Simplification Criteria Research Articles

A new high order hybrid WENO scheme for hyperbolic conservation laws

AbstractThis article proposes an improved hybrid weighted essentially non‐oscillatory (WENO) scheme based on the third‐ and fifth‐order finite‐difference modified WENO (MWENO) schemes developed by Zhu et al. in (SIAM J. Sci. Comput. 39 (2017), A1089–A1113.) for solving hyperbolic conservation laws. The MWENO schemes give a guideline on whether to use the WENO scheme or the linear upwind scheme. Unfortunately, because there is no explicit formula for computing the roots of algebraic polynomials of order four or higher, it is difficult to generalize this criterion to higher order cases. Therefore, this article proposes a simple criterion for constructing a series of seventh‐, ninth‐, and higher‐order hybrid WENO schemes, and then designs a class of improved smooth indicator WENO (WENO‐MS) schemes. Compared with the classical WENO schemes, the main advantages of the WENO‐MS schemes are their robustness and efficiency. And these WENO‐MS schemes are more efficient, have better resolution, and can solve many extreme problems without any additional techniques. Furthermore, a simplification criterion is proposed to further improve the computational efficiency of the WENO‐MS schemes, and these simple WENO‐MS schemes are abbreviated as WENO‐SMS schemes in this article. Extensive numerical results demonstrate the good performance of the WENO‐MS schemes and the WENO‐SMS schemes.

Basic theory of finite-type relations between orthogonal polynomial sequences

A theory of finite-type relations between two orthogonal polynomial sequences is developed. In fact, we find necessary and sufficient conditions for the extended connection coefficients which should be fulfilled for a finite-type relation. Next, a simplification criterion is given and some applications in the domain of continuous, discrete and quantum semiclassical orthogonal polynomials are treated into detail.

Common Transit Procedure and NCTS Implementation: the Case of Ukraine

The article analyses the EU policies towards the extension of a Common Transit Procedure and the New Computerised Transit System (NCTS) over associated countries given a case of Ukraine. A reasonable amount of the EU actions and aid on implementing the NCTS are performed within frameworks of the Eastern Neighbourhood Policy. It is instrumental for approximation of customs legislation, capacity budling, and modernization of customs authorities of the EU neighboring states. However, the impact of the NCTS implementation goes far beyond mere transit arrangements. It has the potential to introduce basic principles of the EU administrative law and best practices of administration into the day-by-day performance of national customs authorities. Ukrainian customs have favorable start conditions; so far, the national customs authorities and traders have experience in utilizing customs IT solutions. However, the transition to the new transit procedure may face specific issues due to disproportionately strict authorization criteria for transit simplification set by national legislation that exceeds the relevant rules of the EU legislation. Such restrictions cause low popularity of the new procedures harmonized with the EU legislation. Besides, in some cases, the approximation to the EU customs legislation results in discontinuing the existing simplification of customs procedures, which raises the question of possible distortions in the implementation of respective obligations and failure to share basic principles of good administration promoted by the EU.

Understanding rubric use in peer assessment of translation

ABSTRACT The present study adopted a process-oriented approach to investigate the efficacy of rubrics as a component of translation competence. In this study, 20 students performed an assessment of a Chinese-English translation. Subsequently, this group underwent a three-week rubric training program and were tasked to perform a second assessment of a similar Chinese-English translation. In both tasks the screen capture program, Camtasia was utilized to record each student’s assessment process. Based on the video recordings it was discovered that across the three rubric criteria (addition, simplification, reformulation), students visited the criterion of addition most frequently, and generated fewest but lengthiest comments. By comparison, they spent less time examining the criterion of simplification, though they produced more comments. This suggests that addition is more time-consuming than simplification to assess, yet more conducive to the assessors’ reflection. In addition, it was determined that after undergoing the training module, students showed early signs of rubric internalization, although their rubric mastery was clearly not fully automated. Specific pedagogical applications are thus suggested.

