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Unsupervised anomaly detection in time-series has been extensively investigated in the literature. Notwithstanding the relevance of this topic in numerous application fields, a complete and extensive evaluation of recent state-of-the-art techniques is still missing. Few efforts have been made to compare existing unsupervised time-series anomaly detection methods rigorously. However, only standard performance metrics, namely precision, recall, and F1-score are usually considered. Essential aspects for assessing their practical relevance are therefore neglected. This paper proposes an original and in-depth evaluation study of recent unsupervised anomaly detection techniques in time-series. Instead of relying solely on standard performance metrics, additional yet informative metrics and protocols are taken into account. In particular, (1) more elaborate performance metrics specifically tailored for time-series are used; (2) the model size and the model stability are studied; (3) an analysis of the tested approaches with respect to the anomaly type is provided; and (4) a clear and unique protocol is followed for all experiments. Overall, this extensive analysis aims to assess the maturity of state-of-the-art time-series anomaly detection, give insights regarding their applicability under real-world setups and provide to the community a more complete evaluation protocol.

ITER (International Thermonuclear Experimental Reactor) is a nuclear fusion research and engineering project. It is supposed to be the first fusion device to test the integrated technologies, materials and operational regimes necessary for the commercial production of fusion-based electricity. Front (explored in this paper) and Back diagnostic racks are used as supporting structures of the so-called ITER Divertor Thomson Scattering (DTS) Diagnostic System that is created to measure plasma characteristics. They will be attached to the lower port walls (ITER ports are used to locate diagnostic equipment and its supporting structures) through the so-called Divertor Rails. The developed design of the Front (Diagnostic) Rack locking (e.g. Rack attachment to the rails mechanism) was analyzed in this research to be consistent with thermal stresses, electromagnetic and seismic loads taking into account some specific assembly and maintenance loads including preloading under installation. The analysis of the rack locking design’s resistance to the mentioned loads should prove correspondence of the suggested common rack design with the structure integrity criterions. Construction strength under the most severe loading scenario was estimated in this research and appropriate conclusions were made. It was found out that the stress criterion was not fully satisfied, so a new rack locking design concept was proposed. Its main details are also described at the end of this article.

ITER is a nuclear fusion research and engineering project. It is supposed to be the first fusion device designed for testing the integrated technologies, materials, and physical aspects necessary for development of the commercially available fusion-power plant. One of the important components of the project is optical diagnostic systems with collecting mirrors. These mirrors have to provide stability of optical systems under severe loads of different types that could possibly arise in the tokamak. The collecting mirrors of several ITER diagnostics have a large scale and should be installed into diagnostic ports. Thermal stress analysis of the mirror updated design is aimed to obtain deformation and rotation values of the mirrors’ reflecting surfaces in order to conduct ray tracing analysis and to edit mirrors alignment to provide correct functioning of the optical systems. The maximum temperature values of the Divertor Thomson Scattering collecting mirrors were estimated for the normal operation mode. The FE model of the second mirror takes into account all the force boundary conditions, basic kinematic boundary conditions and constraints. Boundary conditions taken for the simulation were applied on surfaces contacting with the diagnostic rack. Thermally stressed state was calculated and corresponding displacement and rotation distributions were obtained.