Search

Let T be a quasi-nonexpansive self-mapping of a closed convex subset of a uniformly convex Banach space satisfying Opial′s condition with I-T demiclosed with respect to zero. Then the sequence {xn}∞n=1 defined by xn+1=(1−αn)xn+αnTxn converges weakly to some fixed point of T. A similar result is obtained for continuous generalized nonexpansive mappings.

Primary water stress corrosion cracking (SCC) and an outside diameter SCC have occurred in the steam generator (SG) tubes of nuclear power plants in the republic of Korea and around the world. Although high corrosion resistant alloy 690 has been replacing the alloy 600 tubings, it is important to establish the repair criteria for the remaining degraded alloy 600 tubings to reassure regarding the reactors integrity, and still maintain the plugging ratio within the limits needed for its efficient operations. For assessment and management of the degradation, it is crucial to understand the initial leak behaviors and time dependent leak rate change from SCC flaws under a constant pressure. Stress corrosion cracked tube specimens were prepared at room temperature by the contact of sodium tetrathionate solution. The initial leak rate and time dependent leak rate were measured at different pressure ranges with time. Water pressure inside the tube was slowly increased in a step like manner with a designated holding time. The leak rate was calculated by dividing the amount of water by the time. A large open and long axial crack showed an increasing leak rate with time at a constant pressure, whereas small opened cracks did not show an increase in a time dependent leak rate. Under some pressures, the leak rate did not increase with the increase of pressure due to a tightness of circumferential cracks. Throughwall axial crack of 5 mm long may exhibit the leakage of action level 1 of the EPRI leakage guideline.Copyright © 2010 by ASME

High gradient magnetic separation of copper-oxide superconducting particles in a gas-fluidized bed has been studied experimentally. Particles over the size range 40-105 mu m exhibit classical behavior when fluidized with He gas at 77 K, whereas the more cohesive, smaller particles were difficult to fluidize. Separation experiments on a uniform mixture of tetragonal and orthorhombic phases have shown that 30 min of exposure to the field gradient is sufficient to equilibrate the superconductor concentration profile. In addition, the equilibrium separation data reveal that best separation is achieved at three times the minimum fluidization gas velocity (U/sub mf/). This is consistent with the behavior of fine powders where the interparticle frictional forces are minimized at 3 U/sub mf/. Observed results are discussed in terms of a collective effect of Meissner and interparticle frictional forces. >

Series representations for the average magnetization M are obtained from the known analytic solutions of the Bean model. It is found that as relatively high fields, M has the same functional dependence on H as J c . A power law behavior of M is found experimentally for YBCO powder samples, which indicates J c has a similar power law dependence.

Aims: This study aimed to isolate and identify potential polycyclic aromatic hydrocarbon (PAH)-degrading and/or metal-tolerant fungi from PAH-contaminated and metal-contaminated soils. Methods and Results: Pyrene-degrading fungi were isolated from contaminated soil and tested for metal (Cu, Zn and Pb) compound solubilization and metal accumulation. Three strains of Fusarium solani and one of Hypocrea lixii were able to degrade more than 60% of initial supplied pyrene (100 mg l−1) after 2 weeks. The isolates were grown on toxic metal (Cu, Pb and Zn)-containing media: all isolates accumulated Cu in their mycelia to values ranging from c. 5·9 to 10·4 mmol per kg dry weight biomass. The isolates were also able to accumulate Zn (c. 3·7–7·2 mmol per kg dry weight biomass) from zinc phosphate-amended media. None of the isolates accumulated Pb. Conclusions: These fungal isolates appear to show promise for use in bioremediation of pyrene or related xenobiotics and removal of copper and zinc from wastes contaminated singly or in combination with these substances. Significance and Impact of the Study: Microbial responses to mixed organic and inorganic pollution are seldom considered: this research highlights the abilities of certain fungal strains to interact with both xenobiotics and toxic metals and is relevant to other studies on natural attenuation and bioremediation of polluted sites.

Aims: For identification of members of the fungal order Eurotiales, an 18S rRNA gene-based oligonucleotide microarray was developed and optimized. Methods and Results: Eurotiales-specific probes covering most members of the Eurotiales as well as species-specific probes were designed and evaluated with three pure cultures (two fungi from the Eurotiales and one fungus from the Hypocreales). Nearly complete 18S rRNA genes of each reference culture were amplified and fluorescently labelled by random priming. Conclusions: Positive and negative hybridization results confirmed that the Eurotiales probes tested in this study could correctly identify members of the Eurotiales. The species-specific probes were also capable of species-level detection. Significance and Impact of the Study: These findings demonstrate the potential applications of a phylogenetic oligonucleotide microarray approach to characterizing fungal species and populations in environmental and other samples.

