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Number of results: 11
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Abstract

The work deals with possibilities of using this specific material. It is focused on cast metal foams with a regular arrangement of internal cells and it refers to already used casting technologies – the production of metal foamswith the aid of sand cores. Metal foamsare used in many industries, such as: automotive, aerospace, construction, power engineering. They have unique propertiesand due to lower weight with sufficient strength and greater contact surface can be used, for example, for the conduction of heat. This article deals with the useof the metal foam as a heat exchanger. The efficiency of the heat exchanger depends on its shape and size and therefore the study is focused first on the optimization of the shape before the proper manufacture.

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Authors and Affiliations

F. Radkovský
M. Gebauer
V. Merta
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Abstract

Modern geological maps are 3D, or even 4D models representing the complex structure of the Earth. They interpret a variety of geological information and represent it in graphical form.
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Authors and Affiliations

Joanna Rychel
1
Łukasz Nowacki
1
Mirosław Kamiński
1

  1. Polish Geological Institute – National Research Institute in Warsaw
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Abstract

The radar method, executed with the use of ground penetrating radars - the georadars, belongs to non-intrusive methods of positioning subsurface structures and objects. The direct result of the survey is the so-called radargram - a radar image, that is a vertical cross-section of the penetrated medium. It brings an information on the existence and mutual position of ground layers and subsurface structures and objects. The radargram, as the direct result of measurement, demands further processing for its interpretation and use. The consecutive steps leading from a non-metric radargram to the metric 3D model, based on corresponding surveying and georadar data are presented. The paper concentrates on the problem of broadening the scope of interpretation and applications of georadar surveys thanks to proper integration of advanced filtering programs, graphical software and programs from the CAD and SIT environment. The aim of the integration is a metric 3D model of subsurface objects and structures located with the georadar method. The ways and stages of generation of the spatial subsurface models, presented in the paper, complement surveying sources of data for thematic maps.
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Authors and Affiliations

Jan Gocal
Łukasz Ortyl
Marian Sołtys
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Abstract

The paper presents a 3D model and simulations of corroding reinforcement bars in a concrete element. Electric potential distributions are calculated in the concrete matrix and on its surface for two rebars arrangements with one or three active (anodic) sites to assess the reliability and identify possible problems when standard test measurements for corrosion assessment in concrete structures are used and conclusion on the corrosion state is inferred. The values of the potential strongly depend on a concrete layer thickness and beyond the threshold of 5-7 cm it is hardly possible to detect the number of active sites on the rebar. Also conductivity – which is not constant in real world constructions – is an important factor. Thus without estimation of the state of concrete it is difficult to draw reliable conclusions on the corroding activity from shear potential measurements on the surface.

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Authors and Affiliations

R. Filipek
K. Szyszkiewicz-Warzecha
J. Szczudło
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Abstract

Quality of 3d model in simple way translates into quality of final product, obtained from 3d printing. 3d CAx software give possibility to create enormous number of shapes – doesn’t matter solids or surfaces. The question is where is the frontier between quality of 3d model and a value for money of the completed print? Is it always necessary to create as good model as possible? This paper will focus on preparation of 3d models, based on primitives and will show connection between quality of mesh, its size and deviations and quality of obtained samples, in same manufacturing conditions.
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Authors and Affiliations

M. Tagowski
1
ORCID: ORCID

  1. Częstochowa University of Technology, Faculty of Technology and Automation, 21. Armii Krajowej Av., 42-201 Częstochowa, Poland
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Abstract

The article describes the process of creating 3D models of architectural objects on the basis of video images, which had been acquired by a Sony NEX-VG10E fixed focal length video camera. It was assumed, that based on video and Terrestrial Laser Scanning data it is possible to develop 3D models of architectural objects. The acquisition of video data was preceded by the calibration of video camera. The process of creating 3D models from video data involves the following steps: video frames selection for the orientation process, orientation of video frames using points with known coordinates from Terrestrial Laser Scanning (TLS), generating a TIN model using automatic matching methods. The above objects have been measured with an impulse laser scanner, Leica ScanStation 2. Created 3D models of architectural objects were compared with 3D models of the same objects for which the self-calibration bundle adjustment process was performed. In this order a PhotoModeler Software was used. In order to assess the accuracy of the developed 3D models of architectural objects, points with known coordinates from Terrestrial Laser Scanning were used. To assess the accuracy a shortest distance method was used. Analysis of the accuracy showed that 3D models generated from video images differ by about 0.06 ÷ 0.13 m compared to TLS data.
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Authors and Affiliations

