In 2010 the ITER Organization (IO) proposed to eliminate the beryllium armour on the plasma-facing surface of the diagnostic port plugs and instead to use bare stainless steel (SS), simplifying the ...design and providing significant cost reduction. Transport simulations at the IO confirmed that charge-exchange sputtering of the SS surfaces would not affect burning plasma operation through core impurity contamination, but a second key issue is the potential melt damage/material loss inflicted by the intense photon radiation flashes expected at the thermal quench of disruptions mitigated by massive gas injection. This paper addresses this second issue through a combination of ITER relevant experimental heat load tests and qualitative theoretical arguments of melt layer stability. It demonstrates that SS can be employed as material for the port plug plasma-facing surface and this has now been adopted into the ITER baseline.
A concept for a shaped first wall for ITER is presented. While keeping most features of the 2004 FDR wall (modules segmentation, plasma facing components technologies, plasma facing material), this ...concept provides protection of the lateral faces of the first wall panels against the intense parallel heat flux coming from the plasma. Excessive beryllium temperatures at the panel edges are avoided during regular operation. The intense heat flux at the top of the vessel is accounted for and protection is provided against the shine thru heat flux. Start-up and ramp down using the wall as a limiter is possible for up to 7.5
MW, both inboard and outboard. This is rendered possible by the use of 5
MW/m
2 technology panels for 40% of the panels.
Nuclear analysis of the ITER full-tungsten divertor Villari, R.; Barabash, V.; Escourbiac, F. ...
Fusion engineering and design,
October 2013, 2013-10-00, 20131001, Letnik:
88, Številka:
9-10
Journal Article
Recenzirano
•3D nuclear analysis of the last design of ITER full-W divertor.•Calculate nuclear heating, damage and he-production in divertor components.•Evaluate impact on design and maintenance of the system.
...This paper presents the nuclear analysis performed for the ITER full-tungsten divertor using the MCNP-5 Monte Carlo Code in a 3-D geometry. A detailed model of the geometry of the divertor based on the last design specifications has been integrated into the latest ITER MCNP model. Nuclear heating, damage and helium production have been calculated. The presented results are consistent with recent analysis performed with ATTILA code and with the previous ones with MCNP. The shielding capabilities of the last design are reduced in comparison with the design of 2004 but a negligible impact is expected. The reweldability of radial pipes of the cassette body (CB) is not a concern even assuming irradiation during the whole ITER lifetime. The reweldability of pipes for the refurbishment of the CB with new plasma facing components depends on maintenance scenario. It is not expected that last 2012 divertor design leads to an appreciable increase of the nuclear loads on vacuum vessel and toroidal field coils, since the relative contribution of the divertor region remains low.
Abstract This study was designed to determine if the efficiency of in-vitro maturation (IVM) in women with normal ovaries can be improved by gonadotrophin administration. 400 women were randomly ...allocated in four groups: group A, non-primed cycles; group B, human chorionic gonadotrophin (HCG)-primed cycles; group C, FSH-primed cycles; and group D, FSH- plus HCG-primed cycles. There were significant differences in the IVM rate among the groups. In groups where HCG was used, the overall maturation rate was higher (57.9% in group B and 77.4% in group D; 48.4% in group A and 50.8% in group C) and the percentage of total available metaphase II-stage oocytes was higher (60.4% in group B and 82.1% in group D; 48.4% in group A and 50.8% in group C). The overall clinical pregnancy rate per transfer (CPR) was 18.3% and the implantation rate (IR) was 10.6%. There was a difference in CPR among the groups: group D (29.9%) versus group A (15.3%), P = 0.023; group D versus group B (7.6%), P < 0.0001; group D versus group C (17.3%), P = 0.046. The results of this study are clearly in favour of FSH plus HCG priming. FSH priming and HCG priming alone showed no significant effects on clinical outcome.
The limited resources of petroleum-based lubricants and increased environmental contamination, that they produce, lead to increased demand for bio-lubricants. Due to several factors such as ...biodegradability, good lubricating properties and low production costs, the plant oils represent a good alternative as reference to replace the petroleum-based oils. Obviously, the need to ensure the use of vegetable oils as a source of food makes non-edible vegetable oils a formidable source for plant oil lubricants. Thus, the toxicity of Jatropha Curcas L. oil makes it a very attractive and alternative lubricant source. Therefore, the aim of this work is to investigate on tribological performance of Jatropha Curcas L. oil in the lubricating contact pair AISI 52100 steel sliding against X210Cr12 steel. The experimental tests were carried out using ball-on-flat reciprocatory tribometer for several frequencies and with normal load of 12N. The Jatropha Curcas L. oil was analyzed for its chemical and physical properties such as viscosity, density and flash point. The results were interpreted on the basis of the evolution of the friction coefficient. The evolution of the friction coefficient was monitored for 40min in all tests. The results show that the friction coefficient decreases with the increase of the frequency, and the final value stays in the range of 0.04-0.122.
