Energy Technology Data Exchange (ETDEWEB)

A two-dimensional mathematical model of a fault controlled geothermal reservoir has been developed. Heated water rising in a fault is assumed to charge a reservoir which is overlain by a thin impermeable, thermally conducting cap rock. The mass flow rate or the pressure associated with the charging process at the fault inlet is unknown and can only be estimated. Thus, the pressure in the fault at the bottom of the reservoir is assumed to be prescribed. Quasi-analytic solutions for the distributions of velocity, pressure, and temperature are obtained in the fault-reservoir system for high Rayleigh number flow. In this approximation, the upwelling fluid does not cool off appreciably until it reaches the cold upper boundary of the reservoir and encounters conductive heat loss. The thermal boundary layer, which is thin at the top of the fault, grows outward ...

Energy Technology Data Exchange (ETDEWEB)

A series of line fault tests have been conducted at completion of Stage I of the Hokkaido-Honshu HVDC Link of Electric Power Development Co., Ltd., prior to its commercial operation, in order to study transient overvoltages and overcurrents and to confirm safety operation of system protecting devices in case of DC transmission line faults. The Hokkaido-Honshu HVDC Link is a metallic return HVDC overhead line and cable transmission system, currently being a monopolar system. For this, measurements were conducted this time on reverse polarity overvoltages occurring on main line cable, return line overvoltages, fault arc dynamic characteristics, and DC bypass current through the AC system. The results obtained were then compared with the analysis results by the HVDC surge similator or digital simulation conducted for system design prior to the field tests. As a result, a close accordance was found between ...

Science.gov (United States)

Approximately 1.2 million kg of uranium oxide (yellow cake) has been produced from the area surrounding Gunnison, Colorado. Over 99 percent of this has come form the Cochetopa and Marshall Pass districts. Uranium in both districts and many of the other occurrences is associated closely with fault and shear zones which cut brittle host formations (sandstones and dolomites) of Paleozonic and Mesozoic age. Minor uranium occurrences are in pegmatites and shear zones in Precambrian rocks, Cambrian vein material, and sandstones of Tertiary age. In the paper presented, the uranium occurences are described by districts. In addition, possibilities for additional discoveries are discussed. (JMT)

Science.gov (United States)

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KoreaScience (Korea)

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International Nuclear Information System (INIS)

Certain postulated faults during refuelling of AGRs may give rise to compacted fuel and graphite sleeve debris. This debris must be maintained below some safe limiting temperature. As part of a programme to assess the benefits of natural convection in cooling such debris in a region experiencing no forced cooling, a simple geometry incorporating typical debris has been studied both experimentally and by prediction. The experiment comprised an array of electrically heated fuel rods mounted co-axially in a closed cylindrical vessel and surrounded by fragments of graphite. The vessel was cooled on its cylindrical surface, the ends being insulated. Rods and vessel wall were thermocoupled. Tests covered a range of temperature and pressures in both CO_2 and N_2. Significant natural convection heat removal was demonstrated, particularly at high pressure. Predictions utilising the PHOENICS code agreed well with measured temperatures over a wide range ...

Energy Technology Data Exchange (ETDEWEB)

The prediction of faults on high voltage transmission lines requires the detection of incipient faults, which is implemented by detection of the radio noise due to contaminated insulators, insulation deterioration, and improver connections. It is shown that the radio noise due to incipient faults is separable and identifiable from normal transmission line radio noise, hence faults can be predicted.

Science.gov (United States)

A new approach of gear fault diagnosis based on continuous wavelet transform is presented. Continuous wavelet transform can provide a finer scale resolution than orthogonal wavelet transform. It is more suitable for extracting mechanical fault information. In this paper, the concept of time-averaged wavelet spectrum (TAWS) based on Morlet continuous wavelet transform is proposed. Two fault diagnosis methods named spectrum comparison method (SCM) and feature energy method (FEM) based on TAWS are established. The results of the application to gearbox gear fault diagnosis show that TAWS can effectively extract gear fault information. The feature energy of the TAWS features the gear fault advancement very well and is conically proportional to the gear fault advancement.

Energy Technology Data Exchange (ETDEWEB)

Past movement on faults can be dated by measurement of the intensity of ESR signals in quartz. These signals are reset by local lattice deformation and local frictional heating on grain contacts at the time of fault movement. The ESR signals then grow back as a result of bombardment by ionizing radiation from surrounding rocks. The age is obtained from the ratio of the equivalent dose, needed to produce the observed signal, to the dose rate. Fine grains are more completely reset during faulting, and a plot of age vs. grain size shows a plateau for grains below critical size; these grains are presumed to have been completely zeroed by the last fault activity. We carried out ESR dating of fault rocks collected near the Gori nuclear reactor. Most of the ESR signals of fault rocks collected from the basement are saturated. This indicates that the last movement of ...

Science.gov (United States)

Attention is given to recent research on gear fault diagnostic techniques. A mathematic model for vibration signals of defective gears is presented. Novel methods of gear fault diagnosis, such as zoom complex envelope analysis, wideband demodulation techniques, bispectrum analysis, correlation spectrum analysis, and maximum entropy spectrum analysis, are demonstrated. The wide-band demodulation technique is found to exhibit a high SNR. Bispectrum and correlation spectrum are excellent for some mechanical fault forms.

Energy Technology Data Exchange (ETDEWEB)

Anomalous features in Gulf Coast Salt domes exhibit deviations from normally pure salt and vary widely in form from one dome to the next, ranging considerably in length and width. They have affected both conventional and solution mining in several ways. Gas outbursts, insolubles, and potash (especially carnallite) have led to the breakage of tubing in a number of caverns, and caused irregular shapes of many caverns through preferential leaching. Such anomalous features essentially have limited the lateral extent of conventional mining at several salt mines, and led to accidents and even the closing of several other mines. Such anomalous features, are often aligned in anomalous zones, and appear to be related to diapiric processes of salt dome development. Evidence indicates that anomalous zones are found between salt spines, where the differential salt intrusion accumulates other materials: Anhydrite bands which are relatively strong, and other, weaker impurities. ...

Energy Technology Data Exchange (ETDEWEB)

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 strong ground motion. ...

International Nuclear Information System (INIS)

Site studies for CANDU type NPP began in a careful manner since 1982 as a first part of the Nuclear Power Plant Romanian Program adopted by political and governmental authorities at the time. A team was charged to develop all packages of the necessary main studies. The first Romanian NPP CANDU 6 type reactor gone to erection on Cernavoda site, planned to have 5 units and, like Wolsong NPP, applied the same design for the nuclear island. For the BOP parts the ANSALDO-GE project was applied with a thorough concern about requirements raised by connection to NSP. The first mission of design and research multi-branch team was to adapt the NPP Cernavoda project having an open water cooling circuit 'once-through' to the new parameters of a close recirculation water cooling circuit. Also, the structural design was re-evaluated for the case of soft foundation strata instead of hard rock ones. The close recirculation water cooling circuit system was ...

Energy Technology Data Exchange (ETDEWEB)

Considers fundamental problems involved in the precise location of faults on high-voltage transmission lines. The influence of pre-fault load on the distance-to-fault measurement problem is analysed and a new method of accounting for load effects is presented. Two of the algorithms considered are precise, containing no simplifyng assumptions and their overall accuracy is limited only by the accuracy of digital impedance relays at both ends of the protected circuit. A third algorithm presents a new approach to the fault location problem, which requires digital impedance relays at one end only of a transmission line. The procedures described are applicable to any system arrangement and are suitable for a wide range of fault resistance values.

Energy Technology Data Exchange (ETDEWEB)

The analysis of transmission line faults is essential to the proper performance of the power system. It is required if protective relays are to take the appropriate action and in monitoring the performance of relays, circuit breakers, and other protective and control elements. The detection and classification of transmission line faults is a fundamental component of such fault analysis. Another application of fault analysis is in software packages for automated analysis of digital fault recorder (DFR) files. Recently, such a package, called DFR Assistant, was developed for substation applications. This program can be installed locally in a substation, in which case it is connected directly to the DFR via a high speed parallel link, or it can be installed at a central station, in which case it can be configured to automatically analyze events coming from all DFRs.

Energy Technology Data Exchange (ETDEWEB)

Faults in shallow, unconsolidated sediments, particularly in coastal plain settings, are very difficult to discern during subsurface exploration yet have critical impact to groundwater flow, contaminant transport and geotechnical evaluations. This paper presents a case study using cross-over geophysical technologies in an area where shallow faulting is probable and known contamination exists. A comparison is made between Wenner and dipole-dipole resistivity data, ground penetrating radar, and high resolution seismic data. Data from these methods were verified with a cone penetrometer investigation for subsurface lithology and compared to existing monitoring well data. Interpretations from these techniques are compared with actual and theoretical shallow faulting found in the literature. The results of this study suggests that (1) the CPT study, combined with the monitoring well data may suggest that discontinuities in ...

Science.gov (United States)

The fault signature can be revealed by vibration analysis in machine fault detection and diagnosis. Empirical mode decomposition (EMD) is a self-adaptive method that can decompose a vibration signal into informative intrinsic mode functions (IMFs). This paper addresses the improvement of the weakness of the traditional EMD algorithm and presents a new midpoint-based EMD method for effective fault signature analysis of a rotating machine. In the proposed method, geometrical midpoints of successive extrema are employed to estimate the local mean of an analyzed signal. Signal decomposition is then self-adaptively performed to achieve IMFs through removal of the midpoint-based local means. The representative IMF containing fault information is selected for identifying the fault signature. The effectiveness of the proposed method was verified by means of simulation and an application to ...

Energy Technology Data Exchange (ETDEWEB)

The fault detection and diagnosis system for gas engines was developed to improve the reliability of cogeneration systems (CGS). Most of existing fault detection systems monitor the trend of each part condition of engines and diagnose faults based on trend change, resulting in slow detection. Although early detection systems are available, those are complex, expensive and poor in flexibility and applicability. Since CGSs combined with gas engines increased to 1/3 of the whole CGS, engine troubles cause possible serious faults. The fault diagnosis system was thus developed to prevent serious faults which can early detect, in particular, abnormal conditions of parts around a combustion chamber such as ignition plug, intake valve and exhaust valve by monitoring exhaust pressure waveforms in an exhaust collector. Since this system can detect progressive occurrence ...

Energy Technology Data Exchange (ETDEWEB)

A triangle zone, which commonly occurs along the external margin of a foreland thrust and fold belt with a buried thrust front, is underlain by a subhorizontal, blind, foreland-verging thrust that ends against a foreland-dipping, hinterland-verging thrust. These contemporaneous thrusts, active towards the end of orogenesis, enclose an intercutaneous wedge that moved towards the foreland. During orogenesis, a triangle zone evolves through periodic replacement of faults bounding the active wedge. Replacements occur in cycles during each of which a lower fault tends to be replaced by one in a lower stratigraphic horizon, an upper fault by one farther away from the foreland. Each cycle ends with the lower fault moving to a younger horizon where it joins a new, more external upper fault. Near Coalspur, the triangle zone exposes the remnants of several wedges involving Upper Cretaceous ...

Science.gov (United States)

Seeking effective methods is one of the most important goals in machinery fault diagnosis. The effective methods for gear fault diagnosis have been successively developed in our Institute. This paper is a comprehensive treatise based on our research work of recent years. A mathematical model of vibration signals for defective gears is physically described. Five effective new methods for gear fault diagnosis, such as zoom complex envelope analysis, wideband demodulation technique, bispectrum analysis, correlative spectrum analysis, and maximum entropy spectrum analysis for phase modulated signals, are summarily presented. The listed illustrations prove sufficiently the validation of these methods.

