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Reception studies is an important trend in contemporary film studies, especially in the current situation, which is characterised by media convergence and audience differentiation. One area of such...

Throughout the 20th century, cinema has played, and, to some extent, continues to play a key role in shaping the social imagination and anthropology of modern human. Nevertheless, as a review of English scholarly literature shows, cinema, unlike art and music, remains a marginal subject of analysis for sociologists. The article attempts to consider the state of sociological reflection on cinema in the context of the cultural turn in sociology in both the international and national contexts. By reconstructing the history of the interaction between sociology, film studies, and cultural studies, the author not only proves the scar-city of interest among sociologists in the analysis of cinema, but also discusses the ways by which socio-logical perspectives were involved in film research at the turn of the 20th–21st centuries, and the potential of the latter for the study of social imagination. A survey of communities of Soviet sci-fi cinema fans demonstrates one possible way of developing of the sociologically oriented program of cinema studies.

The coupling currents loss for fusion conductors is frequently assessed applying a sinusoidal field sweep of fixed, small amplitude and variable frequency. From the initial slope of the loss curve, the coupling loss time constant is derived and applied in the loss calculation over the whole range of field transient. In this work, the traditional AC loss assessment is compared to an alternative experimental assessment made on a trapezoidal field change, which mimics the actual field change rate in the central solenoid of tokamaks during the plasma start-up. The comparative loss assessment is made using the test results of the Nb3Sn react&wind conductor developed at SPC and an ITER TF conductor. The proposed AC loss assessment allows an accurate estimate of the deposited energy during plasma start-up for the Central Solenoid.

The knowledge of the strain distribution of Nb3Sn filaments in a CICC cross-section is a key parameter in understanding the performance and its evolution when the cable undergoes electromagnetic cyclic loading. This work focuses on the Wind and React (WR1) rectangular CICC sample designed by ENEA for the European DEMO project, that has exhibited a current sharing temperature (Tcs) above 6.9 K at 13 T and 81.7 kA, during its qualification tests in the EDIPO facility at the Swiss Plasma Center. Compared to the critical current tests on the constituting wires, the observed CICC performance corresponded to an effective strain value of −0.55%. This work aims to interpret this result on the basis of the analysis of the strain distribution inside the cable itself. Susceptibility versus temperature of WR1 constituting free standing strands has been measured after etching of the stabilizing copper, and it has been compared with the susceptibility measured on the cable during the test campaign in EDIPO. A well-known and already assessed method has been used, starting from susceptibility measurements, to compute the Tc distribution in the cable cross-section and, subsequently, to infer from that the thermal strain distribution. The obtained results give an indication that the strain distribution in WR1 cable is narrow, compared to the strain distribution calculated with the same method for most ITER TF and CS conductors.

A Nb3Sn based, React&Wind flat cable, named RW2, was developed in the past three years at the Swiss Plasma Center in the scope of the EUROfusion conceptual studies for DEMO. The test results presented earlier proved an excellent DC performance, but large eddy currents loss in the segregated copper. Here we present the results of a prototype conductor assembled in late 2019 from an older section of RW2 cable and a novel stabilizer, made by two Rutherford cables of thick, high RRR copper wires extruded with a cladding of high resistivity CuNi alloy. The results of the test in SULTAN of the new prototype are discussed in terms of DC and AC loss performance. The AC loss is measured in both orientations, for sinusoidal and trapezoidal field pulses. The test is carried out at both 4.5 K and 20 K operating temperature, allowing separating the contribution of the eddy currents in the segregated copper from the other sources of ac loss, hysteresis and coupling loss. The goal of reducing the eddy currents to a level comparable to the coupling current loss is achieved with the cabled stabilizer, which is now retained as baseline for the React&Wind DEMO conductor.

In the frame of the conceptual design studies for the Toroidal Field (TF) coils of DEMO, a solution based on a layer-wound magnet, rectangular-shaped Cable-in-Conduit conductors and W&R manufacturing approach, is being developed. The feasibility and performance of a large-size Nb3Sn conductor operating at about 82 kA in a 13 T field has been proven in the past. Another key technology to be demonstrated for a layer-wound TF coil, is that of a joint between two different conductor grades, to be possibly manufactured in-line during winding. The proposed joint solution would provide the minimum room occupancy, with the joint embedded within the winding pack volume. A joint between two low-field conductor grades, i.e., constituted of a small number of superconducting strands and a high number of stabilization copper wires, has been designed and manufactured. The two conductor lengths are characterized by a different number of superconducting wires and different outer dimensions. A joint sample has been assembled and instrumented, in the configuration allowing testing at the SULTAN facility of the Swiss Plasma Center. Both DC and AC performance of the joint has been characterized at the DEMO TF operating conditions. The present paper reports the main manufacturing steps for the joint and its main test results. The implications on the performance and design approach of the TF coil are also discussed, based on the outcome of such tests.