This paper is concerned with investigation of an erosion of the ITER-like divertor plasma facing components under plasma heat loads expected during the Type I ELMs in ITER. These experiments were ...carried out on plasma accelerator QSPA at the SRC RF TRINITI under EU/RF collaboration. Targets were exposed by series repeated plasma pulses with heat loads in a range of 0.5–1.5MJ/m2 and pulse duration 0.5ms. Erosion of CFC macrobrushes was determined mainly by sublimation of PAN-fibres that was less than 2.5μm per pulse. The CFC erosion was negligible at the energy density less than 0.5MJ/m2 and was increased to the average value 0.3μm per pulse at 1.5MJ/m2. The pure tungsten macrobrushes erosion was small in the energy range of 0.5–1.3MJ/m2. The sharp growth of tungsten erosion and the intense droplet ejection were observed at the energy density of 1.5MJ/m2.
•Mechanical properties of stress-relieved and recrystallized tungsten.•FEM of ITER tungsten divertor monoblock under high heat loads.•Modification of tungsten properties under high heat loads due to ...recrystallization.
In the full-tungsten divertor qualification program at ITER Organization, macro-cracks, so called self-castellation were found in a fraction of tungsten monoblocks during cyclic high heat flux loading at 20MW/m2. The number of monoblocks with macro-cracks varied with the tungsten products used as armour material. In order to understand correlation between the macro-crack appearance and W properties, an activity to characterize W monoblock materials was launched at the IO. The outcome highlighted that the higher the recrystallization resistance, the lower the number of cracks detected during high heat flux tests. Thermo-mechanical finite element modelling demonstrated that the maximum surface temperature ranges from 1800 °C to 2200 °C and in this range recrystallization of tungsten occurred. Furthermore, it indicated that loss of strength due to recrystallization is responsible for the development of macro-cracks in the tungsten monoblock.
Community support for license plate recognition M. Merola, Linda; Lum, Cynthia; Cave, Breanne ...
Policing : an international journal of police strategies & management,
01/2014, Letnik:
37, Številka:
1
Journal Article
Recenzirano
Purpose
– Although the use of license plate recognition (LPR) technology by police is becoming increasingly common, no empirical studies have examined the legal or legitimacy implications of LPR. LPR ...may be used for a variety of purposes, ranging from relatively routine checks of stolen vehicles to more complex surveillance functions. The purpose of this paper is to develop a “continuum of LPR uses” that provides a framework for understanding the potential legal and legitimacy issues related to LPR. The paper then analyzes results from the first random-sample community survey on the topic.
Design/methodology/approach
– Random-sample survey (n=457).
Findings
– The paper finds substantial support for many LPR uses, although the public also appears to know little about the technology. The survey also reveals that the public does not regard the uses of LPR as equivalent, but rather support is qualified depending upon the use at issue.
Originality/value
– Previous research has not systematically categorized the wide variety of LPR uses, an oversight which has sometimes led to implicit consideration of these functions as if they are equivalent in their costs and benefits. To assist agencies concerned with community responses to LPR use, the paper points to a number of factors tending to decrease support for LPR, namely, the extent to which a use involves purposes unrelated to vehicle enforcement, the extent to which a function involves prolonged storage of individuals’ travel data, and the extent to which a use is perceived as impacting “average” members of the community.
The design of the ITER first wall panels Mitteau, R.; Calcagno, B.; Chappuis, P. ...
Fusion engineering and design,
10/2013, Letnik:
88, Številka:
6-8
Journal Article
Recenzirano
Odprti dostop
•The ITER blanket is in the final stage of design completion.•Issues raised about the blanket heat loads and remote handling strategy are addressed, while integrating the in-vessel coils.•Key design ...justifications are presented, followed by a summary of the current status of the manufacturing plan and R&D activities.
The ITER blanket is in the final stage of design completion. The issues raised during the 2007 ITER design review about the first wall (FW) heat loads and remote handling strategy have been addressed, while integrating the recently confirmed in-vessel coils. This paper focuses on the FW design, which is nearing completion. Key design justifications are presented, followed by a summary of the current status of the manufacturing plan and R&D activities.
The paper concerns experimental investigations of plasma facing components erosion under the plasma heat loads expected in ITER divertor during transient events such as the Type I Edge-Localized ...Modes and the disruptions. The experiments were carried out at the TRINITI plasma gun QSPA-T. The carbon fiber composite and tungsten macrobrush targets designed for ITER were exposed to multiple plasma pulses of duration 0.5ms and deposited energy in the range of 0.2–2.5MJ/m2. Between some of the pulses the eroded surface was analyzed with profilometric measurements and electron microscopy. The CFC erosion is determined mainly by damages to the PAN-fibers. While the energy increases from 0.2 to 2.4MJ/m2 the removed layer of PAN-fibers area increases from 0.01 to 10μm per pulse. The erosion of tungsten (pure and lanthanum oxide-doped tungsten) is shown to be determined mainly by crack formation, melt layer movement and droplets ejection.
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