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

Malfunctions in machinery are often sources of reduced productivity and increased maintenance costs in various industrial applications. For this reason, machine condition monitoring is being pursued to recognise incipient faults. In this paper, the fault diagnostic problem is tackled within a neuro-fuzzy approach to pattern classification. Besides the primary purpose of a high rate of correct classification, the proposed neuro-fuzzy approach also aims at obtaining an easily interpretable classification model. The efficiency of the approach is verified with respect to a literature problem and then applied to a case of motor bearing fault classification.

Energy Technology Data Exchange (ETDEWEB)

An approach for classification of transmission line faults is presented. The approach is based on fuzzy logic and requires the consideration of the samples of three phase currents at one end of transmission line. To illustrate the effectiveness of the proposed approach extensive simulation studies, using EMTP and MATLAB, have been carried out for different types of fault considering wide variations in the operating conditions. (author)

Energy Technology Data Exchange (ETDEWEB)

Resonant overvoltages in EHV transformers can be initiated by transmission line faults. A series of field tests were performed on the 151 mile long Kammer-Marysville 765 kV line in which a sequence of single line to ground faults were applied to one outside phase at 4 different locations. Fault location criteria and fault initiation procedures are presented. Oscillograms recorded the 3 phase response at both terminals of the line; one is transformer terminated, the other is open-ended. A frequency spectrum analysis of the waveforms is provided showing transient frequencies of sufficient magnitude and duration near the EHV transformer's resonant frequency to stimulate internal winding resonant overvoltages. Digital computer studies are presented and agree with the field tests quite favorably.

British Library Electronic Table of Contents (United Kingdom)

In the present scenario of market driven business, power supply has become more like a commodity. Reliable and quality power need to be ensured to meet customer requirements. In such a situation, it is extremely important that transmission line faults be identified accurately, reliably and in quick time. Advanced signal processing tools such as discrete wavelet transform (DWT) can be used very effectively for parameterisation and characterization of the fault signals. On the other hand, properly configured neural network (NN) can be utilized for classification of the faults based on the DWT signal. The present contribution uses electromagnetic transient program (EMTP) for modeling of a real transmission system and MATLAB for DWT and NN. Various types of faults have been simulated at differ...

Energy Technology Data Exchange (ETDEWEB)

Transmission line faults must be located accurately to allow maintenance crews to arrive at the scene and repair the faulted section as soon as possible. Rugged terrain and geographical layout cause some sections of power transmission lines to be difficult to reach. In the past, a variety of fault location algorithms were introduced as either an add-on feature in protective relays or stand-alone implementation in fault locators. In both cases, the measurements of current and voltages were taken at one terminal of a transmission line only. Under such conditions, it may become difficult to determine the fault location accurately, since data from other transmission line ends are required for more precise computations. In the absence of data from the other end, existing algorithms have accuracy problems under several circumstances, such as varying switching and loading conditions, ...

Energy Technology Data Exchange (ETDEWEB)

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 ...

Science.gov (United States)

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), ...

Science.gov (United States)

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 ...

Energy Technology Data Exchange (ETDEWEB)

Seismic transects in this area show a strongly reflective Moho of generally low relief, which, in the area of modern transects, consists of a thin zone (< 2 km thick) of short reflectors. The upper mantle is transparent and has a P{sub n} of 7.8-8.0 km/s similar to much of the western US. A lower crustal zone, 2-13 km thick, has variable internal reflectivity and a relatively low velocity of 6.6-6.8 km/s. Upper mantle peridotite xenoliths show both ductile and brittle deformational features and have structures and composition affected by magmatic intrusion; intrusions form complex dike systems and extensive zones of grain boundary infiltration in peridotite xenoliths. Whereas melt infiltration preceded and followed ductile deformation, brittle deformation, represented by closely spaced joint systems and faults, followed ductile deformation and is related to the youngest magmatic episodes. Lower crustal xenoliths are dominantly ...

Energy Technology Data Exchange (ETDEWEB)

An outline of the multi-fault diagnostic observation concept is presented in the paper. Starting from the commonly used singular value decomposition (SVD) it is shown, that it is equivalent to the modern version of principal component analysis (PCA). During the development of the concept of multi-fault observation several indices and measures obtained from SVD were tried, and some seem to bring the success. This problem is also addressed in the paper and illustrated by real examples taken from railroad Diesel engine condition monitoring. (orig.)

Energy Technology Data Exchange (ETDEWEB)

The Systems Analysis Programs for Hands-on Integrated Reliability Evaluations (SAPHIRE) refers to a set of several microcomputer programs that were developed to create and analyze probabilistic risk assessments (PRAs), primarily for nuclear power plants. The Fault Tree, Event Tree, and Piping and Instrumentation Diagram (FEP) editors allow the user to graphically build and edit fault trees, and event trees, and piping and instrumentation diagrams (P and IDs). The software is designed to enable the independent use of the graphical-based editors found in the Integrated Reliability and Risk Assessment System (IRRAS). FEP is comprised of three separate editors (Fault Tree, Event Tree, and Piping and Instrumentation Diagram) and a utility module. This reference manual provides a screen-by-screen guide of the entire FEP System.

Science.gov (United States)

A novel approach to fault diagnosis is proposed using multiscale morphology analysis to extract impulsive features from the signals with strong background noise. Multiscale morphology is applied to one-dimensional signal by defining both the length and height scales of structuring elements (SEs). A local-peak-value based adaptive algorithm is also introduced. The new approach makes the selection of SEs more transparent and is independent of empirical rules. Both simulated impulsive and vibration signals of two defective roller bearings are employed to validate the proposed algorithm. The roller bearing faults presented in the validation include both inner and outer race faults. The test results show that the multiscale morphology analysis is effective and robust to extract morphological features.

British Library Electronic Table of Contents (United Kingdom)

Fault symptoms of running gearboxes must be detected as early as possible to avoid serious accidents. Diverse advanced methods are developed for this challenging task. However, for multiwavelet transforms, the fixed basis functions independent of the input dynamic response signals will possibly reduce the accuracy of fault diagnosis. Meanwhile, for multiwavelet denoising technique, the universal threshold denoising tends to overkill important but weak features in gear fault diagnosis. To overcome the shortcoming, a novel method incorporating customized (i.e., signal-based) multiwavelet lifting schemes with sliding window denoising is proposed in this paper. On the basis of Hermite spline interpolation, various vector prediction and update operators with the desirable properties of biorthog...

British Library Electronic Table of Contents (United Kingdom)

A marine propulsion system is a very complicated system composed of many mechanical components. As a result, the vibration signal of a gearbox in the system is strongly coupled with the vibration signatures of other components including a diesel engine and main shaft. It is therefore imperative to assess the coupling effect on diagnostic reliability in the process of gear fault diagnosis. For this reason, a fault detection and diagnosis method based on bispectrum analysis and artificial neural networks (ANNs) was proposed for the gearbox with consideration given to the impact of the other components in marine propulsion systems. To monitor the gear conditions, the bispectrum analysis was first employed to detect gear faults. The amplitude-frequency plots containing gear characteristic sign...

UK PubMed Central (United Kingdom)

¹⁴C-dated Holocene coastal uplift, conventional and satellite geodetic measurements, and coseismic and aseismic fault slip reveal the pattern of distributed deformation at Taiwan resulting...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

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.

British Library Electronic Table of Contents (United Kingdom)

Varying load can cause changes in a measured gearbox vibration signal. However, conventional techniques for fault diagnosis are based on the assumption that changes in vibration signal are only caused by deterioration of the gearbox. There is a need to develop a technique to provide accurate state indicator of gearbox under fluctuating load conditions. This paper presents an approach to gear fault diagnosis based on complex Morlet continuous wavelet transform under this condition. Gear motion residual signal, which represents the departure of time synchronously averaged signal from the average tooth-meshing vibration, is analyzed as source data due to its lower sensitiveness to the alternating load condition. A fault growth parameter based on the amplitude of wavelet transform is proposed ...

UK PubMed Central (United Kingdom)

Purpose. To evaluate the efficacy of percutaneous transluminal angioplasty (PTA) in the management of arterial stenosis located close to the allograft anastomosis (close-TRAS)....Full Text Available

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Energy Technology Data Exchange (ETDEWEB)

The spatial connection between the zones of deep-lying faults and the narrowly-localized paleo-relief sections posessing an anomolous sedimentation condition in the latter Cretaceous is identified. It is established that this is of significance in choosing the primary regions for conducting oil exploration.

Science.gov (United States)

In this work, energy-based features for gear fault diagnosis and prediction are proposed. The instantaneous energy density is shown to obtain high values when defected teeth are engaged. Three methods are compared in terms of sensitivity, reliability and computation effectiveness. The Wigner Ville distribution is contrasted to the wavelet transform and the newly proposed empirical mode decomposition scheme. It is shown that all three methods are capable of a reliable prediction. An empirical law, which relates the energy content to the crack magnitude is established.

Energy Technology Data Exchange (ETDEWEB)

This project is a follow-up of the first development of a 500 kV HVDC airblast circuit breaker (EPRI project 1507-3). The objective was to increase the current interrupting capability from 2200 A to 4000 A and shorten its fault clearing time. A high current 500 kV HVDC circuit breaker has been built using the passive commutation circuit. The breaker is modular in construction and can be designed for a wide variety of system conditions. More than 400 current interruptions were carried out successfully. Tests have shown that this circuit breaker is capable of interrupting more than 4000 A dc. Practical breakers with current interrupting capability of even 5500 A dc could be built. The circuit breaker operation and the fault-clearing process can be materially speeded up if the trip signal is given as soon as the fault is detected and without waiting for the current levels to come down in response to converter control action. ...

Energy Technology Data Exchange (ETDEWEB)

The results of these investigations can be summarised as follows: At simulated operating stress most naturally occuring faults in welded- and cast iron parts develop cracks and can be assessed for reliability under fatigue-,creep- and creep fatigue behaviour according to the laws of fracture mechanics. The empirically determined correlation between the real fault size and the ultrasonic inspection results (height of echo, echo dynamics, sound weakening) lead to better assessment of real fault extension in turbine components. It is very important to adapt the method of inspection and assessment to the type of possible fault.(orig.) [German] Die bei diesen Untersuchungen ermittelten Ergebnisse lassen sich wie folgt zusammenfassen: - Die Mehrzahl der untersuchten natuerlichen Fehlstellen in den Schmiede- und Gussstuecken verhalten sich unter den simulierten Betriebsbeanspruchungen rissartig und sind damit ...

Energy Technology Data Exchange (ETDEWEB)

Distance protection, differential protection and directional comparison schemes are presently used for protecting transmission lines. Directional comparison relays are set to respond to faults in the protection zone without intentional time delay and are, therefore, used where high-speed fault clearing is needed. Artificial Neural Networks (ANNs) can handle most situations which cannot be defined sufficiently for finding a deterministic solution. The design and testing of an ANN for directional comparison protection of transmission lines are presented in this paper. Training patterns were generated using voltage and current samples for faults at various locations along a transmission line. The faults were simulated using an electromagnetic transient program and a sample three-phase power system. The performance of the proposed discriminator was checked using data simulated for testing and the ...

British Library Electronic Table of Contents (United Kingdom)

The generalized demodulation time-frequency analysis is a novel signal processing method, which is particularly suitable for the processing of multi-component amplitude-modulated and frequency-modulated (AM-FM) signals as it can decompose a multi-component signal into a set of single-component signals whose instantaneous frequencies own physical meaning. While fault occurs in gear, the vibration signals measured from gearbox would exactly display AM-FM characteristics. Therefore, targeting the modulation feature of gear vibration signal in run-ups and run-downs, a fault diagnosis method in which generalized demodulation time-frequency analysis and envelope order spectrum technique are combined is put forward and applied to the transient analysis of gear vibration signal. Firstly the multi-...

British Library Electronic Table of Contents (United Kingdom)

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...

