Development of a method for improving the accuracy of measurement of linear measures of 3D models via scanning

The object of research is to refine the linear sizes of the obtained 3D models via scanning, and reducing the numbers of errors when obtaining the model. For now, there is no accuracy method for transferring the actual sizes of an object to a 3D model. One of the most problematic places in the existing methods of transferring sizes from the object to the model is the error in the placement of dimensional markers due to inaccuracy, or poor quality of the received surface via scanning. A model of the instrument complex is used to implement an improved method of 3D scanning, based on the photogrammetric method. The advanced technology of construction and measurement of 3D models on the basis of photos on the principle of stereo pairs in combination with image projection is based on a combination of existing scanning methods. As well as the introduction of new functionalities, such as maintaining the actual sizes of an object, its textures, color and light characteristics, as well as improving the accuracy of linear sizes. As a result of the use of a standard, reference projections, and a new method of comparing photographs to build a 3D model, a 60 % increase in the accuracy of linear dimensions was achieved. This is due to the fact that the proposed new combined method incorporates all the existing most important aspects of scanning. And also has a number of features, such as the definition of boundary surfaces, automatic sizing, detection, and processing of glass and mirror surfaces. Due to this, this method eliminates the main disadvantages of the usual photogrammetric method – inaccuracies in the surface quality of the models, and inaccuracies in the transfer of linear dimensions. It is estimated that the combined method will allow to transfer the real size of simple objects in 3D with an accuracy of 99.97 % of the actual size of the object. It will also improve the quality of complex surfaces (boundary, glass, mirror) by at least 40–60 %, compared to other existing methods.

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A redesign of OGC Symbology Encoding standard for sharing cartography

10.7287/peerj.preprints.2415v4 ◽

2017 ◽

Author(s):

Erwan Bocher ◽

Olivier Ertz

Keyword(s):

Spatial Data ◽

Poor Quality ◽

Use Cases ◽

General Observation ◽

Data Infrastructures ◽

Open Standards ◽

Definition Of ◽

Data Requirements ◽

Basic Level

Despite most Spatial Data Infrastructures are offering service-based visualization of geospatial data, requirements are often at a very basic level leading to poor quality of maps. This is a general observation for any geospatial architecture as soon as open standards as those of the Open Geospatial Consortium (OGC) shall be applied. To improve the situation, this paper does focus on improvements at the portrayal interoperability side by considering standardization aspects. We propose two major redesign recommendations. First to consolidate the cartographic theory at the core of the OGC Symbology Encoding standard. Secondly to build the standard in a modular way so as to be ready to be extended with upcoming future cartographic requirements. Thus, we start by defining portrayal interoperability by means of typical use cases that frame the concept of sharing cartography. Then we bring to light the strengths and limits of the relevant open standards to consider in this context. Finally we propose a set of recommendations to overcome the limits so as to make these use cases a true reality. Even if the definition of a cartographic-oriented standard is not able to act as a complete cartographic design framework by itself, we argue that pushing forward the standardization work dedicated to cartography is a way to share and disseminate good practices and finally to improve the quality of the visualizations.

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Cancer Cachexia: Mechanisms and Clinical Implications

Gastroenterology Research and Practice ◽

10.1155/2011/601434 ◽

2011 ◽

Vol 2011 ◽

pp. 1-13 ◽

Cited By ~ 113

Author(s):

Claire L. Donohoe ◽

Aoife M. Ryan ◽

John V. Reynolds

Keyword(s):

Host Response ◽

Cancer Cachexia ◽

Resting Energy Expenditure ◽

Poor Quality ◽

Therapeutic Agents ◽

Progressive Weight Loss ◽

Slow Progress ◽

Definition Of ◽

The Relationship

Cachexia is a multifactorial process of skeletal muscle and adipose tissue atrophy resulting in progressive weight loss. It is associated with poor quality of life, poor physical function, and poor prognosis in cancer patients. It involves multiple pathways: procachectic and proinflammatory signals from tumour cells, systemic inflammation in the host, and widespread metabolic changes (increased resting energy expenditure and alterations in metabolism of protein, fat, and carbohydrate). Whether it is primarily driven by the tumour or as a result of the host response to the tumour has yet to be fully elucidated. Cachexia is compounded by anorexia and the relationship between these two entities has not been clarified fully. Inconsistencies in the definition of cachexia have limited the epidemiological characterisation of the condition and there has been slow progress in identifying therapeutic agents and trialling them in the clinical setting. Understanding the complex interplay of tumour and host factors will uncover new therapeutic targets.