The U.S. Domestic Agency is one of the six suppliers of the toroidal field (TF) conductor for ITER. To qualify conductors per ITER requirements, we prepared or provided to the Swiss Plasma Center (SPC) eight test articles, sixteen conductors total, that were tested in the SULTAN facility at SPC in the ITER relevant conditions. The strands that were used in these SULTAN samples were fully characterized in the laboratories. In this paper, we report both test results and analysis of the conductors’ performance against expected strand performance. The U.S. TF conductors showed a slightly better than average current sharing temperature and a relatively low sensitivity to warm up-cooldown cycles in comparison with other suppliers’ conductors. However, the trend in current sharing temperature versus cycles and warm ups did not saturate, which means a continuing slow degradation of the conductor performance if the number of warm up and cooldown cycles will be significantly higher than expected. The ac losses in the U.S. TF conductors are in line with losses in the other TF conductor suppliers.

The present study aims to reduce the outer radius of the central solenoid (CS) with respect to its nominal size specified by EUROfusion for a maintained CS magnetic flux. A reduced outer CS radius would allow the reduction of the overall size and cost of the DEMO magnet system. The proposed outline design of the winding pack for the CS1 module is based on layer winding. To achieve the same magnetic flux in a CS coil of significantly reduced outer radius the peak magnetic field at the CS conductors needs to be substantially increased. The use of high-temperature superconductors is therefore envisaged in the highest field sections of the CS coil. It is planned to use react & wind Nb3Sn conductors for intermediate field sections and NbTi at the lowest fields. In order to make a most economic use of the superconductors the proposed winding pack design considers a superconductor grading.

This paper summarizes the work on the manufacturing and testing of conductor samples for ITER poloidal field 1&6 coils. The work was carried out by the IO and multiple institutions in the EU, Switzerland and Russia. Five samples were manufactured and tested in the SULTAN test facility. Analyses of dc performances, ac, and mechanical losses test results have been performed. All measurements were carried out before and after cyclic mechanical load created by the electromagnetic forces. DC test results of all samples tested demonstrated that the conductor performances are not affected by cycling mechanical load and meet the required value of current-sharing temperature T cs ≥ 5.8 K at magnetic field B max = 6.4 T and operating current I op = 48 kA. Measurements of the ac and mechanical losses were performed by gas flow calorimetric method. AC loss measurements were carried out at different operating currents and background magnetic fields. AC loss of tested samples showed no change under cycling mechanical load, but showed a correlation of ac loss versus background magnetic field. Mechanical loss, as had been expected, decreased significantly after first ten cycles then reaches a stabile value. The value of mechanical loss even in virgin condition does not affect workability of a magnet.

The article discusses the dramatic history of the Tsaritsyno Park and museum-reserve. By the mid-2000s, it had become one of Moscow's iconic places and a zone where urban public culture was shaped. The authors trace the history of this architectural ensemble and park in terms of their role in сity culture and analyse changes in the historical culture of contemporary post-Soviet Moscow. The Tsaritsyno Park and museum exemplify these changes. An unfinished country residence of Catherine II, with a Grand Palace that had stood as a ruin for over 200 years, it has been radically renewed by the Moscow city authorities in what came to be labelled ‘fantasy restoration’. The palace was finished and now serves as the core of the museum, organized according to a controversial historical policy. Tsaritsyno as a whole became a cultural oddity featuring historical attractions for the public, effectively an ‘eighteenth-century theme park’.

The Swiss Plasma Center (SPC) has developed a layout of Toroidal Field (TF) coil for EUROfusion DEMO tokamak, based on the reference tokamak baseline of 2015. Each TF coil winding pack is wound with graded Nb 3 Sn conductors and consists of 12 single layers, connected in series by means of inter-layer graded joints. The design of inter-layer joints takes into account the react-and-wind (R&W) manufacturing technique for fabrication of TF coil winding pack, i.e., the inter-layer joint is prepared with use of two already heat treated Nb 3 Sn conductors. The development, preparation and test of inter-layer joint at SPC is performed in frame of R&D program for TF coil of EUROfusion DEMO tokamak. The high-grade Nb 3 Sn TF conductor, operating at 63.3 kA and 12.2 T (T cs >6.5 K) was tested at SPC, and afterwards was used for fabrication of inter-layer joint. The developed TF inter-layer joint is an “overlap-type” joint, which can be fit within the dimensions of TF winding pack. Each end of two conductors is copper cladded by a thermal-spraying technique and then bonded together along the surfaces of cladded copper with use of a high-frequency inductor. This paper describes the design of inter-layer joint, process of joint fabrication and test results obtained at SPC at the SULTAN test facility.

Sedlak, K. et al., The European DEMO, i.e. the demonstration fusion power plant designed in the framework of the Roadmap to Fusion Electricity by the EUROfusion Consortium, is approaching the end of the pre-conceptual design phase, to be accomplished with a Gate Review in 2020, in which all DEMO subsystems will be reviewed by panels of independent experts. The latest 2018 DEMO baseline has major and minor radius of 9.1 m and 2.9 m, plasma current 17.9 MA, toroidal field on the plasma axis 5.2 T, and the peak field in the toroidal-field (TF) conductor 12.0 T. The 900 ton heavy TF coil is prepared in four low-temperature-superconductor (LTS) variants, some of them differing slightly, other significantly, from the ITER TF coil design. Two variants of the CS coils are investigated—a purely LTS one resembling the ITER CS, and a hybrid coil, in which the innermost layers made of HTS allow the designers either to increase the magnetic flux, and thus the duration of the fusion pulse, or to reduce the outer radius of the CS coil. An issue presently investigated by mechanical analyzes is the fatigue load. Two variants of the poloidal field coils are being investigated. The magnet and conductor design studies are accompanied by the experimental tests on both LTS and HTS prototype samples, covering a broad range of DC and AC tests. Testing of quench behavior of the 15 kA HTS cables, with size and layout relevant for the fusion magnets and cooled by forced flow helium, is in preparation., This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014–2018 and 2019–2020 under grant agreement No 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. This work was supported in part by the Swiss National Science Foundation (SNF) under contract number 200021_179134.