British Library Electronic Table of Contents (United Kingdom)

Roller bearing is one of the most widely used elements in rotary machines. Condition monitoring of such elements is conceived as pattern recognition problem. Pattern recognition has three main phases: feature extraction, feature selection and feature classification. Histogram features can be used for fault diagnosis of roller bearing. This paper presents the use of decision tree for selecting best few histogram features (bin ranges) that will discriminate the fault conditions of the bearing from given train samples. These features are extracted from vibration signals. A rule set is formed from the extracted features and fed to a fuzzy classifier. The rule set necessary for building the fuzzy classifier is obtained largely by intuition and domain knowledge. This paper also presents the usag...

Energy Technology Data Exchange (ETDEWEB)

Breaker failure relaying has been generally achieved through the use of a current monitoring relay to determine whether current continues to flow into a fault after a breaker has been instructed to interrupt the circuit. If current continues to flow after a predefined period of time, the circuit breaker is considered to have failed. Steps must then be taken to trip the next set of upstream breakers in the power system to remove the faulted circuit and prevent system damage. However, with industrial power systems, this may be the utility`s breakers on the feeding transmission line. Regardless, breaker failure schemes must be designed to isolate both the faulted circuit and the failed circuit breaker. This paper discusses a new and innovative method of protecting a circuit breaker from the failure described above, plus other failures that go unprotected with conventional schemes, this providing total breaker failure ...

Energy Technology Data Exchange (ETDEWEB)

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 ...

Science.gov (United States)

This paper presents a novel feature extraction scheme for roller bearing fault diagnosis utilizing generalized S transform and two-dimensional non-negative matrix factorization (2DNMF). The generalized S transform, which can make up the poor energy concentration of the standard S transform, is introduced to generate the time-frequency representation (TFR). Experiment results on simulated signal and vibration signals measured from rolling element bearings have revealed that the generalized S transform can obtain a more satisfactory TFR than other similar techniques. Furthermore, a new technique called two-dimensional non-negative matrix factorization (2DNMF), which can reduce the computation cost and preserve more structure information hiding in original 2D matrices compared to the NMF, is developed to extract more informative features from the time-frequency matrixes for accurate fault classification. Experimental results on bearing ...

Energy Technology Data Exchange (ETDEWEB)

The subject of FDD (fault detection and diagnosis) has gained widespread industrial interest in machine condition monitoring applications. This is mainly due to the potential advantage to be achieved from reduced maintenance costs, improved productivity and increased machine availability. This paper presents a new FDD scheme for condition machinery of an industrial steam turbine using a data fusion methodology. Fusion of a SVM (support vector machine) classifier with an ANFIS (adaptive neuro-fuzzy inference system) classifier, integrated into a common framework, is utilized to enhance the fault detection and diagnostic tasks. For this purpose, a multi-attribute data is fused into aggregated values of a single attribute by OWA (ordered weighted averaging) operators. The simulation studies indicate that the resulting fusion-based scheme outperforms the individual SVM and ANFIS systems to detect and diagnose incipient steam turbine ...

Energy Technology Data Exchange (ETDEWEB)

The Feedwater System supplies feedwater to the steam generator at the required pressure, temperature and flow rate during the plant start-up, normal power operation, shutdown. When the Feedwater System is inoperable or unavailable, the Auxiliary Feedwater System supplies emergency feedwater to the steam generator. If main steam line break occurs, the increase of feedwater flow rate of the faulted steam generator due to decrease of the pressure in the faulted steam generator results in adverse effects in aspect of overcooling the Reactor Coolant System and increased containment pressure/temperature. To optimize the containment mass/energy analysis, this paper evaluates the maximum feedwater and auxiliary feedwater flow rate delivered to the faulted steam generator at each stage of pressure decrease in the faulted steam generator after a main steam line break accident. Calculated Feedwater flows are ...

Energy Technology Data Exchange (ETDEWEB)

The purpose of this paper is to present an analysis of lightning fault detection, location and protection using numeric distance relays applied in high voltage transmission lines, more specifically in the 500 kV transmission lines of CEMIG (Brazilian Energy Utility) between the Vespasiano 2 - Neves 1 (short line - 23.9 km) and Vespasiano 2 - Mesquita (long line - 148.6 km) substations. The analysis was based on the simulations results of numeric distance protective relays on power transmission lines, realized in September 02 to 06, 2002, at Siemens AG's facilities (Erlangen - Germany), using Real Time Digital Simulator (RTDS{sup TM}). Several lightning faults simulations were accomplished, in several conditions of the electrical power system where the protective relays would be installed. The results are presented not only with the times of lightning faults elimination, but also all the functionality of a ...

Energy Technology Data Exchange (ETDEWEB)

A method, which estimates the lightning performance of high voltage transmission lines based on the Monte-Carlo simulation technique, is described in this paper. The average number of faults which occur in a transmission line, dividing them in single-phase and three-phase faults, as well as the average grounding resistances of the transmission lines are calculated. The method is applied, on several operating Greek transmission lines, showing good correlation between predicted and field observation results. The proposed method can be used as a useful tool in the design of electric power systems, aiding in the right insulation dimensioning of a transmission line.(author)

Energy Technology Data Exchange (ETDEWEB)

This paper reports the development of a relay coordination package specially designed as a teaching aid. Fault studies required for relay coordination has been performed by using a newly developed loop impedance matrix. This new method of forming loop impedance matrix is particularly suitable for multiple fault studies environment as required in relay coordination. A simple topology searching technique has been used to find all loops of the network. This package simultaneously serves the purpose of teaching relay coordination, loop analysis technique and the method of topology searching.

Energy Technology Data Exchange (ETDEWEB)

The authors have interpreted 1,400 km of industry and government multichannel seismic reflection data from eastern Lake Superior. Seismic sequences have been identified by using reflection character and reflector terminations and truncations. This framework, coupled with outcrop information, has allowed them to assign lithologic units to some of these reflectors and reconstruct the timing and geometry of structures within the basin. The authors have mapped the Base Jacobsville-Bayfield Group/Top oronto Group, Base oronto Group/Top Keweenawan volcanics, and Basement as well as several reflectors internal to these groups. Integration of gravity and magnetic data with the seismic grid permits regional mapping of faults and folds between seismic lines. In the eastern part of the basin, high-angle basement-involved reverse faults, such as the southeastern combination of the Keweenaw fault, trend NNW-SSE, while broad folds trend ...

International Nuclear Information System (INIS)

Three model boilers, manufactured to simulate full-size tube sheet crevices, were tested with various secondary side environments. The first was faulted with organics representative of the decomposition of humic acid. The second was faulted with sodium carbonate and sodium hydroxide, while the third was faulted with sodium sulfate and sodium hydroxide. Each model contained seven tubes, which included Alloy 600 in the mill-annealed (MA) and thermally-treated (TT) conditions and Alloy 690 in the thermally-treated condition. Two models contained Alloy 800 tubes in the mill-annealed condition and one had Alloy 800 in the mill-annealed/cold-worked/glass-bead-peened condition. Two different sizes of tubesheet crevices were used in all model boilers. In the organics-faulted boiler, tubes of Alloy 600MA, Alloy 690TT and Alloy 800MA experienced no significant intergranular attack (IGA); however, the Alloy 600TT ...

Wastenet

...smart grid applications where you could place them very close to the high-voltage transmission lines , very close to transformers and so on. Photo:...

KoreaScience (Korea)

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KoreaScience (Korea)

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KoreaScience (Korea)

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DEFF Research Database (Denmark)

Udgivelsesdato: 2009

Energy Technology Data Exchange (ETDEWEB)

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 though some far ...

International Nuclear Information System (INIS)

In connection with some applications of asymptotic numbers and asymptotic functions, proposed by Khr.Khristov, the problem of describing subsets of asymptotic numbers closed with respect to algebraic operations arises. The algebraic operations with asymptotic numbers are defined by classes of their representatives. All trivial or noncharacteristic solutions are avoided. A procedure for constructing sets of elements closed under action of an algebraic operation or a combination of two or more of them is given. It turns out that the closed sets are given by their kernels, the last being the minimal subsets which generate the whole set by the introduced algebraic operations. It is proved that such kernels exist always. . The closed sets are described by their correspondence with the kernels. (S.P.).

CERN Document Server

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 ...

Energy Technology Data Exchange (ETDEWEB)

In the Hokuriku area along the coast of the Japan Sea, thunderstorms often occurred not only in summer but also in winter, and this resulted in the shutdown of electricity supply or damage of equipment. This study was concerning the observation of the lightning channels in the Hokuriku area through a year by many still cameras equipped with liquid-crystal shutters. The following conclusions were obtained: Among 165 lightning incidents photographed during 2 years, there included 172 incidents of the falling thunderstorms and 23 incidents of simultaneously falling thunderstorms at multi-area. In the case of winter, frequency to occur simultaneously falling thunderstorms at multi-area was higher and the upward falling thunderstorms were more. There was a tendency that the duration time of the lightning current in winter was longer than in summer. In winter, frequency to occur the upward falling thunderstorms was higher, about 61% of the upward falling thunderstorms rose from the ...

Energy Technology Data Exchange (ETDEWEB)

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 report we discuss ...

Science.gov (United States)

High precision, fast computation speed, as well as a good capability of fault tolerant and reconstruction are required more and more for spacecraft attitude determination system. To realize the above requirement, an approach was presented to the synthesis of federated filters using sigma point technique. In this algorithm, the sigma point technique brought the algorithm a high precision, while the federated structure significantly enhanced the filters' capability of multi-rate information fusion, fault tolerance, and system modularity. Within consideration of computation consumption, a simple information-sharing formulation was derived to adapt to the special property of sigma point distribution, and a dynamical information sharing strategy for multi-rate fusion was developed. A numerical simulation example was employed to give the algorithm a test, where the simulated system contained a suit of gyroscopes; a three-axis magnetometer and a sun ...

Energy Technology Data Exchange (ETDEWEB)

Samples of pure Cu, bronze (Cu-10 wt.% Zn) and brass (Cu-30 wt.% Zn) with stacking fault energies (SFE) of 78, 35, and 14 mJ/m{sup 2}, respectively, were processed by high-pressure torsion (HPT) and by a combination of HPT followed by cold-rolling (CR). X-ray diffraction measurements indicate that a decrease in SFE leads both to a decrease in crystallite size and to increases in microstrain, dislocation and twin densities for the HPT and HPT + CR processed ultrafine-grained (UFG) samples. Compared with processing by HPT, subsequent processing by CR refines the crystallite size of all samples, increases the twin densities of UFG bronze and brass, and increases the dislocation density in UFG bronze. It also decreases the dislocation density in UFG brass and leads to an unchanged dislocation density in UFG copper. The results suggest there may be an optimum stacking fault energy for dislocation accumulation in UFG Cu-Zn alloys and this has ...

Energy Technology Data Exchange (ETDEWEB)

A newly developed discrete-time adaptive sliding mode power system stabilizer (PSS) is proposed in this paper. Because the proposed PSS is developed in the pure discrete-time domain it is able to maintain the stability with the rather slower smapling frequency compared to discretized conventional continuous-time sliding mode PSS. The proposed PSS has the three main superiorities to the conventional PSS. First, because the proposed PSS utilizes the sliding mode control method, it has the strong robustness to the variations of the system parameters. Hence, it can overcome the minor disturbances such as identification errors, modeling errors, etc. Second, the proposed PSS needs only input/output measurements as feedback signals. Hence, it does not need the measurements of the state variables as the conventional sliding mode PSS or PSS based on the linear quadratic control method does. Finally, because the proposed PSS have the adaptive property, it is able to overcome the various power ...

International Nuclear Information System (INIS)

Determining the time of most recent fault movement is an important part of assessing a possible site for a nuclear power plant. The purpose of this paper is not to present research information but to provide a practical guide to some of the dating techniques available to the engineering geologist working on nuclear power plant siting. Emphasis is placed on the practical aspects, such as usable minerals, conditions necessary for them to yield correct dates, degree of accuracy, sample collection, sample size, and sample packaging. In this paper, the usual geologic field techniques are taken for granted (such as those used in stratigraphy, paleontology, and structural analysis) for assessing fault history. Laboratory techniques used in conjunction with or supplemental to field methods are discussed. The specific radiometric methods discussed are "1"4C(carbon-14), fission track, K-Ar (potassium-argon), thermoluminescense, Rb-Sr ...

