HYPSOMETRY AND VOLUMETRY OF Eucalyptus urograndis IN A CROP-FOREST INTEGRATION SYSTEM

Due to the positive impact that the eucalyptus species has on the Brazilian economy, it is currently the most used forest essence. The objective of this work was to evaluate different hypsometric and volumetric models for Eucalyptus urograndis clones (Eucalyptus urophylla S.T. Blak and Eucalyptus grandis W. Hill ex Maiden) in a Crop-Forest Integration (CFI) system. The trees were evaluated at 7 years of age and arranged in double rows, occupying 20.76% of the total system area. The individuals were subjected to rigorous volumetric cubing according to the Smalian method at intervals of one meter up to full height. The following models were evaluated for the collected height data: Linear, Trorey, Stofels, Curtis, Henriksen, Prodan, Chapman & Richards, Petterson and Bailey & Clutter. Furthermore, the Spurr, Hohenald-Krenn, Stoate, Schumacher Hall, Meyer, Husch, Ogaya and Takata models were used for volume data. The results were determined through the coefficient of determination (R2), standard error of the estimate in percentage (Syx%), significance of the regression coefficients (𝛽) and graphical distribution. The hypsometric model which best fit the database among tested models was the Prodan equation, with a coefficient of determination (R²) of 0.89, while the best result for volumetric models was found using the Meyer model, with a coefficient of determination (R²) of 0.99. All evaluated models were efficient in estimating the height and volume of the Crop-Forest Integration (CFI) system, thus demonstrating that GG100 eucalyptus is a good option in integrated systems.

Compositional study of the lost temples in instructional design

The article presents the design and research work of the authors and first-year architecture students of Irkutsk National Research Technical University concerning compositional study of lost temples of Irkutsk with the reconstruction of their architectural appearance. The illustrative material was prepared using the students’ works. The complex of Siberian Baroque temples in Irkutsk in the mid-18th – late 19th centuries and various types of church buildings were studied. The work uses modeling as a tool for predicting the architectural appearance of the temple. Sketch drawings and models of the Miracle-Working, Tikhvinsky and Annunciation temples were completed, and the model of the evolution of Siberian Baroque temples was recreated. The main stages of the term project, from building functional, planning and volumetric models to designing image and structural characteristics of the object on the sample board, were presented.

COMPUTING WATERTIGHT VOLUMETRIC MODELS FROM BOUNDARY REPRESENTATIONS TO ENSURE CONSISTENT TOPOLOGICAL OPERATIONS

To simulate environmental processes, noise, flooding in cities as well as the behaviour of buildings and infrastructure, ‘watertight’ volumetric models are a measuring prerequisite. They ensure topologically consistent 3D models and allow the definition of proper topological operations. However, in many existing city or other geo-information models, topologically unchecked boundary representations are used to store spatial entities. In order to obtain consistent topological models, including their ‘fillings’, in this paper, a triangulation combined with overlay and path-finding methods is presented by climbing up the dimension, beginning with the wireframe model. The algorithms developed for this task are presented, whereby using the philosophy of graph databases and the Property Graph Model. Examples to illustrate the algorithms are given, and experiments are performed on a data-set from Erfurt, Thuringia (Germany), providing complex geometries of buildings. The heavy influence of double precision arithmetic on the results, in particular the positional and angular precision, is discussed in the end.

A Voxel-Based Watermarking Scheme for Additive Manufacturing

Digital and analog contents, generated in additive manufacturing (AM) processes, may be illegally modified, distributed, and reproduced. In this article, we propose a watermarking scheme to enhance the security of AM. Compared with conventional watermarking methods, our algorithm possesses the following advantages. First, it protects geometric models and printed parts as well as G-code programs. Secondly, it embeds watermarks into both polygonal and volumetric models. Thirdly, our method is capable of creating watermarks inside the interiors and on the surfaces of complex models. Fourth, the watermarks may appear in various forms, including character strings, cavities, embossed bumps, and engraved textures. The proposed watermarking method is composed of the following steps. At first, the input geometric model is converted into a distance field. Then, the watermark is inserted into a region of interest by using self-organizing mapping. Finally, the watermarked model is converted into a G-code program by using a specialized slicer. Several robust methods are also developed to authenticate digital models, G-code programs, and physical parts. These methods perform virtual manufacturing, volume rendering, and image processing to extract watermarks from these contents at first. Then, they employ similarity evaluation and visual comparison to verify the extracted signatures. Some experiments had been conducted to validify the proposed watermarking method. The test results, analysis, discussion, and comparisons are also presented in this article.

WOOD VOLUMETRY OF Tachigali vulgaris PURE PLANTATIONS IN DIFFERENT PLANTING SPACINGS

The aim of this study was to develop volumetric equations for tachi-branco trees (Tachigali vulgaris L. G. Silva & H. C. Lima), by assessing the effect of initial planting spacing in volume estimates, as well as developing an equation to estimate the equivalent diameter (deq). Data are from an experiment located in north Pará. The experiment was conducted with the randomized blocks design, being three blocks with six treatments each. The most used volumetric models were assessed for two distinct situations: considering each trunk as a tree and using the tree deq as independent variables in the volumetric model. The need for individual equations for initial planting spacing was tested. In addition, an equation for deq estimate was proposed. The use of deq provided more precise and accurate volumetric estimates regarding diameter at breast height. Among the models tested, the Schumacher-Hall model was selected. Through the model identity test, the equation can be used to estimate tree volume of Tachigali vulgaris, regardless of planting spacing. The equivalent diameter can be estimated via equation from minimum and maximum diameters of tree trunks. The maximum percentage differences of volume by hectare obtained with the measurement of all trunks and deq were only 5% without loss in production accuracy per unit of area

Exploring and illustrating the mouse embryo: virtual objects to think and create with

The teaching, learning, communication, and practice of Developmental Biology require interested parties to be at ease with the considerable spatial complexity of the embryo, and with its evolution over time as it undergoes morphogenesis. In practice, the four dimensionality of embryonic development (space and time) calls upon strong visual-spatial literacy and mental manipulation skills, generally expected to be innate or to come through experience. Yet it has been argued that Developmental Biology suffers the most from available traditional media of communication and representation. To date, few resources exist to engage with the embryo in its 3D and 4D aspects, to communicate such aspects in one’s work, and to facilitate their exploration in the absence of live observations. I here provide a collection of readily-usable volumetric models for all tissues and stages of mouse peri-implantation development as extracted from the eMouse Atlas Project (E5.0 to E9.0), as well as custom-made models of all pre-implantation stages (E0 to E4.0). These models have been converted to a commonly used 3D format (.stl), and are provided in ready-made files for digital exploration and illustration. Further provided is a step-by-step walkthrough on how to practically use these models for exploration and illustration using the free and open source 3D creation suite Blender. I finally outline possible further uses of these very models in outreach initiatives of varying levels, virtual and augmented reality applications, and 3D printing.