Survey on municipal sanitary licensing: procedures and simplification

Introdução: O licenciamento sanitário é o ato legal que permite o funcionamento de estabelecimentos que desempenhem atividades sujeitas à vigilância sanitária, sendo competência dos estados, do Distrito Federal e dos municípios. A publicação da RDC Anvisa nº 153, de 26 de abril de 2017, estabeleceu critérios nacionais para classificação de risco, simplificação e harmonização para o licenciamento sanitário. Objetivo: Obter informações sobre o processo de licenciamento sanitário adotado nos municípios brasileiros e avaliar a implementação e adoção dos critérios da RDC nº 153/2017 pelas Vigilâncias Sanitárias (Visa) municipais. Método: As informações foram obtidas por meio de um formulário virtual semiestruturado enviado por e-mail aos órgãos de Visa municipais. Resultados: Ao todo, 2.111 municípios enviaram informações acerca do conhecimento e da implementação da normativa, além dos procedimentos adotados para o licenciamento sanitário, tais como: momento de análise documental e inspeção sanitária, cobrança de taxa, tempo médio para concessão de licença sanitária, informatização e integração à Rede Nacional para a Simplificação do Registro e da Legalização de Empresas e Negócios (Redesim). Conclusões: Apesar de a normativa ser amplamente conhecida, apenas 15,4% dos órgãos de Visa municipais respondentes adotam procedimentos simplificados para concessão da licença sanitária para atividades econômicas até então denominadas de baixo risco. Além disso, ratificou-se a relevância estadual na coordenação das Visa municipais e, considerando a cobrança de taxa para emissão da licença sanitária pela maioria dos municípios brasileiros, verificou-se potencial impacto na arrecadação destes com a publicação da Lei da Liberdade Econômica. À Anvisa cabe a articulação com o Governo Federal e a proposição de programas que auxiliem a articulação entre os órgãos locais, para que promovam a troca de experiências, cooperação mútua e fortalecimento do Sistema Nacional de Vigilância Sanitária.

Map merging with terrain-adaptive density using mobile 3D laser scanner

Building 3D maps of various terrains is a necessary approach to gain environmental information for mobile robots when they are exploring in unknown territories. In this paper, we propose a method to construct a point cloud map with laser-measured data as the robot moves around. A terrain-adaptive density mapping technique is used to balance the demands of small data size and high terrain accuracy by utilizing the local curvatures as the simplification criteria. The adaptive density mapping technique is further integrated within the map merging framework to improve the matching speed and accuracy. Indoor and outdoor experiments are proceeded, which verifies the effects of using terrain-adaptive density point cloud on controlling the map size and decreasing the map alignment error.

An overview of generalization techniques for street networks

Generalization of 2D city layouts is a relevant operation common to Computer Graphics and GIS, whose goal is to generate simplified representations of street networks. However, most of the contributions in this area belong to the GIS literature, which we intend to bring closer to the CG community. In this paper we propose a threefold characterization of the algorithms dedicated to generic generalization and we also analyze the techniques proposed for the generation of personalized route maps in CG. We examine their data structures, simplification criteria and theoretical basis. To enable a comparative comprehension, we propose unified terminology and we refer the graphs used in the GIS literature to their name used in graph theory. From our analysis of the generalization techniques, we propose four research lines for further investigation to design new generalization algorithms, either from original ideas or by combining/extending some of the reviewed techniques.

Effect of Two Bogie Cavity Configurations on the Underbody Flow and Near Wake Structures of a High-Speed Train

A time-dependent simulation method, DES (detached eddy simulation), combined with Realizable k-ε turbulence model, has been adopted to study the underbody flow and near wake structures of a high-speed train with two bogie cavity configurations laid on the stationary ground. The numerical data, including time-averaged aerodynamic drag forces and pressure coefficients, were compared with experimental results from previous wind tunnel tests. A detail comparison of the instantaneous flow structures, mean velocity vector contours, velocity and pressure profiles under the train bottom in the symmetry plane and velocity contours overlaid with streamlines in the wake has been conducted in the two configurations. Also the aerodynamic drag coefficients for the two cases are discussed herein. The two cases show that the bogie cavity configurations contribute to the differences of velocity and pressure distributions in each bogie region, as well as the complex vortex structures around the bogie regions. Compared to the inclined bogie cavity configuration, the train with straight plates experiences a lower drag force by 2.8% for a three-car model in the stationary ground. Thus, an effective simplification criterion for the train model will contribute to an accurate prediction of forces of trains in simulations.