Energy Technology Data Exchange (ETDEWEB)

Leakage of CO{sub 2} and displaced brine from geologic carbon sequestration (GCS) sites into potable groundwater or to the near-surface environment is a primary concern for safety and effectiveness of GCS. The focus of this study is on the estimation of the probability of CO{sub 2} leakage along conduits such as faults and fractures. This probability is controlled by (1) the probability that the CO{sub 2} plume encounters a conductive fault that could serve as a conduit for CO{sub 2} to leak through the sealing formation, and (2) the probability that the conductive fault(s) intersected by the CO{sub 2} plume are connected to other conductive faults in such a way that a connected flow path is formed to allow CO{sub 2} to leak to environmental resources that may be impacted by leakage. This work is designed to fit into the certification framework for geological CO{sub 2} storage, which represents ...

British Library Electronic Table of Contents (United Kingdom)

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 ...

British Library Electronic Table of Contents (United Kingdom)

Timely detection of the pneumatic system problems is important in industry. Many techniques have been employed to solve this problem. In this paper, Genetic Algorithm (GA) based optimal configuration of neural networks is proposed for fault diagnostic of bottle filling systems. Back-propagation is used for neural networks algorithm. The back-propagation algorithm had six inputs and one output. A fitness function was designed to the minimize execution time of ANN model by keeping the number of hidden layer(s) and nodes as low as possible while the mean square error of estimated output error is minimized. The designed GA-ANN combination and the graphical user interface (GUI) eliminate the trial and error process for selection of the fastest and most accurate configuration. The performance of...

British Library Electronic Table of Contents (United Kingdom)

The ensemble empirical mode decomposition (EEMD) can overcome the mode mixing problem of the empirical mode decomposition (EMD) and therefore provide more precise decomposition results. Wavelet neural network (WNN) possesses the advantages of both wavelet transform and artificial neural networks. This paper combines the merits of EEMD and WNN to propose an automated and effective fault diagnosis method of locomotive roller bearings. First, the vibration signals captured from the locomotive roller bearings are preprocessed by EEMD method and intrinsic mode functions (IMFs) are produced. Second, a kurtosis based method is presented and used to select the sensitive IMF. Third, time- and frequency-domain features are extracted from the sensitive IMF, its frequency spectrum and its envelope spe...

British Library Electronic Table of Contents (United Kingdom)

Abstract: The basement of the South China Sea (SCS) and adjacent areas can be divided into six divisions (regions) - Paleozoic Erathem graben-faulted basement division in Beibu Gulf, Paleozoic Erathem strike-slip pull-apart in Yinggehai waters, Paleozoic Erathem faulted-depression in eastern Hainan, Paleozoic Erathem rifted in northern Xisha (Paracel), Paleozoic Erathem strike-slip extending in southern Xisha, and Paleozoic-Mesozoic Erathem extending in Nansha Islands (Spratly) waters. The Pre-Cenozoic basement in the SCS and Yunkai continental area are coeval within the Tethyan tectonic domain in the Pre-Cenozoic Period. They are formed on the background of the Paleo-Tethyan tectonic domain, and are important components of the Eastern Tethyan multi-island-ocean system. Three branches of t...

International Nuclear Information System (INIS)

The author applies the GO methodology to reliability analysis of the offsite power supply system of Daya Bay NPP. The direct quantitative calculation formulas of the stable reliability target of the system with shared signals and the dynamic calculation formulas of the state probability for the unit with two states are derived. The method to solve the fault event sets of the system is also presented and all the fault event sets of the outer power supply system and their failure probability are obtained. The resumption reliability of the offsite power supply system after the stability failure of the power net is also calculated. The result shows that the GO methodology is very simple and useful in the stable and dynamic reliability analysis of the repairable system

International Nuclear Information System (INIS)

The systems for which the algebra of gauge transformations in the lagrangian formalism is closed, are considered. The hamiltonian BRST charge and the BRST-invariant hamiltonian are found explicitly. Their expansions in powers of the ghost variables contain, in general, an infinite number of terms. (orig.).

UK PubMed Central (United Kingdom)

ObjectivesTo see whether there are age variations in the relationships between having a close companion friend at church, health, and outpatient physician visits.Full Text Available

Wastenet

...The system recognises the name and confirms it before it starts to dial. To stop the number being dialled say 'cancel'. If ...of the conference : Press the Recall 'R' button and listen for holding dial tone. Select extension or outside number of the person to ...who is going to join the conference Press Recall 'R' to receive dial tone and select '*' and '4'. The call is ...line is faulty and should be reported to the switchboard operators by dialling '0' and giving full details of the fault, the extension ...

Energy Technology Data Exchange (ETDEWEB)

A Vacuum Circuit Breaker demonstrated its ability to interrupt short circuits with faster than normal rates of rise of Transient Recovery Voltage (TRV) at levels greater than those produced by most transformer secondary faults. Two recent exploratory test programs evaluated the interrupting ability of a 15kV Vacuum Circuit Breaker containing interrupters of the rotating arc type with contacts made from a Chromium-Copper powder metal mixture. The interrupting conditions covered a wide range of currents from 10% to 130% of the 28kA rated short circuit current of the tested circuit breaker and a wide range of TRV rates of rise, including the relatively slow rate of rise, normally used in testing and found in most indoor circuit breaker applications; two faster rates of rise equaling and exceeding those found in a known power plant transformer secondary protection application; and the fastest rates of rise possible in the laboratory which exceed the requirements of ...

International Nuclear Information System (INIS)

A quadruply redundant synchronous fault tolerant processor (FTP) is now under fabrication at the C.S. Draper Laboratory to be used initially as a trip monitor for the Experimental Breeder Reactor EBR-II operated by the Argonne National Laboratory in Idaho Falls, Idaho. The real time operating system for this processor is described.

Energy Technology Data Exchange (ETDEWEB)

In this study, a probabilistic seismic risk analysis of the Wolsung NPP containment building was performed by a seismic hazard analysis and a seismic fragility analysis based on the nonlinear dynamic time-history analyses. The conventional seismic fragility analysis of the safety related structures in a NPP have been performed by using the linear elastic analysis results. The probabilistic seismic risk of the containment building was 5.19e-8.

Energy Technology Data Exchange (ETDEWEB)

Nine-component vertical seismic profiling has been conducted at the UE-25 UZ No. 16 borehole at Yucca Mountain, Nevada, in support of investigation of the hydrologic significance of fault and fracture systems. A large data set from multi-component sources and receivers allows state-of-the-art advances in processing using polarization filtering and reverse time migration, for enhanced interpretation of geologic features.

International Nuclear Information System (INIS)

For the CREYS MALVILLE plant, sodium natural convection has been considered in connection with certain upset, faulted or beyond design basis situations. For each of these cases, this paper will discuss why natural convection was considered, the main conclusions reached and the natural convection tests which will be performed at plant start-up.

Science.gov (United States)

Precambrian gneisses in the San Bernardino Mountains were first identified and described in the vicinity of Baldwin Lake by Guillou (1953). Five lithologic units mappable at 1:24,000 scale are recognized: biotite [+-] muscovite quartzofeldspathic gneiss, amphibolite, pyroxene metagabbro, augen gneiss, and biotite [+-] muscovite granitic gneiss. Baldwin gneiss with this L Baldwin Lake, the gneissic fabric is rotated toward the northwest, subparallel to the Doble fault. Along this fault, Baldwin gneiss is structurally underlain by overturned Paleozoic quartzite and marble (Zabriskie Quartzite and Carrara Formation). Regional relations suggest that the Doble fault is a northeast-directed basement thrust fault of pre-Late Cretaceous age, and may be contemporaneous with late Paleozoic deformation and metamorphism of Paleozoic rocks further west in the range. Field relations suggest that Baldwin gneiss in its ...

Energy Technology Data Exchange (ETDEWEB)

Due to the fast cooling of steam turbines, the shutdown time during maintenance or when repairing faults and damage can be shortened. This booklet describes various processes for cooling steam turbines. It is recommended that fast cooling should be planned in designing new plants and corresponding arrangements should be provided in the form of pipe connections and valves. (DG).

Energy Technology Data Exchange (ETDEWEB)

We propose a novel scheme for scalable solid state quantum computing, where superconducting microwave transmission line resonators (cavities) are arranged in a two-dimensional grid on the surface of a chip, coupling to superconducting qubits (charge or flux) at the intersections. We analyze how tasks of quantum information processing can be implemented in such a topology, including efficient two-qubit gates between any two qubits on the grid and elements of fault-tolerant computation.

Science.gov (United States)

Dec 12, 2007 ... This is an artist concept of a close-up view of Saturn's ring particles.

Energy Technology Data Exchange (ETDEWEB)

The process of inelastic scattering of hot plasma electrons with energies upto 3 keV by a pair of close-lying nuclear levels (..delta../ital E/less than or equal to2keV), one of whichis isomeric, is discussed. The transition cross sections in the nuclei/sup 242/Am, /sup 171/Lu, and /sup 73/Se are calculated. Estimates of the numberof isomeric nuclei de-excited as a result of electron-stimulated processes in aplasma with parameters characteristic of present-day experiments in controlledthermonuclear fusion are given.

Science.gov (United States)

... closely correlated to the amount of re- centration. The molar extinction coefficients were agent added to the enzyme. The naphtha- ...

Energy Technology Data Exchange (ETDEWEB)

In this thesis a study is made of the of voltage characteristics and reactive power control in the transmission network of the Electric Power Systems (EPS) with static compensators of VARs (SCVs). The necessity of voltage and reactive power control and the application of SCVs as a solution means for three representative operation stages of the EPS, considering balanced operation conditions and fundamental frequency is analyzed: Operation in the presence of incremental voltage changes, quasi-stationary operation or steady state and behavior at the occurrence of big disturbances. The application of SCVs to systems of integral transmission is in general a closed loop control system, reason why the analysis of the interaction of the system EPS-SCV is considered as an essential part of the voltage and reactive power control study. Firstly, the response analysis of the control loop is made for incremental voltage changes, representing the power system by means of its ...

Energy Technology Data Exchange (ETDEWEB)

The U.S. Department of Energy (DOE) is interested in developing tools and methods for potential U.S. use in designing and evaluating safeguards systems. For this goal several DOE National Laboratories are defining the characteristics of typical facilities of several size scales, and the safeguards measures and instrumentation that could be applied. Lawrence Livermore National Laboratory is providing systems modeling and analysis of facility and safeguards operations, diversion path generation, and safeguards system effectiveness. The constituent elements of diversion scenarios are structured using directed graphs (digraphs) and fault trees. Safeguards indicator probabilities are based on sampling statistics and/or measurement accuracies. Scenarios are ranked based on value and quantity of material removed and the estimated probability of non-detection. Significant scenarios, especially those involving timeliness or randomly varying order of events, are transferred ...

International Nuclear Information System (INIS)

Computer based control systems for safety related applications in nuclear power plants have to meet not only the functional, performance and interface requirements, they in addition, have to meet regulatory requirements like enhanced reliability, safety and security and should provide fault tolerance, diagnostics and self-supervision. The control system architecture, hardware design and software design should meet requirements as specified in design code and guides of AERB. The Dual Processor Hot Standby Process Control System (DPHS-PCS) for TAPP-3 and 4 is a safety related (Class- IB) system. DPHS-PCS regulates PHT pressure, Pressuriser pressure, Pressuriser level, Bleed condenser pressure, Bleed condenser level and Steam generator pressure. The performance, reliability and safety requirements of this control system are met by employing a fault tolerant computer configuration developed for this purpose using hardware designed with facility for ...

