dysfunction. Previous studies with cerebral perfusion SPECT (rCBF) scans were performed with inhomogeneous patient populations and were not analysed with Statistical Parametric Mapping (SPM). We have used SPM to study subjects with moderate CFS based on the Fukuda criteria, who were not on medication and not depressed, compared to age matched control subjects. An apparent bimodal age distribution has been observed in CFS. Subjects were therefore divided into two age groups: 16-35 or under 35 (17 CFS, 11 control) and 36-61 or over 35 (15 CFS, 15 control). HMPAO brain SPECT was acquired on a 3-head camera. After lower window scatter subtraction, reconstruction with attenuation correction (mu=0.15/cm) and editing of facial activity, scans were spatially normalised (affine + 2x3x2 nonlinear) to SPM's anatomical space. SPM statistical analysis yielded the location, ...
Phase-contrast imaging with a practical cone-beam X-ray tube has been realized for clinical use in digital mammography using computed radiography (CR). To perform phase-contrast imaging, the X-ray detector must be distanced from an object so that the phase-contrast image achieves magnification; in a mammography unit dedicated to phase-contrast imaging, the magnification ratio is 1.75. When using an X-ray tube with a 0.1-mm focal spot, it appears that the penumbra in magnification blurs both projected images and the phase contrast, which generates an edge effect. However, where the sampling pitch of the CR plate is 43.75 {mu}m, the blur stretches the width of the phase contrast so that unit pixels in the detector can capture it. Note that the width of an ideal phase contrast using an X-ray point source results in a phase contrast too narrow for detection with CR. In addition to phase contrast improving image quality, a re-scaling effect increases image sharpness in ...
Purpose. We have tested a procedure of focal injection of the contrast medium Lipiodol as a fiducial marker for image-guided boost of the tumor in bladder cancer radiotherapy (RT). In this study, we have evaluated the feasibility and the safety of the method as well as the inter- and intra-fraction shift of the bladder tumor. Materials and methods. Five patients with muscle invasive urinary bladder cancer were included in the study. Lipiodol was injected during flexible cystoscopy into the submucosa of the bladder wall at the periphery of the tumor or the post resection tumor-bed. Cone-beam CT (CBCT) scans were acquired daily throughout the course of RT. Results. Lipiodol demarcation of the bladder tumor was feasible and safe with only a minimum of side effects related to the procedure. The Lipiodol spots were visible on CT and CBCT scans for the duration of the RT course. More than half of all the treatment fractions required a geometric shift of 5 mm or more to ...
The geological structure of Mesita del Buey at Technical Area 54 (TA-54) was examined using precise surveying of the contact between units 1v and 2 of the Tshirege Member of the Bandelier Tuff at 3.5 km along the north wall of Pajarito Canyon and 0.6 km along the north wall of a tributary to Canada del Buey. Estimated structure contours on this contact indicate typical strikes of N40E to N70E along this part of Mesita del Buey, although the apparent strike of the tuff is E-W at the western part of the survey. Typical dips are 1.0{degree} to 2.0{degree} to the east or southeast, with an estimated maximum dip of 3.2{degree} near the west end of Material Disposal Area G. Thirty seven faults with vertical displacements of 5 to 65 cm were observed in outcrop along the Pajarito Canyon traverse, and, due to the incomplete exposure of the unit 1v-unit 2 contact, many more faults of this magnitude undoubtedly exist. The faults have a wide range in strike and have either down-to-the-west and ...
Structural complexities reduce the homogeneity necessary for a site characterization model to an unacceptable level for performance assessment for radioactive waste disposal sites. The proposed site lies between the northern, stable Diablo platform and the southern, mobile Mesozoic Chihuahua tectonic belt. Structural movement along this interface has been active for the past 14,000 years. In addition, the area lies along the northern margin of the Permian Marfa basin and the northeastern margin of the deeply faulted Hueco bolson segment of the late Cenozoic Rio Grande rift system. Recent seismic activity with extensive surface rupture in Quitman Canyon (30 mi southeast of the site) is also documented from the 1931 Valentine, Texas, earthquake (6.4 Richter scale). The site is underlain by either a thrust fault or the complex terminus of a Mesozoic thrust fault. This fault is a segment of the continuous thrust sheet extending from exposures in the Sierra Blanc area, ...
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 low order nonlinear ...
Atmospheric and ionospheric perturbations associated with the acoustic-gravity waves (AGW) with typical frequencies of a few hertz -millihertz are considered. These events may be caused by the influence from space and atmosphere as well as by oscillations of the Earth surface and other near-surface phenomena. The surface sources include long-period oscillations of the Earth's surface, earthquakes, explosions, thermal heating, seisches and tsunami waves. The wavelike phenomena manifest themself as travelling disturbances of air (in the atmosphere) and of electron density (in the ionosphere). Travelling ionospheric disturbances (TIDs) are well detected by radio physical methods. AGW generation by near-surface sources is modeled by the numerical solution of the equation of geophysical fluid dynamics for different sources in two-dimensional non-linear dissipative compressible atmosphere. The numerical calculations are based on the FCT (Flux Corrected Transport) ...
In Chapter 2 the evaluation methods of input ground motions for seismic design are summarized and especially the empirical and/or stochastic Green's function method is introduced in order to calculate the broadband strong motions based on the physically reliable fault model. Then the evaluation procedure is applied to the Ulsan fault system near which Wolsung nuclear power plant is located. In chapter3, the PSHA case studies for Wolsung NPP site are performed, in which multi attenuation equations of earthquake motions are adopted. Moreover, the results of seismic hazard evaluation for eight sites in Korea are shown. In addition, the contents of two literatures on seismic hazard evaluation are introduced. In chapter 4, isolation devices for emergency diesel generator have been studied. The models for friction-pendulum system, high damping rubber bearing and natural rubber bearing are developed and implemented in the TDAP-III. Then, the rubber bearings as ...
Japan International Cooperation Agency (JICA) Technical Cooperation Project on Reduction of Seismic Risk for Buildings and Structures started in Romania on October 1, 2002. The aim of the Project is to strengthen the capacity of earthquake disaster related activities in Romania. The Project approval is the result of four years of intensive efforts made by professionals from Technical University of Civil Engineering Bucharest (UTCB), Ministry of Transport, Constructions and Tourism (MTCT), Romania, National Building Research Institute (INCERC) Bucharest, JICA, Building Research Institute (BRI), Tsukuba, and National Institute for Land, Infrastructure and Management (NILIM), Tsukuba, Japan. The duration of the Project is five years. The implementing agency is the National Center for Seismic Risk Reduction (NCSRR) as a public institution of national interest under MTCT. The activities are carried out by NCSRR in partnership with UTCB and INCERC. During the Project ...
Dams and reservoirs are among one of the most sensitive of all development Project, in terms of pervasiveness of their influence in altering the environmental conditions and resources. In the present study, major dams and reservoir projects are reviewed, from the environmental point of view. Dams and Reservoir projects bring about major changes in the immediate environment, thus affecting public health, settlements, farmlands, roads and historical sites. Impacts on human population and wildlife may be profound. Tropical diseases, involving fresh-water hosts or vectors in their transmission, are often common around new reservoirs. Large lakes create limnological changes, excessive evaporation, seepage, disturbance in water-table and increased tendencies of landslides and earthquakes. Micro climatic changes are possible, such as fog formation, increased cloudiness and modified rainfall-patterns. Retention of sediment results in silting up of reservoirs. Water ...
In FY-2000, Engineering at Lawrence Livermore National Laboratory faced significant pressures to meet critical project milestones, and immediate demands to facilitate the reassignment of employees as the National Ignition Facility (the 600-TW laser facility being designed and built at Livermore, and one of the largest R&D construction projects in the world) was in the process of re-baselining its plan while executing full-speed its technology development efforts. This drive for change occurred as an unprecedented level of management and program changes were occurring within LLNL. I am pleased to report that we met many key milestones and achieved numerous technological breakthroughs. This report summarizes our efforts to perform feasibility and reduce-to-practice studies, demonstrations, and/or techniques--as structured through our technology centers. Whether using computational engineering to predict how giant structures like suspension bridges will respond to massive ...
Restructuring was carried out on a sedimentary basin structure model of the Osaka plain including Osaka Bay by using newly obtained underground structural data. After the Hygoken-nanbu Earthquake of 1995, a large number of underground structure investigations have been performed in Osaka Bay and urban areas of Kobe and Osaka. However, very few surveys have been done in areas peripheral to Osaka Prefecture, such as the Ikoma area. Therefore, an attempt has been made to increase the number of measuring points to acquire underground structural data of these areas. Estimation of basic rock depths has utilized the dominant cycles in H/V spectra obtained from micro vibration survey, and good correlation of the base rock depths derived by a refraction exploration and a deep-bed boring investigation. With regard to bed division and P- and S- wave velocities in sedimentary beds in the Osaka sedimentary basin, an underground structure model was prepared, which was divided ...
Discussed in this paper are the P-wave and S-wave zero-offset VSPs carried out utilizing boreholes located in Nada Ward, Kobe City, and Hokudan-cho, Hyogo Prefecture, as part of the deep layer boring survey following Hanshin Earthquake Disaster. This effort aims at the elucidation of P-wave and S-wave velocity structures, high-precision identification of data obtained by the surface reflection method, and collection of basic data for active faults investigation in the future. Among the velocity structures obtained for various layers, the S-wave velocity structures in particular agree with the stratigraphy excellently and may be utilized in seismic analyses to be conducted in the future. Reflection from geological boundaries is received with precision, providing accurate information about correlation between reflection and geological cross sections. The records will be useful in formulating plans for reflection surveys for instance of the boundary between the Osaka ...
We describe a 2 parameter family of polygon exchange transformations parameterized by points in a square. Whenever the two parameters are irrational, the polygon exchange has periodic orbits of arbitrarily large period. We show that for almost all parameters, the polygon exchange map has the property that almost every point is periodic. However, there is a dense set of irrational parameters for which this fails. By choosing parameters carefully, the measure of non-periodic points can be made arbitrarily close to full measure. These results are powered by a notion of renormalization which holds in a more general setting. Namely, we consider a renormalization of tilings arising from the Corner Percolation Model.
Experiences with the model parameter identification of the excitation system (EXS) and the power system stabilizer (PSS) for Mingtan{number_sign}6 pumped storage generation unit of Taiwan Power System are presented in this paper. The input-output data corresponding to each block of the EXS and PSS were obtained when the finalization tests of this unit were performed. The generalized least squares (GLS) approach is introduced and employed to identify the desired parameters of the noisy excitation system and PSS models. In this method, the reduction technique of biased estimates due to the non-white (correlated) identification residual is also applied to improve the accuracy of identification. The results of the parameter estimation are satisfactory. The GLS parameter identification method using the measured data at finalization tests is then suggested from the viewpoint of economy and engineering.
Obtaining the set of cosmological parameters consistent with observational data is an important exercise in current cosmological research. It involves finding the global maximum of the likelihood function in the multi-dimensional parameter space. Currently sampling based methods, which are in general stochastic in nature, like Markov-Chain Monte Carlo(MCMC), are being commonly used for parameter estimation. The beauty of stochastic methods is that the computational cost grows, at the most, linearly in place of exponentially (as in grid based approaches) with the dimensionality of the search space. MCMC methods sample the full joint probability distribution (posterior) from which one and two dimensional probability distributions, best fit (average) values of parameters and then error bars can be computed. In the present work we demonstrate the application of another stochastic method, named Particle ...
The classical theory of collisional broadening and shift parameters (?, ?) of an isolated spectral line was used to obtain simple analytical formulas for calculating both ? and ?. These formulas were obtained on the assumption that the short range interaction is effective only in the broadening while the long range is effective in the shift of the spectral line. These parameters ? and ? depend on the limiting phase shifts responsible for broadening ?b and shift ??. It was found that the values of ?b and ?? are not equal to each other as was proposed by Weisskopf ?b=??=1. The maximum and average values of ?b (?bmax, ?bav) and ?? (??max, ??av) were obtained by numerical evaluation, using different inverse power potentials. By introducing these parameters into the approximated formulas for ? and ? using Van der Waals and Lennard-Jones potential, it was found that the results of calculations for (? and ?) with different atomic ...