As retextualizações literárias no ensino de Português Língua Estrangeira. Resultados de uma primeira experiência

O projeto “Literatura no ensino de Português língua estrangeira” (LEPLE) estuda o lugar da literatura no nível inicial do ensino de Português Língua Estrangeira. A par da seleção de textos literários adequados aos níveis de Iniciação e Elementar (A1 e A2, respetivamente) do Quadro Europeu Comum de Referência para as Línguas (Conselho de Europa 2001), o projeto procede à retextualização de contos ou novelas que, por razões patrimoniais ou por manifesta interculturalidade, são relevantes neste contexto de ensino. Operando nos níveis A1 e A2, o processo de retextualização não se pode limitar à adaptação literária, pelo que a retextualização tomou como referência os critérios dos graded readers de longa tradição no espaço anglófono e os das escassas adaptações já feitas em Portugal. Face à exiguidade de material literário retextualizado no ensino de Português daqueles níveis, importa partilhar e discutir a experiência adquirida com a retextualização da novela O Senhor Ventura, de Miguel Torga (1943/1985), refletindo sobre os resultados da sua aplicação em diferentes contextos de ensino formal e das suas implicações na aferição dos critérios de retextualização.

A hybrid and automated approach to adapt geometry model for CAD/CAE integration

Traditional adaption of CAD geometry, which plays an important role in generating effective and fit-for-purpose finite element models, is usually carried out manually and optionally with excessive dependence on engineer’s experience. Automatic and efficient geometry modification before simulation evidently improves design efficiency and quality, and cuts down product life cycle. This paper represents an automatic approach to generate simplified and idealized geometry models for CAE simulation, which consists of hybrid model simplification criteria, feature-based model simplification, and simulation intent driven geometry modification. Hybrid adaption criteria takes detailed features geometric dimension, geometry topology, design intent into consideration synthetically. Simulation intent-driven modification with the help of virtual topology operators helps to deal with geometry at a higher level to get an ameliorative boundary for mesh without perturbing the original design model with constructing history for down-stream manufacture-oriented application, such as machining feature recognition and process planning. Development of plug-in toolkit guarantees automation of the simplification process and helps generate simulation-fitted geometry for subsequent analysis and simulation process. Prototype system and cases are implemented to demonstrate the result and efficiency of the proposed approach.

The Impact Of Architectural And Urban Patterns On The Behaviour Of An Exhibited Angular Size-Illusion

This paper continues a research in which it has been confirmed that the angular size-illusion underpins a contradictory effect related to a seeming size-decrease of focused architectural and urban objects as the observer approaches them. It explores the impact of various architectural and urban patterns on the behavior of an angular size-illusion noticeable during movement. To obtain sustainable conclusions, real locations are selected and simplified. Simplification criteria are defined respecting the preconditions necessary to trigger such an illusion. Also, two groups of parameters are formulated, both as illusion quantifiers and illusion qualifiers (such as descriptors and determinants). By analyzing the illusion quantifier’s conduct, the established valorization criteria allowed the methodological investigation of influences of illusion determinants on the descriptor’s behavior. The outputs-based conclusions are generalized in a form applicable to contemporary architectural and urban practice, making it possible to estimate and control the behavior of the illusion in reality. Keywords: architecture; angular size-illusion; illusion noticeability; illusion duration; illusion dynamics

A New Simplification Approach Based on the Oblique-Dividing-Curve Method for Contour Lines

As one of the key operators of automated map generalization, algorithms for the line simplification have been widely researched in the past decades. Although many of the currently available algorithms have revealed satisfactory simplification performances with certain data types and selected test areas, it still remains a challenging task to solve the problems of (a) how to properly divide a cartographic line when it is too long to be dealt with directly; and (b) how to make adaptable parameterizations for various geo-data in different areas. In order to solve these two problems, a new line-simplification approach based on the Oblique-Dividing-Curve (ODC) method has been proposed in this paper. In this proposed model, one cartographic line is divided into a series of monotonic curves by the ODC method. Then, the curves are categorized into different groups according to their shapes, sizes and other geometric characteristics. The curves in different groups will trigger different strategies as well as the associated criteria for line simplification. Whenever a curve is simplified, the whole simplified cartographic line will be re-divided and the simplification process restarts again, i.e., the proposed simplification approach is iteratively operated until the final simplification result is achieved. Experiment evidence demonstrates that the proposed approach is able to handle the holistic bend-trend of the whole cartographic line during the simplification process and thereby provides considerably improved simplification performance with respect to maintaining the essential shape/salient characteristics and keeping the topological consistency. Moreover, the produced simplification results are not sensitive to the parameterizations of the proposed approach.