Paulina Deliś
Michał Kędzierski
Anna Fryśkowska
Michalina Wilińska
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Abstract

Terrestrial laser scanner (TLS) is a new class of survey instruments to capture spatial data developed rapidly. A perfect facility in the oil industry does not exist. As facilities age, oil and gas companies often need to revamp their plants to make sure the facilities still meet their specifications. Due to the complexity of an oil plant site, there are difficulties in revamping, having all dimensions and geometric properties, getting through narrow spaces between pipes and having the description label of each object within a facility site. So it is needed to develop an accurate observations technique to overcome these difficulties. TLS could be an unconventional solution as it accurately measures the coordinates identifying the position of each object within the oil plant and provide highly detailed 3D models. This paper investigates creating 3D model for Ras Gharib oil plant in Egypt and determining the geometric properties of oil plant equipment (tank, vessels, pipes . . . etc.) using TLS observations and modeling by CADWORX program. The modeling involves an analysis of several scans of the oil plant. All the processes to convert the observed points cloud into a 3D model are described. The geometric properties for tanks, vessels and pipes (radius, center coordinates, height and consequently oil volume) are also calculated and presented. The results provide a significant improvement in observing and modeling of an oil plant and prove that the TLS is the most effective choice for generating a representative 3D model required for oil plant revamping.

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Authors and Affiliations

Ahlam I. Elgndy
Zaki M. Zeidan
Ashraf A. Beshr
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Abstract

The aim of this research is to evaluate the performance of four UAV image processing software for the automatic estimation of volumes based on estimated volume accuracy, spatial accuracy, and execution time, with and without Ground Control Points (GCPs). A total of 52 images of a building were captured using a DJI Mavic Air UAV at 60m altitude and 80% forward and side overlap. The dataset was processed with and without GCPs using Pix4DMapper, Agisoft Metashape Pro, Reality Capture, and 3DF Zephyr. The UAV-based estimated volume generated from the software was compared with the true volume of the building generated from its as-built 3D building information modeled in Revit 2018 environment. The resulting percentage difference was computed. The average volumes estimated from the four software with the use of GCPs were 4757.448 m3 (3.87%), 4728.1 m3 (2.54%), 4291.561 m3 (11.5%), and 4154.938 m3 (14.35%), respectively. Similarly, when GCPs were not used for the image processing, average volumes of 4631.385 m3 (4.52%), 4773.025 m3 (1.6%), 4617.899 m3 (4.89%), and 4420.403 m3 (8.92%) were obtained in the same order. In addition to the volume estimation analysis, other parameters, including execution time, positional RMSE, and spatial resolution, were evaluated. Based on these parameters, Agisoft Metashape Pro proved to be more accurate, time-efficient, and reliable for volumetric estimations from UAV images compared to the other investigated software. The findings of this study can guide decision-making in selecting the appropriate software for UAV-based volume estimation in different applications.
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Authors and Affiliations

Oluibukun Gbenga Ajayi
1 2
ORCID: ORCID
Bolaji Saheed Ogundele
2
ORCID: ORCID
Gideon Abidemi Aleji
2
ORCID: ORCID

  1. Namibia University of Science and Technology, Windhoek, Namibia
  2. Federal University of Technology, Minna, Nigeria
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Abstract