The Comprehensive Research Facility for Fusion Technology (CRAFT) project has been launched in 2019, for developing the essential engineering technologies for Chinese Fusion Engineering Testing Reactor (CFETR). Within this project, a full-size toroidal field (TF) coil will be built as the prototype coil for CFETR. Based on design of CFETR magnet system, the TF coil will operate at 95.6 kA in a peak field of 14.5 T. The high-J c Nb3Sn strand is taken into consideration due to the critical current density of ITER-grade Nb3Sn is too low at 14.5 T. Considering that it will be the first time to apply the high-J c Nb3Sn strand in the large-scale cable-in-conduit conductor (CICC) for fusion magnet, a conductor sample made of high-J c Nb3Sn strand with short twist pitch (STP) cable pattern was manufactured in ASIPP and tested in SULTAN facility, to investigate the feasibility. The test campaign focuses on the impact of cyclic electromagnetic (EM) loading and warm-up cool-down (WUCD) to the performance of the conductor, the strain distribution of the conductor before and after EM cycles was measured by inductive method to make a deeper insight of the conductor performance evolution. AC losses tests have also been carried out, providing relevant information for further coil design.

The series production of Nb3Sn and NbTi cable-inconduit conductors (CICC) for the winding of various coils in the International Thermonuclear Experimental Reactor (ITER) magnet system is being completed in 2015. The tests of the ITER conductor samples are running in the SULTAN test facility in Villigen, Switzerland, in the scope of a framework contract, flanked by six bilateral agreements between IO and the Domestic Agencies (DAs) of China, EU, Korea, Japan, Russian Federation, and USA. The key acceptance parameter of the tests for the conductor samples made from the series production ITER CICCs is the current sharing temperature Tcs at the nominal operating field and current after applied electromagnetic cyclic loadings at the nominal field and sinusoidal swing of conductor current from zero to nominal one. The Tcs is defined as the maximum temperature at which the conductors operate (nominal current and field) before developing an electric field of 10 μV/m. This paper gathers the latest test results of the ITER series production CICC. The qualified conductor units will be used in the winding of the toroidal field and poloidal field coils, as well as the central solenoid. The test results for the series production conductors are compared with the results of the conductors tested at the early stages of their development. The performance variation among the suppliers and the performance evolution since the start of the conductor production are discussed as well.

The main coils of the new European DIPOle (EDIPO) test facility, which is able to provide a background magnetic field up to 12.35 T, were commissioned at the Center for Research in Plasma Physics in July 2013. A field homogeneity of +/-1% was achieved over a 900-mm length, as compared to SULTAN's 10.9 T over 425 mm. To complete the commissioning of the test facility, the new superconducting transformer has been operated in 2015, and a high-current NbTi sample, which was earlier tested in the SULTAN test facility, has been tested in EDIPO under the same conditions as in SULTAN to benchmark the results. During the initial commissioning of the 100-kA transformer in 2013, the primary coil was found to be insufficiently cooled due to the debonding of the primary winding from its former that also served as the liquid helium cryostat. The NbTi primary coil was therefore modified to be in direct contact with liquid helium. At the next attempt of commissioning, in March 2014, a mechanical failure due to the imperfect alignment of the primary and secondary windings caused major damage. A replacement primary coil, which was wound in Summer 2014, was used in the third commissioning campaign in November 2014, but it failed due to the poor impregnation of the NbTi winding. Eventually, the original primary winding was repaired and commissioned in April 2015. The commissioning included a calibration of the current meter for the secondary winding and the high-current test, i.e., up to 95 kA at various background fields, of the “Trasek” conductor sample, which is a rectangular cable-in-conduit conductor made of 324 SnAg-coated NbTi strands. An excellent agreement was found between the results obtained from the two facilities. The sample holder unit is also equipped with a high-temperature superconducting (HTS) adapter and a counterflow heat exchanger to allow testing in EDIPO of HTS high-current samples over a broad range of operating temperatures, from 4.5 up to 50 K.

Analysis of the ac and mechanical losses of PF RF ITER SULTAN sample test results has been performed. Measurements were provided by the gas flow colorimetric method before and after cyclic mechanical loads. The mechanical loss investigation was carried out for the virgin sample and after 10, 400, and 1000 cycles. Mechanical loss, as it was expected, significantly decreased after the first ten cycles but remained almost the same after the subsequent cycling. The value of mechanical loss even of the virgin sample does not strongly affect the workability of a magnet. AC loss measurements were carried out at different operating currents in conductor, at background magnetic field of 2 and 4.5 T before and after cycling. The ac loss measurements of all tested samples were practically the same before and after cycling, but strongly depended on a background magnetic field. As an example, at zero operating current in conductor and variable magnet field frequency of 6 Hz, the ac loss decreased by ∼1.4 times at background magnetic field of 4.5 T compared with the loss at 2.0 T. An attempt to explain the phenomena has been done. The results of the calculation and experimental investigation are presented.