Simulated transportation of winter flounder, Pleuronectes americanus fingerlings was carried out to study the effects of lidocaine-hydrochloride on water parameters. Dissolved oxygen, ventilation rate, ammonia nitrogen and pH of control group, sham control group and lidocaine-hydrochloride treated groups of 5 ppm, 10 ppm, 20 ppm were tested at 1 h, 2 h, 3 h, 4 h and 5 h treatment duration. Lidocaine-hydrochloride treated groups, followed by sham control and control, were most effective in decreasing oxygen consumption and excretion of ammonia by fish. Lidocaine-hydrochloride dose-related decrease in oxygen consumption and excretion of ammonia were also established. pH declines in lidocaine-hydrochloride and sham control groups were more rapid compared to the control group. The results of this study reveal that lidocaine-hydrochloride is an effective sedative as a transportation mixture for winter flounder.

Fracture-mechanics crack growth tests were conducted on 25.4-mm-thick compact tension specimens of Types 304L and 316L Stainless steel and Incoloy 825 at 93{degrees}C and 1 atmosphere of pressure in simulated J-13 well water, which is representative of the groundwater at the Yucca Mountain site in Nevada that is proposed for a high-level nuclear waste repository. Crack growth rates were measured under various load conditions: load ratios of 0.2--1.0, frequencies of 2 {times} 10{sup {minus}4}{minus}1 Hz, rise times of 1--5000 s, and peak stress intensities of 25--40 MPa{center_dot}m{sup {1/2}}. The measured crack growthrates are bounded by the predicted rates from the current ASME Section 11 correlation for fatigue crack growth rates of austenitic stainless steel in air. Environmentally accelerated crack growth was not evident in any of the three materials under the test conditions investigated.

We investigate the caesium concentrations in soils in mountain areas near Gori nuclear power plant in Korea, focusing on the measurement limits to the 134Cs. In order to lower the minimum detectable amount (MDA) of activity for the 134Cs, we have used the ammonium molybdophosphate (AMP) precipitation method to get rid of the 40K existing in natural radioactivity, which reduces the MDA activity about 10 times smaller than those without the AMP precipitation method. The MDA results for the 134Cs were found to be in the range between 0.015 and 0.044 Bq/kg-dry weight. In order to diminish the background, we also have measured a part of the soil samples in Yangyang, a small town in the east coast of Korea. However, it turns out that in order to detect the 134Cs in the samples the MDA should be reduced to the level of mBq/kg-dry weight.

For a set of mobile sensor network, a precise localization is required in order to maximize the utilization of mobile sensor network. As well, mobile robots also need a precise localization mechanism for the same reason. In this paper, we showed a combination of various localization mechanisms. Localization can be classified in three big categories: long distance localization with low accuracy, medium distance localization with medium accuracy, and short distance localization with high accuracy. In order to present localization methods, traditional map building technologies such as grid maps or topological maps can be used. We implemented mobile sensor vehicles and composed mobile sensor network with them. Each mobile sensor vehicles act as a mobile sensor node with the facilities such as autonomous driving, obstacle detection and avoidance, map building, communication via wireless network, image processing and extensibility of multiple heterogeneous sensors. For localization, each mobile sensor vehicle has abilities of the location awareness by mobility trajectory based localization, RSSI based localization and computer vision based localization. With this set of mobile sensor network, we have the possibility to demonstrate various localization mechanisms and their effectiveness. In this paper, the preliminary result of sensor mobility trail based localization and RSSI based localization will be presented.

Background Members of the established public health systems and medical community must understand that, in medical surge events, members of the dental profession and other non-traditional disaster health care personnel are an additional source of assistance in response activities. Methods The authors relied on hands-on experience, expert consultations, literature reviews and Web searches to identify disaster response training programs appropriate for members of the dental profession and other health care personnel. Results The authors identified multiple governmental and professional disaster training programs. Conclusions Five key national-level programs address the training and organization of health care professionals to support a large-scale disaster program. Because of their training and skills, dental professionals would be valuable additions to these programs and could make significant contributions if natural disasters and/or terrorist events were to occur.

Effects of Pb on passivity of Alloy 600 surface were investigated in mild acidic aqueous solutions at 90°C using polarization, electrochemical impedance spectroscopy (EIS), Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS). The results indicate that Alloy 600 surface consists of an inner oxide layer and outer hydroxide layer, containing Cr3+ and Ni2+. Pb is incorporated into the surface film and increases the electronic conductivity of Cr oxide in the surface film. Oxidation of Ni is inhibited by the presence of Pb.

