Proper Triangulation Research Articles

Contribuição das ecoinovações na formação de capacidades dinâmicas: evidências do segmento sucroenergético de São Paulo

Objective: To characterize the dynamic capabilities of four selected companies in the sugar-energy segment, which incorporate eco-innovations in their businesses.Methodology: Empirical research of a qualitative nature and explanatory approach, involving the multiple case study method, with the proper triangulation of data.Originality: In the literature, there are few studies involving the redesign of industrial parks for eco-industrial parks that provide opportunities for the presence of eco-innovation and the development of dynamic capabilities. This phenomenon characterizes industrial parks that are environmentally oriented in their production processes, whether in their base technology, in raw materials, in production energy, in the structure of the organization and in the institutional structure of the industrial ecosystem.Main results: The cross analysis of the data and information collected indicated the presence of dynamic capabilities aimed at the sustainability of their businesses, based on the fundamentals of energy origin.Theoretical contributions: Using the approach of Tondolo and Bitencourt (2014) it was possible to explain the type of implication of eco-innovations on dynamic capabilities and on business. The scenario of the influence of eco-innovations described on the competitive behavior of the companies studied shows a direct connection with dynamic capabilities, points to the existence of a logical path and allows for important considerations to be established in relation to [a] perception of eco-innovations as a strategic opportunity, [b] find the procedural or technological change that would solve their environmental problems, [c] develop real and latent dynamic capabilities and [d] the systemic solution involved the guided use of the capabilities that characterize the dynamic environment of these companies.Managerial contributions: Knowing the trajectory of environmental innovations introduced in the sugar-energy segment, with the inclusion of biotechnologies developed in the country or adapted to our reality, helps in the configuration of favorable environments for the emergence of eco-innovative solutions that meet the SDG agenda of UN. The identified dynamic capabilities span the three main product categories – sugar, ethanol and energy – and allowed for a strategic realignment supported by a new core business: clean energy.

Does an Experienced Laparoscopic Surgeon Need a Long Learning Curve to Start Robotic Single Site Cholecystectomy?

Purpose: It is well known that a laparoscopic single site cholecystectomy has significant limitations associated with proper triangulation and instrument crowding and collisions. Although the da Vinci Single Site robotic system has been proposed to overcome these problems, the Single Site technology is non-wristed and, unlike other conventional robotic instruments, only provides rotation, the ergonomics. Therefore, many surgeons are reluctant to start robotic single site cholecystectomy (RSSC). The purpose of this study is to demonstrate that an experienced laparoscopic surgeon can safely RSSC with less learning curves using the robotic single site platform by showing objective data by single experienced surgeon.

Single-Port Laparoscopic Cholecystectomy Assisted with Neodymium Magnets: Initial Prospective Experience with 60 Cases

Introduction: Laparoscopic cholecystectomy (LC) is the gold standard performed by the majority of surgeons worldwide, and the use of single-port cholecystectomy remains a matter of debate. Single-port magnetic-assisted cholecystectomy (SPMAC) was described as an alternative because of its ability for proper triangulation and the advantage of reducing port surgery. The objective of this study is to describe the initial experience of SPMAC and evaluate the surgical learning curve. Materials and Methods: A prospective cohort was conducted between February 2017 and August 2018; 60 patients completed the inclusion criteria. Variables analyzed were gender, age, body mass index, American Society of Anesthesiologist (ASA) classification, operative time, hospital stay, intraoperative bleeding, and conversion rate. Postoperative pain was measured with a visual analogue scale (VAS). Aesthetic perception was measured by the cosmetic visual analogue scale (CVAS). The postoperative complications were graded according to Clavien-Dindo classification, and the cumulative sum (CUSUM) model was used for evaluating the learning curve. Results: The mean operatory time was 56.1 minutes. With regard to the postoperative pain variable, the VAS value was 2 out of 10 in 78.33% of patients. With regard to aesthetic satisfaction, CVAS was reported to be 10 out of 10 in 96.67% of patients. Conversion rate was 0%. The learning curve of operative time was reached at the 22nd patient, according to the CUSUM chart. Conclusions: SPMAC is feasible and effective; in our consideration, an acceptable learning curve considering benign gallbladder pathology is one of the most prevalent in general surgery. Further comparative studies with conventional LC and SPMAC need to be performed to conduct a proper comparison.

Towards a phase diagram for spin foams

One of the most pressing issues for loop quantum gravity and spin foams is the construction of the continuum limit. In this paper, we propose a systematic coarse-graining scheme for three-dimensional lattice gauge models including spin foams. This scheme is based on the concept of decorated tensor networks, which have been introduced recently. Here we develop an algorithm applicable to gauge theories with non-Abelian groups, which for the first time allows for the application of tensor network coarse-graining techniques to proper spin foams. The procedure deals efficiently with the large redundancy of degrees of freedom resulting from gauge invariance. The algorithm is applied to 3D spin foams defined on a cubical lattice which, in contrast to a proper triangulation, allows for non-trivial simplicity constraints. This mimics the construction of spin foams for 4D gravity. For lattice gauge models based on a finite group we use the algorithm to obtain phase diagrams, encoding the continuum limit of a wide range of these models. We find phase transitions for various families of models carrying non-trivial simplicity constraints.

