L. Théodon, T. Eremina, Kassem Dia, F. Lamadie, J. Pinoli, J. Debayle
This paper presents a new method for estimating the parameters of a stochastic geometric model for multiphase flow image processing using local measures. Local measures differ from global measures in that they are only based on a small part of a binary image and consequently provide different information of certain properties such as area and perimeter. Since local measures have been shown to be helpful in estimating the typical grain elongation ratio of a homogeneous Boolean model, the objective of this study was to use these local measures to statistically infer the parameters of a more complex non-Boolean model from a sample of observations. An optimization algorithm is used to minimize a cost function based on the likelihood of a probability densityof local measurements. The performance of the model is analysed using numerical experiments and real observations. The errors relative to real images of most of the properties of the model-generated images are less than 2%. The covariance and particle size distribution are also calculated and compared.
{"title":"Estimating the Parameters of a Stochastic Geometrical Model for Multiphase Flow Images Using Local Measures","authors":"L. Théodon, T. Eremina, Kassem Dia, F. Lamadie, J. Pinoli, J. Debayle","doi":"10.5566/ias.2638","DOIUrl":"https://doi.org/10.5566/ias.2638","url":null,"abstract":"This paper presents a new method for estimating the parameters of a stochastic geometric model for multiphase flow image processing using local measures. Local measures differ from global measures in that they are only based on a small part of a binary image and consequently provide different information of certain properties such as area and perimeter. Since local measures have been shown to be helpful in estimating the typical grain elongation ratio of a homogeneous Boolean model, the objective of this study was to use these local measures to statistically infer the parameters of a more complex non-Boolean model from a sample of observations. An optimization algorithm is used to minimize a cost function based on the likelihood of a probability densityof local measurements. The performance of the model is analysed using numerical experiments and real observations. The errors relative to real images of most of the properties of the model-generated images are less than 2%. The covariance and particle size distribution are also calculated and compared.","PeriodicalId":49062,"journal":{"name":"Image Analysis & Stereology","volume":"25 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87140394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
There is no apical morphological data being available for mandibular first or second premolars in the Turkish population. The aims of the study were (I) to assess apical morphological data of mandibular first and second premolars in a Turkish population at a young-adult age range (II) to analyze potential correlations between the size and position of the apical foramina (AF). Extracted sound teeth were collected from an adult volunteer population as willing to donate. Morphological data were obtained from specimens using a stereomicroscope. The number, size, shape, and position of AF and frequency of accessory foramina were quantified. Mann-Whitney U and Spearman's rank correlation tests were performed (α=0.05). A total of 237 teeth were investigated. The majority of the specimens had one major AF. The frequency of major AF was between 1–3 for both groups. The median AF size in mandibular first and second premolars were 55,180 µm2 and 67,483 µm2, respectively. The majority of foramina shape was irregular for the mandibular first premolars whereas, was oval for the second premolars. The median location of AF with respect to the anatomic apex was 664 µm in mandibular first premolars and 677 µm in mandibular second premolars. The size and location of AF mostly overlap between the mandibular first and second premolars. The shape of the AF might be the only relevant variation concerning the apical morphology between the mandibular first and second premolars in young adults. The interaction between the size and location of AF in mandibular premolars of young adults seems not significant
{"title":"Morphological Assessments of Root Apex of Permanent Mandibular First and Second Premolars in a Turkish Population","authors":"F. Babayeva, E. O. Orhan, O. Irmak","doi":"10.5566/ias.2577","DOIUrl":"https://doi.org/10.5566/ias.2577","url":null,"abstract":"There is no apical morphological data being available for mandibular first or second premolars in the Turkish population. The aims of the study were (I) to assess apical morphological data of mandibular first and second premolars in a Turkish population at a young-adult age range (II) to analyze potential correlations between the size and position of the apical foramina (AF). Extracted sound teeth were collected from an adult volunteer population as willing to donate. Morphological data were obtained from specimens using a stereomicroscope. The number, size, shape, and position of AF and frequency of accessory foramina were quantified. Mann-Whitney U and Spearman's rank correlation tests were performed (α=0.05). A total