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A redesign of OGC Symbology Encoding standard for sharing cartography

10.7287/peerj.preprints.2415v2 ◽

2017 ◽

Author(s):

Erwan Bocher ◽

Olivier Ertz

Keyword(s):

Spatial Data ◽

Poor Quality ◽

Use Cases ◽

General Observation ◽

Data Infrastructures ◽

Open Standards ◽

Definition Of ◽

Data Requirements ◽

Basic Level

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Problems of Creation and Usage of 3D Model of Structures and Theirs Possible Solution

Symmetry ◽

10.3390/sym12010181 ◽

2020 ◽

Vol 12 (1) ◽

pp. 181 ◽

Cited By ~ 2

Author(s):

Dalibor Bartonek ◽

Michal Buday

Keyword(s):

Computer Aided Design ◽

3D Model ◽

Three Dimensional ◽

3D Models ◽

Cad System ◽

Building Models ◽

Special Cad ◽

Aided Design ◽

The Church

This article describes problems that occur when creating three-dimensional (3D) building models. The first problem is geometric accuracy; the next is the quality of visualization of the resulting model. The main cause of this situation is that current Computer-Aided Design (CAD) software does not have sufficient means to precision mapping the measured data of a given object in field. Therefore the process of 3D model creation is mainly a relatively high proportion of manual work when connecting individual points, approximating curves and surfaces, or laying textures on surfaces. In some cases, it is necessary to generalize the model in the CAD system, which degrades the accuracy and quality of field data. The article analyzes these problems and then recommends several variants for their solution. There are described two basic methods: using topological codes in the list of coordinates points and creating new special CAD features while using Python scripts. These problems are demonstrated on examples of 3D models in practice. These are mainly historical buildings in different locations and different designs (brick or wooden structures). These are four sacral buildings in the Czech Republic (CR): the church of saints Johns of Brno-Bystrc, the Church of St. Paraskiva in Blansko, further the Strejc’s Church in Židlochovice, and Church of St. Peter in Alcantara in Karviná city. All of the buildings were geodetically surveyed by terrestrial method while using total station. The 3D model was created in both cases in the program AUTOCAD v. 18 and MicroStation.

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Production and production over-supply in construction: estimating unsold stock in Italy

International Journal of Housing Markets and Analysis ◽

10.1108/ijhma-07-2013-0042 ◽

2014 ◽

Vol 7 (4) ◽

pp. 506-523 ◽

Cited By ~ 2

Author(s):

Andrea Ciaramella ◽

Alberto Celani

Keyword(s):