We present a set of structural parameters for the central parts of 57 early-type galaxies observed with the Planetary Camera of the Hubble Space Telescope. These parameters are based on a new empirical law that successfully characterizes the centers of early type galaxies. This empirical law assumes that the surface brightness profile is a combination of two power laws with different slopes gamma and beta for the inner and outer regions. Conventional structural parameters such as core radius and central surface brightness are replaced by break radius r_b, where the transition between power-law slopes takes place, and surface brightness mu_b at that radius. An additional parameter alpha describes the sharpness of the break. The structural parameters are derived using a chi-squared minimization process applied to the mean surface brightness profiles. The resulting model profiles ...
Production decline-curve analysis is accepted for prediction of future performance of oil and gas wells and fields. One type of decline-curve analysis involves the hyperbolic-decline-curve equation. The challenge with this equation is to determine simultaneously three parameters. The new method creates a computer spreadsheet containing a set of production data. Then, the specific arrangement of cells and columns containing data and/or formulas allows for statistical fits of the data. Finally, setting-up the nonlinear solver allows for optimization of the three parameters by maximization of the square of the regression coefficient. Eight field cases demonstrated the repeatable and rapid curve-fitting of the method.
Bulk properties such as the binding energies, r.m.s. radii and deformation parameters are calculated for the light (Z=2-8) even-mass nuclei using deformed relativistic mean-field theory. A comparison between L1, NL1 and NL2 parameter sets are given. The effects of pairing for open-shell nuclei have been investigated. The calculation is extended to nuclei near the proton- and neutron-drip line. Reasonable agreement with experiment is achieved for NL1 and NL2 parameter sets. (orig.).
Theoretical analysis of the electric field bifurcation is made for the LHD plasma. For given shapes of plasma profiles, a region of bifurcation is obtained in a space of the plasma parameters. In this region of plasma parameters, the electric field domain interface is predicted to appear in the plasma column. The reduction of turbulent transport is expected to occur in the vicinity of the interface, inducing a internal transport barrier. Within this simple model, the plasma with internal barriers is predicted to be realized for the parameters of T{sub e}(0) {approx} 2 keV and n(0) {approx_equal} 10{sup 18} m{sup -3}. (author)
This work reports on the use of three state-of-the-art Monte Carlo codes (MCNPX, PENELOPE, FLUKA) in the efficiency calibration of a Broad-Energy Germanium (BEGe) detector. Initial discrepancies found between the experimental and computational efficiency values are related to the poor knowledge of some physical parameters of the detector (dead-layers, crystal dimensions, etc.). As a consequence, a sensitivity analysis was carried out. Each parameter was systematically analyzed, and an accurate model of the detector was determined. The obtained results are consistent, allowing this model to be used in computational efficiency calibrations of the equipment at stake.
In this paper, it is suggested that the selection method of optimal parameter of power system stabilizer (PSS) with robustness in low frequency oscillation for power system using real variable elitism genetic algorithm (RVEGA). The optimal parameters were selected in the case of power system stabilizer with one lead compensator, and two lead compensator. Also, the frequency responses characteristics of PSS, the system eigenvalues criterion and the dynamic characteristics were considered in the normal load and the heavy load, which proved usefulness of RVEGA compare with Yu's compensator design theory. (author). 20 refs., 15 figs., 8 tabs.
In order to obtain the resonance parameters in a single energy range and the corresponding covariance matrix, a reevaluation of 239Pu was performed with the code SAMMY. The most recent experimental data were analyzed or reanalyzed in the energy range thermal to 2.5 keV. The normalization of the fission cross section data was reconsidered by taking into account the most recent measurements of Weston et al. and Wagemans et al. A full resonance parameter covariance matrix was generated. The method used to obtain realistic uncertainties on the average cross section calculated by SAMMY or other processing codes was examined.
Parameters of permanent magnets result from the combination of intrinsic properties such as saturation magnetization, magnetic exchange, and magnetocrystalline energy, as well as microstructural parameters such as phase structure, grain size, and orientation. Reduction of grain size into nanocrystalline regime (#approx# 50 nm) leads to the enhanced remanence which derives from ferromagnetic exchange coupling between highly refined grains. In this study the fundamental phenomena, quantities, and structure parameters, which define nanophase permanent magnets are presented and discussed. The theoretical considerations are confronted with experimental data for nanocrystalline Sm-Fe-N type permanent magnets. (author)
Based on the single-particle levels given by Nilsson, the intrinsic and effective (with collective effects) level density parameters as a function of the excitation energy for the "1"8"6Os, "1'8"7Ir, "1"8"9Os and "1"9"3Au deformation nuclei have been calculated in the range of the excitation energy up to 150 MeV. The calculated fission probabilities P_f (U) are consistent satisfactorily with the experimental data when a nonadiabatic estimation of the collective effects was used to calculated the nuclear level density parameters.
Each choice of an arbitrary nonzero function f of the four immersion parameters is shown to determine 16N[f] distinguishable classes of two-parameter families of immersions of Einstein-Riemann spacetimes in six-dimensional flat spaces, where N[f] is the number of regular immersion parameter domains. The metric tensors, curvature tensors and the immersion loci are calculated in a closed form, and these calculations involve only finitely many algebraic operations. The presence of the arbitrary function provides the opportunity for study of the behaviour of multiple isolated singularities and/or 'shape' functions in general relativity.
A simple closed-form equation to calculate the envelope correlation between any two receiver or transmitter antennas in a multi-input multi-output (MIMO) system of an arbitrary number of elements is derived. The equation uses the scattering parameters obtained at the antenna feed point to calculate the envelope correlation coefficient. This approach has the advantage that it does not require knowledge of the antenna radiation pattern. Numerical data that include conductor and permittivity loss are shown to validate the approach. Using the scattering parameters for calculating the envelope correlation is less laborious and relatively cheaper, as compared to the radiation pattern approach.
This paper is concerned with the determination of a unique scaling parameter in complex scaling analysis and with accurate calculation of dynamics resonances. In the preceding paper we have presented a theoretical analysis and provided a formalism for dynamical resonance calculations. In this paper we present accurate numerical results for two non-trivial dynamical processes, namely, models of diatomic molecular predissociation and of barrier potential scattering for resonances. The results presented in this paper confirm our theoretical analysis, remove a theoretical ambiguity on determination of the complex scaling parameter, and provide an improved understanding for dynamical resonance calculations in rigged Hilbert space.
We review an analysis of a consistent renormalization of the top and bottom quark/squark sector of the MSSM with complex parameters (cMSSM). Various renormalization schemes are defined, analyzed analytically and tested numerically in the decays Stop_2 -> Sbottom_i H^+/W^+ (i = 1,2). No scheme is found that produces numerically acceptable results over all the cMSSM parameter space, where problems occur mostly already for real parameters. Some numerical examples for Gamma(Stop_2 -> Sbottom_1 H^+) in our preferred scheme, "m_b, A_b DRbar" are shown.
The chemical reaction effect on an unsteady magnetohydrodynamic (MHD) flow past a semi-infinite vertical porous plate with viscous dissipation is analyzed. The governing equations of motion, energy, and species are transformed into ordinary differential equations (ODEs) using the time dependent similarity parameter. The resultant ODEs are then solved numerically by a finite element method. The effects of various parameters on the velocity, temperature, and concentration profiles are presented graphically, and the values of the skin-friction, Nusselt number, and Sherwood number for various values of physical parameters are presented through tables.
The results of an investigation of the effects of several parameters on the reactivity instability of a Boiling Water Reactor (BWR) calculational model are summarized. Calculations were performed for a typical BWR operated at low flow conditions, where reactivity instabilities are more likely to occur. The parameters investigated include the axial power shape (characterized by two separate parameters), the core pressure, and operating flow. All calculations were performed using the LAPUR code which was developed at the Oak Ridge National Laboratory for the dynamic modeling of large BWR's. 4 refs., 8 figs.
Some properties of the universe are fixed by physics derived from mathematical symmetries, others may have been selected from an ensemble of possibilities. Some successes and failures of anthropic reasoning in this context are reviewed in the light of recent developments in astrobiology, cosmology and unification physics. Specific issues raised include our spacetime location (including the reason for the present age of the universe), the timescale of biological evolution, the tuning of global cosmological parameters, the origin of the Large Numbers of astrophysics, and the parameters of the Standard Model. Out of the twenty parameters of the Standard Model,the basic behavior and structures of the world (nucleons, nuclei,atoms, molecules, planets, stars, galaxies) depend mainly on five of them: $m_e,m_u,m_d,\\alpha,\\alpha_G$, three of which are independent in the context of Grand Unified Theories (that is, not related by ...
We investigate the solar neutrino problem in the scenario of three generation neutrino oscillation hypothesis, taking into account other phenomenological constraints to the neutrino mixing and mass parameters.
The double diffusive convection in a horizontal couple stress fluid saturated anisotropic porous layer, which is heated and salted from below, is studied analytically. The modified Darcy equation that includes the time derivative term is used to model the momentum equation. The critical Rayleigh number, wavenumber for stationary and oscillatory modes, and frequency of oscillations are obtained analytically using linear theory. The effect of anisotropy parameter, solute Rayleigh number, Lewis number, couple stress parameter, and Vadasz number on the stationary, oscillatory, and finite amplitude convection is shown graphically. It is found that the thermal anisotropy parameter, couple stress parameter, and solute Rayleigh number have stabilizing effect on the stationary, oscillatory, and fin...
This paper first introduces the calculating method of radium specific activity to determine the radon emanation rate of tailing of uranium mine No. 794, the method needs two parameters: radon emanation coefficient and radon diffusion coefficient. According to the measured results of parameters and the contrast between radium specific activity of indoor chemical analysis of field sample and field gamma-ray spectra, the authors discuss the variation rules and characteristics of radon emanation coefficient and radon diffusion coefficient, and the best climate and seasons for measuring these parameters in northern China, and finally summarize the characteristics of this method through analyzing measured results. (authors)
The theoretical formula for the statistical error estimation in Mihalczo method was derived, and the dependence of the error were investigated on the facility to be measured and on the parameter in the data analysis. The formula was derived based on the reactor noise theory and the error theory for the frequency analysis, and found that the error depends on such parameters as the prompt neutron decay constant, detector efficiencies, and the frequency bandwidth. Statistical errors estimated with the formula was compared with experimental values and verified to be reasonable. Through parameter surveys, it is found that there is an optimum combination of the parameters to reduce the magnitude of the errors. In the experiment performed in DCA subcriticality measurement facility, it is estimated experimentally that the measurement requires 20 minutes to obtain the statistic error of 1% for the keff 0.9. ...
This paper is devoted to the coordination of secondary voltage control and adaptive parameters resetting of the power system stabilizer, in order to increase stability, margins in real time operation. Secondary voltage control and the power system stabilizer are two control loops, which affect the same system parameter on different bases - that parameter is the voltage set-point of the automatic voltage regulator. It was found that their effects were complementary. In that way, through the proper coordination of actions of these two control loops open up a wide range of possibilities for ensuring the stability of bulk power systems in real time. For the establishment of this coordination, an on-line sequential algorithm is proposed which is based on adaptive resetting of the voltage set-point of the automatic voltage regulator and the PSS parameters. The efficiency of the proposed algorithm is confined ...
Computer-Aided Prediction of Chemical Ecotoxicity on the basis of Quantitative Structure-Activity Relationships with the Use of Physico-Chemical Descriptors, Including H-bond Parameters
... Finally, the one dimensional, one phase Stefan problem is well known as a model for the melting of ice (see, eg, [5]). There are many approaches to ...
Application of an optimization technique to extract the non-ideal parameters of gas absorption with chemical reactions process was described. The gas absorption was modeled using mass transfer theory to represent the realistic behaviors of an absorber. The model was a highly non-linear iterative model which correlated the overall rate of absorption as the function of unknown non-ideal parameters, including the physical liquid mass transfer coefficient and the wetted interfacial area of of packings. The optimization program was developed to minimize the sum of squares of relative errors between the model predictions and the experimental data. Four sets of experimental data (case studies) with different operating conditions were used for extracting parameters. Comparisons between predicted and experimental measured overall absorption rate were in good agreement, average absolute value of relative errors not exceeding 5.4 %. ...