The performance of two mass-produced Nb3Sn conductors for the ITER central solenoids was tested for the first timmass-produced Nb3Sn conductorse. One was cut from the forward end of an 80-m-long conductor, and the other was cut from the forward end of a 918-m-long conductor. The fifth-stage twist pitches of these conductors were lengthened by approximately 16% during cable insertion and compaction with conduit. The current sharing temperatures Tcs were measured over 20 000 electromagnetic cycles, including four thermal cycles between 4.2 K and room temperature. The Tcs of the former conductor increased and became almost constant through the cycling. In contrast, Tcs of the latter conductor not only increased but also decreased slightly against cycling. The Tcs decline rate after 10002 cycles was -4.50 × 10-6 K/cycle. If this rate is assumed to continue after 20000 cycles, Tcs would decrease by -0.27 K over 60000 cycles. Even so, Tcs is higher than an acceptance criterion of 6.5 K at 60 000 cycles. The ac losses Q of both conductors at a current of 0 kA were almost the same as or slightly lower than Q of a short sample conductor whose fifth-stage twist pitch was not lengthen. On each conductor, Q at 40 kA was approximately 10% higher than that at 0 kA; thus, the effect of the transport current on Q was not large.

The correction busbar (CB) conductors for the ITER project are being produced in China. The second China CB conductor sample (CBCN2, Phase II of conductor testing) and the third CB conductor sample (CBCN3, Phase III testing) were made of the WST NbTi strands, cabled by Changtong, jacketed at ASIPP, and tested in the SULTAN facility. The current sharing $(T_\mathrm{cs})$ test results show that the conductor sections of CBCN2 and CBCN3 have high $T_\mathrm{cs}$ performance. Using the electrical method, the $T_\mathrm{cs}$ of both CBCN2 and CBCN3 samples was 7.50 K at 10 kA/2.9 T (maximum operating field) before and after electromagnetic loading. AC loss measurement was performed before any electromagnetic loading of the sample, and the measurements were repeated after 1000 or 2000 cyclic loads. The AC loss measurements were performed at 2-T background field, without transport current. The ac loss of the CBCN2 and CBCN3 conductors slightly differs at ±0.2T ac field and various frequencies. According to the SULTAN test result, $T_\mathrm{cs}$ of CBCN2 and CBCN3 conductor samples meet the ITER acceptance criteria of 7.0 K at Bpeak field is 2.9 T and 10 kA.

The article describes basic approaches to conducting an efficiency assessment of a nuclear object physical protection system as well as the possibility of creation of the intruder analytical model to determine time indicators of overcoming nuclear object protection boundaries by an intruder with defined characteristics. An intruder uses different tactics and methods to overcome boundaries of protection. A multivariate analysis lays in a basis of research that taking into account psycho-physiological and physical properties of the human organism, intruder equipment level for overcoming of physical barriers.

Direct current tests performed in the past on the conductor samples of the toroidal field (TF) ITER coils revealed degradation of current sharing temperature, T cs. The degradation progresses with repetitive electromagnetic loading, and also with thermal cycles between 4.5 K and room temperature. This feature was observed on short samples in SULTAN test facility (EPFL-SPC, Switzerland) as well as in TF Insert Coil tests in CSMC test facility (Naka, Japan). We present three independent observations suggesting that initiation of sample quench followed by a fast current discharge, which normally complements every I c and T cs test in both SULTAN and CSMC, enhances the T cs degradation rate. The exact mechanism of this contribution to the degradation remains unidentified.

In 2013, the EUROfusion organization launched the preconceptual design studies of the fusion DEMO tokamak. Several options of superconducting magnet design are investigated within the scope of the project. The magnets based on Nb3Sn, namely the Toroidal Field (TF) and Central Solenoid (CS) coils, can be made either using the Wind&React technology, as in ITER, or React&Wind (RW) technology with potentially significant cost-saving benefits. Within the R&D program of the Swiss Plasma Center, the first full-size DEMO TF RW conductor prototype, RW1, was manufactured and tested in 2015–2016. The second, improved prototype, RW2, was built and tested in 2017–2018. The experimental results collected over several test campaigns performed on four assemblies of RW2 rated for 63 kA at 12.23 T are presented. The current sharing temperature $T_{{{cs}}}$ of the latest RW2 assembly in DEMO operating conditions reached 7.16 K after 1000 electromagnetic cycles and four thermal cycles. This $T_{{{cs}}}$ corresponds to the effective strain ϵeff = −0.27%, significantly exceeding the design requirement of $T_{{{cs}}}\,\geq \,\text{6.7}\,\text{K}$ . If RW2 have been used in ITER TF coils, the $T_{{{cs}}}$ at 68 kA and 10.9 T would be 7.42 K, i.e., approximately 1 K higher than most of the ITER TF samples, and that with only 55% of Nb3Sn used in ITER TF conductor. The tests of RW2 proved that the cost-saving potential of the React&Wind technology is enormous.