Real Estate ◽

Poor Quality ◽

Real Estate Market ◽

Content Type ◽

The Real Estate ◽

Real Estate Sector ◽

Critical Issues ◽

Definition Of

Purpose – The aim of the article is to identify the limitations and critical issues in the way information in the real estate sector in Italy is currently managed, and propose the principles of a method that would provide information and comparison of the phenomenon of over-supply and non-rational land use. This study is based on a series of assumptions, the first of which is a definition of “unsold”, deemed to mean “the amount of new housing units neither occupied nor sold nor rented”. In effect, unsold stock can be considered as over-supply of construction. Design/methodology/approach – The article identifies the critical aspects in the determination of unsold real estate in Italy, starting from the available data and research already carried out; the results are often contradictory. The comparison with programming systems of building production adopted in other countries allows identification of the guidelines that can be used to better understand and combat the phenomenon. Findings – The assessment of the state -of-the-art provides a clear picture of the shortcomings and potential of the tools used to date to meet the need of studying a complex phenomenon with many obscure points. Following the empirical analysis comes out a picture of inefficiencies due to the poor quality of information, as well as the reluctance of data-sharing and -integration procedures by the institutional and market players. Research limitations/implications – The research produces solutions addressed to the Italian situation, but it identifies systems and methods used in other countries. Practical implications – The article suggests the collection systems and management information that can be used for a more accurate knowledge of unsold real estate. Social implications – The article focuses on some of the limits of the Italian real estate market, highlighting the need for greater transparency and how this can contribute to a more conscious approach to the market. Originality/value – The article seeks to provide the necessary answers to those who must understand the reasons of harmful effects for the market, such as overproduction; besides some models focused on three areas – the procedures, the organization and the market – are also proposed.

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The problem of ambiguity in the task of synthesizing a wireframe model objects according to a technical drawing

10.30987/graphicon-2019-1-201-204 ◽

2019 ◽

Author(s):

Валерия Тюрина ◽

Valeriya Tyurina ◽

Сергей Ротков ◽

Sergey Rotkov ◽

Татьяна Мошкова ◽

...

Keyword(s):

3D Model ◽

Complete Information ◽

3D Models ◽

Standard Procedures ◽

Technical Drawing ◽

Graphic Information ◽

Automatic Reading ◽

Geometric Elements ◽

Wireframe Model

The level of quality of the wireframe model obtained in the first stage of solving the problem of restoring the image of a non-planar object depends on the completeness of using the classes of graphic information used to synthesize a 3D model according to the technical drawing. In cases where the drawing is quite simple and allows you to read complete information about the object by existing procedures of automatic "reading the drawing", it is possible to restore the frame models that are fully consistent with the synthesized object. They can be used immediately for further transformations to other types of 3D models. Such frame models are characterized by the fact that all the vertices and edges included in their structure belong to the surface of the desired object. But in most practical cases, when the simulated objects correspond to real products and their technical drawing is full of difficult to formalize information, in the structure of frame models built according to standard procedures, due to a number of objective reasons, there are false geometric elements, i.e. those that are not on the surface of the desired 3D object. This leads to the ambiguity of the restoration of a unique wireframe model corresponding to the object specified in the technical drawing, and requires the development of procedures to avoid the multiplicity of solutions.

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Accuracy analysis of 3D model obtained by photogrammetric method on the example of historic room from Wisłoujście Fortress

E3S Web of Conferences ◽

10.1051/e3sconf/20186300013 ◽

2018 ◽

Vol 63 ◽

pp. 00013

Author(s):

Tadeusz Widerski ◽

Karol Daliga

Keyword(s):

Test Object ◽

3D Model ◽

3D Models ◽

Reference Points ◽

Control Points ◽

Accuracy Analysis ◽

Total Station ◽

Close Range Photogrammetry ◽

Close Range ◽

Photogrammetric Method

The article presents a comparison of obtained models of a test object. Close range photogrammetry was used to obtain 3D models. As test object was used one of the rooms located in Wisłoujście Fortress in Gdańsk, Poland. Different models were obtained by using different distribution and number of reference points. Article contains analysis of differences between coordinates of control points obtained from total station measurements and estimated from different 3D models.

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Information Recall in Pre-Operative Consultation for Glioma Surgery Using Actual Size Three-Dimensional Models

Journal of Clinical Medicine ◽

10.3390/jcm9113660 ◽

2020 ◽

Vol 9 (11) ◽

pp. 3660

Author(s):

Sümeyye Sezer ◽

Vitoria Piai ◽

Roy P.C. Kessels ◽

Mark ter Laan

Keyword(s):