of 237 teeth were investigated. The majority of the specimens had one major AF. The frequency of major AF was between 1–3 for both groups. The median AF size in mandibular first and second premolars were 55,180 µm2 and 67,483 µm2, respectively. The majority of foramina shape was irregular for the mandibular first premolars whereas, was oval for the second premolars. The median location of AF with respect to the anatomic apex was 664 µm in mandibular first premolars and 677 µm in mandibular second premolars. The size and location of AF mostly overlap between the mandibular first and second premolars. The shape of the AF might be the only relevant variation concerning the apical morphology between the mandibular first and second premolars in young adults. The interaction between the size and location of AF in mandibular premolars of young adults seems not significant","PeriodicalId":49062,"journal":{"name":"Image Analysis & Stereology","volume":"14 12 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80196189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Robin Barman, Sudipta Saha, Md. Sayed Hossain, Anik Das, Md. Kaosar Ahmmad Rabby, A. Mahmud, Debasish Chowdhury
Neutron radiography (NR) has been applied successfully to investigate different types of building materials, rock samples, sculptures, statues or monuments for since long. The utilization of neutron imaging for non-invasive investigations of cultural heritage objects is demonstrated on the example of ancient bricks found in Mahasthangarh and Sonargaon, two key archaeological sites in Bangladesh. The visualization of the internal structure of different brick samples, by means of Neutron Radiography (NR), has been experimented using the BTRR research reactor in Bangladesh - the only neutron imaging facility available in Bangladesh for R D purposes. Manufacturing building materials have become a very good option for business in developing countries like Bangladesh. Among the non-destructive testing (NDT) techniques, neutron radiography is the most common procedure to identify light and organic materials, homogeneity, any inclusion or voids or cracks etc. inside the structure. The radiographic images in a dry condition for individual samples have been investigated. The image analysis was performed using ImageJ software and texture features were extracted using gray level co-occurrence matrix implemented by MATLAB for acquiring qualitative and quantitative information from this inspection technique at a high level of accuracy. The results obtained by neutron imaging provide the statement that the brick sample from Mahasthangarh is more homogeneous inside.
{"title":"Study of Structural Characteristics of Ancient Bricks With Neutron Radiography Facility at BTRR","authors":"Robin Barman, Sudipta Saha, Md. Sayed Hossain, Anik Das, Md. Kaosar Ahmmad Rabby, A. Mahmud, Debasish Chowdhury","doi":"10.5566/ias.2593","DOIUrl":"https://doi.org/10.5566/ias.2593","url":null,"abstract":"Neutron radiography (NR) has been applied successfully to investigate different types of building materials, rock samples, sculptures, statues or monuments for since long. The utilization of neutron imaging for non-invasive investigations of cultural heritage objects is demonstrated on the example of ancient bricks found in Mahasthangarh and Sonargaon, two key archaeological sites in Bangladesh. The visualization of the internal structure of different brick samples, by means of Neutron Radiography (NR), has been experimented using the BTRR research reactor in Bangladesh - the only neutron imaging facility available in Bangladesh for R D purposes. Manufacturing building materials have become a very good option for business in developing countries like Bangladesh. Among the non-destructive testing (NDT) techniques, neutron radiography is the most common procedure to identify light and organic materials, homogeneity, any inclusion or voids or cracks etc. inside the structure. The radiographic images in a dry condition for individual samples have been investigated. The image analysis was performed using ImageJ software and texture features were extracted using gray level co-occurrence matrix implemented by MATLAB for acquiring qualitative and quantitative information from this inspection technique at a high level of accuracy. The results obtained by neutron imaging provide the statement that the brick sample from Mahasthangarh is more homogeneous inside.","PeriodicalId":49062,"journal":{"name":"Image Analysis & Stereology","volume":"7 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75216159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We introduce a particular localization of the Minkowski functionals to characterize and discriminate different random spatial structures. The aim of this paper is to present a method estimating the typical grain elongation ratio in a homogeneous Boolean model. The use of this method is demonstrated on a range of Boolean models of rectangles featuring fixed and random elongation ratio. An optimization algorithm is performed to determine the elongation ratio which maximize the likelihood function of the probability density associated with the local perimeter measure. Therefore, the elongation ratio of the typical grain can be deduced.