International Nuclear Information System (INIS)

Localized deformation may play a key role in the underlying mechanism of irradiation assisted stress corrosion cracking (IASCC) in light water reactor core components. In this study, four austenitic alloys, 18Cr8Ni, 15Cr12Ni, 13Cr15Ni and 21Cr32Ni, with different stacking fault energies were irradiated to 1 and 5 dpa at 360 deg. C using 3.2 MeV protons. Interrupted constant extension rate tensile (CERT) tests were conducted in a simulated BWR environment to determine IASCC susceptibility. In order to characterize the localized deformation in slip channels and grain boundaries, parallel CERT experiments were also performed in an argon atmosphere. Results show that the IASCC susceptibility of the tested alloys increases with increasing irradiation dose and decreasing stacking fault energy. IASCC tends to initiate at locations where slip channels intersect grain boundaries. Localized deformation in the form of grain boundary sliding due to the ...

Energy Technology Data Exchange (ETDEWEB)

The geology and hydrology of the reference New Production Reactor (NPR) site at Savannah River Site (SRS) have been summarized using the available information from the NPR site and areas adjacent to the site, particularly the away from reactor spent fuel storage site (AFR site). Lithologic and geophysical logs from wells drilled near the NPR site do not indicate any faults in the upper several hundred feet of the Coastal Plain sediments. However, the Pen Branch Fault is located about 1 mile south of the site and extends into the upper 100 ft of the Coastal Plain sequence. Subsurface voids, resulting from the dissolution of calcareous portions of the sediments, may be present within 200 ft of the surface at the NPR site. The water table is located within 30 to 70 ft of the surface. The NPR site is located on a groundwater divide, and groundwater flow for the shallowest hydraulic zones is predominantly toward local streams. Groundwater flow in ...

Energy Technology Data Exchange (ETDEWEB)

The paper describes the application of Fuzzy Power System Stabilizer(FPSS) for improving dynamic stability of power system. The Real-coding Genetic Algorithm(RGA) was applied to optimize gains of the inputs and outputs of the FPSS. The effectiveness of the proposed FPSS was demonstrated by simulation studies for single-machine infinite system. To show the superiority of the proposed FPSS, its performances were compared with those of Conventional Power System Stabilizer (CPSS). The proposed FPSS showed better control performances than the CPSS in three-phase ground fault under a normal load which was system condition in tuning FPSS. To show the robustness of the proposed FPSS, it was applied to damp the low frequency oscillations caused by disturbances such as three-phase ground fault under heavy and light load conditions. The proposed FPSS showed better performance than CPSS in terms of the settling time and damping effect for power system ...

Energy Technology Data Exchange (ETDEWEB)

Whenever moving surfaces interact, wear particles are produced. Microscopic examination of the morphology of such wear debris is an accepted method for machine condition monitoring and fault diagnosis. Wear particle analysis has not, however, been widely accepted in industry because it is dependent on expert interpretation of particle morphology and relies on subjective assessment criteria. Consequently, the methods are time consuming and expensive and are not always consistent. The use of automated computer image analysis systems to assess the morphology of debris promises to overcome these limitations by making the methods more time and cost efficient, and also more consistent and effective. The first step required for automation of the analysis procedure is to develop objective criteria for assessing the wear particle morphology. Numerical parameters to describe the morphology have been developed and are outlined in this paper. A system using such techniques ...

Energy Technology Data Exchange (ETDEWEB)

The northeastern part of the Great Divide basin is a separate, unique, and until recently, little-explored subbasin sometimes called the Bison basin. It is bounded by the Wind River Mountains, Sweetwater-Granite Mountain foreland uplift, Lost Soldier-Wertz structure, and a little-studied very positive east-west structural arch approximately coincident with the Sweetwater-Fremont county line. A comprehensive seismic, Landsat, and subsurface geologic examination or, better, dissection of the Bison basin was initiated in 1978. Numerous oil and gas prospects were delineated by this study. Since this small, 12 by 40 mi (19 by 64 km) basin is bordered by known reserves of 260 million bbl of oil and 90 million bcf of gas, these prospects proved to be a popular target of the drill bit. At least one of these prospects appears to be productive; others are currently being drilled. The presence of major east-west wrench faults, a well-documented foreland uplift, until recently ...

Energy Technology Data Exchange (ETDEWEB)

Modified Ostwald ripening theory is used to calculate the time evolution of the size distribution function of extended end-of-range defects in ion implanted silicon. This allows the authors to compare the time dependent self-interstitial supersaturation during post-implantation annealing in the presence of Frank-type stacking faults with that in the presence of {l_brace}311{r_brace}-defects. It is shown that the latter affect self-interstitial concentrations up to the point where they dissolve whereas the former are irrelevant from the point of view of transient enhanced diffusion.

Energy Technology Data Exchange (ETDEWEB)

Copper alloys are a suitable tubing material for turbine condensers and heat exchangers. Due to problems with corrosions copper alloys increasingly are displaced by high-grade steel and titanium. Blockages and surface formation in the pipes, disturbance of the oxide coating formation, erosion and quality faults with the production are the causes for the corrosion. In the contribution under consideration counter measures are designated for the solution of the problems with corrosions. The application limits for different copper alloys are designated. Recommendations for the optimized operation are given.

Energy Technology Data Exchange (ETDEWEB)

Artificial Neural Networks (ANNs) are parallel distributed processing machines. The unique characteristics of ANNs are: Fault tolerance, robustness, plasticity and generalization. These offer great potential in many AI applications such as character recognition. Handwritten character recognition is an intrinsically interesting problem, but the difficulties of this task are the many variations in the characters. A robust new incremental learning method, which combines supervised and unsupervised learning paradigms implemented by the Functional Link Net, is illustrated with experimental results. Clustering, based on unsupervised learning, classifies the input data into several categories. The supervised learning paradigm then further classifies the data in the clustered categories.

International Nuclear Information System (INIS)

A statistical evaluation of rotor blade damage in axial steam turbines affords an insight into the extent of the repair costs incurred and reveals the types of defects and shortcomings which cause such damage. The great amount of rotor blade damage discovered during control inspections will surprise even many turbine experts. The statistical evaluation is followed by a review of the more frequent causes of damage and their characteristic features, illustrated on the basis of practical examples. This contribution is intended as an aid to both the manufacturers and operators of steam turbines in preventing the oft almost classic types of faults which constantly recur. (orig.).

Energy Technology Data Exchange (ETDEWEB)

The Pequop Mountains (PM), Wood Hills (WH) and East Humboldt Range (EHR), NE Nevada, provide evidence that the hinterland of the Sevier thrust belt experienced large-magnitude Mesozoic shortening ([>=]55 km) and crustal thickening ([>=] 30 km). These ranges expose a structurally continuous crustal cross section of unmetamorphosed to high pressure upper amphibolite facies Triassic to Precambrian miogeoclinal strata. This sequence lies structurally beneath unmetamorphosed extensional klippen that omit metamorphic grade and crustal section, but also repeat stratigraphic units. Because they repeat stratigraphic units, the underlying miogeoclinal section, or footwall, must have once lain beneath a thrust fault (herein named the Windermere thrust). The footwall of the Windermere thrust was exhumed by two generations of top-to-the-W-NW low-angle normal faults that are distinguished by whether they are depositionally overlapped by Eocene volcanic ...

Energy Technology Data Exchange (ETDEWEB)

The island of Hispaniola (Dominican Republic and Haiti) lies within the North Caribbean strike-slip plate boundary zone. The post-Eocene history of Hispaniola is marked by strike-slip accretion of crustal fragments onto a Late Cretaceous-Eocene island arc. Three onshore Neogene clastic basins have been the focus of petroleum exploration in Hispaniola. Oil production was achieved by drilling surface anticlines in the Azua Basin in South-Central Hispaniola (Dominican Republic) during World War II (Maleno and Higuerito fields). More modern seismic exploration has been carried out in the Enriquillo, San Juan and Cibao Basins, but has not resulted in production. Recent surface and seismic stratigraphic mapping has elucidated the geologic history of Southern Hispaniola. It consists of several Late Cretaceous-Eocene oceanic and island-arc terranes separated by E-W to NW/SE-striking ''ramp'' or thrust-bound clastic basins of Neogene age (San Juan, Azua and ...

Energy Technology Data Exchange (ETDEWEB)

The Sperchios Basin is an active asymmetric graben, bounded to the south by a major border fault system with major fault segments typically 20-30 km long. The basin is dominated by a major axial fluvio-deltaic system which enters the partially enclosed Maliakos Gulf to the east. Lateral sourced depositional systems within the basin comprise hanging-wall and footwall-derived alluvial fans and a narrow coastal plain along the footwall scarp bordering the Maliakos Gulf. High resolution seismic data from the Maliakos Gulf reveals three late Quaternary progradational parasequences sourced from axial and lateral depositional systems, with a regional late-Pleistocene transgressive surface dated at circa. 10 ka BP within the Maliakos Gulf. Differential subsidence of the late Pleistocene transgressive surface indicates marked variation in subsidence from 2.4 m ka{sup -1} at fault segment centers to 0.8 m ka{sup -1} at segment ...

Energy Technology Data Exchange (ETDEWEB)

Rock fracture characterization documents a total of 1496 fractures in unit 2 of the Tshirege Member of the Bandelier Tuff along 6013 feet of Los Alamos Canyon`s north wall adjacent to Operational Unit 1098. Geologically termed joints, these fractures likely owe their primary origin to brittle failure during the cooling contraction of the tuff after its emplacement nearly 1 million years ago. Subsequent tectonic movement along the Pajarito Fault system has modified fracture strikes, dips, apertures, and linear density. From a background linear density of approximately 20 fractures per 100-foot interval along the canyon wall, fracture density increases to values in excess of 50 fractures per 100-foot interval in a zone at and immediately east of the Omega West reactor building TA-2-1. This increase in fracture density is coincident with the mapped trace of the Guaje Mountain Fault (GMFZ) that apparently bifurcates with a branch running through ...

British Library Electronic Table of Contents (United Kingdom)

Globalization and technological innovation are creating dynamic networks or chains of interconnected players, often known as value delivery networks or supply chains, in which a firm, whether manufacturing or service, holds the key to creating and delivering value in the form of offerings to the customers. This idea of value creation and exchange is the foundation stone of relationship marketing and it is considered successful when closeness is said to have been established in the relationship which subsequently leads toward the achievement of objectives. In order to study and understand the creation of value through relationship closeness in a value delivery network particularly at the backward end, a literature review is conducted. A framework is further developed with the help of Interp...

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A process for the production of transportation fuels from heavy hydrocarbonaceous feedstock is provided comprising a two-stage, close-coupled process, wherein the first stage comprises a hydrothermal zone into which is introduced a mixture comprising a feedstock and metals-impregnated red mud having coke-suppressing and demetalizing activity, and hydrogen; and the second, close-coupled stage comprises a hydrocatalytic zone into which substantially all the effluent from the first stage is directly passed and processed under hydrocatalytic conditions. The preferred metals for impregnation include transition metals, in particular, nickel and molybdenum.

International Nuclear Information System (INIS)

We consider a D-brane probe in the unstable string background associated with flux branes. The twist in the spacetime metric reponsible for supersymmetry breaking is shown to manifest itself in the mixing of open Wilson lines with the phases of some adjoint matter fields, resulting in a nonlocal and nonsupersymmetric form of Yang-Mills theory as the probe dynamics. This provides a setup where one can study the fate of a large class of unstable closed string theories that includes as a limit type 0 theories and various orbifolds of type II and type 0 theories. We discuss the limit of C/Z_n orbifold in some detail and speculate on the couplings with closed string tachyons.

Science.gov (United States)

... At no time must any solution or water temper- atures exceed 72°F, with all fluids maintained as close as possible to 700F. ...

