Several designs of Nb 3 Sn Cable-In-Conduit Conductors (CICCs) have been proposed so far for high-performance tokamak magnets. The Nb 3 Sn strands composing the conductors are subjected to mechanical ...stresses of electromagnetic (EM) and thermal origin, inducing local deformations and affecting the strands critical current carrying capability. In the last ten years a numerical tool based on a finite element (FE) code has been developed to simulate the mechanical behavior of the CICCs subjected to operating loads. The main goal of this tool is to predict the electro-mechanical performance of the conductor in operation as a function of the design parameters such as the void fraction, the twist pitches and the conductor shape. In this work, a detailed model of a full-cable ITER TF CICC is presented. This model proves useful for a deeper understanding of the mechanical phenomena occurring among the sub-cables during the conductor operation. Moreover, the numerical modelling of different conductors from the ITER, DTT and JT60 projects is also presented to highlight the versatility of the code.
The Isotope and Muon Production using Advanced-Cyclotron and Target Technology Project (IMPACT) foresees the introduction of two new target stations and three new beamlines: one for radionuclide ...production and two for surface muon production. The latter forms the project, High-Intensity Muon Beams (HIMB), which plans to increase the muon rate from the current world record of 10 8 µ + /s up to 10 10 µ + /s. This work presents an overview of the future HIMB beamlines focusing on the magnet designs that have been developed to ensure increased muon rate production and transmission. Specific radiation-hard resistive coils, based on mineral insulation, are required in this case due to the proximity to the target station. A high muon capture and transmission efficiency requires solenoid-like magnets, as well as dipole magnets and crossed-field separators to select the desired particles, while suppressing unwanted background particles. The radiation-hard capture solenoid plays the most important role in the whole beamline since it must provide a high capture efficiency. Beam optics studies provided the on-axis field profile necessary for optimizing the size and shape of the capture solenoid. Therefore, the article will also elucidate on these solenoid design strategies for achieving the desired capture efficiency.
Several designs of Nb 3 Sn Cable-In-Conduit Conductors (CICCs) have been proposed so far for high-performance tokamak magnets. The Nb 3 Sn strands composing the conductors are subjected to mechanical ...stresses of electromagnetic (EM) and thermal origin, inducing local deformations and affecting the strands critical current carrying capability. In the last ten years a numerical tool based on a finite element (FE) code has been developed to simulate the mechanical behavior of the CICCs subjected to operating loads. The main goal of this tool is to predict the electro-mechanical performance of the conductor in operation as a function of the design parameters such as the void fraction, the twist pitches and the conductor shape. In this work, a detailed model of a full-cable ITER TF CICC is presented. This model proves useful for a deeper understanding of the mechanical phenomena occurring among the sub-cables during the conductor operation. Moreover, the numerical modelling of different conductors from the ITER, DTT and JT60 projects is also presented to highlight the versatility of the code.
The electrical performance degradation of Nb3Sn cables in the Cable-in-Conduit Conductors CICC has been well documented in literature. The Nb3Sn composite strands exhibit a critical cur-rent density ...that strongly depends on the strain state of the su-perconducting filaments. During a fusion magnet operation, the conductors are submitted to several electromagnetic and thermal cycles affecting the Nb3Sn mechanical state and consequently the capacity of the conductors to transport current. Different studies based on both a macroscopic and microscopic approaches have been performed so far to identify the mechanisms determining the conductors' behavior. Nevertheless, no theory permitting to predict the electrical performance of cyclically loaded conductors has been developed yet. Therefore, a solid electromechanical mod-el able to tackle the analysis of CICC for fusion cables when they undergo thousands of cyclic loadings would be very useful. In this paper an advanced mechanical model to study the me-chanical behavior of ITER TF CICC based on an improved ver-sion of the MULTIFIL finite element code is presented. A correc-tion is introduced to solve the problem of the large impact of the boundary conditions in the simulation of the thermal loading, en-countered in a previous work. A novel methodology to identify the value of thermal strain to be applied in cool-down simulations has also been developed. The model was adapted to take into ac-count the Lorentz force cumulative effect of the other petals on the one under analysis. An assessment of the electromagnetic behavior based on the mechanical analysis is also presented.
In 1994-1996 the Sun and the Earth passed through the equatorial plane of Saturn and therefore through the orbital planes of its main satellites. During this period, phenomena involving seven of ...these satellites were observed. Light curves of eclipses by Saturn and of mutual eclipses and occultations were recorded by the observers of the international campaign PHESAT95 organized by the Institut de mécanique céleste, Paris, France. Herein, we report 66 observations of 43 mutual events from 16 sites. For each observation, information is given about the telescope, the receptor, the site and the observational conditions. This paper gathers together all these data and gives a first estimate of the precision providing accurate astrometric data useful for the development of dynamical models.
This communication assesses the use of a portable near infrared (NIR) instrument to measure quantitative (fatty acid profile) properties and qualitative ('Premium' and 'Non-premium') categories of ...individual Iberian pork carcasses at the slaughterhouse. Acorn-fed Iberian pigs have more unsaturated fats than pigs fed conventional compound feed. Recent advances in miniaturisation have led to a number of handheld NIR devices being developed, allowing processing decisions to be made earlier, significantly reducing time and costs. The most common methods used for assessing quality and authenticity of Iberian hams are analysis of the fatty acid composition of subcutaneous fat using gas chromatography and DNA analysis. In this study, NIR calibrations for fatty acids and classification as premium or non-premium ham, based on carcass fat measured in situ, were developed using a portable NIR spectrometer. The accuracy of the quantitative equations was evaluated through the standard error of cross validation or standard error of prediction of 0.84 for palmitic acid (C16:0), 0.94 for stearic acid (C18:0), 1.47 for oleic acid (C18:1) and 0.58 for linoleic acid (C18:2). Qualitative calibrations provided acceptable results, with up to 98% of samples (n = 234) correctly classified with probabilities ⩾0.9. Results indicated a portable NIR instrument has the potential to be used to measure quality and authenticity of Iberian pork carcasses.
