Some Notes on the Leipzig–Jakarta List of the Chulym Language

Based on the analysis of the most resistant words (Leipzig–Jakarta list) of Chulym Turkic in comparison with those of the Oghuz and Kipchak languages, authors come to a conclusion that Chulym Turkic is more similar to the Kipchak Turkic languages than the Ohguz ones. The Chulym Turkic material for the analysis is field dialectological data. The words of other languages under study were taken from dictionaries. The comparative method was used as the main research method. Previously, Chulym Turkic was considered as one of the Siberian Turkic languages also including Khakass, Shor and Saryg-Yughur, to which the authors disagree

On the Hardness of Category Tree Construction

Category trees, or taxonomies, are rooted trees where each node, called a category, corresponds to a set of related items. The construction of taxonomies has been studied in various domains, including e-commerce, document management, and question answering. Multiple algorithms for automating construction have been proposed, employing a variety of clustering approaches and crowdsourcing. However, no formal model to capture such categorization problems has been devised, and their complexity has not been studied. To address this, we propose in this work a combinatorial model that captures many practical settings and show that the aforementioned empirical approach has been warranted, as we prove strong inapproximability bounds for various problem variants and special cases when the goal is to produce a categorization of the maximum utility. In our model, the input is a set of n weighted item sets that the tree would ideally contain as categories. Each category, rather than perfectly match the corresponding input set, is allowed to exceed a given threshold for a given similarity function. The goal is to produce a tree that maximizes the total weight of the sets for which it contains a matching category. A key parameter is an upper bound on the number of categories an item may belong to, which produces the hardness of the problem, as initially each item may be contained in an arbitrary number of input sets. For this model, we prove inapproximability bounds, of order ??(?n) or ??(n), for various problem variants and special cases, loosely justifying the aforementioned heuristic approach. Our work includes reductions based on parameterized randomized constructions that highlight how various problem parameters and properties of the input may affect the hardness. Moreover, for the special case where the category must be identical to the corresponding input set, we devise an algorithm whose approximation guarantee depends solely on a more granular parameter, allowing improved worst-case guarantees. Finally, we also generalize our results to DAG-based and non-hierarchical categorization

The Role of Diffusion in ISOL Targets for the Production of radioactive Ions Beams

On line isotope separation techniques (ISOL) for production of ion beams of short-lived radionuclides require fast separation of nuclear reaction products from irradiated target materials followed by a transfer into an ion source. As a first step in this transport chain the release of nuclear reaction products from refractory metals has been studied systematically and will be reviewed. High-energy protons (500-1000MeV) produce a large number of radionuclides in irradiated materials via the nuclear reactions spallation, fission and fragmentation. Foils and powder of Re, W, Ta, Hf, Mo, Nb, Zr, Y, Ti and C were irradiated with protons (600-1000MeV) at the Dubna synchrocyclotron and at the CERN PS-booster to produce different nuclear reaction products. The main topic of the paper is the determination of diffusion coefficients of the nuclear reaction products in the target matrix, data evaluation and a systematic interpretation of the data. The influence of the ionic radius of the diffusing species and the lattice type of the host material used as matrix or target on the diffusion will be evaluated from these systematics. Special attention was directed to the release of group I, II and III-elements. Arrhenius plots lead to activation energies of the diffusion process

Study of Defects of Longitudinal Welded Pipe

During the production of longitudinal electric welds by the method of high-frequency welding (HFW), defects of the longitudinal weld were revealed using X-ray inspection. For these defects, metallographic analysis was carried out, which showed that both the base metal and the welded joint met the requirements of regulatory documents. The chemical composition and mechanical properties also comply with the requirements of regulatory documents. Non-metallic inclusions of the liquation strips of the sheet, emerging on the edge and falling into the welding zone, were detected during X-ray inspection and were not correctly identified as a defect. This assumption is based on the coincidence of the position of the "grooves" in the zones of the welded joint with X-ray diffraction patterns, while the defects are not confirmed by other control methods and metallographic studies. Incorrect interpretation of defects during X-ray inspection occurs in the production of pipes [1-4] and requires additional verification or duplicate inspection. © 2022 American Institute of Physics Inc.. All rights reserved.Minobrnauki of Russia, (ȺȺȺȺ-Ⱥ -118020690196-3)Russian Foundation for Basic Research, РФФИ, (18-38-00253)The research was carried out within the state assignment of Minobrnauki of Russia (theme “Diagnostics” No. ȺȺȺȺ-Ⱥ -118020690196-3), supported in part by RFBR (project No. 18-38-00253)

Electric field gradients in MgB2_2 synthesized at high pressure: 111^111Cd TDPAC study and ab initio calculation

We report the high-pressure synthesis of novel superconductor MgB$_2$ and some related compounds. The superconducting transition temperature of our samples of MgB$_2$ is equal to 36.6 K. The MgB$_2$ lattice parameters determined via X-ray diffraction are in excellent agreement with results of our ab initio calculations. The time-differential perturbed angular correlation (TDPAC) experiments demonstrate a small increase in quadrupole frequency of $^111$Cd probe with decreasing temperature from 293 to 4.2 K. The electric field gradient (EFG) at the B site calculated from first principles is in fair agreement with EFG obtained from $^11$B NMR spectra of MgB$_2$ reported in the literature. It is also very close to EFG found in our $^111$Cd TDPAC measurements, which suggests that the $^111$Cd probe substitutes for boron in the MgB$_2$ lattice.Comment: 10 pages, 3 figure