scholarly journals Functional aspects of the Eustachian tube by means of 3D-modeling

PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0244909
Author(s):  
Robert Schuon ◽  
Josef Schwarzensteiner ◽  
Gerrit Paasche ◽  
Thomas Lenarz ◽  
Samuel John
Keyword(s):  
Eustachian Tube ◽  
Functional Anatomy ◽  
Three Dimensional ◽  
Chronic Otitis Media ◽  
Subsequent Development ◽  
Underlying Mechanism ◽  
Three Dimensional Model ◽  
Valve Mechanism ◽  
Functional Aspects ◽  
The Individual

The extent of dysfunction of the Eustachian tube (ET) is relevant in understanding the pathogenesis of secondary otological diseases such as acute or chronic otitis media. The underlying mechanism of ET dysfunction remains poorly understood except for an apparent genesis such as a nasopharyngeal tumor or cleft palate. To better describe the ET, its functional anatomy, and the biomechanical valve mechanism and subsequent development of diagnostic and interventional tools, a three-dimensional model based on thin-layer histology was created from an ET in this study. Blackface sheep was chosen as a donor. The 3-D model was generated by the coherent alignment of the sections. It was then compared with the cone-beam computed tomography dataset of the complete embedded specimen taken before slicing. The model shows the topographic relation of the individual components, such as the bone and cartilage, the muscles and connective tissue, as well as the lining epithelium with the lumen. It indicates a limited spiraling rotation of the cartilaginous tube over its length and relevant positional relationships of the tensor and levator veli palatine muscles.

scholarly journals Functional Aspects of the Eustachian Tube by Means of 3D-Modeling

2020 ◽  
Author(s):  
Schuon Robert ◽  
Josef Schwarzensteiner ◽  
Gerrit Paasche ◽  
Lenarz Thomas ◽  
Samuel John
Keyword(s):  
Eustachian Tube ◽  
Functional Anatomy ◽  
Three Dimensional ◽  
Chronic Otitis Media ◽  
Subsequent Development ◽  
Underlying Mechanism ◽  
Three Dimensional Model ◽  
Valve Mechanism ◽  
Functional Aspects ◽  
The Individual

AbstractThe extent of dysfunction of the Eustachian tube (ET) is relevant in understanding the pathogenesis of secondary otological diseases such as acute or chronic otitis media. The underlying mechanism of ET dysfunction remains poorly understood except for an apparent genesis such as a nasopharyngeal tumor or cleft palate. To better describe the ET, its functional anatomy, and the biomechanical valve mechanism and subsequent development of diagnostic and interventional tools, a three-dimensional model based on thin-layer histology was created from an ET in this study. Blackface sheep was chosen as a donor. The 3-D model was generated by the coherent alignment of the sections. It was then compared with the cone-beam computed tomography dataset of the complete embedded specimen taken before slicing. The model shows the topographic relation of the individual components, such as the bone and cartilage, the muscles and connective tissue, as well as the lining epithelium with the lumen. It indicates a limited spiraling rotation of the cartilaginous tube over its length and relevant positional relationships of the tensor and levator veli palatine muscles.

Phonetic iconicity in the evaluative morphology of a sample of Indo-European, Niger-Congo and Austronesian languages

2010 ◽  
Vol 3 (2) ◽  
pp. 156-180 ◽  
Author(s):  
Renáta Gregová ◽  
Lívia Körtvélyessy ◽  
Július Zimmermann
Keyword(s):  
Three Dimensional ◽  
Sound Symbolism ◽  
Three Dimensional Model ◽  
Austronesian Languages ◽  
Place Of Articulation ◽  
European Languages ◽  
Phonetic Symbolism ◽  
The Individual ◽  
Core Vocabulary

Universals Archive (Universal #1926) indicates a universal tendency for sound symbolism in reference to the expression of diminutives and augmentatives. The research ( Štekauer et al. 2009 ) carried out on European languages has not proved the tendency at all. Therefore, our research was extended to cover three language families – Indo-European, Niger-Congo and Austronesian. A three-step analysis examining different aspects of phonetic symbolism was carried out on a core vocabulary of 35 lexical items. A research sample was selected out of 60 languages. The evaluative markers were analyzed according to both phonetic classification of vowels and consonants and Ultan's and Niewenhuis' conclusions on the dominance of palatal and post-alveolar consonants in diminutive markers. Finally, the data obtained in our sample languages was evaluated by means of a three-dimensional model illustrating the place of articulation of the individual segments.

