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This study aims to present a new hybrid formulation based on non-uniform rational b-splines functions and enrichment strategies applied to free and forced vibration of straight bars and trusses.

Based on the idea of enrichment from generalized finite element method (GFEM)/extended finite element method (XFEM), an extended isogeometric formulation (partition of unity isogeometric analysis [PUIGA]) is conceived. By numerical examples the methods are tested and compared with isogeometric analysis, finite element method and GFEM in terms of convergence, error spectrum, conditioning and adaptivity capacity.

The results show a high convergence rate and accuracy for PUIGA and the advantage of input enrichment functions and material parameters on parametric space.

The enrichment strategies demonstrated considerable improvements in numerical solutions. The applications of computer-aided design mapped enrichments applied to structural dynamics are not known in the literature.

This paper aims to present an adaptive approach of the generalized finite element method (GFEM) for transient dynamic analysis of bars and trusses. The adaptive GFEM, previously proposed for free vibration analysis, is used with the modal superposition method to obtain precise time-history responses.

The adaptive GFEM is applied to the transient analysis of bars and trusses. To increase the precision of the results and computational efficiency, the modal matrix is responsible for the decoupling of the dynamic equilibrium equations in the modal superposition method, which is used with only the presence of the problem’s most preponderant modes of vibration. These modes of vibration are identified by a proposed coefficient capable of indicating the influence of each mode on the transient response.

The proposed approach leads to more accurate results of displacement, velocity and acceleration when compared to the traditional finite element method.

In this paper, the application of the adaptive GFEM to the transient analysis of bars and trusses is presented for the first time. A methodology of identification of the preponderant modes to be retained in the modal matrix is proposed to improve the quality of the solution. The examples showed that the method has a strong potential to solve dynamic analysis problems, as the approach had already proved to be efficient in the modal analysis of different framed structures. A simple way to perform h-refinement of truss elements to obtain reference solutions for dynamic problems is also proposed.

The purpose of this paper is to check the efficiency of isogeometric analysis (IGA) by comparing its results with classical finite element method (FEM), generalized finite element method (GFEM) and other enriched versions of FEM through numerical examples of free vibration problems.

Since its conception, IGA was widely applied in several problems. In this paper, IGA is applied for free vibration of elastic rods, beams and trusses. The results are compared with FEM, GFEM and the enriched methods, concerning frequency spectra and convergence rates.

The results show advantages of IGA over FEM and GFEM in the frequency error spectra, mostly in the higher frequencies.

Isogeometric analysis shows a feasible tool in structural analysis, with emphasis for problems that requires a high amount of vibration modes.

Realistic composite vehicles with 2, 3, 5 and 9 axles, consisting of a truck with one or two trailers, are addressed in this paper by computational models for vehicle–bridge interaction analysis.

The vehicle–bridge interaction (VBI) models are formed by sets of 2-D rigid blocks interconnected by mass, damping and stiffness elements to simulate their suspension system. The passage of the vehicles is performed at different speeds. Several rolling surface profiles are admitted, considering the maintenance grade of the pavement. The spectral density functions are generated from an experimental database to form the longitudinal surface irregularity profiles. A computational code written in Phyton based on the finite element method was developed considering the Euler–Bernoulli beam model.

Several models of composite heavy vehicles are presented as manufactured and currently travel on major roads. Dynamic amplification factors are presented for each type of composite vehicle.

The VBI models for compound heavy vehicles are 2-D.

This work contributes to improving the safety and lifetime of the bridges, as well as the stability and comfort of the vehicles when passing over a bridge.

The structural response of the bridge is affected by the type and size of the compound vehicles, their speed and the conservative grade of the pavement. Moreover, one axle produces vibrations that can be superposed by the vibrations of the other axles. This effect can generate not usual dynamic responses.

The purpose of this paper is devoted to present an accurate assessment for determine natural frequencies for uniform and non-uniform Euler-Bernoulli beams and frames by an adaptive generalized finite element method (GFEM). The present paper concentrates on developing the C1 element of the adaptive GFEM for vibration analysis of Euler-Bernoulli beams and frames.

The variational problem of free vibration is formulated and the main aspects of the adaptive GFEM are presented and discussed. The efficiency and convergence of the proposed method in vibration analysis of uniform and non-uniform Euler-Bernoulli beams are checked. The application of this technique in a frame is also presented.