3D Model ◽

Three Dimensional ◽

3D Models ◽

Patient Specific ◽

Mr Images ◽

Glioma Surgery ◽

Information Recall ◽

Cohen’S D ◽

Real Size ◽

Cohen's D

Three-dimensional (3D) technologies are being used for patient education. For glioma, a personalized 3D model can show the patient specific tumor and eloquent areas. We aim to compare the amount of information that is understood and can be recalled after a pre-operative consult using a 3D model (physically printed or in Augmented Reality (AR)) versus two-dimensional (2D) MR images. In this explorative study, healthy individuals were eligible to participate. Sixty-one participants were enrolled and assigned to either the 2D (MRI/fMRI), 3D (physical 3D model) or AR groups. After undergoing a mock pre-operative consultation for low-grade glioma surgery, participants completed two assessments (one week apart) testing information recall using a standardized questionnaire. The 3D group obtained the highest recall scores on both assessments (Cohen’s d = 1.76 and Cohen’s d = 0.94, respectively, compared to 2D), followed by AR and 2D, respectively. Thus, real-size 3D models appear to improve information recall as compared to MR images in a pre-operative consultation for glioma cases. Future clinical studies should measure the efficacy of using real-size 3D models in actual neurosurgery patients.

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Homomorphic Encryption-Based Robust Reversible Watermarking for 3D Model

Symmetry ◽

10.3390/sym12030347 ◽

2020 ◽

Vol 12 (3) ◽

pp. 347 ◽

Cited By ~ 2

Author(s):

Li Li ◽

Shengxian Wang ◽

Shanqing Zhang ◽

Ting Luo ◽

Ching-Chun Chang

Keyword(s):

3D Model ◽

Homomorphic Encryption ◽

Three Dimensional ◽

3D Models ◽

Reversible Watermarking ◽

Histogram Shifting ◽

Watermark Embedding ◽

Paillier Cryptosystem ◽

Embed Watermark

Robust reversible watermarking in an encrypted domain is a technique that preserves privacy and protects copyright for multimedia transmission in the cloud. In general, most models of buildings and medical organs are constructed by three-dimensional (3D) models. A 3D model shared through the internet can be easily modified by an unauthorized user, and in order to protect the security of 3D models, a robust reversible 3D models watermarking method based on homomorphic encryption is necessary. In the proposed method, a 3D model is divided into non-overlapping patches, and the vertex in each patch is encrypted by using the Paillier cryptosystem. On the cloud side, in order to utilize addition and multiplication homomorphism of the Paillier cryptosystem, three direction values of each patch are computed for constructing the corresponding histogram, which is shifted to embed watermark. For obtaining watermarking robustness, the robust interval is designed in the process of histogram shifting. The watermark can be extracted from the symmetrical direction histogram, and the original encrypted model can be restored by histogram shifting. Moreover, the process of watermark embedding and extraction are symmetric. Experimental results show that compared with the existing watermarking methods in encrypted 3D models, the quality of the decrypted model is improved. Moreover, the proposed method is robust to common attacks, such as translation, scaling, and Gaussian noise.

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3D Rebuilding for Impeller of Centrifugal Pump Based on ICT

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.130-134.1114 ◽

2011 ◽

Vol 130-134 ◽

pp. 1114-1118 ◽

Cited By ~ 1

Author(s):

Xiao Ping Jiang ◽

Wei Dong Shi ◽

Wei Li ◽

Hou Lin Liu ◽

Ming Gao Tan

Keyword(s):

Centrifugal Pump ◽

Volume Rendering ◽

3D Model ◽

Object Oriented ◽

3D Models ◽

Practical Application ◽

Pump Impeller ◽

Input And Output ◽

Complex Construction

In order to rebuild 3D models for pump impeller, the total inner complex construction data must be obtained at first. With the help of ICT, 367 ICT images with high quality of two typical impellers of centrifugal Pump were collected respectively, and format conversion from RAW to BMP was fulfilled though a developed program. Volume rendering was fulfilled based on these fault images, VC++ 6.0, MFC, ADO, VTK, and a series of digital image processing. A program named ReImpeller3D was developed on reverse engineering for pump impeller. The software is object-oriented and has several input and output interfaces, and also can supply geometrical models for numerical simulation, FEM, RP, digitized production, and redesign to production either. The practical application shows that it is feasible to use volume rendering to rebuild 3D model for pump impeller.

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