When to warn – Update on interpretation of MEP

There are two types of intraoperative motor evoked potentials (MEPs): single-pulse spinal epidural D-waves and pulse train muscle responses. Amplitude criteria apply to D-waves because they resist anesthesia and exhibit 50% reduction because this correlates to long-term motor outcome. For peri-Rolandic brain surgery, the direct cortical stimulation D-wave warning criterion is >30% reduction. Muscle MEPs exhibit problematic variability and high sensitivity to anesthesia and central corticospinal pathway compromise. Disappearance is a major criterion because it correlates with postoperative weakness when irreversible. For IMSCT monitoring, marked (>80%) amplitude deterioration is an additional minor warning criterion. For other spinal cord monitoring, marked reduction can be an additional moderate warning criterion. For supratentorial, brainstem and facial nerve muscle MEP monitoring, >50% reduction is an additional major warning criterion. However, this depends on the degree of preceding trial-to-trial variability: when >50%, a larger decrement is needed; the reduction should be visually obvious and clearly exceed variability. Threshold elevation or morphology simplification criteria remain controversial.

Evolutionary based simplified symbolic PSRR analysis of analog integrated circuits

Parasitic interactions through the power supply lines put major limitations on the performance of analog amplifiers, especially in the mixed analog---digital integrated circuits. In this paper, a general method is presented for the symbolic analysis of power-supply rejection ratio (PSRR) in CMOS analog operational amplifiers. Since the complexity of the symbolic expressions grows exponentially with the circuit size, it is necessary to utilize simplification techniques for the analysis of practical circuits. We introduce an evolutionary criterion based on genetic algorithm for the efficient simplification of symbolic PSRR expressions. In contrast to the classical simplification criteria which simplify the different polynomials separately, the main advantage of the proposed criterion is to consider the correlation between different polynomials and different symbolic terms. The proposed methodology guarantees the accuracy of the simplified PSRR expressions in contrast to the exact ones, with a predictable error rate. Comparison of the numerical results extracted from the simplified symbolic PSRR expressions with HSPICE over two analog amplifiers demonstrates the efficiency of the proposed methodology. Simulations also show that the proposed evolutionary-based simplification technique outperforms the existing simplification criteria.

Graph-Based Simplification of Feature-Based Three-Dimensional Computer-Aided Design Models for Preserving Connectivity

The required level of detail (LOD) of a three-dimensional computer-aided design (3D CAD) model differs according to its purpose. It is therefore important that users are able to simplify a highly complex 3D CAD model and create a low-complexity one. The simplification of a 3D CAD model requires the application of a simplification operation and evaluation metrics for the geometric elements of the 3D CAD model. The evaluation metrics are used to select those elements that should be removed. The simplification operation removes selected elements in order to simplify the 3D CAD model. In this paper, we propose the graph-based simplification of feature-based 3D CAD models using a method that preserves connectivity. First, new evaluation metrics that consider the discrimination priority among several simplification criteria are proposed. Second, a graph-based refined simplification operation that prevents the separation of a feature-based 3D CAD model into multiple volumes is proposed. Finally, we verify the proposed method by implementing a prototype system and performing simplification experiments using feature-based 3D CAD models.

Automatic Simplified Symbolic Analysis of Analog Circuits Using Modified Nodal Analysis and Genetic Algorithm

In this paper, a hybrid methodology based on modified nodal analysis (MNA) and genetic algorithm (GA) is presented for simplified symbolic small-signal analysis of analog circuits containing semiconductor devices like MOSFETs. At first, the circuit is analyzed by the MNA, and the derived exact continuous-time transfer function is automatically simplified via GA. We propose a new multi-objective criterion for symbolic simplification of continuous-time transfer functions, which can be performed by such optimization algorithms as local-search algorithms, heuristic algorithms, swarm-intelligence algorithms, etc. In this paper, GA is used to validate the proposed simplification criterion. All processes including netlist text pre-processing, symbolic analysis via MNA, post-processing, and simplification via GA are consecutively run in an m-file MATLAB program. The comparison of obtained numeric results with HSPICE demonstrates the efficiency of the proposed methodology.