scholarly journals The Localization of Activity Sources in a Three-Dimensional Model of the Human Brain Using the Joint Analysis of EEG / sMRI Data

2019 ◽  
Vol 17 (3) ◽  
pp. 18-28
Author(s):  
E. Bykova ◽  
A. Savostyanov
Keyword(s):  
Inverse Problem ◽  
Brain Activity ◽  
Three Dimensional ◽  
Human Head ◽  
Joint Analysis ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Use Of Data ◽  
The Individual ◽  
The Brain

Despite the large number of existing methods of the diagnosis of the brain, brain remains the least studied part of the human body. Electroencephalography (EEG) is one of the most popular methods of studying of brain activity due to its relative cheapness, harmless, and mobility of equipment. While analyzing the EEG data of the brain, the problem of solving of the inverse problem of electroencephalography, the localization of the sources of electrical activity of the brain, arises. This problem can be formulated as follows: according to the signals recorded on the surface of the head, it is necessary to determine the location of sources of these signals in the brain. The purpose of my research is to develop a software system for localization of brain activity sources based on the joint analysis of EEG and sMRI data. There are various approaches to solving of the inverse problem of EEG. To obtain the most exact results, some of them involve the use of data on the individual anatomy of the human head – structural magnetic resonance imaging (sMRI data). In this paper, one of these approaches is supposed to be used – Electromagnetic Spatiotemporal Independent Component Analysis (EMSICA) proposed by A. Tsai. The article describes the main stages of the system, such as preprocessing of the initial data; the calculation of the special matrix of the EMSICA approach, the values of which show the level of activity of a certain part of the brain; visualization of brain activity sources on its three-dimensional model.

scholarly journals Rehabilitation of a Patient with Temporomandibular Joint Disorder and Misocclusion Requiring Full Mouth Reconstruction, Based on the Multidisciplinary Approach (A Clinical Case)

2020 ◽  
Author(s):  
Fatima Dzalaeva ◽  
Sergey Chikunov ◽  
Anatoly Utyuzh ◽  
Maria Mikhailova ◽  
Marzhanat Budunova
Keyword(s):  
Multidisciplinary Approach ◽  
Three Dimensional ◽  
Three Dimensional Model ◽  
Results Of Treatment ◽  
Rehabilitation System ◽  
Assessment And Treatment ◽  
Joint Disorder ◽  
Therapeutic Measures ◽  
The Individual ◽  
Mandibular Movements

AbstractThis case report involved the development of a rehabilitation system for patient with edentulism and an algorithm for diagnostic and therapeutic measures to be planned based on the patient’s individual anatomical and physiological features. The results of treatment and rehabilitation made it possible to achieve the optimal distribution of loads on the dentition. It was shown that it is necessary to analyze casts in an articulator to reproduce a three-dimensional model of mandibular movements taking into account the individual features of the patient to obtain a satisfactory assessment and treatment planning of patients with edentulism requiring full mouth reconstruction. This case confirms that the developed algorithm is anatomically and pathogenetically justified, as it considers all changes and interrelationships of structures of the dentition.

scholarly journals CFD ANALYSIS OF ECONOMIZER IN A TENGENTIAL FIRED BOILER

2013 ◽  
pp. 143-147
Author(s):  
KRUNAL P. MUDAFALE ◽  
HEMANT S. FARKADE
Keyword(s):  
Flue Gas ◽  
Power Plants ◽  
Large Scale ◽  
Thermal Power ◽  
Three Dimensional ◽  
Geometrical Model ◽  
Gas Temperature ◽  
Three Dimensional Model ◽  
The Individual ◽  
Side Flow

