Terrain modeling for real-time photo-texture based visual simulation

The usage of realistic three-dimensional (3D) polygon terrain models with multiple levels of detail (LOD) is becoming widespread in popular applications like computer games or simulations, as it offers many advantages. These models, which represent an actual location in the world, are essential for the simulation-based training of military vehicles like planes, helicopters or tanks. Because training scenarios on this kind of simulations are used to observe or to hit a target on the modeled location. In addition to that, driving the behavior of terrestrial vehicles is influenced by the terrain properties like slopes, ramps, hitches, etc. because of the direct interaction with the ground. For this reason, the terrain models in the simulation scene should not only display the textures realistically, but also represent an accurate morphology; meaning the terrain altitudes should be modeled as correct as possible. Such terrain representations can be created by using Digital Terrain Model (DTM) for the geometry and satellite images for texturing. The geometry models are in the form of polygonal meshes through the triangulation methods. However, the accuracy is influenced by some parameters. Using insufficient (under-refined) triangles during the 3D modeling causes missing of some altitude vertices. That means these points will not be present in the model. Consequently, it can be thought that the number of triangles should be increased for a better geometrical fidelity. Nevertheless, it is not always correct as the usage of too much (over-refined) triangles can also cause errors, especially in terrains with almost vertical faces (like cliffs). In addition to that, the performance of the system deteriorates drastically through the increase in the number of triangles, as the computational complexity is also getting higher.

In this paper, a new seamless and adaptive LOD (Level of Details) modelling method of global terrain based on the QTM (Quaternary Triangular Mesh) is described. Our approach starts with QTM tessellation based on the WGS84 ellipsoidal surface. Thus, the global terrain can be represented by an array of elevation values of QTM vertices. Next, an adaptive idea of a Binary Triangle Tree is inserted in this QTM model to form an adaptive, continuous, and uniform LOD triangular mesh in the DEM grids and their vertices completely coincide with the vertices of QTM. The experiment and analysis are carried out with the global terrain data, GTOPO30. The results illustrate that: (1) the global DEM model based on QTM is seamless, hierarchical, and regular over the whole Earth, and the dataset occupies only about half of its initial size; (2) an adaptive LOD (Level of Details) model of the DEM data blocks is constructed and the problem of discontinuity in different subdivision levels is overcome; and (3) the number of the triangles in this adaptive LOD model decreases greatly as their error tolerances increase, but there is no obvious change in the results

This thesis contains a set of contributions that focuses on challenges in visualization of polygon models of trees, in particular models of tree stems and branches. These challenges cover a wide range of the visualization research field, including generation of polygon models of trees, hardware accelerated visualization and animation of trees from parametric systems, and surface modelling and tessellation for tree stems. To generate polygon models of trees, an existing approach for automatically generating polygon models of branching vascular transportation systems, typically blood vessels, is extended to handle tree stems. The approach allowed for automation of the generation process, while maintaining smoothness at branching areas. The approach is used to generate polygon models of trees. For hardware accelerated visualization and animation of trees from parametric systems, methods for visualization of trees described by parametric descriptions are adapted and extended to run on dedicated graphic processing hardware. To allow for animation of trees visualized in such a manner, an animation process that is hardware accelerated is developed using knowledge gained from work on hardware acceleration approaches in the field of image processing. For surface modelling and tessellation for visualization of trees, concepts, ideas and early work are presented. The basic concept is that by working with a coarse polygon model of a tree during animation (or by generating a coarse polygon model of a tree after animation is done); one can tessellate this coarse model in hardware in real-time to a much higher degree then earlier approaches. This will then enable one to visualize trees stems of a higher Level of Detail (LOD) and at higher speeds than were previously achievable. Although the contributions in this thesis cover a wide range of challenges from the visualization research field, the main focus has been on generation, animation and visualization of tree stems and branches for use in real-time applications. Especially the concept of hardware acceleration has become more of a focus, as graphic processing hardware has become more and more powerful both in speed and especially in functionality. The contributions will hopefully help in future development of even better methods for visualizing trees and plants.

This paper presents a new distributed method for virtual Earth terrain tessellation on a graphics processing unit (GPU) for space simulator complexes. The method operates in real time in multi-object virtual scenes comprising up to two million polygons. A polygonal terrain model is constructed using triangle patches of different levels of detail on graphics cards with programmable tessellation. Patches of the same level of detail are calculated entirely on the GPU, in parallel and independently, by using a developed shader program written in the OpenGL Shading Language (GLSL). This paper also describes a patch extraction algorithm for visible Earth surface rendering and an algorithm for correcting the barycentric coordinates of tessellated patch vertices that allows triangles in the terrain model to be docked without geometric discontinuities. Based on the distributed methods and algorithms developed, a program complex for virtual Earth surface visualization was created and successfully tested. The proposed solution can also be employed in virtual environment systems, virtual labs, educational geo-applications, etc.