The identification of the unknown parameters of the Duffing's mechanical system, based on an algebraic approach, is presented. This approach is fast, accurate, and simple to numerically implement. Also, the method, combined with a suitable invariant filter, can became robust against high frequency output measurement noises. Our method uses the availability of one measurable output and produces an exact formula for the unknown parameters, which may be realized in terms of iterated convolutions. First, we show that the Duffing's system parameters are linearly identifiable with respect to the position variable, then we obtain a linear system where the unknowns are the unavailable parameters. Suitable algebraic operations on the output differential equations makes the identification schema independent of the unavailable initial conditions of the underlying nonlinear dynamical system.
To represent a heterogeneous unsaturated fractured rock by its homogeneous equivalent, Monte Carlo simulations are used to obtain upscaled (effective) flow properties. In this study, we present a numerical procedure for upscaling the van Genuchten parameters of unsaturated fractured rocks by conducting Monte Carlo simulations of the unsaturated flow in a domain under gravity-dominated regime. The simulation domain can be chosen as the scale of block size in the field-scale modeling. The effective conductivity is computed from the steady-state flux at the lower boundary and plotted as a function of the averaging pressure head or saturation over the domain. The scatter plot is then fitted using van Genuchten model and three parameters, i.e., the saturated conductivity K{sub s}, the air-entry parameter {alpha}, the pore-size distribution parameter n, corresponding to this model are considered as the ...
coupled heat/mass transfer Stefan problem. Taking the diffusion coefficient of Bi as a free parameter, the best fit was observed for the published value, ...
Dampfturbinen bei hohen Dampfparametern [Study of shaft seals for steam turbines under high steam parameters],. Maschinenbautechnik L5, 27-31 (1966)0 ...
The error estimation for calculated quantities relies on nuclear data uncertainty information available in the basic nuclear data libraries such as the U.S. Evaluated Nuclear Data File (ENDF/B). The uncertainty files (covariance matrices) in the ENDF/B library are generally obtained from analysis of experimental data. In the resonance region, the computer code SAMMY is used for analyses of experimental data and generation of resonance parameters. In addition to resonance parameters evaluation, SAMMY also generates resonance parameter covariance matrices (RPCM). SAMMY uses the generalized least-squares formalism (Bayes' method) together with the resonance formalism (R-matrix theory) for analysis of experimental data. Two approaches are available for creation of resonance-parameter covariance data. (1) During the data-evaluation process, SAMMY generates both a set of resonance ...
ObjectiveThe purpose of this study was to characterize the sensorineural hearing losses of a group of children and adults along three parameters important to the...Full Text Available
Research on hematological disorders relies on suitable animal models. We retrospectively evaluated the use of the hematological parameters hematocrit (HCT), hemoglobin (HGB), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), mean corpuscular volume (MCV), red blood cell count (RBC), white blood cell count (WBC), and platelet count (PLT) in the phenotype-driven Munich N-ethyl-N-nitrosourea (ENU) mouse mutagenesis project as parameters for the generation of novel animal models for human diseases. The analysis was carried out on more than 16,000 G1 and G3 offspring of chemically mutagenized inbred C3H mice to detect dominant and recessive mutations leading to deviations in the levels of the chosen parameters. Identification of animals exhibiting altered valu...
Immunomodulation by environmental chemical contaminants and the role immune parameters play in toxicity and risk assessment studies is of increasing concern. Although considerable evidence has indicated...Full Text Available
... The third series used a correlated parameter covariance matrix derived from a generic database of modeling uncertainty for space structures [5-1 ...
Hydrous pyrolysis of immature Monterey Phosphatic or Siliceous rock at progressively higher temperatures causes systematic changes in biomarker thermal maturity parameters of the generated hydrocarbons. Biomarker ratios based on proposed carbon-carbon cracking or aromatization reactions increase during hydrous pyrolysis along similar pathways for both Siliceous and Phosphatic members. An increase in these biomarker ratios is also observed for oils of increasing thermal maturity from the offshore Santa Maria Basin, although the rates of changes for each parameter differ between the hydrous pyrolysis and natural samples. Changes in some cracking parameters during maturation appear to result from differential thermal stability of the compounds rather than conversion of precursors to products. (author).
X-ray diffraction offers a unique combination of advantages for kinetic study which include the non-destructive nature of the measurement, the use of bulk crystals, and the convenience of the experimental arrangements. These attributes and the availability of position-sensitive detectors and high-flux synchrotron radiation sources make this technique most useful for in situ, dynamical investigations. When using diffraction techniques to determine a diffusion coefficient, the principle of analysis entails a scattering theory and a kinetic model. The former allows the kinetic parameter(s) to be extracted from measured intensity, while the latter relates the kinetic parameter(s) to the diffusion coefficient(s). Three examples are demonstrated: (1) Palladium Silicide (Pd{sub 2}Si) Layer Growth on Silicon, (2) Decomposition of an Ni-12.5at%Si Superalloy, and (3) Short-range Ordering in Cu-Au Solid Solutions.
Dosimetry parameters such as deposition, clearance, retention, and translocation and dissolution of inhaled particles in and to different lung compartments may be important for the persistence of particles...Full Text Available
In this paper the concept of a composite power system stabilizer is investigated. This stabilizer comprises a properly designed, robust, conventional power system stabilizer (CPSS) and an auxiliary stabilizer (AS) which can be either a self-tuning stabilizer (ASTS) or a fixed-parameter stabilizer (AFPS). For small disturbances, the CPSS performs satisfactorily over a wide range of operating conditions. When large disturbances occur the auxiliary stabilizer augments the performance of the CPSS. It has been demonstrated that the composite power system stabilizer can significantly improve the dynamic performance of the system when there is a major disturbance such as a short circuit in the system. Because in the case of a single-machine system the parameters of the ASTS do not vary appreciably, it can also be implemented as a fixed-parameter device; this simplifies significantly the implementation of the composite PSS. ...
A comparative study of three methods for extracting solar cell parameters of the single-diode lumped-circuit model is presented, using experimental characteristics collected from two silicon cells over a range of illuminations and temperatures. The results show that the curve-fitting method can often give erroneous parameter values. The 5-point methods are found to be reliable and accurate in situations where the model is a good approximation of cell performance. The analytical 5-point method, however, has the added advantage of simplicity. It is also found that for the cell measured, the single diode model is valid at illuminations above one-half AM1 but gives non-physical parameter values at lower illumination.
The aim of this study is to develop the methodology which enables to identify the mechanical properties of element such as stress intensity factor by using the AE parameters. Considering the multivariate and nonlinear properties of AE parameters such as ringdown count, rise time, energy, event duration and peak amplitude from fatigue cracks of machine element the principal component regression(PCR) and artificial neural network(ANN) models for the estimation of stress intensity factor were developed and validated. The AE parameters were found to be very significant to estimate the stress intensity factor. Since the statistical values including correlation coefficients, standard mr of calibration, standard error of prediction and bias were stable, the PCR and ANN models for stress intensity factor were very robust. The performance of ANN model for unknown data of stress intensity factor was better than that of PCR model
... which may have embedded remote terminals, and (4 ... model the time-variant or stochastic aspects of ... on such system parameters as queue size, time ...
This contribution deals with identification of fractional-order dynamical systems. System identification, which refers to estimation of process parameters, is a necessity in control theory. Real processes are usually of fractional order as opposed to the ideal integral order models. A simple and elegant scheme of estimating the parameters for such a fractional order process is proposed. This method employs fractional calculus theory to find equations relating the parameters that are to be estimated, and then estimates the process parameters after solving the simultaneous equations. The said simultaneous equations are generated and updated using particle swarm optimization (PSO) technique, the fitness function being the sum of squared deviations from the actual set of observations. The data used for the calculations are intentionally corrupted to simulate real-life conditions. Results show that the ...
Single-dose and repeated dose toxicity studies of prulifloxacin, a new antibacterial agent, were conducted in aged beagle dogs. I. A single-dose toxicity study Prulifloxacin was administered orally to aged female dogs at a single dose of 2500 and 5000 mg/kg. No death occurred in any group. Vomiting was observed in one of two animals at 2500 mg/kg and in both animals at 5000 mg/kg 3-4 hr after dosing. At 5000 mg/kg, vomiting was observed in both animals after feeding on the day after dosing. One animal also showed soft stool. Thereafter, no abnormalities were observed in any animal. No test article related changes were noted in food consumption, water consumption, body weight or pathological examination in any group. The results show that the lethal dose of prulifloxacin is judged to be greater than 5000 mg/kg in aged female dogs. II. A repeated dose toxicity study Aged male and female dogs were given the test article orally for 4 weeks at doses of 0 (control), 20, 100 and 500 mg/kg. No ...
Primary malignant lymphoma of the brain is a disease of unknown etiology, which is increasing in incidence and has an unfavorable prognosis. Despite the lack of specific changes on CT or MRI in most cases, these procedures may typically facilitate the diagnosis: A focal-enhancing mass with subependymal spread on CT or MRI and hyperattenuation on nonenhanced CT are the most reliable features in the diagnosis of primary malignant lymphoma of the brain. Peritumoral edema and mass effect are usually not prominent features. On unenhanced CT scans they usually appear homogeneously isodense to mildly hyperdense relative to the gray matter. On MRI these tumors are slightly hypointense on T1-weighted images and slightly hpyerintense on PD- and T2-weighted images relative to the gray matter. On CT and MRI enhancement is usually homogeneous. Contrast-enhanced MRI, with its multiplanar capability, lack of bone-induced artifacts, and high-contrast resolution, is likely to ...
Penetrating liver wounds are related to many causes and rank second after blunt abdominal and liver trauma. In this report are examined the clinical and radiological findings of personal series of patients with penetrating trauma, especially by firearms and stab and cut wounds. It will also tried to define the diagnostic workup of these traumas, which is especially based on CT signs of liver damage and associated changes and which is of basic importance for following treatment, both surgical or conservative. In the last seven years it was retrospectively reviewed 31 cases of penetrating liver trauma. The patients were 19 men and 12 women, ranging in age 18 to 73 (mean 42), with penetrating liver injuries from firearms (16 patients) and stab (9 cases) wounds; 6 patients had injuries from different cases. Abdominal CT was carried out in emergency with the CT Angiography (CTA) technique in all patients. In the patients with suspected chest and abdomen involvement CT was performed from the ...
For heavy-ion beam driven inertial fusion ''liquid-protected'' reactor designs such as HYLIFE-II, a mixture of molten salts made of F{sup 10}, Li{sup -6}, Li{sup 7} and Be{sup 9} (called flibe) allows small chambers and final-focus magnets closer to the target with superconducting coils suffering higher radiation damage, though they can stand only a certain amount of energy deposited before quenching. This work has been primarily focusing on verifying that total energy deposited by fusion neutrons and induced gamma rays remain under such limit values and the final purpose is the optimization of the shielding of the magnetic lens system from the points of view of the geometrical configuration and of the physical nature of the materials adopted. The system is analyzed in terms of six geometrical models going from simplified up to much more realistic representations of a system of 192 beam lines, each focused by six magnets. A 3-D transport calculation ...
The electrogeometric model cannot consider the influence of some parameters on the screening of the wire conductor of the H.V. lines. For analysing the influence of these parameters (the conductor potential, the influence of the distance from phase conductor to earth wire, the influence of the reducing factor of the striking earth distance, the earth slope, etc.), the Monte Carlo method is preferable. The influence of the earth slope on the screening effect of the wire conductor for different conditions is presented in this paper. (author)
The necessity of the electron beam machine characterization via dose measurement is discussed. It includes a measurement of comprehensive dose distribution (at known X and Z axis) for verification of the machine performance. The acquired data were then used to develop the irradiation parameters such as energy, current, distance, conveyor speed, exposure rate and depth inside product to be irradiated. These parameters will be used as a guide for the routine irradiations. (Author)
BackgroundThe association between infertility and sperm disomy is well documented. Results vary but most report that men with severely compromised semen parameters have a significantly...Full Text Available
An original method is proposed for ensuring time-invariant (stationary) interior ballistic parameters in the postprojectile space of a gun barrel. Stationarity of the parameters is achieved by investing the solid-propellant charge with highly original structures that produce the required pressure condition and linear growth of the projectile velocity. Simple relations are obtained for calculating the principal characteristics.