This research is carried out to improve productivity of robot welding shop of subassembly line. This is a part of full automation of robot welding shop and is realized as the 3D simulator for robot welding. UML and IDEF methods are used to analyze system to be model and the analysis is to be foundation of simulator. Robot welding shop is a semimechanized shop. So this shop has possibility to be mechanization and it can be simulated precisely than other shop operated a worker. The simulator implements the process of robot welding shop, but there are some problems that are hard to be solved by only the simulation tool supported 3D simulation, IGRIP. These are determination of working sequence and work area in this research. And these two problems need other optimum techniques. The concept of TSP and genetic algorithm are used to find shortest work sequence. This simulator presents result of optimum plans and estimates cycle time for specific amount of work be done.

IP multicast is a technique that can transmit one copy of data traffic to multiple receivers at one time. Because it can greatly save the network bandwidth consumption and many applications are inherently multicast-based, it has been a research focus since the idea was proposed. However, because of many reasons, such as management, security, inter-domain routing, etc, it has not been widely deployed. Recently, many researchers have put their research focus on overlay multicast. In overlay multicast, the data replication, multicast routing, group management and other functions are all achieved at application layer. Because it does not require any change to the current Internet infrastructure, it can be easily deployed. Since the idea was proposed, many overlay multicast ideas have been proposed. In this paper, we propose a method for reliable data transfer on overlay multicast. It applies TCP at transfer-layer and local data buffering at application-layer. This paper explains the advantages and disadvantage of using TCP for reliable data transfer on overlay multicast, then, describes the operation of our method and induces an optimal buffer size in dynamic nodes based overlay multicast. Finally, we check the effect of data buffering with experiments on several models.

The simultaneous estimation of seafloor and water column information from a combination of bathymetric lidar and passive spectral data represents an evolution in shallow water mapping. Here, we demonstrate recent progress on the use of SHOALS waveforms and depths to constrain inversion algorithms for passive spectral data. We use these inversions within a data fusion paradigm to achieve 3-dimensional benthic mapping, while simultaneously describing horizontal spatial variations in water column optical parameters.

To meet requirements in mobile communications and microwave integrated circuits, miniaturization of the passive components that many of these systems require is of key importance. In this paper, spiral and solenoid-type RF micro-inductors and micro-transformers with 3-D structures have been newly designed, fabricated, and characterized on GaAs and silicon substrates by using electroplating techniques, multi-layer thick photoresist, and low temperature processes. The applied processing techniques are also compatible with MMIC, RFIC, and CMOS circuitry fabrication due to their simple fabrication steps. In particular, relationship of performance characteristics and geometry of spiral and solenoid micro-inductors and micro-transformers is deeply investigated such as windings, cross-sectional area of core, spacing between windings, and turn ratio. The microwave characteristics of the fabricated micro- inductors and micro-transformers have been measured in the frequency range of 0.5 to 40 GHz for RF applications.

In this paper we prove the existence of mild and strong solutions of an integrodifferential equation of Sobolev type with nonlocal condition. The results are obtained by using uniformly continuous semigroups and the Schauder fixed point theorem.

An experimental investigation has been conducted to reduce NO/sub x/ from natural gas combustion flue gases by means of corona discharge activated ammonia/methane radical injection methods. The multi-hole type corona radical injectors are used in the present investigation. Experiments are conducted for the simulated natural gas combustion flue gas (N/sub 2/:O/sub 2/:CO/sub 2/:NO=83.96:8:8:0.04) flow rate from 1 to 200 l/min., activation voltage (DC or pulse) from 0 to 40 kV and Ar-ammoniathe or Ar-methane mixture gases flow rate from 0 to 200 ml/min. The results show that the NO/sub x/ reduction increases with increasing activation voltage and nonmonotonically depends on ammonia/methane stoichiometry.

A new bandpass filter that is composed of two stage microstrip ring resonators with the center frequency of 5.775 GHz and the bandwidth of 100 MHz has been presented in this paper. For the suppression of unnecessary harmonics, lowpass filters are integrated into a microstrip ring resonator. Harmonic suppression ratios of about 35 dB are obtained. Also, a varactor-tuned microstrip ring bandpass filter with harmonic suppression is studied. Insertion loss of 6 dB and tuning bandwidth of 450 MHz are obtained for this circuit.