{"title":"Local Measures Distribution for the Estimation of the Elongation Ratio of the Typical Grain in Homogeneous Boolean Models","authors":"T. Eremina, J. Debayle, F. Gruy, J. Pinoli","doi":"10.5566/IAS.2554","DOIUrl":"https://doi.org/10.5566/IAS.2554","url":null,"abstract":"We introduce a particular localization of the Minkowski functionals to characterize and discriminate different random spatial structures. The aim of this paper is to present a method estimating the typical grain elongation ratio in a homogeneous Boolean model. The use of this method is demonstrated on a range of Boolean models of rectangles featuring fixed and random elongation ratio. An optimization algorithm is performed to determine the elongation ratio which maximize the likelihood function of the probability density associated with the local perimeter measure. Therefore, the elongation ratio of the typical grain can be deduced.","PeriodicalId":49062,"journal":{"name":"Image Analysis & Stereology","volume":"49 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86373591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Segmentation of µm-resolution image data of irregularly shaped objects poses challenges to existing segmentation algorithms. This is especially true, when imperfections like noise, uneven lightning or traces of sample preparation are present in the image data. In this paper, considering electron micrographs of femoral quadriceps nerve sections of mice, a segmentation method to extract single axons surrounded by myelin sheaths is developed which is able to cope with various imperfections and artefacts. This approach successfully combines established methods like local thresholding and marker-based watershed transform to achieve a reliable segmentation of the given data. Indeed, the resulting segmentation map can be used to quantitatively determine geometrical characteristics of the axons and myelin sheaths. This is exemplified by modelling the joint probability distribution of axon area and myelin sphericity using a parametric copula approach, and by analysing the evolution of the model parameters for image data obtained from mice of different ages.
{"title":"Multidimensional characterisation of time-dependent image data: A case study for the peripheral nervous system in ageing mice","authors":"Matthias Weber, T. Wilhelm, Volker Schmidt","doi":"10.5566/ias.2499","DOIUrl":"https://doi.org/10.5566/ias.2499","url":null,"abstract":"Segmentation of µm-resolution image data of irregularly shaped objects poses challenges to existing segmentation algorithms. This is especially true, when imperfections like noise, uneven lightning or traces of sample preparation are present in the image data. In this paper, considering electron micrographs of femoral quadriceps nerve sections of mice, a segmentation method to extract single axons surrounded by myelin sheaths is developed which is able to cope with various imperfections and artefacts. This approach successfully combines established methods like local thresholding and marker-based watershed transform to achieve a reliable segmentation of the given data. Indeed, the resulting segmentation map can be used to quantitatively determine geometrical characteristics of the axons and myelin sheaths. This is exemplified by modelling the joint probability distribution of axon area and myelin sphericity using a parametric copula approach, and by analysing the evolution of the model parameters for image data obtained from mice of different ages.","PeriodicalId":49062,"journal":{"name":"Image Analysis & Stereology","volume":"31 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83350414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Local Binary Pattern (LBP) are considered as a classical descriptor for texture analysis, it has mostly been used in pattern recognition and computer vision applications. However, the LBP gets information from a restricted number of local neighbors which is not enough to describe texture information, and the other descriptors that get a large number of local neighbors suffer from a large dimensionality and consume much time. In this regard, we propose a novel descriptor for texture classification known as Circular Parts Local Binary Pattern (CPLBP) which is designed to enhance LBP by extending the area of neighborhood from one to a region of neighbors using polar coordinates that permit to capture more discriminating relationships that exists amongst the pixels in the local neighborhood which increase efficiency in extracting features. Firstly, the circle is divided into regions with a specific radius and angle. After that, we calculate the average gray-level value of each part. Finally, the value of the center pixel is compared with these average values. The relevance of the proposed idea is validate in databases Outex 10 and 12. A complete evaluation on benchmark data sets reveals CPLBP's high performance. CPLBP generates the score of 99.95 with SVM classification.