From the numbers of radiographs of the different examinations and the total amount of radiological diagnostics in the GDR their possible modification by new imaging techniques is discussed under the aspects of costs and radiation burden. Film-screen-systems are of special importance, because they also will be most frequently used image recording system in future. The importance of their various properties and parameters, methods of determining these parameters as well as future developments are analyzed from the standpoint of practical requirements.
From the numbers of radiographs of the different examinations and the total amount of radiological diagnostics in the GDR their possible modification by new imaging techniques is discussed under the aspects of costs and radiation burden. Film-screen-systems are of special importance, because they also will be most frequently used image recording system in future. The importance of their various properties and parameters, methods of determining these parameters as well as future developments are analyzed from the standpoint of practical requirements. (author).
In this note we prove to all orders in the small scale expansion that all off-shell parameters which appear in the chiral effective Lagrangian with explicit DELTA(1232) isobar degrees of freedom can be absorbed into redefinitions of certain low-energy constants and are therefore redundant.
An original evaluating method of gain degradation has been found for neutron irradiated transistors. It establishes a correlation between degradation and the product of two coefficients: spectra factor and an electrical parameter which is measured or directly deduced from manufacturer's data. Equivalence for several type of spectra (fission, 14MeV and degradation sensitivity to electrical parameters values of individual components of a batch are obtained.
The magnetic #beta#-spectrometer of the #pi# #sq root#2 type with 0.07% pulse resolution is used to measure the intensities of interval conversion electrons on L- and M-subshells of 70.45 keV "1"7"7 Ta gamma-transition. The results are analyzed and the values of mixing parameter #sigma#(E2/M1) and penetration parameter #lambda# are obtained.
This work presents a method to monitor the stability of a power system, after a major disturbance, using of adaptive time series approach. The model parameters are updated every time the prediction stage is completed. Besides, according to the values of the parameters, one may conclude the system will be unstable, will go to be a damped sine wave or even a damped exponential. (author) 29 refs., 12 figs., 3 tabs.
X-ray results on the lattice parameters, molar volume and thermal expansion coefficients of solid ortho-deuterium for the region from 2 K to the melting point are reported. It is found that the thermal expansion of ortho-deuterium crystals, similarly to parahydrogen is essentially anisotropic near the melting temperature. The vacancy density at the triple point is estimated. Some thermodynamic characteristics of ortho-deuterium are calculated and temperature dependences of heat capacity at constant volume, isothermal compressibility and Gruneisen constant are analyzed.
Experimentally it is found that at constant temperature the order-parameter relaxation time, tausub(..delta..), decreases with increasing power of the microwaves, coupled into a superconducting strip. If the same increase in critical current, that corresponds with a given power of the microwaves, is obtained by lowering the temperature, the decrease in tausub(..delta..) is smaller. This reflects the fact that quasiparticles are removed more efficiently from the gap edge by microwaves than by lowering the temperature in equilibrium. A modified time-dependent Ginzburg-Landau equation is shown to describe these results adequately.
In this article carbon co-implantation and step-by-step thermal treatments of shallow p"+-n-junctions formation were used with the purpose of extended defect suppression and reduction of boron transient enhanced diffusion. A substantial improvement of the structural and electrical parameters of shallow p"+-n-junctions has been achieved by using the additional carbon implantation and step-by-step thermal treatments. (authors)
The Grueneisen parameter and lattice thermal expansion of the A-15 compounds V_3Si and V_3Ge at room temperature are evaluated on the basis of the method due to Brugger and Fritz from the third order elastic constants reported earlier. The calculated values are compared with available experimental values and are found to fit satisfactorily. (author).
Experimental and evaluated integral parameters derived from nuclear plus interference differential elastic scattering cross sections are presented for all projectile/target combinations of the particles p, d, t, /sup 3/He, and ..cap alpha... The data include reaction rates, average fractional energy losses per collision and per unit path length, and average laboratory scattering cosines. The resulting parameters are of potential use in analysis of charged-particle transport.
The electron structure of the A-15 compounds is studied by accounting for the Hubbard energy as the highest energy parameter. The conditions for the Cooper instability origination are obtained. The superconducting transition temperature dependence on the degree of filling the d- and p-shells of the transition and nontransition elements is determined. The relationship between the transition temperature and the energy jumpover along the chains, which allows comparison with the experiment, is established. Qualitative explanation of the Mattias empiric rules is presented
In this paper, aluminium nitride synthesis is carried out by direct laser irradiation onto an aluminium target surface in a nitrogen containing atmosphere. The influence of various processing parameters on the microstructure of AlN thin films is investigated in order to improve their tribological properties. The main microstructural characteristics: nature, concentration, in depth distribution and morphology of various phases are studied versus processing parameters by TEM and GIXD. (author). 2 refs., 1 fig., 2 photos.
In this paper, aluminium nitride synthesis is carried out by direct laser irradiation onto an aluminium target surface in a nitrogen containing atmosphere. The influence of various processing parameters on the microstructure of AlN thin films is investigated in order to improve their tribological properties. The main microstructural characteristics: nature, concentration, in depth distribution and morphology of various phases are studied versus processing parameters by TEM and GIXD. (author). 2 refs., 1 fig., 2 photos.
In this work dissipativity of linear neutral distributed parameter systems has been addressed. Delay-dependent sufficient conditions for the dissipativity with respect to the infinite-dimensional version of energy supply rate (Q"1,S"1,R"1) characterized exclusively by unbounded operator Q"1 are established in terms of linear operator inequalities (LOIs). Finally, the 3-dimensional heat equation illustrates our result.
Differences of the deformation parameters for the 2"+_1 states of even-even spherical nuclei extracted from electromagnetic excitation #beta#sup(em)_2 and from proton scattering #beta#sup(pp')_2 are discussed. It is found that the ratio #beta#sup(pp')_2/#beta#sup(em)_2 is equal to about unity and that there is a small isotope dependence for several incomplete shell nuclei. (orig.).
Four solutions of the Cauchy problem for Mathieu?s equation away from parametric resonance domains are analytically constructed using an asymptotic averaging method in the fourth approximation. Three solutions occur near fractional parameter values at which slow combination phases exist. The fourth solution occurs in the absence of slow phases away from parametric resonance domains and the fractional parameter values.
A computer program 'CPA simulator' has been designed to simulate the response parameters of a typical charge preamplifier (CPA) used in nuclear front-end electronics. The response parameters are studied considering three common connection methods between the detector and the CPA. The simulator predicts and illustrates the role and influence of the different components of the CPA and detector circuits.
The object of this paper is to show how the profile of metal concentration in the soil near bone from archaeological sites can be used, along with the appropriate mathematical model, to extract transport parameters. These parameters can then be used to predict long-term migration rates of chemical species associated with the burial of hazardous wastes in similar environmental settings.
In this paper the robust stability analysis of a single machine infinite bus system is investigated using interval matrix theory. Specifically the parameters of the power system stabilizer are considered as uncertainties in the system A matrix. The range of these parameters for which the system is Hurwitz stable is then found using interval matrix theory. (Author)
A computerised curve-fitting method was developed to calculate the trapping parameters in LiF TLD-100 and LiF:Mg, Ti. After irradiation in a "6"0Co field and with X rays emitted at different voltages the TL process is best described by first-order kinetics. A dependence of the trapping parameters on both the concentration of Mg and Ti and photon energy was detected. (author).
Acoustic waves propagation of in composite of water with embedded double-layered silicone resin/silver rods is considered. Approximate values of effective dynamical constitutive parameters are obtained. Frequency ranges of simultaneous negative constitutive parameters are found. Localized surface states on the interface between metamaterial and ``normal'' material are found. Doppler effect in metamaterial is considered. Presence of anomalous modes is shown.
In this paper a phenomenological analysis of the sintering kinetics of alumina powder compacts with different proportions of small and large particles has been made. A phenomenological approach enables definition of functional connections between parameters characteristic of a certain material and the sintering time. A phenomenological equation is defined, which can be used to describe the densification process of alumina during isothermal sintering. Its parameters enable identification of the dominant diffusion mechanism. (orig.)
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 ...
There is currently considerable interest in identifying and quantifying the effects of welding procedure parameters and steel composition factors on the risk of cracking in pipeline girth welds that may be experienced during winter construction. Although low ambient temperatures, that may be experienced during winter construction, are generally assumed to increase the risk of cracking there has been little work to quantify the effects and to suggest how welding procedures should be modified for winter conditions. The present work was undertaken to calculate the effects of changes in welding parameters on the thermal cycle and the diffusion of hydrogen for a typical pipeline girth weld. A simple analytical method and the finite element method (FEM) were used. Both methods gave similar results but the simple method was very sensitive to the value of heat transfer coefficient. The results showed that the relation between the hydrogen diffusion ...
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 ...
This paper presents a nonlinear Bayesian regression algorithm for the purpose of detecting and estimating gas plume content from hyper-spectral data. Remote sensing data, by its very nature, is collected under less controlled conditions than laboratory data. As a result, the physics-based model that is used to describe the relationship between the observed remotesensing spectra, and the terrestrial (or atmospheric) parameters that we desire to estimate, is typically littered with many unknown "nuisance" parameters (parameters that we are not interested in estimating, but also appear in the model). Bayesian methods are well-suited for this context as they automatically incorporate the uncertainties associated with all nuisance parameters into the error estimates of the parameters of interest. The nonlinear Bayesian regression methodology is illustrated on realistic simulated data ...
The generation of a defined swivel momentum in car door hinges depends on numerous constructional and technical manufacturing parameters. If these parameters and their influence are to be investigated, then in addition to detailed experiments with variations in the parameters, methods are also required which enable the measuring data produced to be assessed in such a way that, in general, the non-linear relationships between initial and target size can be described sufficiently accurately. This paper explains the parameter reduction necessary in the experimental investigation, gives the results of the data assessment with conventional statistical methods and describes in particular the use of artificial neural networks (ANN) to construct so-called 'neuro hinge models' on the basis of the data resulting from the experiments. Parameter variations can be simulated ...
The effects of neutron irradiation on the superconducting and normal state properties of alloys and compounds are presented. Particular emphasis is placed on the A-15 compounds where the effects of neutron irradiation on Tsub(c), Hsub(c_2), long range order parameter and lattice parameter are described. Large depressions (up to 80%) in Tsub(c) are observed for all the A-15 compounds studied with the exception of Mo_3Os where much smaller decreases in Tsub(c) are seen. Along with the decrease in Tsub(c) and increase in lattice parameter, the degree of long range order, as measured by X-ray and neutron diffraction, decreases. Also presented are the results of isothermal and isochronal anneals up to 900"0C. The unirradiated value of Tsub(c) can be restored by annealing, and for those systems where measurements have been made, recovery of the lattice parameter and order parameter also ...
A detailed outline of the application of the MELCOR and RELAP5/MOD3.1 codes to the analysis of the thermohydraulic response and determination of other parameters of the medium on the floor is given for several classes of secondary coolant circuit accidents along with the description of the related facilities. An overview is presented of the maximum values and time behavior of the thermohydraulic parameters, pressure, temperature, relative humidity, and water level on the floor. Transverse rupture of the steam generator, main steam header, or main feedwater header piping during normal operation is considered as the initiating event. Pressure is only 10% higher than the atmospheric pressure. Air temperature attains a value as high as 100 degC. Relative humidity is 100%, persisting as long as the steam source is available. The water level is typically about 8 cm and never exceeds 15 cm. (M.D.). 16 tabs., 37 figs., 32 refs.