This paper illustrates the use of an “equivalent rectangular crack” approach to predict leak rates through laboratory generated stress corrosion cracks. A comparison between predicted and observed test data on rupture and leak rate from laboratory generated stress corrosion cracks are provided. Specimen flaws were sized by post-test fractography in addition to pre-test advanced eddy current technique. The test failure pressures and leak rates are shown to be closer to those predicted on the basis of fractography than on NDE. However, the predictions based on NDE results are encouraging, particularly because they have the potential to determine a more detailed geometry of ligamented cracks from which more accurate predictions of failure pressure and leak rate can be made in the future.

This paper discusses round-robin exercises using the NRC steam generator (SG) mock-up at Argonne National Laboratory to assess inspection reliability. The purpose of the round robins was to assess the current reliability of SG tubing inservice inspection, determine the probability of detection (POD) as function of flaw size or severity, and assess the capability for sizing of flaws. For the round robin and subsequent evaluation completed in 2001, eleven teams participated. Bobbin and rotating coil mock-up data collected by qualified industry personnel were evaluated. The mock-up contains hundreds of cracks and simulations of artifacts such as corrosion deposits and tube support plates that make detection and characterization of cracks more difficult in operating steam generators than in most laboratory situations. An expert Task Group from industry, Argonne National Laboratory, and the NRC have reviewed the signals from the laboratory-grown cracks used in the mock-up to ensure that they provide reasonable simulations of those obtained in the field. The mock-up contains 400 tube openings. Each tube contains nine 22.2-mm (7/8-in.) diameter, 30.5-cm (1-ft) long, Alloy 600 test sections. The flaws are located in the tube sheet near the roll transition zone (RTZ), in the tube support plate (TSP), and in the freespan. The flaws are primarily intergranular stress corrosion cracks (axial and circumferential, ID and OD) though intergranular attack (IGA) wear and fatigue cracks are also present, as well as cracks in dents. In addition to the simulated tube sheet and TSP the mock-up has simulated sludge and magnetite deposits. A multiparameter eddy current algorithm, validated for mock-up flaws, provided a detailed isometric plot for every flaw and was used to establish the reference state of defects in the mock-up. The detection results for the 11 teams were used to develop POD curves as a function of maximum depth, voltage and the parameter mp , for the various types of flaws. The POD curves were represented as linear logistic curves, and the curve parameters were determined by the method of Maximum Likelihood. The effect of both statistical uncertainties inherent in sampling from distributions and the uncertainties due to errors in the estimates of maximum depth and mp was investigated. The 95% one-sided confidence limits (OSL), which include errors in maximum depth estimates, are presented along with the POD curves. For the second round robin a reconfigured mock-up is being used to evaluate the effectiveness of eddy current array probes. The primary emphasis is on the X-Probe. Progress with the X-Probe round robin is discussed in this paper.Copyright © 2002 by ASME

Background/Aims: Occult HBV infection can persist following HBsAg loss and be transmitted, but the virological features are not well defined. Methods: Here we investigated 25 Korean patients who lost HBsAg during follow up, either spontaneously or subsequent to therapy. Results: Whereas subtype adr (genotype C) was found in 96% of HBsAg positive patients, 75 % of patients who lost HBsAg spontaneously were seemed to be infected with the ayw subtype with sequence similar to genotype D. Mutations in the major hydrophilic region (MHR) of HBsAg were found in 7 patients who lost HBsAg spontaneously. The mutations include T123S, M125I/N, C139R, D144E, V177A, L192F, and W196L, some of which have not been reported before. Functional analysis via transfection experiments indicate that the C139R and D144E mutations drastically reduced HBsAg antigenicity, while the Y225del mutation found in one interferon-treated patient impaired HBsAg secretion. Conclusions: Lack of detectable HBsAg in patient serum could be explained by low level of ccc DNA in liver tissue, low antigenicity of the surface protein, or its secretion defect. (Clin Mol Hepatol 2014;20:251 260)

Background/Aims This study assessed the antiviral efficacy and safety of tenofovir disoproxil fumarate (TDF) for up to 12 months in Korean treatment-naïve chronic hepatitis B (CHB) patients. Methods A total of 411 treatment-naïve CHB patients who had been treated with TDF for at least 3 months (median 5.6) were consecutively enrolled. Clinical, biochemical, virological parameters and treatment adherence were routinely assessed every 3 months. Results The median age was 51.3 years, 63.0% of the patients were male, 49.6% were HBeAg (+), and 210 patients had liver cirrhosis. The median baseline HBV DNA was 5.98 (SD 1.68) log10 IU/mL. Among the patients completing week 48, 83.3% had a complete virologic response (CVR