Forest degradation is a severe threat to the provision of ecosystem services, such as timber production, biodiversity and hydrogeological protection. Forest abandonment is one of the main causes of ...forest degradation in Mediterranean areas where the low value-added of forest activities affects economic sustainability. This issue requires urgent restoration actions which must be supported by cost–benefit analysis that comprises all forestry activities that generate income, including the recreational ones. In effect, while the impact of forest management systems on timber production is well studied, the impact of recreational values is not. The present article intends to demonstrate that different forms of forest management result in a differing willingness to pay (WTP) for maintaining the recreational use of forests. We collected 248 questionnaires from respondents who confirmed their WTP for the maintenance of the recreational function of forests under three management systems: coppice, active conversion to high forest, and the natural evolution of forests. Moreover, we tested the influence of certain socio-demographic variables on individual WTP. Users elicited a high preference for conversion to high forest, while natural evolution was the least preferred management system. Moreover, males and users with higher levels of education had a greater WTP for conversion to the high forest approach.
Due to several ecosystem services provided to the community, the multifunctional management of forests has acquired an important role over the years.
The current Sustainable Forest Management (SFM) ...guidelines are based on planning programmes which are able to achieve targets from socio-economic and environmental points of view.
In this paper, SFM indicators have been studied and compared to estimate the sustainability of three coppice options, from both an economic and a socio-environmental viewpoint. Each indicator was studied in relationship to the treatment and to the considered areas. The results of the statistical analysis show differences among treatments, and the possible correlations between the indicators. Moreover, by using principal component analysis (PCA), the correlations between the indicators were analysed, while the ways in which they influenced the examined sites were also considered. In particular, specific homogeneous clusters separating the observed sites were observed based on treatment and geographical gradient. Overall, the set of indicators used has proven to be effective when carrying out an evaluation of the existing types of forest management based on the analysis of three fundamental aspects of the SFM.
•This study analyze a set of socio-economic indicators related to different forest management options.•Using PCA, the correlations between the indicators were analysed.•Results show differences among treatments, and the possible correlations between the indicators.•The indicators used has proven to be effective when carrying out an evaluation of the existing types of forest management.
Food safety related incidents have increased consumers’ concern about food safety and quality and led to a distrust in the Chinese food market. This paper investigates how sociodemographic variables ...affect willingness to pay (WTP) both for safer and higher quality food by identify a specific user profile. Data were collected through a consumer survey conducted in Hangzhou, Zhejiang Province, administrating 1000 questionnaires, 757 of which resulted valid. Data showed that level of education, income, being married and the place of purchase significantly influences the WTP while the ages does not affect it. WTP is elicited by using a payment card method, and its estimation is performed with interval data regression model. Results also indicates that “food quality” and “food safety” have the same impact level on the WTP, indicating certain confusion about their significance. Other study results and implication on informative and educative policies are discussed.
•Paper analyse the perception that a sample of people has of food safety and quality.•Over 700 questionnaires distributed in China (Hangzhou, Zhejiang Province).•We asked WTPs more than standard price for safer and higher quality rice.•In order to test how variables explored affect WTPs, interval data regression was performed.
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•Consolidated and novel indicators of coppice forest sustainability used at stand scale.•Half of the indicators showed significant differences among management options.•Carbon cycle, ...forest health and socio-economic indicators were highly discriminative.•A subset of indicators was selected, useful to support managers and decision makers.
Although coppice forests represent a significant part of the European forest area, especially across southern Countries, they received little attention within the Sustainable Forest Management (SFM) processes and scenarios, whose guidelines have been mainly designed to high forests and national scale. In order to obtain “tailored” information on the degree of sustainability of coppices on the scale of the stand, we evaluated (i) whether the main coppice management options result in different responses of the SFM indicators, and (ii) the degree to which the considered SFM indicators were appropriate in their application at stand level. The study considered three different management options (Traditional Coppice TC, coppice under Natural Evolution NE, and coppice under Conversion to high forest by means of periodical thinning CO). In each of the 43 plots considered in the study, which covered three different European Forest Types, we applied a set of eighteen “consolidated” SFM indicators, covering all the six SFM Criteria (FOREST EUROPE, 2020) and, additionally, tested other sixteen novel indicators shaped for agamic forests and/or applicable at stand level. Results confirmed that several consolidated indicators related to resources status (Growing stock and Carbon stock), health (Defoliation and Forest damage), and socio-economic functions (Net revenue, Energy and Accessibility) were highly appropriate for evaluating the sustainability of coppice at stand level. In addition, some novel indicators related to resources status (Total above ground tree biomass), health (Stand growth) and protective functions (Overstorey cover and Understorey cover) proved to be highly appropriate and able to support the information obtained by the consolidated ones. As a consequence, a subset of consolidated SFM indicators, complemented with the most appropriate novel ones, may represent a valid option to support the evaluation of coppice sustainability at stand level. An integrated analysis of the SFM indicators showed that NE and CO display significant higher environmental performances as compared with TC. In addition, CO has positive effects also on socio-economic issues, while TC -which is an important cultural heritage and a silvicultural option that may help to keep local communities engaged in forestry – combines high wood harvesting rates with dense understory cover. Overall, each of the three management options showed specific sustainability values; as a consequence, their coexistence at a local scale and in accordance with the specific environmental conditions and the social-economic context, is greatly recommended since it may fulfill a wider array of sustainability issues.
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