We present a comprehensive, up-to-date compilation of band parameters for the technologically important III - V zinc blende and wurtzite compound semiconductors: GaAs, GaSb, GaP, GaN, AlAs, AlSb, AlP, AlN, InAs, InSb, InP, and InN, along with their ternary and quaternary alloys. Based on a review of the existing literature, complete and consistent parameter sets are given for all materials. Emphasizing the quantities required for band structure calculations, we tabulate the direct and indirect energy gaps, spin-orbit, and crystal-field splittings, alloy bowing parameters, effective masses for electrons, heavy, light, and split-off holes, Luttinger parameters, interband momentum matrix elements, and deformation potentials, including temperature and alloy-composition dependences where available. Heterostructure band offsets are also given, on an absolute scale that allows any material to be aligned ...
In this study, adjoint sensitivity theory is developed for equations of two-dimensional steady-state flow in a confined aquifer. Both the primary flow equation and the adjoint sensitivity equation are solved using the Galerkin finite element method. The developed computer code is used to investigate the regional flow parameters of the Leadville Formation of the Paradox Basin in Utah and the Wolcamp carbonate/sandstone aquifer of the Palo Duro Basin in the Texas Panhandle. Two performance measures are evaluated, local heads and velocity in the vicinity of potential high-level nuclear waste repositories. The results illustrate the sensitivity of calculated local heads to the boundary conditions. Local velocity-related performance measures are more sensitive to hydraulic conductivities. The uncertainty in the performance measure is a function of the parameter sensitivity, parameter variance and the correlation between ...
A doubly Q-switched laser with both an acousto-optic (AO) modulator and a GaAs saturable absorber can obtain a more symmetric and shorter pulse with high pulse peak power, which has been experimentally proved. The key parameters of an optimally coupled doubly Q-switched laser with both an AO modulator and a GaAs saturable absorber are determined, and a group of general curves are generated for what we believe is the first time, when the single-photon absorption (SPA) and two-photon absorption (TPA) processes of GaAs are combined, and the Gaussian spatial distributions of the intracavity photon density and the initial population-inversion density as well as the influence of the AO Q-switch are considered. These key parameters include the optimal normalized coupling parameter, the optimal normalized GaAs saturable absorber parameters, and the normalized parameters of the AO Q-switch, ...
The optical spectra of actinide ions in the compound AnCl_3 and doped into single crystal LaCl_3 were interpreted in terms of transitions within 5f"N configurations. Energy-level calculations were carried out using an effective operator Hamiltonian, the parameters of which were determined by fitting experimental data. Atomic and crystal-field matrices were diagonalized simultaneously assuming an approximate D_3_h site symmetry. The spectroscopic data were taken from the literature but in most cases supplemented by unpublished measurements in absorption and in fluorescence. Spectroscopic data for each ion were analyzed independently, then the model parameters were intercompared and in many cases adjusted such that in the final fitting process the principal interactions showed uniform trends in parameter values with increasing atomic number. Consistent with analyses of the spectra of lanthanide ions in both LaCl_3 and LaF_3, ...
The function of the hypothalamo-pituitary-gonadal system has been studied in 118 males with different stages of alcoholism. Comparison with the control group has shown decreased levels of interstitial cell stimulating hormone (ICSH), follicle-stimulating hormone (FSH), and testosterone, and elevated concentrations of prolactin (Prl). Differences in the parameters of hormonal activity expressed in a varying degree of a decrease in FSH, ICSH, and testosterone, and a Prl elevation are related to change in mutual regulatory influences between the gonads and hypothalamo-pituitary complex. The most informative parameters were concentrations of Prl and testosterone (considering elevation in the former and reduction in the latter hormone) and the ratio of their concentrations. Difference of these parameters in each group (corresponding to the stages of alcoholism) may be used as an additional diagnostic criterion of chronic alcohol ...
We examined the spectral behaviors of lasing from a asymmetrically deformed liquid jet (a ? 14 ?m) which is induced by a laterally flowing gas. Th liquid sample was methanols which contains DCM dye. When n distortion is induced, the lasing spectrum appears as two periodic peaks which are corresponding to the resonance modes of cylindrical cavity. As the distortion parameter exceeds about 4%, the lasing spectrum shifts continuously to short wavelength. When the distortion parameter reaches ? 10%, the amount of blue shift was ? 30 nm. The blue shift can be explained as the shift of optimum wavelength of threshold curves. From the absorption and fluorescence curve of liquid sample, we estimated the spoiled Q with the distortion parameter.
Collaborative Filtering (CF) is a popular method for personalizing product recommendations for e-Commerce and customer relationship management (CRM). CF utilizes the explicit or implicit product evaluation ratings of customers to develop personalized recommendations. However, there has been no in-depth investigation of the parameters of CF in relation to the number of ratings on the part of an individual customer and the total number of ratings for an item. We empirically investigated the relationships between these two parameters and CF performance, using two publicly available data sets, EachMovie and MovieLens. We conducted three experiments. The first two investigated the relationship between a particular customer?s number of ratings and CF recommendation performance. The third experim...
The analysis of elastic and inelastic scattering of #alpha# particles with energy of 50 MeV by nuclei with mass numbers A=54-124 and of "3He particles by the nucleus "6"4Ni is given in the framework of the optical model. The parameters of multipole deformations for lower states are determined. The parameters for quadrupole and octupole deformations of the potential for the nucleus "1"1"2Sn are extracted, the values of the hexadecupole deformation #beta#_4 of the potential for nuclei "9"4Zr, "1"2"0","1"2"4Sn are found. Information is extracted on the ratio of deformation parameters for the neutron and proton components in lower collective states (2_1"+, 3_1"-) of nuclei with A=90-124.
Investment in mining projects is always associated with risk because of the inclusion of many uncertain parameters. Probability analysis can be applied to such a system which has many kinds of uncertain parameters. This kind of study uses historical data to provide more information for future decisions. This study uses the historical data from a truck-shovel operation at an open cut Coal Mine in NSW, Australia to develop a productivity estimation model, using stochastic analysis. In the first step statistics and various probability distributions were developed for both certain and uncertain variables. A correlation analysis was the next step to investigate any possible relationship between productivity and affecting parameters. The results of these two stages were then used in a simulation model using the stochastic approach. 2 figs.
The optical spectroscopy measurements of gadolinium gallium garnet (GGG) crystals doped with Yb show evidence of the presence of non-equivalent optical centers with very similar radiative decay rates. The energy level schemes of those centers have been determined on the basis of optical absorption, luminescence and Raman experiments. Crystal field fitting resulted in two sets of slightly different crystal field parameters for two non-equivalent Yb centers. Both sets of parameters describe perfectly the experimentally detected Y b3+ energy levels. Correlation between systematic trends in the experimental energy level schemes and crystal field parameters is discussed.
Available in abstract form only. Full text of publication follows: In this study. simulation of carbon dioxide absorption by Sodium Hydroxide solution in a packed bed has been investigated. At first, mass and energy balances were applied around a differential height of the bed. So, the governing equations were obtained. Surface renewal theory by Danckwerts was used to represent the mass transfer operation Finally, by changing the operating parameters like solvent temperature, inlet gas composition pressure and height of the bed, the effect of these parameters on the absorption and the composition of carbon dioxide in exit stream have been investigated. (authors)
Abstract Copper(II) bis(thiosemicarbazone) are very useful for blood flow and hypoxic imaging. The aim of this study was to identify structure-activity relationships (SARs) within a series of analogues with different substitution patterns in the ligands, in order to design improved hypoxia imaging agents and elucidate hypoxia selectivity mechanisms. Genetic algorithms (GAs) were used to develop specific copper metal-ligand force field parameters for the MM3 force-field calculations. These new parameters produced results in good agreement with experiment and previously reported copper metal-ligand parameters. A successful quantitative SAR (QSAR) for predicting the several classes of Cu(II)-chelating ligands was built using a training set of 21 Cu(II) complexes. The QSAR exhibited a correlat...
This report describes all time and frequency analysis parameters measured with the new Nuclear Weapons Identification System (NWIS) processor with three input channels: (1) the {sup 252}Cf source ionization chamber; (2) a detection channel; and (3) a second detection channel for active measurements. An intuitive and physical description of the various functions is given as well as a brief mathematical description and a brief description of how the data are acquired. If the full five channel capability is used, the number of functions increases in number but not in type. The parameters provided by this new NWIS processor can be divided into two general classes: time analysis signatures including multiplicities and frequency analysis signatures. Data from measurements with an 18.75 kg highly enriched uranium (93.2 wt%, {sup 235}U) metal casting for storage are presented to illustrate the various time and frequency analysis ...
This report describes all time and frequency analysis parameters measured with the new Nuclear Weapons Identification System (NWIS) processor with three input channels: (1) the 252Cf source ionization chamber (2) a detection channel; and (3) a second detection channel for active measurements. An intuitive and physical description of the various functions is given as well as a brief mathematical description and a brief description of how the data are acquired. If the fill five channel capability is used, the number of functions increases in number but not in type. The parameters provided by this new NWIS processor can be divided into two general classes: time analysis signatures including multiplicities and frequency analysis signatures. Data from measurements with an 18.75 kg highly enriched uranium (93.2 wt 0/0, 235U) metai casting for storage are presented to illustrate the various time and frequency analysis parameters.
A pipe whip test is one of the main subjects of the pipe rupture tests performed in Japan Atomic Energy Research Institute. In 1979, the pipe whip test of 4B, sch-80 pipe will be done under the BWR condition. As the preliminary analysis of this test, the pipe whip analysis of 4B, sch-80 pipe was implemented in order to make clear of the influences of the physical parameters on the pipe whip behavior. The pipe whip analysis was treated as nonlinear dynamic analysis of pipe-restraint system by using the general purpose finite element program ADINA. Overhang length, clearance between pipe and restraint, restraint length and cross section area of restraint were taken as physical parameters. It was clarified through this analysis how restraint displacement, restraint strain and distribution of energy between pipe and restraint were influenced by these parameters. (author).
Multiple receivers can be utilized to enhance the spatiotemporal resolution of MRI by employing the parallel imaging technique. Previously, we have reported the L-curve Tikhonov regularization technique to mitigate noise amplification resulting from the geometrical correlations between channels in a coil array. Nevertheless, one major disadvantage of regularized image reconstruction is lengthy computational time in regularization parameter estimation. At a fixed noise level, L-curve regularization parameter estimation was also found not to be robust across repetitive measurements, particularly for low signal-to-noise ratio (SNR) acquisitions. Here we report a computationally efficient and robust method to estimate the regularization parameter by partitioning the variance of the noise-white...
Generally the photonic band gap (PBG) is a multi-variable function of several parameters related to the shape and size of the dielectric columns of photonic crystals (PhCs), and a time-consuming step-by-step scanning process for each parameter has to be used to find their best combination yielding maximum PBG. In this letter, the widely used Nelder-Mead simplex algorithm is introduced to optimize these parameters simultaneously to find a larger PBG for a new kind of two-dimensional (2D) hexagonal GaAs-Air PhC. This structure can be conveniently produced by the single-exposure holographic lithography, and the specific holographic design is also systematically investigated. This study reveals that the band gaps of PhCs made by holographic lithography may be widened by introducing irregularity of the columns and lowering the symmetry of the structure.
Metal-organic chemical vapor deposition (MOCVD) made layers of strontium-bismuth-tantalate (SBT) were characterized by spectroscopic ellipsometry (SE) using the Adachi model [S. Adachi, Phys. Rev. B 35 (1987) 7454-7463]. The evaluated optical parameters were correlated with the physical and chemical behavior examined by X-ray diffraction (XRD). As a result, it was possible to fit the measured spectra with the Adachi model in a wide range covering the region of the band gap. The Adachi model provides electronic layer parameters like the transition energy E 0 and broadening ?. Our investigations established a correlation between XRD-determined average grain size and the electronic layer parameters.
The binding energy parameter #lambda# plays an important role in common envelope evolution. Previous works have already pointed out that #lambda# varies throughout the stellar evolution, though it has been adopted as a constant in most of the population synthesis calculations. We have systematically calculated the binding energy parameter #lambda# for both Population I and Population II stars of masses 1-20 M _s_u_n, taking into account the contribution from the internal energy of stellar matter. We present fitting formulae for #lambda# that can be incorporated into future population synthesis investigations. We also briefly discuss the possible applications of the results in binary evolutions.
