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The concept of Neural Radiance Fields (NeRF) emerged in recent years as a method to create novel synthetic 3D viewpoints from a set of trained images. While it has several overlaps with conventional photogrammetry and especially multi-view stereo (MVS), its main point of interest is the capability to rapidly recreate objects in 3D. In this paper, we investigate the quality of point clouds generated by state-of-the-art NeRF in the context of interior spaces and compare them to four conventional MVS algorithms, of which two are commercial (Agisoft Metashape and Pix4D) and the other two open source (Patch-Match and Semi-Global Matching). Three synthetic datasets of interior scenes were created from laser scanning data with different characteristics and architectural elements. Results show that NeRF point clouds could achieve satisfactory results geometrically speaking, with an average standard deviation of 1.7 cm in interior cases where the scene dimension is roughly 25–50 m3 in volume. However, the level of noise on the point cloud, which was considered as out of tolerance, ranges between 17–42%, meaning that the level of detail and finesse is most likely insufficient for sophisticated heritage documentation purposes, even though from a visualisation point of view the results were better. However, NeRF did show the capability to reconstruct texture less and reflective surfaces where MVS failed. [ABSTRACT FROM AUTHOR]

The development of modern surveying methods, particularly, Terrestrial Laser Scanning (TLS), has found wide application in protecting and monitoring engineering and objects and sites of cultural heritage. For this reason, it is crucial that several factors a˛ecting the correctness of point cloud registration are considered, including the correctness of the distribution of control points (both signalised and natural), the quality of the process, and robustness analysis. The aim of this article is to evaluate the quality and correctness of TLS registration based on point clouds converted to raster form (in spherical mapping) and hand-crafted detectors. The expanded Structure-from-Motion (SfM) was used to detect the tie points for TLS registration and reliability assessment. The results demonstrated that affine detectors are useful in detecting a high number of key points (increased for point detectors by 8–12 times and for blob detectors by about 10–24 times), improving the quality and TLS registration completeness. For the registration accuracy of point cloud on signalised check points, the lower values can be noted for maximum RMSE errors for blob affine detectors than detectors and larger values for corner detectors and affine detectors (not more than 4 mm in the extreme cases, typically 2 mm). The commonly-applied target-based registration method yields similar results (di˛erences do not exceed – in extreme cases – 3.5 mm, typically less than 2 mm), proving that using affine detectors in the TLS registration process is and reasonable and can be recommended.

Kramers-Kronig analysis provides the means to study photoreflectance spectra of heavily doped GaAs/Si-GaAs structures. Using Kramers-Kronig analysis, a complex photoreflectance function is created. The function's modulus provides the critical point energy. The phase of the function is suitable for a topographical study of the homogenity of the structure'sinternal electric field.

An orthoimage is one of the basic photogrammetric products used for architectural documentation of historical objects; recently, it has become a standard in such work. Considering the increasing popularity of photogrammetric techniques applied in the cultural heritage domain, this research examines the two most popular measuring technologies: terrestrial laser scanning, and automatic processing of digital photographs. The basic objective of the performed works presented in this paper was to optimize the quality of generated high-resolution orthoimages using integration of data acquired by a Z+F 5006 terrestrial laser scanner and a Canon EOS 5D Mark II digital camera. The subject was one of the walls of the "Blue Chamber" of the Museum of King Jan III's Palace at Wilanów (Warsaw, Poland). The high-resolution images resulting from integration of the point clouds acquired by the different methods were analysed in detail with respect to geometric and radiometric correctness. [ABSTRACT FROM AUTHOR]

The article sets out to explore how conflicting institutional logics of support organizations influence their value creation. Value creation undertaken by support organizations does not directly reflect their missions. Even though one can generalize that all support organizations should adjust their offer according to the idea of helping companies (especially small- and medium-sized enterprises [SMEs]) in their development, support organizations very often struggle with the conflict between mission delivery and survival needs, which affects value proposition of services. Moreover, support organizations are also shaped by institutional logics, which, embedded in social systems, govern all social agents. Therefore, the study explains the challenge of value creation from the perspective of the conflict of competing institutional logics that govern support organizations. The study also has its academic impact by contributing to existing literature on value creation by support organizations through the use of institutional logic theory. To gain this knowledge, discourse analysis is utilized in the study.

Projection of a complicated geometry of industrial objects is the complex issue, which requires properly planned and prepared measurements. Such objects must be accurately inventoried, but their complicated nature often makes the access and the visibility of their entire surface very difficult. Documentation of measurements is often prepared in the form of sketches, plans or maps, which are amended with photographic documentation. The objective of this paper is to test the possibilities to apply laser scanning and the network of digital images for inventory and monitoring of technical conditions of industrial objects. Processing of a precise documentation acquired basing on terrestrial laser scanning data or dense points clouds generated from digital images still causes many difficulties and problems. Although data processing algorithms have been intensively developed with respect to generation of high resolution orthoimages or precise vector drawings, the existing problems are still connected with limitations related to imperfections of both techniques of measurements.