{"title":"A Novel Texture Descriptor: Circular Parts Local Binary Pattern","authors":"Ibtissam Al Saidi, M. Rziza, J. Debayle","doi":"10.5566/IAS.2580","DOIUrl":"https://doi.org/10.5566/IAS.2580","url":null,"abstract":"Local Binary Pattern (LBP) are considered as a classical descriptor for texture analysis, it has mostly been used in pattern recognition and computer vision applications. However, the LBP gets information from a restricted number of local neighbors which is not enough to describe texture information, and the other descriptors that get a large number of local neighbors suffer from a large dimensionality and consume much time. In this regard, we propose a novel descriptor for texture classification known as Circular Parts Local Binary Pattern (CPLBP) which is designed to enhance LBP by extending the area of neighborhood from one to a region of neighbors using polar coordinates that permit to capture more discriminating relationships that exists amongst the pixels in the local neighborhood which increase efficiency in extracting features. Firstly, the circle is divided into regions with a specific radius and angle. After that, we calculate the average gray-level value of each part. Finally, the value of the center pixel is compared with these average values. The relevance of the proposed idea is validate in databases Outex 10 and 12. A complete evaluation on benchmark data sets reveals CPLBP's high performance. CPLBP generates the score of 99.95 with SVM classification.","PeriodicalId":49062,"journal":{"name":"Image Analysis & Stereology","volume":"20 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85520953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Bertram, L. Cruz-Orive, S. M. Evans, D. Hyde, T. Mayhew, Matthias Ochs, Yong Tang, J. Nyengaard
Professor Hans Jørgen G. Gundersen MD, DMSc (1943–2021) was a pioneering stereologist whose work has inspired and influenced researchers across the world for almost half a century. He was a charismatic character and one of the founding fathers of modern stereology, whose achievements and contributions are fondly remembered below by colleagues and co-workers. It was an enormous pleasure to be in his company and although future generation will miss this opportunity, his work will live on, to inspire and influence future generations of researchers.
Hans Jørgen G. Gundersen博士，理学硕士(1943-2021)是一位开创性的立体学家，他的工作在近半个世纪的时间里启发和影响了世界各地的研究人员。他是一个极具魅力的人物，也是现代立体学的奠基人之一，他的成就和贡献在下面被同事和同事们深情地铭记。这是一个巨大的快乐在他的公司，虽然后代会错过这个机会，他的工作将继续存在，激励和影响下一代的研究人员。
{"title":"Personal Reflections on the Life of Hans Jørgen Gottlieb Gundersen","authors":"J. Bertram, L. Cruz-Orive, S. M. Evans, D. Hyde, T. Mayhew, Matthias Ochs, Yong Tang, J. Nyengaard","doi":"10.5566/ias.2596","DOIUrl":"https://doi.org/10.5566/ias.2596","url":null,"abstract":"Professor Hans Jørgen G. Gundersen MD, DMSc (1943–2021) was a pioneering stereologist whose work has inspired and influenced researchers across the world for almost half a century. He was a charismatic character and one of the founding fathers of modern stereology, whose achievements and contributions are fondly remembered below by colleagues and co-workers. It was an enormous pleasure to be in his company and although future generation will miss this opportunity, his work will live on, to inspire and influence future generations of researchers.","PeriodicalId":49062,"journal":{"name":"Image Analysis & Stereology","volume":"7 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76995799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Moreaud, Giulia Ferri, S. Humbert, M. Digne, J. Schweitzer
For the development of a new porous material such as catalytic carrier, the control of the textural properties is of fundamental importance. In order to move towards rational synthesis, it is necessary to better understand the physical phenomena that generate a defined solid structure. A contribute to this purpose can be achieved by studying the aggregation process inside colloidal suspensions, leading to porosity generation: this phenomenon can be described with a Brownian dynamics model that, for any set of chemical parameters, gives access to the mass distribution and the fractal dimension of colloidal aggregates. However, this model cannot be used for the simulation of large colloidal systems, due to its high computational time, limiting comparison with analytical methods, which probe the whole multi-scale system. This problem is solved by developing a new aggregation morphological model, wherein the fractal dimension is tuned with two compactness parameters. An efficient simulation algorithm is proposed in case of spheres, for which the fractal dimension of the generated aggregates varies between 1.2 and 3. Brownian dynamics results are used to parametrize this purely geometric model, in order to constrain the size and the morphology of the aggregates created. The large numerical solid will be representative of the textural properties of a real solid and will give more information on the porous network. It could be used, for example, to simulate diffusive transport coupled with chemical reaction and to study the impact of the geometry of the porous system on the catalytic performance.