Nomographs that calculate the threshold values of surface fire parameters which lead to crown fire initiation were created by linking two separate fire behavior models: Van Wagner?s crown fire ignition criteria and Byram?s surface fire model. The nomographs were also based on the existing surface (fuel load, fuel heat content) and canopy (foliar moisture content, live crown base height) fuel models of Aleppo (Pinus halepensis Mill.) pine forests of Mediterranean Greece. The most important fire parameters for crown fire initiation that are calculated by the nomographs are the critical flame length and the forward spread rate of the surface fire. These parameters are readily observable in the field during fires. The nomographs provide a judicious way to assess whether a crown fire is likely ...
Because the state of a free-floating space robot model is uncertain and sudden changes in the model parameters might undermine the stability of the system, this paper proposes a control strategy based on a variable structure neural integrated controller. This scheme does not need a precise space robot model, making use of the radial basis function neural network ability approach to learn about an uncertain model. The network weights are adjusted online in real-time. During the early period of the control phase and parameter changes, the variable structure controller compensates for the uncertain model which the neural network could not learn well. It also creates global asymptotic stability for the whole closed-loop system. Simulation results show that the controller can handle bad changea...
MRI diagnosis for malignant tumors are made possible by direct comparison to the results obtained by the brain and it seems possible to differentiate malignant tumors from other benign lesions. Cystic lesions, and mycotic sinusitis sometimes resemble malignant tumors in MR Image. In the present report, we investigated the relationships between the biochemical contents of cystic lesions and NMR-parameters to clarify why some inflammatory lesions appeared similar to malignant tumors in MRI. The variation of relaxation time depends upon the amount of protein in the cystic contents and the amount of glucose affects the relaxation time. We conclude that NMR-parameters are useful for the differential diagnosis of malignant tumors, cystic lesions and mycositic sinusitis by using the multiple variation analysis.
During the present project the mechanisms of generation of low frequency noise (LFN) for upwind rotors has been investigated. A 3.6 MW turbine has been simulated with a noise prediction model from NASA in US. Running the model on this turbine a number of important turbine design parameters with influence on the LFN have been identified as well as other parameters not linked to the turbine design. Of important parameters can be mentioned 1) rotor rotational speed, 2) blade/tower clearance, 3) rotor configuration - upwind/downwind, 4) unsteadiness/turbulence in inflow. Further, the directivity characteristics of LFN has been computed as well as reduction in noise as function of distance from the turbine. In general low levels of LFN has been computed for the upwind rotor in standard configuration. (au)
A numerical investigation for forced convection in a constant-temperature parallel plate channel with porous cavity and block alternately emplaced on the bottom plate is presented in this work. The Brinkman-Forchheimer-extended Darcy model, which accounts for the effects of impermeable boundary and inertia, is used to characterize the flow field inside the porous region. Solutions of the coupled governing equations are carried out through the stream function-vorticity analysis. The characteristics of fluid flow and forced convection heat transfer have been obtained by the examinations of various governing parameters, such as the Reynolds number, Darcy number, inertial parameter, Prandtl number, and two geometric parameters. Several interesting phenomena such as the heat transfer augmentation in the channel were presented and discussed. The results of this investigation indicate that the size of recirculation caused by ...
The objective of the inspection qualification is to ensure that applied non-destructive methods (NDT) have the required performance. The approach of the qualification process is systematic and carefully documented and therefore some new requirements can be seen concerning the composition of the documentation. There are also new document types, that only application of the inspection qualification requires. The most important of these is the technical justification, that includes the documented evidences concerning the performance of the inspection system. This publication includes two reports: 'Compilation of the inspection procedure' and 'Essential/influential parameters in NDT qualification'. The former of these discusses the issues to be considered in an inspection procedure especially from the point of view of the mechanised ultrasonic testing. The later report explains the parameters formulated to ...
In order to match the output capacity of a geothermal heat pump system (GHPS) with the actual load requirement, research has been carried out in finding the influence of two systematic parameters, the water flow rate inside the condenser and the compressor input frequency on the GHPS operation. Experiments are done on a small-scale GHPS at the water flow rate ranging from 0.054 kg/s to 0.174 kg/s and the frequency from 30 Hz to 55 Hz. The analysis of the experimental data reveals the relationships among the compressor frequency, the water flow rate and other important parameters such as coefficient of performance (COP), heat capacity and compressor power input. The conclusions in the paper can serve as some guidance to the load adjustment of GHPS. (author)
The modeling and optimizing processes of a Ground Coupled Heat Pump (GCHP) with closed Horizontal Ground Heat eXchanger (HGHX) are presented in this paper. After thermal modeling of GCHP including HGHX, the optimum design parameters of the system were estimated by minimizing a defined objective function (total of investment and operation costs) subject to a list of constraints. This procedure was performed applying Genetic Algorithm technique. For given heating/cooling loads and various climatic conditions, the optimum values of saturated temperature/pressure of condenser and evaporator as well as inlet and outlet temperatures of the water source in cooling and heating modes were predicted. Then, for our case study, the design parameters as well as the configuration of HGHX were obtained. Furthermore, the sensitivity analysis of change in the total annual cost of the system and optimum design parameters with the climatic ...
Strong gravitational lensing of an extended object is described by a mapping from source to image coordinates that is nonlinear and cannot generally be inverted analytically. Determining the structure of the source intensity distribution also requires a description of the blurring effect due to a point spread function. This initial study uses an iterative gravitational lens modeling scheme based on the semilinear method to determine the linear parameters (source intensity profile) of a strongly lensed system. Our 'matrix-free' approach avoids construction of the lens and blurring operators while retaining the least squares formulation of the problem. The parameters of an analytical lens model are found through nonlinear optimization by an advanced genetic algorithm (GA) and particle swarm optimizer (PSO). These global optimization routines are designed to explore the parameter space thoroughly, mapping model degeneracies in ...
IntroductionMost clinical studies on the outcome of apical surgery concentrate on periapical healing based on radiographic and clinical characteristics (signs and symptoms). This study focuses on long-term changes in periodontal parameters after apical surgery. MethodsPeriodontal parameters (ie, probing depth [PD], level of gingival margin [GM], and calculated clinical attachment level [CAL]) were collected at baseline and at 1 and 5 years after apical surgery. Changes in PD, GM, and CAL were calculated over time and were also evaluated in relation to patient-, tooth-, and treatment-related covariables. ResultsOne hundred eighty-six of 242 initially identified teeth could be evaluated. Significant changes in GM and CAL were observed at facial sites during the first year after surgery (mean...
Experience with the identification and tuning of exciter constants for a generating unit as the Second Nuclear Power Plant of Taiwan Power Company is reported. Field test is first performed on the excitation system with the generator open-circuited. Since the field test results differ from the computer simulation results using manufacturer`s constants, the authors first modify the manufacturer`s constants based on their previous experience to reach a preliminary set of parameters for the excitation system. Then a hybrid nonlinear simulation-sensitivity matrix method is developed to further refine the excitation system parameters. The exciter constants are tuned in order to give better dynamic response before a power system stabilizer is applied to the generator. Field tests are then performed in order to compare the dynamic response of the generator without and with power system stabilizer.
Experience with the identification and tuning of exciter constants for a generating unit as the Second Nuclear Power Plant of Taiwan Power Company is reported. Field test is first performed on the excitation system with the generator open-circuited. Since the field test results differ from the computer simulation results using manufacturer's constants, the authors first modify the manufacturer's constants based on their previous experience to reach a preliminary set of parameters for the excitation system. Then a hybrid nonlinear simulation-sensitivity matrix method is developed to further refine the excitation system parameters. The exciter constants are tuned in order to give better dynamic response before a power system stabilizer is applied to the generator. Field tests are then performed in order to compare the dynamic response of the generator without and with power system stabilizer.
In this study, ethanol organosolv pretreatment was investigated and optimized for the pretreatment of empty palm fruit bunch using (1) response surface methodology based on three-variable central composite design and (2) the combined severity parameters. The reaction parameters studied were sulfuric acid concentration (0.5-2.0%), reaction temperature (160-200^oC) and residence time (45-90min). Both models provide valuable and complementary informations: using combined severity parameters, very good predictions were obtained concerning xylan and lignin extraction whereas central composite design is the best model for glucose production. The optimal values of the variables were as the followings: sulfuric acid 2.0% w/w, 160^oC, 78min and the experimental values (96.0%) concerning glucose and...
The absorption spectra of an unoriented single crystal of the title compound (1) have been measured at room and at low temperatures. Assuming a similar sequence of crystal field (CF) levels as for the previously analyzed Nd[N(SiMe_3)_2]_3 (2) a truncated CF splitting pattern is derived from the spectra obtained. The parameters of an empirical Hamiltonian are fitted to the energies of 71 levels to give an r.m.s. deviation of 24.2 cm"-"1. The parameters obtained are compared with those of 2 and Nd[N(SiMe_3)_2]_3(CNC_6H_1_1)_2 (3). The observed trends of CF parameters are consistent with the results of simple model calculations in the framework of the angular overlap model. (orig.)
Due to the advantages of the flexibility and economics in exploration and production of offshore liquefied natural gas (LNG), the floating production storage and offloading unit for liquefied natural gas (LNG-FPSO) has attracted wide attentions in recent years. The offloading system for LNG transportation from LNG-FPSO to LNG carrier is one of the most important parts in LNG-FPSO. The influences of the main parameters such as the mass flow rate and the height difference of the pipeline. on the performance of LNG offloading in offshore associated gas fields were investigated. A model based on a typical offshore LNG offloading system was first established and simulations were conducted. The governing equations were then used to evaluate the effects of parameters together with the simulation ...
Effect of globular structure parameters - size of primary #alpha#-phase particles (bsub(I)), thickness and amount of plates of secondary #alpha#-phase (bsub(II), #gamma#sub(II#alpha# )) - on a complex of mechanical properties (#sigma#sub(#beta#), S, phi, asub(H), asub(T), Ksub(Q), #sigma#sub(-1), #sigma#_1_0_0"4"5"0, #sigma#sub(0.2/100)) of VT3-1 (#alpha#+#beta#)-titanium alloy is studied. The dependences obtained allow one to determine globular structure parameters, providing necessary mechanical properties. In combination with data on the effect of thermal treatment conditions on structure parameters, results obtained in the paper may be used for structure control to increase a level of required characteristics.
Radiation modification on liquid retention properties of native cassava starch, gelatinized at 85"0C, by graft copolymerization with acrylonitrile was carried out by mutual irradiation to #gamma#-rays. A thin aluminium foil was used to cover the inner wall of the reaction vessel so that the extent of homo polymer could be reduced to be less than 1.6% with a distilled water retention value of 665 g/g of the dry weight of the saponified grafted product. Confirmations of graft copolymerization and saponification reactions were made by the infrared spectrophotometric technique. The combined effect of radiation parameters in terms of an irradiation time and a dose rate to the same total dose on the extent of grafting reaction expressed in terms of grafting parameters which directly influenced liquid retention values was evaluated in conjunction with statistical analysis.
Oils, tars, and degraded oils of varying degrees of biodegradation occur in the Permian Phosphoria Formation along the eastern flank of the Wind River mountains, Wyoming, US. Biodegradation has altered the isomer distributions of steranes, the hopanes, and the mono- and triaromatised steroids in these oils. The conventional maturity parameters based on these biomarkers are of limited use in estimating their maturity. On the other hand, even in severely biodegraded oils the vanadylporphyrin distributions are unaltered. Because of this, the Porphyrin Maturity Parameter (PMP) derived from the vanadylporphyrin distribution is an ideal parameter for estimating the maturity of these oils. This study also confirms the previous observation that T[sub s] and T[sub m] are unaffected by even severe biodegradation. 14 refs., 5 figs., 2 tabs.
The determination of the origin of seized nuclear material is important for authorities in the context of the criminal investigation, in order to return the material to its last legal owner and to help preventing any further diversion of material from this source. Origin determination is based on a complex pattern of parameters obtained through analytical measurements. The information required to determine the origin of nuclear materials may be divided into two categories: endogenous information (e.g. age or mode of production of the material) which is self-explanatory; whereas exogenous information (e.g. dimensions, surface roughness, impurities) requires a database to which the parameters can be compared. The Institute for Transuranium Elements has developed methods to determine characteristic parameters like impurities, surface roughness, or microstructural information. Furthermore, a database was set up containing ...