The present paper concentrates on developing the C1 element of the adaptive GFEM for vibration analysis of Euler-Bernoulli beams and frames. The GFEM, which was conceived on the basis of the partition of unity method, allows the inclusion of enrichment functions that contain a priori knowledge about the fundamental solution of the governing differential equation. The proposed enrichment functions are dependent on the geometric and mechanical properties of the element. This approach converges very fast and is able to approximate the frequency related to any vibration mode.

The main contribution of the present study consisted in proposing an adaptive GFEM for vibration analysis of Euler-Bernoulli uniform and non-uniform beams and frames. The GFEM results were compared with those obtained by the h and p-versions of FEM and the c-version of the CEM. The adaptive GFEM has shown to be efficient in the vibration analysis of beams and has indicated that it can be applied even for a coarse discretization scheme in complex practical problems.

The purpose of this paper is to present an application of the Generalized Finite Element Method (GFEM) for modal analysis of 2D wave equation.

The GFEM can be viewed as an extension of the standard Finite Element Method (FEM) that allows non-polynomial enrichment of the approximation space. In this paper the authors enrich the approximation space with sine e cosine functions, since these functions frequently appear in the analytical solution of the problem under study. The results are compared with the ones obtained with the polynomial FEM using higher order elements.

The results indicate that the proposed approach is able to obtain more accurate results for higher vibration modes than standard polynomial FEM.

The examples studied in this paper indicate a strong potential of the GFEM for the approximation of higher vibration modes of structures, analysis of structures subject to high frequency excitations and other problems that concern high frequency oscillatory phenomena.

Despite its volume, the academic research on the impact of electronic word of mouth (eWOM) on tourism and hospitality consumer behaviour is fragmented and largely limited to investigating a small scope of its impact. The purpose of this paper is to bridge this gap by synthesising the existing literature, providing a conceptual framework for the various dimensions of this impact.

This paper is based on the meta-synthesis and a critical conceptual analysis of relevant academic literature identified using a keyword search of papers via the Web of Science and Scopus databases, followed by a snowballing process comprising tracking the citations to the resources referred to in the identified papers.

This conceptual analysis illustrates how the full spectrum of the impact of eWOM on tourist behaviour spans well beyond the limited scope traditionally focussed on by tourism and hospitality researchers. This scope, encompassing multiple cognitive, normative and affective dimensions, is illustrated in an evidence-based conceptual framework proposed in this paper, providing a systematic tool to identify the less-studied aspects of this important phenomenon.

This paper synthesises the large and fragmented body of literature on eWOM and proposes a novel conceptual framework, illustrating the vast scope of the various cognitive, affective and normative mechanisms through which eWOM affects consumers’ choice of tourism and hospitality products. Furthermore, this paper provides a synthesis of the state-of-the-art of research in this field, highlights the existing gaps and provides researchers with a systematic tool to identify pathways towards breaking the status-quo in progressing beyond the current boundaries of academic research in this field.

游客感知对清真旅游目的地的影响：结构模型分析

尽管有大量研究, 但有关网络口碑eWOM对旅游业和酒店业消费者行为的影响的学术研究仍是零散的, 并且在很大程度上只限于调查其影响的一小部分。本文的目的是通过综合现有文献来弥合这种差距, 为这种影响的各个方面提供概念框架。

本文基于元合成法和对相关学术文献的关键性, 概念性分析。这些文献是通过Web of Science和Scopus数据库对文章进行关键字搜索而确定的。随后是滚雪球式搜索过程, 该过程包括跟踪对已识别文章中引用的资源的引用。

这项概念分析阐述了eWOM对游客行为的影响范围如何远远超出了旅游和酒店业研究人员传统上关注的有限范围。这一范围是基于有理论依据的的概念框架提出的, 并涵盖多个认知, 规范和情感的维度。此范围为识别这一重要且缺乏研究的现象提供了系统的工具。

本文综合了有关eWOM的大量零散文献, 并提出了一个新颖的概念框架, 阐明了eWOM影响消费者选择旅游和酒店产品的各种认知, 情感和规范机制的范围。此外, 本文提供了该领域最新的研究综述, 突出了现有的差距, 并为研究人员提供了系统的识别打破现状的途径, 以超越当前学术界在这个领域的研究局限。

关键字 电子口碑, eWOM, WOM, 酒店, 旅游, 口碑

研究论文

El Boca a Boca Electrónico en el Comportamiento del Consumidor Turístico y Hotelero: Estado del Arte

A pesar del gran volumen de investigación académica sobre el impacto de eWOM en el comportamiento del consumidor turístico y hotelero, esta se encuentra fragmentada y en gran medida se limita a investigar un pequeño alcance de su impacto. El propósito de este artículo, es cerrar esta brecha sintetizando la literatura existente y proporcionando un marco conceptual para las diversas dimensiones de este impacto.

