Informacionnye Tehnologii

The paper presents the results of the All-Russian Youth Forum on Graphic Information Technologies and Systems «KOGRAF-2026», which was held on April 13—16, 2026 at the Nizhny Novgorod State Technical University named after R. E. Alekseev. The main events and thematic directions of the conference are described. A comparison with the forums of 2024 and 2025 is carried out. The selected publications describe current research in the fields of geometric modeling, BIM technologies, 3D data processing, robotics, artificial intelligence, additive manufacturing, and user interface evaluation. The article highlights current topics, trends, and development areas in graphic information technologies.

The paper considers the application of a hierarchical point cloud partitioning algorithm based on the BVH structure (Bounding Volume Hierarchy) aimed at reducing data volume while preserving morphological information. The study analyzes a partitioning algorithm based on a modification of the classical SAH (Surface Area Heuristic) cost criterion by supplementing it with morphological metrics. The main focus is on assessing the algorithm’s sensitivity to the weighting coefficients λ_D and λ_H, which determine the contribution of the proposed metrics — local density contrast (Δ_dens) and point distribution along a selected axis (Δ_height). The sensitivity analysis of the control parameters has shown that the introduced weighting coefficients exert a predictable influence on the partition structure. Experiments with varying point count thresholds in the nodes confirmed the ability to control the granularity of the resulting BVH structure and the segment size distribution, which allows formulating practical recommendations for parameter selection depending on the required level of detail. The experimental validation demonstrated the operability of the proposed algorithm and its applicability for generating morphologically homogeneous and semantically interpretable segments from laser scanning data of various structures.

The paper discusses an approach to forming an expert group for assigning coefficients in a regression test ranking approach for new information system development projects. A comprehensive set of ranking criteria for a regression test suite is proposed. An approach is formulated for assigning coefficients in the regression test ranking approach for new projects based on the expert evaluation method.

This study addresses the assessment of cumulative losses in two-stage cascade translation of geometric models between CAD systems. To account for losses repeatedly identified at successive transformation stages, a loss-overlap share (Δ) is introduced. The theoretical bounds of this quantity are derived from the loss coefficients of direct translations, and a normalized indicator is proposed for comparing routes with different loss levels. A total of 110 experiments were conducted using part and assembly models and neutral as well as system-specific data formats. In all cases, the calculated values of (Δ) were within the corresponding theoretically admissible intervals. The normalized values were predominantly concentrated near the upper bound, indicating substantial overlap between the losses of the first and second translation stages in the investigated sample. When the same format was used at both stages, the normalized loss-overlap share reached its maximum value. The proposed model is intended for interval estimation of cumulative losses in two-stage CAD translation routes.