A one-dimensional thermal model is derived to describe the temperature field around a vertical borehole heat exchanger (BHEx) for a geothermal heat pump. The inlet and outlet pipe flows are modeled as one, and an effective heat capacity is added to model the heat storage in the fluid and pipes. Parameter estimation techniques are then used to estimate various parameters associated with the model, including the thermal conductivity of the soil and of the grout which fills the borehole and surrounds the u-tube. The model is validated using test data from an experimental rig containing sand with known thermal conductivity. The estimates of the sand thermal conductivity derived from the model are found to be in good agreement with independent measurements.
A one-dimensional thermal model is derived to describe the temperature field around a vertical borehole heat exchanger (BHEX) for a geothermal heat pump. The inlet and outlet pipe flows are modeled as one, and an effective heat capacity is added to model the heat storage in the fluid and pipes. Parameter estimation techniques are then used to estimate various parameters associated with the model, including the thermal conductivity of the soil and the grout that fills the borehole and surrounds the U-tube. The model is validated using test data from an experimental rig containing sand with known thermal conductivity. The estimates of the sand's thermal conductivity derived from the model are found to be in good agreement with independent measurements.
Experimental investigations have been conducted to determine two-phase natural circulation interfacial parameters by real-time neutron radiography. The natural circulation loop used in the present experiments consists of a vertical two-phase section, a gas liquid separator, and a gas injection/heating section. Experiments were performed in a neutron beam for visualization using realtime neutron radiography system. The natural circulation was initiated by injection of known gas flow rate in the heated section. Two-phase flow interfacial parameters including interfacial geometry and phase velocities etc. for bubbly flow and slug flow patterns observed in the experiments will be given in detail. The results indicate that while the natural circulation is largely as expected and that steady stable flows are possible, there are some local phenomena that introduce instabilities due to the interfacial phenomena between the liquid and the gas.
Experimental investigations have been conducted to determine two-phase natural circulation interfacial parameters by real-time neutron radiography. The natural circulation loop used in the present experiments consists of a vertical two-phase section, a gas liquid separator, and a gas injection/heating section. Experiments were performed in a neutron beam for visualization using realtime neutron radiography system. The natural circulation was initiated by injection of known gas flow rate in the heated section. Two-phase flow interfacial parameters including interfacial geometry and phase velocities etc. for bubbly flow and slug flow patterns observed in the experiments will be given in detail. The results indicate that while the natural circulation is largely as expected and that steady stable flows are possible, there are some local phenomena that introduce instabilities due to the interfacial phenomena between the liquid and the gas.
A previous analysis aimed at underlining the importance of the relativistic electron beam quality for the performances of a Free Electron Laser (FEL) is continued in the paper by the study of the influence of the undulator field (wiggler) parameters and of the optical beam (and/or optical cavity) quality on the operation of a FEL. The importance of parameters such as K, #lambda#_u, g of the undulator, F, P_L, #nu#_c of the optical beam, and L, L_o_p_t and L_c_r of the optical cavity for the characteristics of the input radiation as P_o_u_t, G_o_p_t, and #eta# are analyzed and some relations between these parameters that will give the possibility to estimate the corresponding values are given. Some proposal for the design of a compact FEL in IR-spectral region, with #lambda# #approx# 230 #mu#m are given. (Author).
In order to suppress resonance vibrations of a rotor-shaft of rotating machinery, a rotor-shaft system elastically supported by ball bearings which are installed in electromagnetic actuators are proposed and the design method of some compensatory circuits in the controller to control the electromagnetic actuators in the system are explained. These actuators are controlled by the analog PID (proportional, integral, and derivative) controller. The compensation for nonlinearity of electromagnetic force, the negative stiffness of electromagnet, and the time lag of the coil current are discussed and the effective control circuits are proposed. The rotor-shaft system is replaced by the equivalent two-degree-of-freedom system and both impulse and frequency responses are numerically simulated for several parameters of PD-controller gain. By applying the principle of dynamic absorbers, optimum parameters are calculated. The gains of the control circuit ...
Model selection aims to determine which theoretical models are most plausible given some data, without necessarily asking about the preferred values of the model parameters. A common model selection question is to ask when new data require introduction of an additional parameter, describing a newly-discovered physical effect. We review several model selection statistics, and then focus on use of the Bayesian evidence, which implements the usual Bayesian analysis framework at the level of models rather than parameters. We describe our CosmoNest code, which is the first computationally-efficient implementation of Bayesian model selection in a cosmological context. We apply it to recent WMAP satellite data, examining the need for a perturbation spectral index differing from the scale-invariant (Harrison-Zel'dovich) case.
This paper presents a new method for simultaneously selecting the power system stabilizer (PSS) parameters in multimachine power systems. Design of local output feedback power system stabilizer using local signal of the generator (e.g. speed or power) is formulated as a decentralized modal control (DMC) problem. Exact model reduction based on modal control theory is proposed to make the determination of PSS parameters highly efficient. Results obtained from the coordinated tuning of the parameters of three power system stabilizers equipped on a multimachine power system show that exact assignment of the eigenvalues associated with the poorly damped electromechanical modes can be achieved in a very efficient manner.
In order to understand the parameters of the standard model of electroweak and strong interactions (coupling constants, masses, mixing angles) one needs to embed the standard model into some larger theory that accounts for the observed values. This means some additional sector is needed that fixes and stabilizes the values of the fundamental constants of nature. In these lecture notes we describe in nontechnical terms how such a sector can be constructed. Our additional sector is based on rapidly fluctuating scalar fields that, although completely deterministic, evolve in the strongest possible chaotic way and exhibit complex behaviour. These chaotic fields generate potentials for moduli fields, which ultimately fix the fundamental parameters. The chaotic dynamics can be physically interpreted in terms of vacuum fluctuations. These vacuum fluctuations are different from those of QED or QCD but coupled with the same moduli fields as QED and QCD ...
The relationship between cigarette smoking and cell damage is complicated, particularly considering the role of oxidative stress. The aim of this study was to identify the relationships among plasma nicotine metabolites, lipophilic antioxidants, and metabolic parameters in smokers and non-smokers. This cross-sectional study recruited 100 subjects who visited the Department of Family Medicine at Kaohsiung Medical University Hospital. Excluding 14 ineligible cases, 46 smokers and 40 non-smokers were enrolled. Plasma nicotine metabolites, lipophilic antioxidants (including retinol, lycopene, a-carotene, b-carotene, d-tocopherol, g-tocopherol and a-tocopherol), related metabolic parameters, and body composition (including height, weight, body mass index, body fat, and waist circumference) were...
An experimental investigation has been carried out to examine for the first time the performance and combustion noise of an indirect injection diesel engine running with new fuel derived from pure jojoba oil, jojoba methyl ester, and its blends with gas oil. A Ricardo E6 compression swirl diesel engine was fully instrumented for the measurement of combustion pressure and its rise rate and other operating parameters. Test parameters included the percentage of jojoba methyl ester in the blend, engine speed, load, injection timing and engine compression ratio. Results showed that the new fuel derived from jojoba is generally comparable and a good replacement to gas oil in diesel engine at most engine operating conditions, in terms of performance parameters and combustion noise produced. (author)
The final report for a Laboratory Directed Research and Development project entitled, ``Capturing Recrystallization of Metals in a Multiscale Materials Model'' is presented. In this project, deformation and recrystallization processes have been followed experimentally and theoretically in order to incorporate essential mechanisms from the defect (dislocation) and grain size length scales. A nonlinear rotational gradient theory has been developed which enables the incorporation of microstructural parameters. The evolution of these parameters during deformation and recrystallization has been characterized qualitatively and quantitatively, applying various electron optic techniques ranging over several length scales. The theoretical and experimental framework developed is general. It has been exemplified by an application to recrystallization in single crystals and bicrystals of aluminum. The recrystallization process has been ...
Biodynamic parameters of the ragworm Nereis diversicolor from southern Spain and south England were experimentally derived to assess the inter-population variability of physiological parameters of the bioaccumulation of Ag, Cd and Zn from water and sediment. Although there were some limited variations, these were not consistent with the local metal bioavailability nor with temperature changes. Incorporating the biodynamic parameters into a defined biodynamic model, confirmed that sediment is the predominant source of Cd and Zn accumulated by the worms, accounting in each case for 99% of the overall accumulated metals, whereas the contribution of dissolved Ag to the total accumulated by the worm increased from about 27 to about 53% with increasing dissolved Ag concentration. Standardised va...
This paper discusses how specialized techniques for machine condition monitoring can help to eliminate false alarms and undetected faults, leading to a truly cost effective predictive maintenance program. It is vital to base the monitoring system on the parameter which will give the most useful information about potential faults and breakdowns. This parameter is generally agreed to be vibration. While oil debris analysis and variations in temperature, geometry and machine speed can all give advance warning of faults, no other parameter can reveal as wide a range of fault types as vibration. The vibration transducers job is to accurately and faithfully convert the vibration into an electric signal for assessment. If this part of the system is weak, reliability will be badly affected. Data integrity is crucial.
Oils in Jinghu sag are abundant with high content of polar compounds and have a low ratio of saturate to aro-matic hydrocarbons and a high ratio of resin to asphaltene. The gross composition of oils in the Jinghu sag suggests typical immature to low mature characteristics. Some compounds with low thermal stability were identified. Light hy-drocarbons, a carbon preference index, an odd even index, n-alkane and hopane maturity parameters show mature fea-tures and little differences in the maturity level among oils. Sterane isomerization parameters indicate an immature to low mature status of oil. Transfer of the sedimentary center during sedimentation has led to different thermal histories among subsags and thus generated oils with different maturities. On the basis of source analyses, four ...
Experimental data on A-15 binary phases (the lattice parameter dependence on composition, phase diagrams, etc.) have been considered and the so-called ''compounds with A-15 structure'' are shown to be solid solutions of element substitution in the structure of A-15 type. Values of lattice parameter and atomic volume of A-15 modifications for 21 elements have been obtained (for Zr, W, Nb, Mo, V in particular). There has been shown the possibility of calculation of atomic volumes and lattice parameters of A-15 binary phases at the lack of direct experimental data. The essential role of atomic volume relations of different phases has been observed for the estimation of stability conditions of A-15 phase.
Experimental data on A-15 binary phases (the lattice parameter dependence on composition, phase diagrams, etc.) have been considered and the so-called ''compounds with A-15 structure'' are shown to be solid solutions of element substitution in the structure of A-15 type. Values of lattice parameter and atomic volume of A-15 modifications for 21 elements have been obtained (for Zr, W, Nb, Mo, V in particular). There has been shown the possibility of calculation of atomic volumes and lattice parameters of A-15 binary phases at the lack of direct experimental data. The essential role of atomic volume relations of different phases has been observed for the estimation of stability conditions of A-15 phase.
This study is concerned to the perforation phenomena of the oblique dual-plate by projectile. Experiment and simulation related to that was carried out. the variables considered in this phenomena include the electrolytic zinc coated steel sheet and carbon steel rod. In the former, the confirmation and projectile velocity possible phenomena of real phenomena is done, the latter, the effect of parameter such as time-step and grid space length is analyzed by using the three-dimensional Lagrangian explicit time-integration finite element code, HEMP. This code use the eight node hexahedral elements and in this study, Von-Mises Criteria is used as the strength model, Mie-Gruneisen is as the Equation of State. The simulation was performed by contrast with the experiment. Through the calibration of the parameter of Lagrangian code, reasonable result was approached.
In this paper, the unsteady MHD free convection heat and mass transfer of viscous fluid flowing through a Darcian porous regime adjacent to a moving vertical semi-infinite plate under Soret and Dufour effect have been examined. Viscous dissipation effects are included in the energy equation. A uniform magnetic field is applied transversely to the direction of the flow. The differential equations governing the problem have been transformed by a similarity transformation into a system of non-dimensional differential equations which are solved numerically by element free Galerkin method. The influence of Grashof number (Gr), magnetic parameter (M), heat absorption parameter (Q), permeability parameter (K), Schmidt number (Sc), Soret number (Sr), and Dufour number (Du) on the velocity, tempera...