Transmission lines’ live working is one of an effective means to ensure the reliable operation of transmission lines. In order to solve the unsafe problems existing in the implementation of traditional live working, the paper uses ground-based lidar to collect point cloud data. A tile based on the pyramid data structure is proposed to complete the storage and calling of point cloud data. The improved bidirectional filtering algorithm is used to distinguish surface features quickly and obtain a 3D model of the site. Considering the characteristics of live working, the speed of data reading and querying, the nearest point search algorithm based on octree is used to acquire a real- time calculation of the safe distance of each point in the planned path, and the safety of the operation mode is obtained by comparing with the value specified in the regulation, and assist in making decisions of the operation plan. In the paper, the simulation of the actual working condition is carried out by taking the “the electric lifting device ascending” as an example. The experimental results show that the established three-dimensional model can meet the whole process control of the operation, and has achieved practical effect.
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Authors and Affiliations

Ying Wang
1
ORCID: ORCID
Haitao Zhang
1 2 3
Qiang Lv
3
Qiang Gao
3
Mingxing Yi
3

  1. School of Automation & Electrical Engineering, Lanzhou Jiaotong University, Gansu, China
  2. Key Laboratory of Opto-Electronic Technology and Intelligent Control Ministry of Education, Lanzhou Jiaotong University Gansu, China
  3. The UHV Company of State Grid Gansu Electric Power Company, Gansu, China
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Abstract

Extremely intensive development of technology has resulted in many innovations. There are new methods of acquiring spatial data, such as laser scanning, unmanned aerial vehicles or digital non-metric cameras, which are the subject of this study. Integration of this data has become a new tool that has expanded existing measurement capabilities, finding applications in 3D modelling, archaeology and monument conservation. Owing to scanning, we can get the coordinates of almost every point of the scanned surface, obtaining full and detailed information about the object dimensions. The level of technical advancement of digital cameras allows them to be successfully used in short-range photogrammetry [27], and recently also in low-altitude aerial photogrammetry (unmanned aerial vehicles). Two different test objects were selected to achieve the intended purpose. The monument located on the 14-meter-high top of the Wanda Mound was adopted as the first object. It consists of a simple rectangular plinth made of brown marble. On its top there is a figure of an eagle with a crown of white marble. On the west wall of the plinth there is an inscription “Wanda” and a drawing showing a sword crossed with a distaff. The following features supported the choice of the monument: interesting shape of the object, which includes both simple geometric forms with large and flat surfaces (plinth), and more detailed surfaces (figure of an eagle); detailed texture of the object (complicated marble veins, wing details). The second object under study was The Helena Modrzejewska National Stary Theatre. The building was rebuilt in the style of Viennese Art Nouveau, so that it fully incorporates into the rest of buildings. Measurements included data obtained from a non-metric camera, Leica ScanStation scanner and DJI S 1000 multi-rotor.
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Authors and Affiliations

Izabela Piech
1
ORCID: ORCID
Tomasz Adam
2
Paulina Dudas
2

  1. Krakow University of Agriculture, Faculty of Environmental Engineering and Land Surveying, Al. Mickiewicza 24/28, 30-059 Krakow, Poland
  2. Graduate of the University of Agriculture in Krakow, Faculty of Environmental Engineering and Land Surveying, Al.Mickiewicza 24/28, 30-059 Krakow, Poland
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Abstract

The article presents the approach to the design process of acoustic panels based on the scientific research. This approach is based on combining the technical and the design competences to develop the innovative product value for the concept of acoustic panels. The article presents the concepts of two new acoustic panels – an absorbing and scattering panel and a panel reflecting sound waves. The first part of the article presents the starting point for the presented project – the acoustic research and the inspiration for both types of presented solutions. Next, the materials possible to use were discussed, which could reproduce the natural acoustic properties of the lava and glacier caves. The next part presents consecutive stages of the product development in a modern form, ensuring the expected acoustic properties. The last part of the article presents a fully functional solution and proposes further research and development directions.
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Authors and Affiliations

Bartłomiej Borkowski
1
Katarzyna Suder-Dębska
2
Jerzy Wiciak
1
Anna Maria Szlachta
3

  1. Department of Mechanics and Vibroacoustics, AGH – University of Science and Technology, Kraków, Poland
  2. Department of Power Systems and Environmental Protection Facilities, AGH – University of Science and Technology, Kraków, Poland
  3. Faculty of Industrial Design, Jan Matejko Academy of Fine Arts, Kraków, Poland

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