The ITER Toroidal Field (TF) coil winding packs are designed to be wound in double-pancakes. The twin-box joint provides the electrical pancake-to-pancake connection between the two Nb3Sn 68 kA conductors and electrical coil-to-bus bar connection between the IF coil terminations and NbTi 68 kA bus bars conductors. The twin-box full size joint sample connecting two Nb3Sn conductors (pancake-to-pancake joint) was prepared in order to qualify the TF joint assembly in SULTAN Test Facility. The original goal of the test program was the measurement of joint resistance at different operating conditions. The accidental dump of the SULTAN background field caused a noticeable increase of resistance due to the induced electromagnetic transient load. The TF joint test was continued in order to investigate a change of joint resistance following electromagnetic transient loading which was triggered by intentional dump of the background field. Also, a dependence of the joint resistance on current was observed; in order to explore the origin of resistance change, additional experiments were performed with a modified (artificially degraded) TF twin-box joint. The test results of a TF twin-box joint after electromagnetic transient loading and performance of the joint after a modification are presented in this paper. The performance of Nb3Sn 68 kA conductor observed during those tests is highlighted as well. (C) 2015 Elsevier B.V. All rights reserved.

Japan Atomic Energy Agency (JAEA) is procuring 100% of the ITER Central Solenoid (CS) conductors. The CS conductor is required to maintain the performance under 60000 pulsed electromagnetic cycles. JAEA tested two internal-tin Nb3Sn conductors for the CS at the SULTAN test facility. As a result of destructive examination, the twist pitches of both of the cables satisfied requirements of the ITER Organization (IO). The current sharing temperatures Tcs of each sample were 6.6 and 6.8 K before cyclic operation, and the Tcs values were 6.8 and 6.9 K after 9700 electromagnetic cycles, including three warm-up/cooldowns, respectively. The Tcs performance of both samples satisfied the IO requirement. The ac losses of CSKO1-C and CSKO1-D were approximately half of typical bronze-route CS conductors at 2 and 9 T. The ac loss at 45.1 kA after the cycling was 1.5 times higher than that without the transport current. An almost constant strain of the jacket was observed after the test as a result of the residual strain measurement. Therefore, the deformation of the cable might have been homogeneous along the conductor axis. Because of the higher Tcs of CSKO1-D than CSKO1-C, JAEA started the manufacturing of the CS conductor with the same specification as CSKO1-D.

The tilted head race track coils of the EDIPO test facility are wound with cable-in-conduit conductors made by high current density Nb3Sn strands, Jc = 2400 A/mm2 at 12 T – 4.2 K. Since the commissioning of the coils, frequent voltage spikes were observed at the quench detection taps during the low current range of operation, completely disappearing above 2 T. The large amplitude of some spikes triggered the quench detection system: the parameters for protection (voltage thresholds and validation time) had to be modified for the voltage pairs monitoring the windings. The occurrence of partial flux jumps in the high current density strands is known from former characterization. The fast data acquisition of the quench detection system, with 800 Hz sampling frequency, allows investigation of the dynamics and propagation of the voltage spikes in the various layers of the winding. From the collected data of several runs of operation, statistics of amplitude, initial location, propagation and reproducibility were drawn, looking also for correlation with the operation history, e.g. first cooldown, ramp up vs. ramp down, ramp rate, etc. The energy released by the flux jumps is conservatively estimated by the time integration of the voltage spikes and discussed in terms of energy margin and heat removal rate in the layers. In conclusion, the limitation of the use of high current density Nb3Sn strands in high current conductors is discussed.

Four ITER main busbar (MB) conductor samples were tested in the SULTAN test facility (Centre de Recherches en Physique des Plasma, Ecole Polytechnique Fédérale de Lausanne, Switzerland) between 2011 and 2013. The MB conductors are NbTi-based cable-in-conduit conductors (CICCs), and they will become part of the feeder system of the ITER magnets. The measured dc performance of the four MB samples varied significantly, supposedly depending on the design of the bottom terminations. Two out of three samples with a U-bend box, made of a continuous conductor section, exhibit approximately 0.5 K lower current-sharing temperature Tcs than the sample with a solder-filled bottom joint, consisting of two straight conductor sections. We assess the theoretically expected Tcs performance of the MB conductor based on the characterization of individual NbTi strands, on the ITER NbTi scaling law, and on the magnetic field distribution across the cable cross section. The magnetic field in a SULTAN sample consists of three components, namely, the background SULTAN field, the self-field generated by the current in the conductor under test, and the magnetic field generated by the current in the return conductor. Taking into account all the three components, we calculate the average electric field in the cable and determine Tcs as in the experiment, namely, as the temperature at which the electric field reaches the critical value of Ec=0.1 μV/cm. The theoretically assessed Tcs confirms that the MB sample with solder-filled joint behaves as expected.