Science.gov (United States)

Jan 26, 2005 ... Heavy snow settled over Iran on January 23, 2005, closing roads and ... Located along the southern front of the Alborz mountains, Iran's ...

UK PubMed Central (United Kingdom)

Social organisms that cooperate with some members of their own species, such as close relatives, may fail to cooperate with other genotypes of the same species. Such noncooperation may take the form...Full Text Available

Science.gov (United States)

... is reduced: 1) by lack of oxygen, 2) in hypercapnia associated with closed rooms or tents, 3) by use of sleeping drugs, antipyretics, insulin, and 4 ...

Energy Technology Data Exchange (ETDEWEB)

We study how the effect of closed-string tachyon condensation can enter into the on-shell effective action of open-string tachyons in the bosonic case. We also consider open-string one-loop quantum corrections to the on-shell action. We use a sigma-model approach with boundary terms, and we utilize some results of boundary string field theory (BSFT) to define the on-shell effective action. We regard D-instanton-like objects with appropriate weight as closed-string tachyon tadpoles, and we insert them into worldsheets to analyze the effect of closed-string tachyons. (author)

Energy Technology Data Exchange (ETDEWEB)

Fact sheet written for the NICE3 Program on a new chlorine-free process for pulping and bleaching wastewater.

Energy Technology Data Exchange (ETDEWEB)

Microscopic non-energy weighted sum-rules for the total rates of the neutrinoless ..mu..-e conversion process are constructed in the frame of the shell model for closed shell nuclei. For non-closed shell nuclei the relevant rates were obtained by interpolation. Also the contribution of the coherent process to the total ..mu..-e conversion rate is calculated and discussed.

International Nuclear Information System (INIS)

We describe exact cosmological solutions with rotation and expansion in the low-energy effective string theory. These models are spatially homogeneous (closed Bianchi type IX) and they belong to the family of shear-free metrics which are causal (no closed timelike curves are allowed), admit no parallax effects and do not disturb the isotropy of the background radiation. The dilaton and the axion fields are nontrivial, in general, and we consider both cases with and without the central charge (effective cosmological constant).

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We describe a global closed orbit feedback experiment, based upon a real time harmonic analysis of both the orbit movement and the correction magnetic fields. The feedback forces the coefficients of a few harmonics near the betatron tune to vanish, and significantly improves the global orbit stability. We present the results of the experiment in the UV ring using 4 detectors and 4 trims, in which maximum observed displacement was reduced by a factor of between 3 and 4. 4 refs., 3 figs.

Energy Technology Data Exchange (ETDEWEB)

We apply Hawking's proposal for the initial state of the Universe to a rotating Bianchi type-IX minisuperspace model in order to examine the problem of rotation in a closed cosmology. Using the Feynman path-integral techniques instead of the Wheeler-DeWitt equation, we are able to say that for a small angular velocity the closed Friedmann-Robertson-Walker model is indeed the most probable initial state for the Universe.

Energy Technology Data Exchange (ETDEWEB)

The free energy of a gas of closed strings with extrinsic curvature (smooth strings) is evaluated on a torus. This is compared with the free energy of a collection of free particles, and hence the mass spectrum of excitations of the smooth strings is deduced. It is found that above a critical value of the coupling constant of the curvature term the spectrum is free of tachyons. Furthermore, there are no massless spin-2 excitations. The absence of massless spin-2 fields is a consequence of the fact that the smooth-string theory is not modular invariant.

CERN Document Server

We give a closed formula for volumes of generic hyperbolic tetrahedra in terms of edge lengths. The cue of our formula is by the volume conjecture for the Turaev-Viro invariant of closed 3-manifolds, which is defined from the quantum 6j-symbols. This formula contains the dilogarithm functions, and we specify the adequate branch to get the actual value of the volumes.

Energy Technology Data Exchange (ETDEWEB)

Daylight responsive dimming systems have been used in few buildings to date because they require improvements to improve reliability. The key underlying factor contributing to poor performance is the variability of the ratio of the photosensor signal to daylight workplane illuminance in accordance with sun position, sky condition, and fenestration condition. Therefore, this paper describes the integrated systems between automated roller shade systems and daylight responsive dimming systems with an improved closed-loop proportional control algorithm, and the relative performance of the integrated systems and single systems. The concept of the improved closed-loop proportional control algorithm for the integrated systems is to predict the varying correlation of photosensor signal to daylight workplane illuminance according to roller shade height and sky conditions for improvement of the system accuracy. In this study, the performance of the ...

International Nuclear Information System (INIS)

The purposes of this report are (1) to perform a Verification and Validation (V and V) test for the VIPEX(Vital-area Identification Package EXpert) software and (2) to improve a software quality through the V and V test. The VIPEX was developed in Korea Atomic Energy Research Institute (KAERI) for the Vital Area Identification (VAI) of nuclear power plants. The version of the VIPEX which was distributed is 3.2.0.0. The VIPEX was revised based on the first V and V test and the second V and V test was performed. We have performed the following tasks for the V and V test on Windows XP and VISTA operating systems: ? Testing basic functions including fault tree editing ? Testing all kind of functions ? Research for update from Visual BASIC 6.0 to Visual BASIC 2008

Energy Technology Data Exchange (ETDEWEB)

This report reviews system safety analysis methods and examines their application to nuclear waste management systems. The safety analysis methods examined include expert opinion, maximum credible accident approach, design basis accidents approach, hazard indices, preliminary hazards analysis, failure modes and effects analysis, fault trees, event trees, cause-consequence diagrams, G0 methodology, Markov modeling, and a general category of consequence analysis models. Previous and ongoing studies on the safety of waste management systems are discussed along with their limitations and potential improvements. The major safety methods and waste management safety related studies are surveyed. This survey provides information on what safety methods are available, what waste management safety areas have been analyzed, and what are potential areas for future study.

Energy Technology Data Exchange (ETDEWEB)

Natural fractures and in situ stresses commonly dictate subsurface reservoir permeability and permeability anisotropy, as well as the effectiveness of stimulation techniques in low-permeability, natural gas reservoirs. This paper offers an initial prediction for the orientations of the fracture and stress systems in the tight gas reservoirs of the Frontier Formation, in the Green River basin of southwestern Wyoming. It builds on a previous report that addressed fractures and stresses in the western part of the basin and on ideas developed for the rest of the basin, using the principle that thrust faults are capable of affecting the stress magnitudes and orientations in little-deformed strata several hundreds of kilometers in front of a thrust. The prediction of subsurface stresses and natural fracture orientations is an undertaking that requires the willingness to revise models as definitive data are acquired during drilling. The predictions made in this paper are ...

Energy Technology Data Exchange (ETDEWEB)

In this book are found technical and scientific papers on the main works of the Direction of the Fuel Cycle (DCC) in France. The study fields are: the up-side of the nuclear fuel cycle with theoretical studies (plasma simulation) and technological developments and instrumentation (lasers diodes, carbides plasma projection, carbon 13 enrichment); the down-side nuclear fuel cycle with theoretical studies (ion Eu{sup 3+} complexation simulation, decay simulation, uranium and plutonium diffusion study, electrolyser operating simulation), scenario studies ( recycling, wastes management), experimental studies; dismantling and cleaning (soils cleaning, surface-active agent for decontamination, fault tree analysis); analysis with expert systems and mass spectrometry. (A.L.B.)

Energy Technology Data Exchange (ETDEWEB)

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.

International Nuclear Information System (INIS)

Level 1 and 2 probabilistic safety assessments (PSAs) for both internal and external events are being performed to meet one of the conditions for a construction permit for Wolsong units 2, 3, and 4 in Korea. These units are CANDU-6 Pressurized Heavy Water Reactors (PHWRs), and the study is the first comprehensive level 1 and 2 PSAs for CANDU type plants in the world. The detailed PSA includes and extensive fault tree, event tree analysis, human reliability analysis, and common cause failure analysis. Event trees have been developed for 35 internal initiating event groups. The preliminary results show that the total core damage frequency for Wolsong units 2, 3, and 4 each is similar to that for a typical PWR plant. (author).

Energy Technology Data Exchange (ETDEWEB)

The fault-bounded Stellarton Basin of northern Nova Scotia, Canada, contains the Province's largest oil shale resources (estimated at 825 {times} 10{sup 6} tons with 168 {times} 10{sup 6} bbls of shale oil in situ). The oil shales were first discovered in the 1850s and, except for limited scale mining during 1852-1859 and 1929-1930, they have remained undeveloped. In order to assess the potential economic use of the oil shales, a comprehensive study incorporating geological field mapping, core-logging, organic and inorganic geochemistry, organic petrology and combustion performance testing was undertaken. Results are presented.

International Nuclear Information System (INIS)

The use of X-ray diffraction line profile analysis for the study of nanocrystalline powders is described. The fundamentals of the theory are presented in terms of crystallite/domain size, size distribution, lattice distortion, dislocations density and stacking faults. Line profile parameters and the methods of pattern fitting introduced to overcome the diffraction-line overlap problem are discussed. The approaches based of the integral breadth of the measured line profiles and the Fourier method are discussed. In addition, simplified approaches are also commented. Representative examples are selected to illustrate various cases of microstructure, such as nanomaterials with strain-free spherical nano crystallites, strain-free crystallites with anisotropic crystallite shape, anisotropic crystallites with microstrains and spherical crystallites with dislocation densities and crystallite size distributions. (author)

Energy Technology Data Exchange (ETDEWEB)

Analytical and numerical methods have been used in this investigation to model the behavior of geothermal systems under exploitation. The work is divided into three parts: (1) development of a numerical code, (2) theoretical studies of geothermal systems, and (3) field applications. A new single-phase three-dimensional simulator, capable of solving heat and mass flow problems in a saturated, heterogeneous porous or fractured medium has been developed. The simulator uses the integrated finite difference method for formulating the governing equations and an efficient sparse solver for the solution of the linearized equations. In the theoretical studies, various reservoir engineering problems have been examined. These include (a) well-test analysis, (b) exploitation strategies, (c) injection into fractured rocks, and (d) fault-charged geothermal reservoirs.

Energy Technology Data Exchange (ETDEWEB)

Diagnostic systems make it possible to recognize incipient faults in good time and help to increase the availability of power stations. The thermal efficiency and the effective terminal output are didicated by a number of influences. Deviations from the expected status can be identified via continuous recording of the operating parameters and calculation of derived data. An improved efficiency and economical load distribution lead to considerable cost savings. (orig.) [Deutsch] Die Verarbeitung von Messwerten und Signalen ermoeglicht eine umfassende Beurteilung des Anlagenzustandes und die Erkennung sich anbahnender Veraenderungen. Stoerungen, Schaeden oder eine unwirtschaftliche Betriebsweise koennen fruehzeitig erkannt werden. Erhoehte Verfuegbarkeit, geringerer Brennstoffverbrauch und optimierte Lastaufteilung bringen Kostenvorteile. (orig.)

International Nuclear Information System (INIS)

Nanocrystalline powders of GaN with grain sizes ranging from 2 to 30 nm were examined under high external pressures by in situ diffraction techniques in a diamond anvil cell at DESY (HASYLAB, Station F3). The experiments on densification of pure powders under high pressure were performed without a pressure medium. The mechanism of generation and relaxation of internal strains and their distribution in nanoparticles was deduced from Bragg reflections recorded in situ under high pressures at room temperature. The microstrain was calculated from the full-width at half-maximum (FWHM) values of the Bragg lines. It was found that microstrains in GaN crystallites are generated and subsequently relaxed by two mechanisms: generation of stacking faults and change of the size and shape of the grains occurring under external stress. (author)

Energy Technology Data Exchange (ETDEWEB)

This paper presents a new method and newly developed stabilizing equipment to prevent the loss of synchronism of generators in pumped-storage plants from spreading. The proposed method includes functions to estimate the swing of each generator by using on-line generator output sampled at a rate of 600 times per second after an occurrence of disturbance such as fault, faulty equipment and so on, to predict generator swing 200-300 milliseconds ahead and loss of synchronism between generators in pumped-storage plants and those in thermal and nuclear plants, and to decide the number of generators that must be shed to maintain stability. Tokyo Electric Power Co. (TEPCO) installed the newly developed stabilizing equipment based on this method in the power system in June, 1986.