Este documento se basa en un análisis metasíntesis crítico y conceptual de la literatura relevante académica identificada, mediante una búsqueda de artículos por palabras claves a través de las bases de datos de Web of Science y Scopus, seguido de un proceso de “bola de nieve” que comprende el seguimiento de las citas de los recursos mencionados en los artículos identificados.

Este análisis conceptual, ilustra cómo el espectro total del impacto de eWOM en el comportamiento turístico se extiende mucho más allá del limitado alcance que tradicionalmente han realizado investigadores del turismo y hoteles. Este nuevo alcance, que abarca múltiples dimensiones cognitivas, normativas y afectivas, se ilustra en un marco conceptual basado en la evidencia propuesta en este documento, que proporciona una herramienta sistemática para identificar los aspectos menos estudiados de este importante fenómeno.

Este documento sintetiza la gran cantidad de literatura fragmentada sobre eWOM y propone un marco conceptual novedoso, que ilustra el amplio alcance de los diversos mecanismos cognitivos, afectivos y normativos a través de los cuales eWOM afecta la elección de los consumidores de productos turísticos y hoteleros. Además, este documento proporciona una síntesis del estado de la investigación en este campo, destaca las brechas existentes y brinda a los investigadores una herramienta sistemática para identificar vías para romper el statu quo en el progreso más allá de los límites académicos actuales en este campo.

Boca a boca electrónica, eWOM, WOM, Industria hoteleram, Turismo, Boca a boca

– Trabajo de investigación

Hospitals throughout the USA are facing increasing patient demand and employee shortages. This capacity issue has led to understaffing in some hospital areas. The purpose of this paper is to examine the understaffing in hospital-unit respiratory care and the impact to error rates, specifically missed treatments rates. The moderating effects of teamwork and standardized, integrated information systems are also considered.

Survey methodology is used for data collection of respiratory care managers within hospital units. Regression is used to test the hypotheses in this study.

The regression results show that higher rates of understaffing are associated with more missed treatments. In addition, both teamwork and integrated information systems are associated with lower missed treatments. Finally, the moderating effect of teamwork is also highly significant within the model while integrated information systems are not a significant moderator.

Managers working within understaffed hospital units can try to reduce missed treatment rates by both integrated information systems and teamwork among employees. Additional benefits can be gained from teamwork due to the indirect effects (moderating effects) as well. This indicates teamwork training can be useful for quality initiatives.

Understaffing is associated with higher missed treatments in hospital units. Standardized, integrated information systems within a hospital are associated with less missed treatments. Furthermore, employee teamwork within a hospital unit is associated with a direct effect on missed treatment rates as well as an indirect effect by weakening the negative impact of understaffing.

China’s experience of industrial growth is noteworthy for several reasons, not least because it has made a massive use of selective industrial policies. The industrial development guidelines set by the Five-Year Plans are extensively based on the choice of “strategic” or “pillar” industries to be promoted and supported. What remains unclear is the way in which such industries are identified among many. The purpose of this paper is to propose a debate on how to improve the government choice of strategic sectors and suggests a methodology to make this choice more transparent and rigorous.

The methodology allows ranking the different industries according to their strategic importance in the Chinese economy. The authors employ an uncertainty analysis methodology to verify the robustness of the ranking.

The results point to a list of strategic sectors for China. Comparing the ranking of the strategic sectors to the list of strategic priorities described in the Twelfth Five-Year Plan, we find that, by and large, the ranking coincides with the list of strategic sectors of the Chinese government.

The authors argue that improving the transparency and the rigor of the choice of pillar industries can be crucial for the Chinese government to maintain social legitimization in the transition to a “market” economy.

Very little is known about the choice of strategic sectors in China in the international literature. By addressing the debate on the choice of pillar industries in China, the paper discusses a topic scarcely studied offering a unique and original contribute.