In summer 2015, a new reference baseline is issued for the DEMO EUROfusion tokamak. Thereafter, the toroidal field (TF) coils have been updated with the new layout of the react-and-wind conductor proposed by the Swiss Plasma Center (SPC). Each TF coil consists of 12 single layers of graded Nb3Sn conductors connected in series by “invisible” inter-layer joints fully embedded in the winding pack. The high-grade Nb3Sn conductor operates at 63 kA, 12.2 T with Tcs > 6.5 K. The new prototype of the high-grade cable had been manufactured by ENEA at TRATOS, Italy, and delivered to SPC: 20 m of Nb3Sn and about 10 m of copper dummy conductor. The SULTAN conductor sample consisting of two identical, beforehand heat-treated conductors was prepared and tested at SPC in May–June 2017. Upon the completion of comprehensive conductor tests, the one of those conductors was used for manufacturing of the designed at SPC potentially applicable inter-layer TF joint. The conductor was cut, and then, joined again in accordance with the developed at SPC design of inter-layer joint. The SULTAN sample comprising the earlier tested non-destroyed conductor and the earlier tested, but then cut and joined conductor was re-assembled and tested in the SULTAN test facility at SPC in August 2017.

The ReactW –0.30%. After the baseline of the DEMO device was updated in 2015, the new requirements led to an updated conductor design, for 63 kA at 12.2 T. The manufacturing experience of the first prototype, named RW1, is exploited in a second short-length prototype conductor, named RW2, assembled and tested in 2017: The conductor aspect ratio is reduced, and the segregated copper wires are replaced by a solid block of mixed matrix stabilizer. Although designed for the TF coils, with dc operation, the moderate ac loss of the flat cable makes the RW2 a good candidate also for the central solenoid conductor. The Nb3Sn strand for RW2 is supplied by WST (PRC), and the flat cable is made at TRATOS (Italy). The rationale of the design, the conductor manufacture, the sample assembly, and the test results in SULTAN are reported.

The paper presents an approach to evaluating the effectiveness of physical protection systems (PPS). Considering the fact that different processes are subject to universal physical laws and principles of development, a parallel was drawn between the concepts of conflict resolution field to description of interaction in the system “outsider – PPS”. The description of mathematical model in the form of dependence with respect to the real conflict in the system “outsider – PPS” is given. The result of the model analysis is determination of the parameter, allowing estimating the rate of threat increase in conflict situation. Also competence of PPS operator is considered in the framework of the work. Furthermore, actions of operator were taken as a key factor affecting the efficiency of the whole security system. To resolve identified issues ways to develop special qualities required for the operator and their professional skills through training were suggested. Also the issues of control of psychophysiological characteristics of PPS staff were addressed.

The EDIPO test facility is erected at CRPP Villigen with the aim of providing a flexible, high field test bed for high current force flow superconductors. The EDIPO main coil is a tilted-head race-track pair wound by a graded Nb3Sn cable-in-conduit conductor. The whole project, partly funded by the European Commission, started in 2004 and entered the commissioning phase in 2013. The final steps of instrumentation and installation of the main coil, delivered by industry in May 2011, lasted about 18 months. The first cool-down of the facility started in November 2012. The commissioning of the main coil, including the precise measurement of the generated magnetic field, was carried out in March 2013. At an operating current of 17.2 kA, a +/- 1% homogenous field of 12.35 T was generated over a length of 900 mm in the center of the test well, 140 mm x 91 mm in cross section. Details about cool-down, flux jumps, forces and displacements, field map, and charging rate are presented in this paper.

The optimization of the heat treatment of Nb3Sn conductors for toroidal field coils in ITER was attempted to improve the current sharing temperatures (Tcs). Using the strand, we chose the pattern at 570°C for 250 h and 650°C for 100 h as the best, which increased the critical current and maintained the residual resistivity ratio higher than 100. The behavior of the critical current of the strand vs. the magnetic field, temperature, and strain was also improved. This pattern was used on two conductors, and their performances were tested. Tcs was evaluated over 1000 electromagnetic cycles and one thermal cycle. A sharp Tcs degradation occurred at 50 cycles. Then Tcs decreased linearly. Although this tendency was similar to the conductors that were heat treated with the original pattern, the degradation rates were improved. The ac losses (Q) before cycling were approximately 10% lower than those of the original pattern. Q after cycling became almost equivalent between two patterns. The conductor was inspected after the test, which showed that the conductor under the high-magnetic-field zone had contracted by approximately 600 ppm during the test. Some clearly deformed strands were observed under the high-magnetic-field zone, which could degrade Tcs.

The performance of four Nb3Sn conductors for the ITER central solenoids was tested. The current sharing temperatures (Tcs) were measured over approximately 9000 electromagnetic cycles, including two or three thermal cycles between 4.2 K and room temperature. Tcs increased and became almost constant through the cycling. The gradient of the electric field against the temperature gradually decreased against cycling. The degradations caused by the electromagnetic force of the short twist pitch conductors were smaller than that of the original twist pitch conductor. The ac losses of short twist pitch conductors were several times higher than that of original twist pitch conductor. The dents and the removals of the Cr plating on the strands, which were formed during cabling, decreased the electric resistance between strands, which may cause the observed high ac loss. Inspection of the cable showed neither a clear bias of cable in the cross-sectional surface nor distorted strands in the lateral face. The high rigidity of the short twist pitch cable could prevent these plastic deformations, caused by the Lorentz force.