Constructing Intrinsic Delaunay Triangulations from the Dual of Geodesic Voronoi Diagrams

Intrinsic Delaunay triangulation (IDT) naturally generalizes Delaunay triangulation from R 2 to curved surfaces. Due to many favorable properties, the IDT whose vertex set includes all mesh vertices is of particular interest in polygonal mesh processing. To date, the only way for constructing such IDT is the edge-flipping algorithm, which iteratively flips non-Delaunay edges to become locally Delaunay. Although this algorithm is conceptually simple and guarantees to terminate in finite steps, it has no known time complexity and may also produce triangulations containing faces with only two edges. This article develops a new method to obtain proper IDTs on manifold triangle meshes. We first compute a geodesic Voronoi diagram (GVD) by taking all mesh vertices as generators and then find its dual graph. The sufficient condition for the dual graph to be a proper triangulation is that all Voronoi cells satisfy the so-called closed ball property. To guarantee the closed ball property everywhere, a certain sampling criterion is required. For Voronoi cells that violate the closed ball property, we fix them by computing topologically safe regions, in which auxiliary sites can be added without changing the topology of the Voronoi diagram beyond them. Given a mesh with n vertices, we prove that by adding at most O ( n ) auxiliary sites, the computed GVD satisfies the closed ball property, and hence its dual graph is a proper IDT. Our method has a theoretical worst-case time complexity O ( n 2 + tn log n ), where t is the number of obtuse angles in the mesh. Computational results show that it empirically runs in linear time on real-world models.

Aspects to be considered in case of variable surfaces modelling

Proper triangulation will bring benefits regarding the numerical conditioning of nodes within the point cloud but will also allow certain nodes to be able to move around those that are neighboring them. In this way, surface features as chained regions or curves will have a certain degree of freedom which will allow them to slide one towards another. At a more careful evaluation there is a major drawback in terms of lack of possibility to take into consideration the operations which depend upon approximate shapes inside the ideal shape evaluation process. In order to be able to control the accuracy of the process there is an impetuous need for all surfaces to be described functionally. Any triangulation procedure has to be able to allow control over the analyzed surface topology and any other after modifications: dividing the surface along an incorporated curve in order to define a new edge or sticking two surfaces together in order to form a mutual boundary edge.

An automatic method for generating carbon nanostructure atomistic models using hexagonal meshes with properly distributed defects

SummaryAtomistic models, which are crucial for performing molecular dynamics simulations of carbon nanostructures, consist of virtual hexagonal meshes with defects properly distributed in the intersectional areas. Currently, atomistic models are created mostly by hand, which is a notably tedious and time‐consuming process. In this paper, we develop a method that produces atomistic models automatically. Because a hexagonal mesh and triangulation represent dual graphs, our work focuses on the creation of proper triangulation. The edge lengths of the triangulation should be compatible with the lengths of the C–C bonds, and vertices with valences other than 6 (due to the defects in the hexagonal mesh) should be properly arranged around the boundaries of the different components of a carbon nanostructure. Two techniques play important roles in our method: (1) sphere packing is used to place the nodes for triangulation that produces nearly constant edge lengths of the triangles and (2) the movement and editing of defects is used to control the number and positions of the defects. We subsequently develop a computer program based on this method that can create models much easier and faster than the current handwork method, thereby reducing the operation time significantly. Copyright © 2016 John Wiley & Sons, Ltd.

Simple Robots with Minimal Sensing: From Local Visibility to Global Geometry

We consider problems of geometric exploration and self-deployment for simple robots that can only sense the combinatorial (non-metric) features of their surroundings. Even with such a limited sensing, we show that robots can achieve complex geometric reasoning and perform many non-trivial tasks. Specifically, we show that one robot equipped with a single pebble can decide whether the workspace environment is a simply connected polygon and, if not, it can also count the number of holes in the environment. Highlighting the subtleties of our sensing model, we show that a robot can decide whether the environment is a convex polygon, yet it cannot resolve whether a given vertex is convex. Finally, we show that by using such local and minimal sensing a robot can compute a proper triangulation of a polygon and that the triangulation algorithm can be implemented collaboratively by a group of m such robots, each with Θ(n/m) word memory. As a corollary of the triangulation algorithm, we derive a distributed analog of the well-known Art Gallery Theorem. A group of [n/3] (bounded memory) robots in our minimal sensing model can self-deploy to achieve visibility coverage of an n-vertex art gallery (polygon). This resolves an open question raised recently.