CERN Document Server

Entanglement is the essential quantum resource for a potential speed-up of information processing, as well as for sophisticated quantum communication. Quantum information networks will be required to convey information from one place to another, by using entangled light beams. Many physical systems are under consideration as building blocks, with different merits and faults, so that hybrid systems are likely to be developed. Here we present an important tool for connecting systems that share no common resonance frequencies: we demonstrate the first direct generation of entanglement among more than two bright beams of light, all of different wavelengths (532.251 nm, 1062.102 nm, and 1066.915 nm). We also observe, for the first time, disentanglement for finite channel losses, the continuous variable counterpart to entanglement sudden death.

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Critical current density and dissipation of four sintered YBCO filaments were measured using a continuous DC power supply. Each sample exhibited somewhat different characteristics from the others even though 3 of the 4 samples are from the same batch. The data suggest that it is possible for the YBCO filament to be in a state of stable equilibrium when part of the filament is in the flux-flow state and part of the filament is in the normal state (local hot spots). This behavior may be advantageous for resistive fault current limiters because the intermediate state (partly flux-flow and partly normal) has an overall resistance much higher than that of the flux-flow state but it does not lead to thermal runaway (burnout) or excessive heating compared to a YBCO filament driven into normal state over its entire length. Two of the samples were broken as a result of local burnout.

Energy Technology Data Exchange (ETDEWEB)

In Niigata University Hospital, most of conventional radiography were changed to Fuji computed Radiography (FCR) from July 1988. To evaluate its clinical utility, questionnaires relating to FCR image were distributed to all physicians including non-radiologists in the hospital after three months. The ratio of the physicians evaluated FCR image to be better than conventional image was 75% in chest radiography, 64% in abdominal radiography. FCR tomography of bone, joint, cranium and chest was also evaluated to be better than conventional by most of the physicians. Reduced size of the film and difficulty in detecting interstitial shadows of the lung were mentioned to be the fault of FCR. (author).

British Library Electronic Table of Contents (United Kingdom)

Harmonics bred from loads are mainly odd order because the current waveforms have half-wave symmetry. Since the even harmonics are negligibly small, they generally are not measured in electric power systems. However, even harmonics were measured at a 500/275/154 kV substation in Hokuriku Electric Power Company after a transmission line fault was corrected. The even harmonics caused malfunctions of protective digital relays because the relays used 4th harmonics at the input filter as the automatic supervisory signal. This paper describes mechanisms of generation of the even harmonics by comparing the measured waveforms with the ATP-EMTP simulation results. Analysis of these results has clearly shown that there are three different mechanisms of generation of even harmonics. The first mechani...

British Library Electronic Table of Contents (United Kingdom)

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 ...

Energy Technology Data Exchange (ETDEWEB)

In this paper, we have designed power system stabilizer (PSS) using object-oriented method. There are several types of power system stabilizer, A proportional-integral (PI) controller is very simple for practical implementation. Therefore it has been widely employed by the industry. The methods of obtaining the gains (Ki,Kp) of PI controller are root-locus method and sub-optimal regulator approach. But these methods are cannot be applicable to nonlinear system and faulted power system. So we proposed a new method which can be applied to nonlinear system by numerical analysis method. The method of dynamic system simulation by numerical method is very difficult and complex. We proposed flexible simulation method for complex power system analysis using object-oriented programming (OOP) and applied to PI controller design. (author). 7 refs., 14 figs., 2 tabs.

Energy Technology Data Exchange (ETDEWEB)

We study systems of multiple localized closed string tachyons and the phenomena associated with their condensation, in C{sup 3}/Z{sub N} non-supersymmetric noncompact orbifold singularities using gauged linear sigma model constructions, following hep-th/0406039. Our study reveals close connections between the combinatorics of non-supersymmetric flip transitions (between topologically distinct resolutions of the original singularity), the physics of tachyons of different degrees of relevance and the singularity structure of the corresponding residual endpoint geometries. This in turn can be used to study the stability of the phases of gauged linear sigma models and gain qualitative insight into the closed string tachyon potential. (author)

Energy Technology Data Exchange (ETDEWEB)

Off-shell interactions for localized closed-string tachyons in C/Z{sub N} superstring backgrounds are analyzed and a conjecture for the effective height of the tachyon potential is elaborated. At large N, some of the relevant tachyons are nearly massless and their interactions can be deduced from the S-matrix. The cubic interactions between these tachyons and the massless fields are computed in a closed form using orbifold CFT techniques. The cubic interaction between nearly-massless tachyons with different charges is shown to vanish and thus condensation of one tachyon does not source the others. It is shown that to leading order in N, the quartic contact interaction vanishes and the massless exchanges completely account for the four point scattering amplitude. This indicates that it is necessary to go beyond quartic interactions or to include other fields to test the conjecture for the height of the tachyon potential.

CERN Document Server

We investigate the equivariant cohomology of the natural torus action on a K-contact manifold and its relation to the topology of the Reeb flow. Using the contact moment map, we show that the equivariant cohomology of this action is Cohen-Macaulay, which is a generalization of equivariant formality for torus actions without fixed points. As a consequence, a generic component of the contact moment map is a perfect Morse-Bott function for the basic cohomology of the orbit foliation F of the Reeb flow. Assuming that the closed Reeb orbits are isolated, we show that the basic cohomology of F is trivial in odd degrees, and its dimension equals the number of closed Reeb orbits. We characterize the K-contact manifolds with minimal number of closed Reeb orbits as real cohomology spheres. We also prove a GKM type theorem for K-contact manifolds, which allows us to calculate the equivariant cohomology algebra of K-contact manifolds ...

International Nuclear Information System (INIS)

We conjecture that the end point of bulk closed string tachyon decay at any nonzero coupling is the annihilation of space-time by Witten's bubble of nothing, resulting in a topological phase of the theory. In support of this we present a variety of situations in which there is a correspondence between the existence of perturbative tachyons in one regime and the semiclassical annihilation of space-time. Our discussion will include many recently investigated scenarios in string theory including Scherk-Schwarz compactifications, Melvin magnetic backgrounds, and noncompact orbifolds. We use this conjecture to investigate a possible web of dualities relating the eleven-dimensional Fabinger-Horava background with nonsupersymmetric string theories. Along the way we point out where our conjecture resolves some of the puzzles associated with bulk closed string tachyon condensation.

UK PubMed Central (United Kingdom)

Nine patients with renal osteodystrophy were tested for 6.5 to 35 months with 1,25-dihydroxycholecalciferol (1,25-DHCC). A close biochemical follow-up was performed during the first 6 months of treatment,...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The goal of this DOE-supported exhibition is to demystify Einstein`s formula E = mc{sup 2} by illustrating the interchangeability of matter (m) and energy (E), c{sup 2} being the exchange rate. The exhibition has two major parts, {open_quotes}matter into energy{close_quotes} and {open_quotes}energy into matter{close_quotes}, plus a video to connect them. {open_quotes}Matter into energy{close_quotes} has now been completed and has been placed on the museum floor. Positrons from a {sup 22}Na source are annihilated to produce gamma rays that are caught in NaI detectors. The viewer can alter the alignment of the detectors and observe the consequences for the rates of single and coincident counts. The viewer can also observe the effects of placing absorbers in front of the counters. Prototype explanatory graphics were placed around the exhibit and those will probably be changed after we have some experience with their ...

UK PubMed Central (United Kingdom)

Peptide toxins with high affinity, divergent pharmacological functions, and isoform-specific selectivity are powerful tools for investigating the structure-function relationships of voltage-gated...Full Text Available

UK PubMed Central (United Kingdom)

OBJECTIVES: To reassess the risk of leukaemia associated with residential exposure near high voltage transmission electric lines of 49 kV and above in view of the recent publications. METHODS: Through...Full Text Available

UK PubMed Central (United Kingdom)

Measurements were made of ⁴⁵Ca influx into isolated internodal cells of Chara corallina and also into internodal cells of intact plants. ⁴⁵Ca influx was closely...Full Text Available

UK PubMed Central (United Kingdom)

1. The penicillinases formed by penicillinase-constitutive mutant strains from two closely related varieties (749 and 6346) of Bacillus licheniformis have been isolated, characterized...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

It is proven that there do not exist any diagonal Bianchi type-IX universes which expand for an infinite time, provided only that the matter satisfies the dominant energy condition and has non-negative average principal pressures.

Science.gov (United States)

... POSITION VACANT: Program Manager (Advance Materials and Manufacturing), AD-340-4. Salary ranges from ... POTENTIAL: Program Manager (Advanced Materials and Manufacturing), AD-340-4. LOCATION: Directorate ...

UK PubMed Central (United Kingdom)

Prenatal cocaine exposure produces sustained neurobehavioral and brain synaptic changes closely resembling those of animals with defective alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic...Full Text Available

CERN Document Server

Femtocells are assuming an increasingly important role in the coverage and capacity of cellular networks. In contrast to existing cellular systems, femtocells are end-user deployed and controlled, randomly located, and rely on third party backhaul (e.g. DSL or cable modem). Femtocells can be configured to be either open access or closed access. Open access allows an arbitrary nearby cellular user to use the femtocell, whereas closed access restricts the use of the femtocell to users explicitly approved by the owner. Seemingly, the network operator would prefer an open access deployment since this provides an inexpensive way to expand their network capabilities, whereas the femtocell owner would prefer closed access, in order to keep the femtocell's capacity and backhaul to himself. We show mathematically and through simulations that the reality is more complicated for both parties, and that the best approach depends heavily ...

UK PubMed Central (United Kingdom)

Mitochondrial DNA is constantly exposed to oxidative injury. Due to its location close to the main site of reactive oxygen species, the inner mitochondrial membrane, mtDNA is more susceptible...Full Text Available

UK PubMed Central (United Kingdom)

Species that depend on ephemeral habitat often evolve distinct dispersal strategies in which the propensity to disperse is closely integrated with a suite of morphological, behavioural and physiological...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

We investigate terms with four derivatives in the low-energy action of closed Bose strings. Our analysis is consistent with the possibility that the action involves only curvatures of an affine connection with torsion. The torsion is provided by the antisymmetric tensor gauge field.

Science.gov (United States)

| Site Index open all | close all Get Adobe Acrobat Reader to view pdf files. ugs / geothermal resources Geothermal Resources Roosevelt Hot Springs, Beaver County. Nature of...

UK PubMed Central (United Kingdom)

Female mammals are particularly sensitive to changes in food availability. The mechanisms that affect sexual behavior and food intake are closely related to one another; chief among the mechanisms...Full Text Available

UK PubMed Central (United Kingdom)

Forty-one Spanish families with polycystic kidney disease 1 (PKD1) were studied for evidence of linkage disequilibrium between the disease locus and six closely linked markers. Four of these loci--three...Full Text Available

UK PubMed Central (United Kingdom)

Recent studies have suggested that intrauterine undernutrition is closely associated with the pathogenesis of diseases after birth. Perinatal undernutrition is known to disturb the development of reproductive...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Results are presented of analysis of the dust content of air and the resources for removing sludge at the mines of the Kuzbass during drilling of ascending shafts. A design is proposed for sludge removing devices with automatic opening and closing of the valve hinges.