{"title":"SIMULATION OF LARGE AGGREGATE PARTICLES SYSTEM WITH A NEW MORPHOLOGICAL MODEL","authors":"M. Moreaud, Giulia Ferri, S. Humbert, M. Digne, J. Schweitzer","doi":"10.5566/IAS.2488","DOIUrl":"https://doi.org/10.5566/IAS.2488","url":null,"abstract":"For the development of a new porous material such as catalytic carrier, the control of the textural properties is of fundamental importance. In order to move towards rational synthesis, it is necessary to better understand the physical phenomena that generate a defined solid structure. A contribute to this purpose can be achieved by studying the aggregation process inside colloidal suspensions, leading to porosity generation: this phenomenon can be described with a Brownian dynamics model that, for any set of chemical parameters, gives access to the mass distribution and the fractal dimension of colloidal aggregates. However, this model cannot be used for the simulation of large colloidal systems, due to its high computational time, limiting comparison with analytical methods, which probe the whole multi-scale system. This problem is solved by developing a new aggregation morphological model, wherein the fractal dimension is tuned with two compactness parameters. An efficient simulation algorithm is proposed in case of spheres, for which the fractal dimension of the generated aggregates varies between 1.2 and 3. Brownian dynamics results are used to parametrize this purely geometric model, in order to constrain the size and the morphology of the aggregates created. The large numerical solid will be representative of the textural properties of a real solid and will give more information on the porous network. It could be used, for example, to simulate diffusive transport coupled with chemical reaction and to study the impact of the geometry of the porous system on the catalytic performance.","PeriodicalId":49062,"journal":{"name":"Image Analysis & Stereology","volume":"2 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83035400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Virtual reality is increasingly used in medicine for diagnostics, for visualisation of complex structures and for preoperative planning. In interventional radiology, minimally invasive approach could be described with a target point representing the desired needle tip position and an array of all possible trajectories leading to it resembling irregular “cone” or “pyramid”. We present a pilot study of planning a minimally invasive posterior infrazygomatic and suprazygomatic approaches into the pterygopalatine fossa using a solid angle as a measure of size of the approach in five virtually reconstructed heads. The minimally invasive approaches were planned by manually drawing the edges of “pyramids” that described each approach in 3D using virtual reality program Tracer. For each head, a transverse diameter was measured and for each approach a solid angle size, average edge length and estimated area on the skin from where the target point could be reached were calculated. We found that, the solid angle of posterior infrazygomatic approach was significantly larger than suprazygomatic approach (p0.001). Furthermore, the transverse head diameter and solid angle in posterior infrazygomatic approach were negatively correlated (ρ=-0.55, p=0.0002), while transverse head diameter and the estimated area on the skin from where the target point could be reached in the suprazygomatic approach were positively correlated (ρ=0.37, p=0.0206). In conclusion, our findings provide important preliminary evidence on the feasibility of evaluating and comparing different minimally invasive approaches using virtual reality systems, and affirm the validity of solid angle as a measure of the size of the approach.