2A1-F23 A Simulation of CDMA Based Ultrasonic Localization System in a Large Scale Environment

This paper discusses a simulation platform for the faster localization method which enables simultaneous 3D multi-targets localization by using CDMA for the TOF measurement of ultrasonic signals. Signal from each transmitter is assigned a unique pseudorandom "Gold codes" so that receivers can recognize them even the signals are mixed. The system works in the Tran-MD mode in which mobile devices are designed to be transmitters and base stations are designed to be receivers. Ultrasonic transducer beam pattern and bandwidth, Multi-path problem and near-far effect, etc. are taken into the consideration in this simulation platform. Simulation results proved the accuracy and robustness of such localization method if the proper triangulation algorithm is applied.

Multiresolution model based extraction of product feature lines in reverse engineering

In this paper, multiresolution models are employed in the context of reverse engineering for feature line extraction. Starting with a proper triangulation of the cloud point data as a priori, our feature line extraction algorithm has three steps: (1) establishing a Gauss normal sphere and creating multiresolution models for the Gauss sphere based on different levels of subdivisions for the sphere regions; (2) mapping the unit normal vectors of triangular faces in the multiresolution Gauss sphere and merging those connected triangular faces whose unit normal vectors fallen on the same Gauss sphere region with a given resolution to form super-faces (the collection of triangular facets with similar normal); and (3) extracting the boundaries from the super-faces and generating the feature lines from the extracted boundaries. We then use these feature lines as a base for tracing boundary curves for B-spline surface construction. Since feature lines maintain the characteristics of the original product models, in this way, we have a good chance to reconstruct B-spline surfaces with high quality. Examples are given in the paper to show the feature line extraction, the influence of the feature lines extracted under different resolutions, and the final reconstructed B-spline surfaces based on these feature lines.

EMI analysis of finite sized image planes configuration using triangular patch model

Electromagnetic interference reduction using two layers of finite sized image planes is analysed by the method of moments based on the triangular surface patch model. It is demonstrated that proper triangulation should be made so as to take two basis functions in the boundary triangles of the surface.

Isoperimetric Quotient for Fullerenes and Other Polyhedral Cages

The notion of Isoperimetric Quotient (IQ) of a polyhedron has been already introduced by Polya. It is a measure that tells us how spherical is a given polyhedron. If we are given a polyhedral graph it can be drawn in a variety of ways in 3D space. As the coordinates of vertices belonging to the same face may not be coplanar the usual definition of IQ fails. Therefore, a method based on a proper triangulation (obtained from omni-capping) is developed that enables one to extend the definition of IQ and compute it for any 3D drawing. The IQs of fullerenes and other polyhedral cages are computed and compared for their NiceGraph and standard Laplacian 3D drawings. It is shown that the drawings with the maximal IQ values reproduce well the molecular mechanics geometries in the case of fullerenes and exact geometries for Platonic and Archimedean polyhedra.

On the Homotopy Type of Manifolds

1. The object of this note is to call attention to certain theorems, which follow very easily from some results due to E. Stiefel,' H. Seifert,2 Hassler Whitney,3 and myself.4 They refer to a class of manifolds which we call the class H, and are intended to throw light on the question, raised by W. Hurewicz,5 whether two closed manifolds of the same homotopy type are necessarily homeomorphic. The theorems depend both on M. H. A. Newman's6 theory of combinatorial equivalence, as re-developed by J. W. Alexander7 and carried further in S. S., and on theorems concerning differentiable manifolds. Therefore it is necessary to give a precise meaning to the term 'manifold'. By an n-dimensional manifold, M , we shall mean a class of combinatorially equivalent, simplicial complexes covering the same space, each complex being a formal manifold, meaning that the complement7 of each vertex is combinatorially equivalent to A or to A n-, according as the vertex in question is inside Mn or on Mn, where Ak stands for a closed k-simplex and Mn is the boundary of Mn. These covering complexes will be called proper triangulations of Mn (of course any simplicial complex covering Mn is a proper triangulation if the 'Hauptvermutung' is true). The proper triangulations of an unbounded manifold of class C', or smooth manifold, are to be Cl-triangulations.7a By a smooth, bounded, n-dimensional manifold we shall mean the manifold of which a sub-complex Ko C Kn is a proper triangulation, where Kn is a C' triangulation of a smooth, unbounded n-dimensional manifold and Ko is a formal manifold. By the topological product Mn X A k we shall mean the manifold having a normal subdivision of the cell-complex K n X A k as a proper triangulation where Kn is a proper triangulation of Mn. We shall use =to indicate combinatorial equivalence, and Mn Mn will mean that K Kn , where Ki is a proper triangulation of Mn .