For land planning or visualization, there is a need to model a large area of digital terrain in a graphics workstation and then display the 3D terrain model at a general frame rate. However, the geometrical complexity of terrain models far exceeds the capabilities of a general graphics workstation. Using a multi-resolution terrain model is one way to fit the requirement of the applications. Simplification or decimation algorithms are used to generate multiple terrain models at different detailed levels and then the models are selected to display for different situations such as distance or view scope. In this study, the authors concentrate on the triangulation and the level-of-detail generation of terrain models. In triangulation, they improve the performance of Palacios-and-Renuad triangulation algorithm. In level-of-detail generation, they give a new criterion to improve the accuracy of sequential multi-resolution terrain models based on the Schroder-and-Robbach, Schroeder et. al., and Floriani-and-Puppo approaches. They also propose a new hierarchical structure of Delaunay triangulated models to represent multi-resolution terrain models. The hierarchical structure is a tree structure, and thus result in a better search performance than other approaches.

In 3D entertainment oriented games, most geometrical objects are represented by polygon sets. Thus, the handling of polygons is highly optimized in the hardware of graphic workstations. However, 3D scientific simulations do not ordinarily use polygon data but rather volume data in its original form, such as the scalar array p(x,y,z). If we had an effective volume data compression algorithm and a standard way of representing this data, it could be used in a more efficient manner in the network environment. This paper presents a Smoothed Particle Transformation (SPT) algorithm for volume data at several levels of compressed resolution from an original array description of a given variable. Representing data at various levels of detail is important for archiving the huge data in the network environment. SPT contributes not only to data compression but also for resolution rearrangement. As a result, it speeds up of the visualization of transferred data, especially for the direct volume rendering of compressed data.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Resource efficiency has always been a hot topic for the steel industry, due to the large amounts of primary raw materials, by products and water, which are handled in the steelmaking cycle as well as the considerable energy consumptions. The ever more stringent environmental regulations also contribute to pressurize the iron and steel industry to strengthen further its research activities fostering an optimal management and exploitation of resources. Thus important research efforts are spent in order to find the best way to recover wastes and wastewater also involving the implementation of retrofit actions and major plant modifications allowing also the reduction of primary raw material consumption and of waste disposal. In order to achieve such ambitious objective, which implies both environmental benefits and cost savings, process integration is a powerful tool. The assessment of the viability of process integration solution necessarily include a final experimental stage to be performed at plant level, which can be expensive or unsafe. To this aim process simulation can be a useful alternative to accomplish preliminary feasibility studies allowing a deep analysis of all the aspect of a particular technology or retrofit actions, which also allows testing conditions that are very difficult to replicate within practical experiments. Different levels of detail can be achieved and a comprehensive analysis can be carried out. The present paper provides an overview of the simulation techniques exploited during the project entitled Efficient Use of Resources in Steel Plants through Process Integration to the aim of optimizing the use of resources in an Italian integrated steelmaking plant. In particular, different case studies are proposed and the obtained meaningful and practical results are presented and discussed.

Next-generation digital broadcasting system transmits the DASH segment files. Delays and inefficient use of resources are the major challenges in the transmission of DASH segment files in broadcasting systems. Because the size of DASH segment files varies even though the files have the same quality, and broadcasting systems uses the fixed resource. Delay is an important problem in broadcasting systems because these are real-time systems. Therefore, next-generation digital broadcasting systems should minimize delays and use resource efficiently. This paper proposes a transmission model that can analyze delays as well as efficient use of resources.

This paper aims to provide a robust solution to mitigate the adverse effects of climate change and inefficient use of resources in Pakistan, one of the most vulnerable countries to global warming. The key problems that are aimed to resolve are, firstly, the food insecurity in Pakistan due to the decrease of cultivable land against a sharp rise in population, secondly, water scarcity due to inefficient use of water resources, particularly, in the agricultural sector and, lastly, irregularities in the environmental conditions resulting in stunted yield in arable areas. To overcome this, the proposed solution is a Grow Box based on hydroponics-based farming; a portable controlled environment allowing soilless gardening by implementing the Aeroponics method. The design of the grow box is such that it would monitor the many parameters crucial for farming such as the water quality, humidity, and temperature by the implementation of WSN (Wireless Sensor Network) and IoT (Internet of things) to ensure maximum yield of best quality plants in the limits of the grow box. The final product monitors the environmental parameters of the inert grow box via a developed WSN. The integration of IoT to let connection to the internet, allows remote streaming, and the mechanical design of the grow box are also completed and showcased in the paper.

Programmers often use informal worst-case analysis and debugging to ensure that schedulers satisfy real-time requirements. Not only can this process be tedious and error-prone, it is inherently conservative and thus likely to lead to an inefficient use of resources. We propose to use model checking to find a schedule which optimizes the use of resources while satisfying real-time requirements. Specifically, we represent a Wireless sensor and actuator network (WSAN) as a collection of actors whose behaviors are specified using a Java-based actor language extended with operators for real-time scheduling and delay representation. We show how the abstraction mechanism and the compositionality of actors in the actor model may be used to incrementally build a model of a WSAN's behavior from node-level and network models. We demonstrate the approach with a case study of a distributed real-time data acquisition system for high-frequency sensing using Timed Rebeca modeling language and the Afra model checking tool.