This paper presents a simulation of the economizer zone, which allows for the condition of the shell-side flow and tube-side and tube-wall, thermal fields, and of the shell-tube heat-exchange. Selection of the economizer zone from the thermal power plant only because, it is found trends of failure that the economizer is the zone where the leakages are found more. The maximum number of cause of failure in economizer unit is due to flue gas erosion. The past failure details revels that erosion is more in U-bend areas of Economizer Unit because of increase in flue gas velocity near these bends. But it is observed that the velocity of flue gases surprisingly increases near the lower bends as compared to upper ones. The model is solved using conventional CFD techniques by STAR- CCM+ software. In which the individual tubes are treated as sub-grid features. A geometrical model is used to describe the multiplicity of heat-exchanging structures and the interconnections among them. The Computational Fluid Dynamics (CFD) approach is utilised for the creation of a three-dimensional model of the economizer coil. With equilibrium assumption applied for description of the system chemistry. The flue gas temperature, pressure and velocity field of fluid flow within an economizer tube using the actual boundary conditions have been analyzed using CFD tool. Such as the ability to quickly analyse a variety of design options without modifying the object and the availability of significantly more data to interpret the results. This study is a classic example of numerical investigation into the problem of turbulent reacting flows in large scale furnaces employed in thermal power plants for the remediation of ash deposition problems. And the experimental setup is from Chandrapur Super Thermal Power Station, Chandrapur having the unit no IV of 210 MW energy generations.

scholarly journals Influence of Geometric Features Associativity of CAD Class Models on the Process of Their Updating – Comparative Analysis

2021 ◽  
Author(s):  
Grzegorz Świaczny
Keyword(s):  
3D Model ◽  
Three Dimensional ◽  
Optimal Solution ◽  
3D Models ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Initial Design ◽  
The Individual ◽  
Class Models ◽  
Positive Effect

This article deals with the topic of one of the most important features of modern CAx class systems – associativity. The term refers to the ability to form relations (links) between two or more objects (in terms of their selected features), and with the consequence creating an associative (linked) three-dimensional model. The author pays special attention to the very process of creating relations between objects, as it has a key impact on the structural stability of CAD class models, and thus on their susceptibility to possible modifications. To show that not all associativity brings a positive effect, the author presents two examples of its implementation. In order to emphasize the influence of the method of linking individual elements, both examples are based on the same 3D model – a thin-walled part with a positioning pin. That means the geometric form of the default part is the same, whereas only relations of the individual objects of the 3D model change. In the first scenario, correctly defined relations between objects make that the positioning pin offset does not affect the initial design conditions. The second scenario shows an incorrect implementation of associativity, as a result of which the same operation of positioning pin offset gives non-compliance with the initial design conditions and with the consequence an undesirable change in its geometry. The article is an attempt to draw attention to the fact that the associative structure of 3D models is not always equal to the optimal solution. Only the well-thought-out nature of associativity allows to use all its advantages.

A Model for Bending, Torsional, and Axial Vibrations of Micro- and Macro-Drills Including Actual Drill Geometry—Part I: Model Development and Numerical Solution

2010 ◽  
Vol 132 (4) ◽  
Author(s):  
Sinan Filiz ◽  
O. Burak Ozdoganlar
Keyword(s):  
Cross Section ◽  
Model Development ◽  
Three Dimensional ◽  
Circular Cross Section ◽  
Three Dimensional Model ◽  
Axial Thrust ◽  
One Dimensional ◽  
Three Dimensional Models ◽  
The Individual ◽  
Actual Geometry

Part I of this work presents a combined one-dimensional/three-dimensional approach for obtaining a unified model for the dynamics of micro- and macro-drills. To increase the numerical efficiency of the model, portions of the drill with circular cross-section (shank, extension, and tapered sections) are modeled using one-dimensional beam models without compromising model accuracy. A three-dimensional model is used for an accurate representation of the fluted section, considering the actual geometry with the pretwisted shape and axially varying (nonaxisymmetric) cross-section. The actual cross-section of the drills is incorporated to the model through a polynomial mapping while the pretwist effect is captured by defining a rotating reference frame. The boundary-value problem for both one- and three-dimensional models are derived using a variational approach, based on the extended Hamilton’s principle, and are subsequently solved by applying the spectral-Tchebychev technique. A component-mode synthesis is used for connecting the individual sections to obtain the dynamic model for the entire drill. Convergence of the model is studied by varying the number of polynomials for each section. The experimental validation of the model is included in Part II for both macro- and micro-drills. Also included in Part II is an analysis of drill dynamics for varying drill-geometry parameters and axial (thrust) force.