UK PubMed Central (United Kingdom)

The efficacy of beta-lactam antibiotics and amikacin alone and in various combinations against Pseudomonas aeruginosa was studied in a rabbit model simulating a closed-space infection in a locally neutropenic...Full Text Available

UK PubMed Central (United Kingdom)

We have cloned and characterized the entire DNA polymerase gene and flanking regions from Kaposi's sarcoma-associated herpesvirus (KSHV) and two closely related macaque homologs of KSHV, retroperitoneal...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The theory and application of the optimal control of linear systems to stabilize or improve the system stability is well known. For an optimal linear regulator design, the arbitrariness involved in the parameters of the cost function always affects the final control law and the closed-loop system poles which decide the system dynamic characteristics. A new approach, 'The inverse problem approach' has been developed to overcome this difficulty. The system so designed will have preassigned closed-loop poles and the resulting closed-loop system performance can be ensured. In this paper the inverse problem approach for optimal regulator design is applied to the power system stabilizer (PSS) design for single-machine infinite-bus systems. The results show that, as far as the linearized model is concerned, systems designed by the inverse problem approach have better closed-loop performance ...

UK PubMed Central (United Kingdom)

Hundreds of thousands of people worldwide live or work in close proximity to steel mills. Integrated steel production generates chemical pollution containing compounds that can induce genetic damage...Full Text Available

UK PubMed Central (United Kingdom)

With the increase in multi-cultural families, Korea is seeing a rapid increase in immigrated housewives, who are closely related to food culture. However, studies for the diet of multi-cultural families,...Full Text Available

UK PubMed Central (United Kingdom)

Hepatocellular carcinoma (HCC) is a primary malignancy of the liver, which is closely related to hepatitis C and cirrhosis. The molecular mechanisms underlying the hepatocarcinogenesis induced by HCV...Full Text Available

Science.gov (United States)

...identity of a confidential source and, in the case of...lawful national security intelligence investigation, confidential...only by the confidential source, (v) Disclose investigative...exercise its authority to open to public observation...requires that the meeting be...

International Nuclear Information System (INIS)

The probabilistic risk assessment (PRA) of the General Electric BWR/6 Mark III standard plant has been used to assess the effect of proposed new quality assurance requirements on the off-site plant risk. This work was performed by General Electric Company under contract to the Electric Power Research Institute. First, the potential changes in the reliability of structures, systems and components were estimated. Then those changes that could affect the event tree and fault tree results were identified. Finally these changes were propagated through the probabilistic risk assessment fault trees and event trees to determine the effect upon off-site plant risk. The results show that applying quality assurance requirements, very nearly equal to those of 10CFR50, Appendix B (3), to nearly all nonsafety-related structures, systems, and components would have a negligible effect on off-site plant risk. In this paper, first the proposed new quality ...

Energy Technology Data Exchange (ETDEWEB)

The passive continental margin in the northern South China Sea is a weakly active area. It has been found to be favorable for large gas field development and also to be profitable for gas hydrate. The active faults, diapir structure, slump deposits, faults break of slopes, gas chimneys and sandstone of submarine fan, control the concentration of gas hydrate. Gas chimneys are widely distributed in the northern South China Sea. They supply the pathway for migration of deeper gas to gas hydrate stability zones especially in the basin of tectonic inactive zone. This paper discussed the geological structures of gas hydrate occurrence in gas fields and presented a detailed analysis of gas chimneys within the northern slope of the South China Sea. The paper described the geological setting of the Qiongdongnan Basin and provided information on the data description and processing. Two multichannel seismic (MCS) reflection profiles were used for the ...

Energy Technology Data Exchange (ETDEWEB)

Late plagiogranite bodies in the Semail ophiolite have been previously suggested to represent late stage fractionates within an episodic spreading center magma chamber or the roots of seamount chains. Field and lab observations suggest that these late silicic magma chambers represent zones of repeated injection by dikes of intermediate to mafic composition. Multiple generations of intrusion, partial resorption and reintrusion are preserved in the plagiogranite as 1) relict phantom xenoliths, 2) angular xenoliths with quartz-rich margins, 3) deformed fine-grained dikes with distinct chilled margins, and 4) planes of rectangular blocks with cuspate margins or ellipsoids of similar fine grained mafic materials. The blocks and ellipsoids are actually dismembered mafic dikes that chilled by intruding a cooler silicic liquid and were either thermally fractured or pinched out. All of the dikes are hydrothermally altered to assemblages including amph., qtz., epi., preh., and chl. and are ...

Energy Technology Data Exchange (ETDEWEB)

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 failure, and system analysis ...

Science.gov (United States)

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 ...

Energy Technology Data Exchange (ETDEWEB)

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 into four beds ...

International Nuclear Information System (INIS)

We studied the niobium re-entrant cavity utilized by the Australian group in the Niobe gravitational wave detector. Instead of using their non-contact re-entrant cavity, we plan to change it to a closed one to be used in the parametric transducers of the Brazilian Mario Schenberg detector. The performance of the transducer depends on some cavity parameters such as the electrical Q and the electrical coupling. We measured the resonant frequency and the loaded electrical Q as a function of the probe position in a closed niobium #approx#15 GHz cavity operating at 4.2 K.

Energy Technology Data Exchange (ETDEWEB)

A basic problem in gravitational physics is the resolution of spacetime singularities where general relativity breaks down. The simplest such singularities are conical singularities arising from orbifold identifications of flat space, and the most challenging are spacelike singularities inside black holes (and in cosmology). Topology changing processes also require evolution through classically singular spacetimes. I briefly review how a phase of closed string tachyon condensate replaces, and helps to resolve, basic singularities of each of these types. Finally I discuss some interesting features of singularities arising in the small volume limit of compact negatively curved spaces and the emerging zoology of spacelike singularities.

Energy Technology Data Exchange (ETDEWEB)

When nanometer scale holes (diameters of 50 to a few hundred nm) are imaged in a scanning electron microscope (SEM) at pressures in the 10{sup -5} to 10{sup -6} torr range, hydrocarbon deposits built up and result in the closing of holes within minutes of imaging. Additionally, electron beam deposition of material from a gas source allows the closing of holes with films of platinum or TEOS oxide. In an instrument equipped both with a focused ion beam (FIB), and an SEM, holes can be formed and then covered with a thin film to form nanopores with controlled openings, ranging down to only a few nanometers.

International Nuclear Information System (INIS)

We construct a phenomenological model which describes the dynamical chiral symmetry breaking (DCSB) of a QCD vacuum and reproduces meson spectra. Quark condensates, the pion decay constant, and meson spectra are well reproduced by the phenomenological interaction which consists of a linear confining potential, a Coulombic potential, and the close-quote t Hooft determinant interaction. In this model, the close-quote t Hooft determinant interaction plays an important role to not only the mass difference between the #eta# and #eta#"' mesons, but other meson masses through DCSB. copyright 1997 The American Physical Society.

Energy Technology Data Exchange (ETDEWEB)

We discuss the asymptotic dynamical evolution of spatially homogeneous brane-world cosmological models close to the initial singularity. We find that generically the cosmological singularity is isotropic in Bianchi type IX brane-world models and consequently these models do not exhibit Mixmaster or chaotic-like behaviour close to the initial singularity. We argue that this is typical of more general cosmological models in the brane-world scenario. In particular, we show that an isotropic singularity is a past-attractor in all orthogonal Bianchi models and is a local past-attractor in a class of inhomogeneous brane-world models. (letter to the editor)

International Nuclear Information System (INIS)

The control valve for a large steam turbine must be operated linearly to be run by an automatic control system in a power plant. It is, however, found that the flow increase is much greater for a given valve position change near the closed end of travel than it is near the open end. Accordingly, the desired linearization will be achieved if the valve is opened less near the closed end of travel and greater near the open end. The previous way for linearization was to utilize the cams, which is called the mechanical hydraulic control (MHC). The MHC was afterward improved by producing the nonlinear electric compensation to the nonlinear system of control valves, viz. the electro hydraulic control (EHC)

CERN Document Server

We consider light waves propagating clockwise and other light waves propagating counterclockwise around a closed path in a plane (theoretically with the help of stationary mirrors). The time difference between the two light propagating path orientations constitutes the Sagnac effect. The general relativistic expression for the Sagnac effect is discussed. It is shown that a gravitational wave incident to the light beams at an arbitrary angle will not induce a Sagnac effect so long as the wave length of the weak gravitational wave is long on the length scale of the closed light beam paths. The gravitational wave induced Sagnac effect is thereby null.

Energy Technology Data Exchange (ETDEWEB)

Closed string tachyons have long been somewhat mysterious. We note that there is often a regime in the classical moduli space in which one can systematically compute the effective action for such fields. In this regime, the tachyon is light, and cannot be integrated out. Instead, one must consider the combined dynamics of gravitons, moduli, tachyons and other light fields. We compute the action and find that the quartic term for the tachyon is positive in the field definition where the tachyon has no derivative coupling to the radion. We study the evolution of isotropic, homogeneous configurations and find that typically the system is driven to regions where the calculation is no longer under control. (author)

International Nuclear Information System (INIS)

Absolute, cascade-free excitation cross sections in an ion have been measured for the resonance "2S#->#"2P transition in Zn"+ using electron-energy-loss and merged electron-ion beams methods. Measurements were carried out at electron energies of below threshold to 6 times threshold. Comparisons are made with 2-, 5-, and 15-state close-coupling and distorted-wave theories. There is good agreement between experiment and the 15-state close-coupling cross sections over the energy range of the calculations.

International Nuclear Information System (INIS)

This report is the user's manual of seismic system reliability analysis code SECOM2 (Seismic Core Melt Frequency Evaluation Code Ver.2) developed at the Japan Atomic Energy Research Institute for systems reliability analysis, which is one of the tasks of seismic probabilistic safety assessment (PSA) of nuclear power plants (NPPs). The SECOM2 code has many functions such as: Calculation of component failure probabilities based on the response factor method, Extraction of minimal cut sets (MCSs), Calculation of conditional system failure probabilities for given seismic motion levels at the site of an NPP, Calculation of accident sequence frequencies and the core damage frequency (CDF) with use of the seismic hazard curve, Importance analysis using various indicators, Uncertainty analysis, Calculation of the CDF taking into account the effect of the correlations of responses and capacities of components, and Efficient sensitivity analysis by changing parameters on responses and capacities ...

Energy Technology Data Exchange (ETDEWEB)

Time contour expression of limited range phenomena on stack chart is examined for further improvement on the result of the ultimate interpretation in the seismic reflection survey. The policy is made clear from the beginning that local phenomena are to be discussed, and data prior CMP stacking is interpreted in detail. For this purpose, it is effective to make use of the time contour expression in the midpoint-offset plane simultaneously with the CMP and COP panels. For the review of data prior to CMP stacking, it is convenient to use the CMP (CDP) stacking chart in which the data is arranged methodically. In this chart, all the channels which are crude data prior to stacking are plotted on midpoint-offset coordinates, which plane is called the MOD (Midpoint Offset Domain) panel. Various panels can be chosen unrestrictedly, and their mutual relations can be easily grasped. When data points are given a time axis, they can be expressed in a time contour. Studies are conducted about the ...

Energy Technology Data Exchange (ETDEWEB)

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 operation of EDES; and verification of functions in actual earthquakes. It was concluded that when there is an emergency, the EDES functions as an online system using ...

Energy Technology Data Exchange (ETDEWEB)

As the surroundings of objects of oil exploration grow more complicated, seismic survey methods have turned 3-dimensional and, in this report, several models are examined using the 3-dimensional simulation technology. The result obtained by the conventional wave tracking method is different from actual wavefields, and is unrealistic. The difference method among the fullwave modelling methods demands an exorbitantly long computation time and high cost. A pseudospectral method has been developed which is superior to the difference method, and has been put to practical use thanks to the advent of parallel computers. It is found that a 3-dimensional survey is mandatory in describing faults. After examining the SEG/EAGE Salt model, it is learned that the salt is well-developed and that 3-dimensional depth migration is required for sub-salt exploration. It is also found through simulation of the EAGE/S Overthrust model, which is an elastic model, that no quality records ...