{"title":"QUANTIFICATION OF THE INTERVENTIONAL APPROACHES INTO THE PTERYGOPALATINE FOSSA BY SOLID ANGLES USING VIRTUAL REALITY","authors":"A. Jerman, J. Janáček, Ž. Snoj, N. Umek","doi":"10.5566/ias.2581","DOIUrl":"https://doi.org/10.5566/ias.2581","url":null,"abstract":"Virtual reality is increasingly used in medicine for diagnostics, for visualisation of complex structures and for preoperative planning. In interventional radiology, minimally invasive approach could be described with a target point representing the desired needle tip position and an array of all possible trajectories leading to it resembling irregular “cone” or “pyramid”. We present a pilot study of planning a minimally invasive posterior infrazygomatic and suprazygomatic approaches into the pterygopalatine fossa using a solid angle as a measure of size of the approach in five virtually reconstructed heads. The minimally invasive approaches were planned by manually drawing the edges of “pyramids” that described each approach in 3D using virtual reality program Tracer. For each head, a transverse diameter was measured and for each approach a solid angle size, average edge length and estimated area on the skin from where the target point could be reached were calculated. We found that, the solid angle of posterior infrazygomatic approach was significantly larger than suprazygomatic approach (p0.001). Furthermore, the transverse head diameter and solid angle in posterior infrazygomatic approach were negatively correlated (ρ=-0.55, p=0.0002), while transverse head diameter and the estimated area on the skin from where the target point could be reached in the suprazygomatic approach were positively correlated (ρ=0.37, p=0.0206). In conclusion, our findings provide important preliminary evidence on the feasibility of evaluating and comparing different minimally invasive approaches using virtual reality systems, and affirm the validity of solid angle as a measure of the size of the approach. ","PeriodicalId":49062,"journal":{"name":"Image Analysis & Stereology","volume":"32 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77788837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Pietrzak, A. Gładki, A. Strojny-Nędza, T. Wejrzanowski, K. Kaszyca
Tomography allows embedding of one space in another, especially ℛ2 → ℛ3, and observation of the nature of the volumetric internal composite structure. Now, not only a simple interpretation is expected of geometry defined via single thresholds of structures. The binary segmentation used for numerical structure analysis requires more detailed presentation. This paper shows an example of image analysis techniques applied to study the homogeneity of two-phase material. Using tomography analysis, the results of the homogeneity of the SiC particles with 10vol.%, 20vol.%, 30vol.%, 40vol.% volumetric bulk density of Cu/SiC composites are presented. Finally, for two independent coordinate systems, the distribution of SiC particle masses and their total moments of inertia were determined. The results confirmed that for well-mixed composite powders the homogeneity of the reinforcing phase is expected in samples with a SiC volume near 30vol.%. In this case, segregation by translation and rotation of SiC particles in the matrix, during the sintering process is restricted.
{"title":"Analysis of Isotropy and Uniformity of the Distribution of Reinforcing Phase in Cu/SiC Composite Materials Using μCT Methods","authors":"K. Pietrzak, A. Gładki, A. Strojny-Nędza, T. Wejrzanowski, K. Kaszyca","doi":"10.5566/IAS.1911","DOIUrl":"https://doi.org/10.5566/IAS.1911","url":null,"abstract":"Tomography allows embedding of one space in another, especially ℛ2 → ℛ3, and observation of the nature of the volumetric internal composite structure. Now, not only a simple interpretation is expected of geometry defined via single thresholds of structures. The binary segmentation used for numerical structure analysis requires more detailed presentation. This paper shows an example of image analysis techniques applied to study the homogeneity of two-phase material. Using tomography analysis, the results of the homogeneity of the SiC particles with 10vol.%, 20vol.%, 30vol.%, 40vol.% volumetric bulk density of Cu/SiC composites are presented. Finally, for two independent coordinate systems, the distribution of SiC particle masses and their total moments of inertia were determined. The results confirmed that for well-mixed composite powders the homogeneity of the reinforcing phase is expected in samples with a SiC volume near 30vol.%. In this case, segregation by translation and rotation of SiC particles in the matrix, during the sintering process is restricted.","PeriodicalId":49062,"journal":{"name":"Image Analysis & Stereology","volume":"15 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77481979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：