The unfolding of a full-scale war on the territory of Ukraine, which led to immediate changes in the demographic situation of the state and the loss of a significant part of its human potential, also had devastating consequences for the economy, which will be felt for a long time. Therefore, it is necessary to search for various levers of economic growth and preservation of human capital, which today should become a priority task of the state on the way out of the economic and demographic crisis, and the possibilities of its integration into the European and world economy. In Ukraine, low labor productivity is one of the defining problems hindering the development of its economy, along with the issues of inefficient use of labor resources and the policy of remuneration. The problem lies not only in the low level of labor productivity but also in the rather low growth rates of this indicator. The article assesses disparities in labor productivity levels across regions of Ukraine. The study shows that low labor productivity is one of the defining problems inhibiting the development of the economy of Ukraine, along with the issues of inefficient use of labor resources and labor remuneration policy. The authors emphasize that the problem lies not only in the low level of labor productivity but also in the low growth rates of this indicator. The dynamics of GRP and the employed population in 2014-2020 is calculated, and the regions are ranked by the level of employment concentration. A comparative analysis of the levels of employment concentration during the research period is carried out and changes in regional employment disparities are revealed. Based on the analysis of employment indicators and GRP. The article identifies the regions demonstrating the efficiency of the use of labor resources in Ukraine. The predominance of regions in the country with inefficient use of labor resources is revealed. The most important reasons for maintaining a low level of labor productivity in Ukraine and its regions are substantiated, and relevant recommendations for solving these problems are proposed.

Using Material Flow Analysis for Sustainable Materials Management

Visualization of large geometric environments has always been an important problem of computer graphics. We present a framework for the stereoscopic view-dependent visualization of large scale terrain models. We use a quadtree based multiresolution representation for the terrain data. This structure is queried to obtain the view-dependent approximations of the terrain model at different levels of detail. In order not to lose depth information, which is crucial for the stereoscopic visualization, we make use of a different simplification criterion, namely, distance-based angular error threshold. We also present an algorithm for the construction of stereo pairs in order to speed up the view-dependent stereoscopic visualization. The approach we use is the simultaneous generation of the triangles for two stereo images using a single draw-list so that the view frustum culling and vertex activation is done only once for each frame. The cracking problem is solved using the dependency information stored for each vertex. We eliminate the popping artifacts that can occur while switching between different resolutions of the data using morphing. We implemented the proposed algorithms on personal computers and graphics workstations. Performance experiments show that the second eye image can be produced approximately 45 percent faster than drawing the two images separately and a smooth stereoscopic visualization can be achieved at interactive frame rates using continuous multiresolution representation of height fields.

Corruption risks in the energy industry can lead to inefficient use of resources, delays in project implementation, and worsening environmental conditions. Therefore, for a successful energy transition, it is crucial to implement anti-corruption practices and ensure a high degree of transparency in energy resource management. This article addresses the challenges of combating corruption in the Russian energy industry amid globalization and changes in the economic landscape. It explores the difficulties faced by energy companies operating in environments with high corruption levels, such as inefficient resource use, delays in project timelines, and environmental degradation. The article emphasizes the importance of adopting anti-corruption practices and ensuring transparency in energy resource management to achieve a successful energy transition and sustainable development. Drawing on international experience, recommendations are provided for introducing transparent tendering procedures, encouraging active citizen participation in oversight, and other measures. In conclusion, the article stresses the need for a comprehensive approach to fighting corruption, including improving legislation and fostering ethical reforms in management

This paper addresses the relevance of the notion of sustainable development in a regional context and the use of models for regional sustainable development policy. First, the notion of sustainable development is discussed by linking socio-economic and ecological elements. In a spatial context an often neglected but relevant concept is regional sustainable development (RSD). Its relationship with both the global concept of sustainable development and sustainable use of resources is discussed. The use of models for sustainable development in a regional context is investigated. All potential models integrate economy and ecology: a description of economic processes, ecological processes and their interactions; and an inclusion of socio-economic and ecological indicators in the policy evaluation. Only dynamic models are considered, as they are regarded to be the most relevant class for addressing issues of sustainable development. It is argued that scenario and simulation models are most appropriate on a regional level, as here the level of detail in describing the economics and ecology is fairly balanced. Finally, a case study is presented for the Peel region, an area in the Netherlands, where presently agriculture causes considerable damage to groundwater, forests, and protected fen areas due to intensive cattle farming, irrigation and drainage. Several relevant development scenarios for RSD planning are developed, and the model analyses for each of them are reviewed from the viewpoint of RSD.