The tests of the ITER Toroidal Field (TF) full length conductors (hundreds of meters, production phase IV) were started at the end of year 2012 and were performed accordingly to the firmly specified test program. The TF conductors produced by the ITER domestic agencies (European Union, Japan, Korea, and Russian Federation) passed the qualification tests to be used for the TF coil winding. The four ITER Central Solenoid (CS) conductors produced in Japan were tested in frame of supplier qualification tests in order to verify the improved design of the CS conductor operating in cyclic mode and, thus, to solve the issue of drastic performance degradation with electromagnetic cyclic loading observed earlier. The test results of the recently tested ITER conductors are summarized in this paper, and the specific features of the voltage-temperature (VT) evolution in Nb3Sn conductors during the qualification test campaigns are highlighted and compared with earlier tested conductors.

Manufacturing of superconducting Nb3Sn based Cable-in-Conduit Conductor (CICC) for Toroidal Field (TF) coils for the ITER tokamak under the responsibility of the ITER Domestic Agency for the Republic of Korea, ITER Korea, has been in progress since early 2012. Production of sufficient CICC needed to fabricate the first TF coil solely using Korean (KO) conductor has been achieved. Furthermore, low temperature performance verification tests near ITER operating conditions on a second CICC sample, following tests on a sample from the first KO CICC destined for an ITER TF coil, have recently been performed at the EPFL-CRPP SULTAN facility in Villigen, Switzerland. This paper provides an overview on all CICC that is destined for the first ITER TF coil to be fabricated with KO CICC, along with a brief summary of the results of the low temperature performance verification tests on KO CICC samples.

The study of post-World War II historical periodicals in the historiography of Soviet science was devoted par excellence to certain journals. These were studied in the context of contestations between politics and bureaucrats, on the one hand, and scholars, on the other. This article will consider the whole system of periodicals in the field, focusing on its substantial transformations in the 1950s–1960s in the context of the evolution of both academic institutions and the publishing industry. The description of the changes in the corpus of journals and its functioning, the transformation of the evaluation system, the emergence of new communication strategies, and forms of representation of historical knowledge are based on an analysis not only of journals themselves, but also on archival documents and relevant statistical data.

In the assumption that DEMO will be an inductively driven tokamak, the number of load cycles will be in the range of several hundred thousands. The requirements for a new generation of Nb3Sn based high current conductors for DEMO are drafted starting from the output of system code PROCESS. The key objectives include the stability of the DC performance over the lifetime of the machine and the effective use of the Nb3Sn strand properties, for cost and reliability reasons. A preliminary layout of the winding pack and conductors for the toroidal field magnets is presented. To suppress the mechanism of reversible and irreversible degradation, i.e. to preserve in the cabled conductor the high critical current density of the strand, the thermal strain must be insignificant and no space for micro-bending under transverse load must be left in the strand bundle. The "react-and-wind" method is preferred here, with a graded, layer wound magnet, containing both Nb3Sn and NbTi layers. The implications of the conductor choice on the coil design and technology are highlighted. A roadmap is sketched for the development of a full size prototype conductor sample and demonstration of the key technologies. (C) 2012 Elsevier B.V. All rights reserved.

Within the frame of the R&D activities carried out in Europe for the toroidal field coils of the nuclear fusion device DEMO, a fundamental milestone was considered to be the demonstration of Nb3Sn cable-in-conduit conductors (CICC) performance in the demanding range of interest for DEMO. Among the different technological solutions envisaged, the present paper deals with a wind & react CICC solution, with rectangular geometry, thick steel jacket, and distributed pressure relief channel, designed to operate at 82 kA in a magnetic field of 13 T and with a current sharing temperature ${\rm{T}}_{{\rm{cs}}}\,{\rm{> \,6.5\,K}}$ . The main manufacturing steps of the prototype conductor are described in the present paper, carried out within industrial environment, partly using the facilities and procedures available for the manufacture of ITER conductors. A sample was designed for the EDIPO facility at the Swiss Plasma Center, Switzerland, in the configuration usually adopted for the test of ITER poloidal field conductors, where the two straight conductor legs are part of the same cable length, with a continuous transition through a bottom hairpin-type joint, thus avoiding any resistive connection. The conductor has been characterized in terms of dc performance at relevant operating conditions and the absence of any performance degradation with electro-magnetic load cycles has been verified, thus, qualifying the proposed technological solution. AC losses and thermo-hydraulic tests have also been carried out, providing relevant information for further coil design.

Since the year 2013, the Swiss Plasma Center (SPC) has proposed a Toroidal Field (TF) layout for the DEMO- EUROfusion tokamak, based on a graded winding pack made of layers of Nb3Sn (react-and-wind) conductors. In summer 2015, a new reference baseline is issued for the DEMO- EUROfusion tokamak, leading to an update of the TF coil requirements, e.g. the operating current has been reduced from 80 kA to 63 kA. Consequently, the conductor layouts for every graded layer of the TF coil winding pack is re-designed in order to match the new requirements. Each layer of TF coil winding pack has to be connected electrically in series to form the coil. The inter-layer Nb3Sn splice joint design which does not exceed the conductor dimensions is proposed in this paper for the updated 63 kA Nb3Sn TF conductor. This proposed joint design allows a continuous winding of TF coil winding pack from layer to layer, housing the joint at the zone of inter-layer transition. Ultimately, the all inter-layer joints should be arranged within the winding pack at the low-field and low mechanically stressed region of D-shaped TF coil.