An appropriate mathematical model can help researchers to simulate, evaluate, and control a proton exchange membrane fuel cell (PEMFC) stack system. Because a PEMFC is a nonlinear and strongly coupled system, many assumptions and approximations are considered during modeling. Therefore, some differences are found between model results and the real performance of PEMFCs. To increase the precision of the models so that they can describe better the actual performance, optimization of PEMFC model parameters is essential. In this paper, an artificial bee swarm optimization algorithm, called ABSO, is proposed for optimizing the parameters of a steady-state PEMFC stack model suitable for electrical engineering applications. For studying the usefulness of the proposed algorithm, ABSO-based results...
In view of no satisfactory mathematical model is presently available for the dose-response curve of immunoradiometric assay, a three parameter model based on single binding site mass action law has been derived. A curve fitting method based on similar principle of linear robust regression was designed and a software was prepared for use on IBM personal computers. Experiments revealed that the model is applicable to a variety of IRMA systems as well as to time-resolved immunofluorometric assay of hAFP. When there was outlier(s) of the calibration curve, the average bias of unknown samples obtained with this method is significantly smaller than methods using four parameter logistic model or four parameter single site mass action model.
In this paper, a hybrid time-frequency method (HTM) based on the improved Morlet wavelet and auto terms window (ATW) is presented. The Morlet wavelet, for its shape is similar to the mechanical shock signals, is added two parameters which decide the shape of the mother wavelet. The added parameters and the appropriate scale parameter for continuous wavelet transformation (CWT) are calculated using the cross validation method (CVM) and the minimum Shannon entropy method. The useless noise in the original signal can be filtered by the CWT filter de-noising process. An ATW based on the Smoothed Pseudo Wigner-Ville Distribution (SPWVD) spectrum is designed as a window function to suppress the cross terms in Wigner-Ville Distribution (WVD). The gear fault diagnosis experiment results show that ...
System identification refers to estimation of process parameters and is a necessity in control theory. Physical systems usually have varying parameters. For such processes, accurate identification is particularly important. Online identification schemes are also needed for designing adaptive controllers. Real processes are usually of fractional order as opposed to the ideal integral order models. In this paper, we propose a simple and elegant scheme of estimating the parameters for such a fractional order process. A population of process models is generated and updated by particle swarm optimization (PSO) technique, the fitness function being the sum of squared deviations from the actual set of observations. Results show that the proposed scheme offers a high degree of accuracy even when the observations are corrupted to a significant degree. Additional schemes to improve the accuracy still further are also proposed and ...
A new stem taper function was established for individual trees of two poplar hybrid clones grown on a short-rotation coppice. The model could be easily fitted and required three parameters to be estimated. It can be used to estimate both diameter at a given height and height for a given top diameter. Two of the three parameters controlled the conical and the neiloid parts of the stem. Significant differences in these parameters were observed between the two clones even if no differences were observed for diameter at breast height or total height of the stem. The model could not be integrated to calculate volumes (total volume, merchantable volume), which were estimated by numerical integration. However, use of this new model allows the optimal length of billets to be determined and thus maximizes the merchantable biomass of poplar in short-rotation coppice by minimizing the biomass of residues.
Some of well known F{sub 2} layer anomalies might have their origin in lower atmosphere and some have extra terrestrial sources. It has been suggested that the phenomena occurring below the ionosphere such as thunderstorms, lightning/sprites, volcanic eruptions and earthquakes and above the phenomena like corona mass ejection, solar flares and extra terrestrial events may produce F{sub 2} layer signatures. In the present paper we have tried to summarize the effect of some phenomena occurring below the ionosphere like thunderstorms, lightning/sprites and seismic activity and the phenomena such as solar flares which occur above the ionosphere, on the ionospheric electron and ion temperatures. The paper also discusses possibilities. The ionospheric electron and ion temperatures were measured by the RrPAa payload aboard the Iindian SRrOSS-C2 satellite. The normal day's ion and electron temperatures have been compared to the temperatures recorded during the ...
The use of an extraction of the heme pigments hemoglobin and myoglobin as a test for the heat exposure of back bacon was investigated by treating back bacon at varying temperatures of 50-70 degrees...Full Text Available
Game theory models of animal contests make many non-mutually exclusive predictions, complicating empirical tests. These predictions regard the relationship between contest parameters and fighting ability,...Full Text Available
The scaling of reproductive parameters to body size is important for understanding ecological and evolutionary patterns. Here, we derived allometric relationships for the number and mass of seeds, eggs...Full Text Available
Digital information flow within the intensive care unit (ICU) continues to grow, with advances in technology and computational biology. Recent developments in the integration and archiving of these...Full Text Available
The automatic real-time system operating at the LU-10 linac and providing measurements of the parameters such as the beam current (average and pulse values), the electron energy, the linear density distribution of beam current, and also the conveyor speed is described in the paper.
New approaches to the risk assessment process are needed that might be more definitive and satisfying to the scientific community, interest groups, and the public at large. This commentary examines...Full Text Available
ObjectiveTo compare objective polysomnographic parameters between three cohorts: children with autism, with typical development, and with developmental delay without...Full Text Available
Water quality of the Citarum River and the Jatiluhur Reservoir in Indonesia was evaluated using C-14 radioisotope. A close relationship between the abiotic (physical and chemical) and the biotic (algal growth potential, primary productivity, chlorophylla and diversity index of planktonic and benthic macroinvertebrate) parameters was obtained. Algal growth potential to abiotic parameters relationship has the highest correlation coefficient and can be used as a pollution indicator. The other biotic parameters do not show clear relationship with the abiotic parameters. The Citarum water quality is the lowest in those locations which receive human and industrial waste from Bandung and its environment. This water cannot be used for drinking purposes and fishery. The water quality in other locations of the river, however, meets the criteria for agriculture. Agricultural waste does not show any drastic effect ...
... being reported (Kisseberth et al., 1984; Ma, 1989; Shore and Douben, 1994). Small mammals are useful indicator species because they have relatively small home ranges allowing a direct tie to the source of ...
We compare experimental data for temperature dependence of the magnetic order parameter and the magnetic excitations (spin waves) in materials with a quenched orbital moment and a well-defined spin quantum number. It is observed that the thermal decrease of the two quantities proceeds according to the same analytical function of the type y(T)=1-cT"#epsilon# with an identical exponent #epsilon#. This power function applies not only asymptotically for T->0 but holds over a wide temperature range. The exponent #epsilon# is universal, i.e. independent of spin order type and lattice symmetry and depends only on the dimensionality of the relevant interactions and on whether the spin quantum number is integer or half-integer. The different T"#epsilon# functions are identified as representations of stable universality classes. The fact that order parameter and magnetic excitations follow the same T"#epsilon# function shows that the two quantities ...
Operation of an X-ray spectrometer based on a spherical variable-line-spacing (VLS) grating is analyzed using dedicated ray-tracing software allowing fast optimization of the grating parameters and...Full Text Available
BackgroundThe aim of the present article was to evaluate whether angiogenic parameters as assessed by transvaginal color Doppler ultrasound (TVCD) may predict those prognostic factors...Full Text Available
The kinetic parameters of single bonds between neural cell adhesion molecules were determined from atomic force microscope measurements of the forced dissociation of the homophilic protein-protein bonds....Full Text Available
Method for description of X-ray radiation dose distribution based on semiempirical description of dose fields is suggested. At that dose field description parameters can be easily individualized for concrete X-ray device.
By use of a new computer-assisted u.v.-spectrophotometric assay method, the kinetic parameters of the reaction catalysed by Bacillus licheniformis 749/C beta-lactamase were re-examined and the mode...Full Text Available
The structural properties of brain extracellular space (ECS) are summarised by the tortuosity (λ) and the volume fraction (α). To determine if these two parameters were independent,...Full Text Available
... (restricted)] 256-264 Influence of likelihood function choice for estimating crop model parameters using the generalized likelihood uncertainty estimation method by He, Jianqiang & Jones, James W. & Graham, Wendy D. & Dukes, Michael D. [Downloadable! (restricted)]...
An approach to the calculation of the quantity of heat consumed in the process of coal formation is presented. The variability of this parameter in a coalification series is analyzed using coals from the Kuznetsk and Tunguska Basins as an example.
This talk sketches out the main parameters (technology, circuit design) that have an influence on the hardening of digital CMOS integrated circuits. For each technology the more common defects are mentioned. General design rules are proposed to prevent or limit those defects. (D.L.). 2 refs., 2 figs.
Despite their status as the most speciose group of terrestrial vertebrates, birds exhibit the smallest and least variable genome sizes among tetrapods. It has been suggested that this is because powered...Full Text Available
We present several new results on the classic problem of estimating Gaussian profile parameters from a set of noisy data, showing that an exact solution of the maximum likelihood equations exists...Full Text Available
ObjectivesThe aim of this study was to investigate the effect of cigarette smoking on clinical parameters and signs anemia of chronic disease in chronic periodontitis patients.Full Text Available
The criterion the study is based on in evaluating environmental risks is the possibility of harmful changes in air, water and soils rather than the harmful environmental impacts these changes are caused by. The two significant criteria, i.e. the evaluated environmental hazards potentials or 'value parameters', and the evaluated damage-to-the-environment probabilities or 'safety parameters', reveal the respective environmental risks or 'risk factors'. These risk factors are classified by 23 environmental risk parameters for differentiation between low-risk and high-aid for pollution abatement measures provided that one fixes acceptance limits for the environmental parameters. As a rule the environmental risks of technical facilities which handle hazardous materials can be evaluated appropriately and the results can be compared. (orig./HSCH).
This paper describes the technical design and performance of the diagnostic system installed in the tokamak TCABR to measure parameters of the plasma edge. The system consists of four Langmuir probes under remote control. (author)
PurposeTo determine the effects of age on global and sectoral peripapillary retinal nerve fiber layer (RNFL), macular thicknesses and optic nerve head (ONH) parameters...Full Text Available
BackgroundSupplementation of nutritional deficiencies helps to improve immune function and resistance to infections in malnourished subjects. However, the suggested benefits of dietary...Full Text Available
Examples are used to demonstrate that a shift in the point of emphasis is necessary with regard to radiation hazard in medicinal X-ray diagnosis. The parameters employed in this study to calculate somatic dose (SD) and somatically significant dose (SSD) m...
Heavy ion tests of a switching converter using power MOSFETs have allowed us to identify the main parameters which affect the burnout sensitivity of these components. The differences between static and dynamic conditions are clarified in this paper. (author). 7 refs., 16 figs., 3 tabs.
Carbon steel, copper, zinc and aluminium samples were exposed in different sizes with known ambient parameters in Gran Canaria Island and atmospheric corrosion was investigated. Weight-loss measurements used to determine corrosion damage were complemented...
The validation parameters for pharmaceutical analyses were examined for the accelerator mass spectrometry measurement of 14C/C ratio, independent of chemical separation procedures....Full Text Available
This work presents a digital adaptive Power System Stabilizer (PSS) which operates in a gain scheduling scheme. It`s parameters are designed for a lot of different operating regions in a P x Q plane (active and reactive powers), and saved in a microcomputer real time control. During working, the PSS identifies the present region of operation, and synthesizes its damping signal in accordance with the parameters for that region. As an extension of the method, a neural PSS, which uses the set of parameters of each region as a standard set to train a neural network to form this PSS, is also proposed. The tests presented show good performance for both PSS, when compared to a conventional (non adaptive) one. (author) 10 refs., 5 figs., 1 tab.; e-mail: jalb at guama.cpgee.ufpa.br
A method is presented to derive the absolute dimensions of early-type detached binaries by combining the observed parameters with results of evolutionary computations. The method is used to obtain the absolute dimensions of nine close binaries. We find that most systems have an initial masss ratio near 1.
BackgroundThe pH is an important parameter controlling many metabolic and signalling pathways in living cells. Recombinant fluorescent pH indicators (pHluorins) have come into vogue...Full Text Available