Application of Knowledge Management in E-Commerce Based on Fuzzy Theory

2013 ◽  
Vol 475-476 ◽  
pp. 1207-1210
Author(s):  
Cheng Yu ◽  
Shi Wei Lin
Keyword(s):  
Knowledge Management ◽  
Fuzzy Theory ◽  
Three Dimensional ◽  
System Model ◽  
Sustainable Competitive Advantage ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Business System ◽  
The Individual ◽  
The Relationship

Basing on the introduction in the knowledge management and E-commerce concept and main theory, this paper discusses the relationship between knowledge management and E-commerce, put forward E-commerce to build the foundation o f knowledge, information flow and organization structure for knowledge management and the thesis that knowledge management constructs the sustainable competitive advantage for E-commerce. It also compares and analyzes the knowledge management and E-commerce popular model, Proposes the individual-centered organization, knowledge and business three dimensional model and the knowledge and business system model of business process which is based on the former.

Heat flow in the presence of topography: Numerical analysis of data ensembles

Geophysics ◽  
1985 ◽  
Vol 50 (8) ◽  
pp. 1335-1341 ◽  
Author(s):  
Steven G. Henry ◽  
Henry N. Pollack
Keyword(s):  
Heat Flow ◽  
Surface Temperature ◽  
Three Dimensional ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Near Surface ◽  
Peruvian Andes ◽  
Variable Surface ◽  
The Individual ◽  
Variable Surface Temperature

We present a method of estimating subsurface temperatures and true regional heat flow in the presence of perturbing topography, variable surface temperature, and subsurface thermal conductivity contrasts. The method involves solution of the steady‐state three‐dimensional heat conduction equation by finite‐difference numerical techniques. The topography is represented by an irregular upper boundary and the variable surface temperature as a boundary condition along the irregular upper surface. Internal structural configurations and conductivity contrasts are easily accommodated. The principal variable input into the system is the deep basal (unperturbed) heat flow. The best value of heat flow is obtained by minimizing, in a least‐squares sense, the differences between observed and calculated temperatures. Temperature observations commonly are distributed irregularly in the near‐surface (perturbed) environment, in multiple vertical or inclined boreholes, tunnels, and/or mine galleries. The method is particularly suited to simultaneous analysis of an ensemble of distributed observations, in contrast to methods that focus on the perturbation to the temperature gradient in the vicinity of a single borehole. We used the method to reduce data obtained at fifteen newly established heat flow sites in the Bolivian and Peruvian Andes. We illustrate with three examples—a two‐dimensional model from the Bolivar Mine, Bolivia; (2) a three‐dimensional model using variable conductivity from the Cerro Verde Mine, Peru; and (3) a three‐dimensional model at the Colquiri Mine, Bolivia where temperature measurements were few and the distance between the individual boreholes was fairly large.

scholarly journals La torre nella torre. Recupero e rilievo 3D per la fruizione della Torre Matta ad Otranto

X ◽  
2020 ◽  
Author(s):  
Giovanna Muscatello
Keyword(s):  
Fifteenth Century ◽  
Three Dimensional ◽  
Three Dimensional Model ◽  
Architectural Features ◽  
Virtual Visits ◽  
Late Fifteenth ◽  
The Individual ◽  
First Time ◽  
The Relationship ◽  
The City

The tower in the tower. Recovery and 3D survey for virtual visits to the Torre Matta in OtrantoOtranto is one of the biggest ancient settlements in the Salento (Puglia), in the easternmost part of the Italian peninsula. This location has always affected the city’s history, which has a stratified system of defence. As a result of the Turkish invasion of 1480, the city was completely destroyed. During the counter-offensive of 1481 the city was reconquered by the Aragonese, who are credited with the reconstruction of the city and its defences, building high walls with circular towers (still visible and well conserved), which housed artillery pieces on the various floors of the casemates. Around the mid sixteenth century the existing defensive structures were enriched with bastions including the imposing pentagonal structure that incorporates the circular tower of the late fifteenth century, the so-called Torre Matta, facing the harbour. As part of recent recovery measures, the enormous room inside the bastion was completely emptied. This entailed removing all the accumulated material which, over the years, had come to fill the entire space. This material obscured the external wall of the fifteenth century tower enclosed within the bastion, of which, at the beginning of the work, only the stone corbels and the blind arches at the top were visible. The material had also prevented access via the only original entrance, on the south-east side, which was on the level of the moat. The stratified deposits to be removed were about 18 m deep, and the operation served to bring to light the entire room and the tower, making it possible for the first time to appreciate the relationship between the walls. To record the geometry of the individual architectural features, a 3D laser scan was performed, integrated with direct surveys. A three-dimensional model was created in order to enable virtual visits and disseminate knowledge of the monument.

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