The article discusses the main issues related to the training and retraining of security services as well as those related to the design, implementation and evaluation of physical protection systems (PPS). The emphasis is on modeling the protected object and creating a "program-information environment" for the construction and evaluation of the main PPS parameters. The paper also presents the main PIE blocks.

The Japan Atomic Energy Agency (JAEA) developed ITER TF Nb3Sn conductors that fulfill ITER requirements and has commenced fabricating the conductors to be used in the ITER TF coils. As a qualification of conductor fabrication, two full-size conductor samples, named as JATF4, were prepared and tested by the SULTAN facility at CRPP in Switzerland. Temperature sensors and voltage taps were attached on the three meter-long conductor samples to measure the current sharing temperature (Tcs). Measurements were performed at the beginning of the testing campaign, during cyclic test, and at the end of the campaign following a warm up and cool down. The Tcs values electrically assessed by the agreed procedure at outer magnetic fields of 10.78 T initially were 6.5 K and 6.2 K, and then 6.1 K and 6.0 K at the end of the campaign for each conductor, respectively. These results demonstrate that the conductors have a sufficient Tcs margin to satisfy the ITER TF conductor criterion of 5.7 K, and conductor fabrication is qualified. Details of the test results are presented and discussed.

In the framework of the ITER Qualification Tests the Russian sample RFTF2 was tested in SULTAN facility. The sample is made of two identical ITER TF-type cable-in-conduit conductor sections. Bronze route strands were used for the conductor fabrication. The main characteristics of the conductor and the strand are presented as well as the sample assembly details. The test was performed in accordance with the ITER International Organization specified program. In order to evaluate the conductor performance, the current sharing temperature was measured at specified electromagnetic load cycling steps. Few voltage-current characteristics were measured with the aim of n-value estimation. Both conductor sections of the RFTF2 sample showed identical performance: the current sharing temperature is 6.4 K, that not only satisfies, but substantially exceeds ITER requirement of 5.7 K. The tests of RFTF-2 conductor sample showed that electromagnetic cyclic load as well as warm-up had negligible effect on the conductor performance. The results of the SULTAN sample test are compared with strand performance.

In the framework of the JT-60SA design activities, EU home team has defined a reference layout for the Toroidal Field conductor: it is a slightly rectangular Cable-In-Conduit NbTi conductor, operating at 25.7 kA with a peak field of 5.65 T. ENEA has assigned LUVATA Fornaci di Barga the task to produce the strands and to perform cabling, whereas jacketing and compaction have been carried out in its own labs. The sample, successfully tested at the CRPP SULTAN facility, has been assembled in such a way as to avoid the bottom joint between the two legs, thus using a single conductor length (about 7 m). An ad-hoc developed solution to restrain the U-bent conductor section (where jacket is not present), consisting in a stainless steel He-leak tight box with an inner structure designed in order to completely block the cable, has been also developed and manufactured by ENEA, where the sample has been also assembled. Instrumentation installation and final assembly of the sample have been performed by the SULTAN team. The main aspects of the sample manufacturing and characterization are here presented and discussed.

Since it is practically impossible to remove the Poloidal Field (PF) coils from the assembled ITER (International Thermonuclear Experimental Reactor) tokamak without major interruption in operation, the design of these coils shall provide their high reliability under high voltage operation. The design of the coil insulation relies on a separation of functions: mechanical function of the load transmission, performed by glass-fiber impregnated with epoxy resin on one side, and the independent electrical barrier made of polyimide tapes on the other side. Numerical simulation has shown that the maximum electrical field in the coil is lower than 4 kV/mm, which is taken as the design criterion for the PF insulator system. In case of a single insulation failure in a coil, its functionality can be recovered by installing a so-called jumper to by-pass the faulty double pancake. The design of the jumpers and their installation procedure are described.

Many full size conductors for the ITER TF coils have been tested at the SULTAN test facility in Switzerland for conductor qualification. JAEA tested two samples and two kinds of Nb3Sn strands were evaluated through the tests. Now another sample named JATF3 has been tested, which uses two other kinds of Nb3Sn strands. The strands satisfy the critical current density Jc requirement, but results of the conductor test were lower than our expectation. After the test, JAEA has been investigating the reason by X-ray CT scan and destructive inspection, and has found a possible reason.

The US Domestic Agency is one of six parties supplying TF cable-in-conduit conductors (CICCs) for ITER. Previous tests have shown that measured performance of the TF CICCs can be much lower than expected from the strand properties at the projected uniaxial strain and that the cabling pattern may also be an important factor. Worst of all, voltage signals well below the expected critical surface could not be reliably interpreted or canceled, making test results very suspect. The TFUS1 sample was prepared to achieve multiple goals: 1) to ensure uniform current distribution and to eliminate parasitic voltage signals by improving joints, 2) to explore the potential benefits of a different cabling pattern for better support of strain-sensitive strands, and 3) to explore the source of voltage development in the cable through the use of innovative penetrating diagnostics. Test results of the first US-made samples are presented and discussed.