A Methodology for Automated Segmentation and Reconstruction of Urban 3-D Buildings from ALS Point Clouds

In this paper, a methodology which allows automated and efficient reconstruction of three-dimensional (3-D) geometric building models from an Airborne Laser Scanning (ALS) point cloud is introduced and its performance is analyzed and evaluated. The proposed method avoids abnormal and/or infinite solutions which are typically encountered in previously published methods that use the rooftop primitive adjacency matrix to solve the critical rooftop vertices. In particular, first, an improved random sample consensus (RANSAC) algorithm is proposed to segment the rooftop primitives, i.e., the planar patches that constitute rooftops, of each building or group of connected buildings. The algorithm successfully maintains topological consistency among primitives and avoids under- and over-segmentation with high efficiency. Second, a novel Voronoi-based primitive boundary extraction algorithm under constraints of outer and inner building boundaries is introduced in order to extract each primitive boundary. In this algorithm, the adjacent segmented primitive relationships among the various primitives are preserved by a subgraph of the Voronoi diagram so that the reconstructed neighbor primitives are seamlessly connected. Third, in order to refine the boundary shapes of primitives with irregular geometry, various criteria for making the boundary adjustments more effective are proposed. In this way, more regular 3-D buildings can be produced. Finally, the primitive boundary simplification criteria are formally introduced to generate compact 3-D building models. By using the simplification criteria, nonadjacency between neighbor primitives, intersection between boundaries, and self-intersections are, to a great extent, avoided. Numerous experimental results obtained using multiple data sets, including data from the cities of Toronto and Enschede as well as from the Niagara area, have shown that the proposed methodology has excellent performance and it can produce watertight 3-D polyhedral building models.

An evolutionary-based methodology for symbolic simplification of analog circuits using genetic algorithm and simulated annealing

In this paper, an evolutionary-based multi-objective criterion is introduced for simplified symbolic small-signal analysis of analog circuits containing MOSFETs. After circuit analysis via modified nodal analysis technique, the derived exact symbolic transfer function of the circuit behavior is automatically simplified. In contrast to traditional simplification criteria, the main objective of our criterion is to control the final simplification error rate. The proposed simplification methodology can be performed by such optimization algorithms as local-search algorithms, heuristic algorithms, swarm intelligence algorithms, etc. In this paper, a hybrid algorithm based on genetic algorithm and simulated annealing is applied to validate the proposed methodology. It is remarkable that all steps including netlist text processing, symbolic analysis, post-processing, simplification, and numerical analysis are consecutively derived in an m-file MATLAB program. The proposed methodology was successfully tested on three analog circuits, and the numerical results were compared with HSPICE.

Velocity-based adaptivity of deformable models

A new adaptive model for viscoelastic solids is presented. Unlike previous approaches, it allows seamless transitions, and simplifications in deformed states. The deformation field is generated by a set of physically animated frames. Starting from a fine set of frames and mechanical energy integration points, the model can be coarsened by attaching frames to others, and merging integration points. Since frames can be attached in arbitrary relative positions, simplifications can occur seamlessly in deformed states, without returning to the original shape, which can be recovered later after refinement. We propose a new class of velocity-based simplification criterion based on relative velocities. Integration points can be merged to reduce the computation time even more, and we show how to maintain continuous elastic forces through the levels of detail. Such meshless adaptivity allows significant improvements of computation time during simulations. It also provides a natural approach to coarse-to-fine deformable mesh registration.

Method to simplify ship outfitting and offshore plant equipment three-dimensional (3-D) computer-aided design (CAD) data for construction of an equipment catalog

The construction of an equipment catalog is necessary in ship outfitting and offshore plant design. We investigated the present status of equipment catalogs in shipyards and revealed several requirements for the catalogs, which are manually created and time-consuming. We defined the requirements by analyzing the construction procedure of the equipment catalog and conducted interviews with shipyard employees. In addition, problems with conventional equipment catalog construction are described, and a new procedure for the construction of an equipment catalog is introduced. By analyzing shipyard requirements, criteria for simplification (including volume, ports, and the outer boundary) are defined. Further analysis of technological factors for simplification is performed, and the results of implementing the simplification system are described. The proposed system is verified using three test cases used on site.