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This paper aims to compare different dynamical models, cavitation procedures and numerical methods to simulate hydrodynamic lubricated bearings of internal combustion engines.

Two dynamical models are considered for the main bearing of combustion engines. The first is a fluid-structure interaction multi-body dynamics coupled with lubricated bearings, where the equilibrium and Reynolds equations are solved together. The second model finds the equilibrium position of the bearing subjected to previously calculated dynamical loads. The Traditional p-? procedure and Giacopini’s model described in Giacopini et al. (2010) are adopted for cavitation purposes. The influence of the finite difference and finite element numerical methods is investigated.

Simulations were carried out considering small-, mid- and large-sized engines and the dynamical models differed mainly in predicting the journal orbits. Finite element method with Giacopini’s cavitation model had improved numeric stability for the three engines.

The dynamic models do not consider the flexibility of the components of the main mechanism of combustion engines which may overestimate the oil pressure and journal orbits.

It can help researchers and engineers to decide which combination of methods is best suited for their needs and the implications associated with each one.

The used methods may help engineers to design better and more efficient combustion engines.

This paper helps practitioners to understand the effects of different methods on the results. Additionally, depending on the engine, one approach can be more effective than the other.

This paper presents some linear adaptive non‐nested multigrid methods which are applied to linear elastic problems discretized with triangular and tetrahedral finite elements using unstructured and Delaunay mesh generators. The Zienkiewicz‐Zhu error estimator and a h‐refinement procedure are used to obtain the non‐nested meshes used by the multigrid methods. We solve problems with a specified percentage error in the energy norm using the optimal performance of multigrid methods.

Presents the development of object‐oriented finite element classes based on the concept of parameterized types of templates of the C++ programming language. Two parameter array classes were implemented which are used extensively in other classes. The implementation was simple, resulting in a set of manageable, efficient and simple C++ finite element classes. Initially, object‐oriented programming concepts, C++ templates and template array classes are presented. The finite element classes and some examples using those classes are also discussed.

This paper aims to numerically investigate the surface texturing effects on the main bearings of a three-cylinder ethanol engine in terms of the power loss and friction coefficient for dynamic load conditions.

The mathematical formulation considers the Partir-Cheng modified Reynolds equation. The mass-conserving Elrod-Adams p-θ model with the JFO approach is used to deal with cavitation. A fluid-structure coupling procedure is considered for the elastohydrodynamic lubrication. Accordingly, a 3-D linear-elastic substructured finite element model obtained from Abaqus is applied

Simulations were carried out considering different dimple texture designs in terms of location, depth and radius. The results suggested that there are regions where texturing is more effective. In addition, distinct journal rotation speeds are studied and the surface texture was able to reduce friction and the power loss by 7%.

The surface texturing can be a useful technique to reduce the power loss on the crankshaft bearing increasing the overall engine efficiency.

The surface texturing performance in a three-cylinder engine using ethanol as fuel was investigated through numerical experimentation. The results are supported by previous findings.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-09-2019-0380/

The purpose of this paper is to investigate the academic side of university–firm linkages, reporting the results of research (called the “BR Survey”, a primary database) conducted in Brazil with leaders of research groups that interacted with firms. The authors analysed the answers from 662 research groups (from both universities and research institutes) to investigate whether the intensity of private funds affects the results of the interactions. The main intent is to answer the following question: Is there a difference between funding sources and the type of results achieved by research groups when interacting with firms?

To verify the impact of some variables on the perception of the main results of university–firm interactions, highlighting the impact of funding sources, the authors present a Logit Model defined with binary dependent variables. The null value is categorized as a “scientific result” (new scientific discoveries and research projects; publications, theses and dissertations; human resources’ and students’ education) and the value 1 is classified as an “innovative/technological result” (new products, artefacts and processes; improvement of industrial products and processes; patents, software, design and spin-off firms).

The authors found that the modes of interaction (relationship types) and some knowledge transfer channels, besides the number of interactions with firms, have statistically significant coefficients, so their values present different impacts on the results of the interaction. The results suggest that the Brazilian innovation policy towards a more active and entrepreneurial role of universities is fostering innovative/technological results from university–firm interactions.

The originality of the study lies on the results found that given the fact that private funding sources do not affect the conventional mission of Brazilian universities – teaching and research – university research groups should be even more incentivized to search for private funds to carry out their research. This may be a solution to the public fund scarcity and may help in reducing the historical distance between universities and firms in Brazil.

The purpose of this paper is to evaluate the efficiency in financial intermediation and the cost efficiency in banking service of credit unions in Brazil, based on essentially accounting variables, and to analyze the temporal evolution of the efficiency of these cooperatives.

With a sample of 315 cooperatives over the period from 2007 to 2014, this research uses a two-stage process: application of regression models with panel data to verify which variables are related to the defined outputs, with the reduction of 31 variables to 8 variables in both models; and application of the data envelopment analysis method to obtain an analysis of credit unions’ efficiency.

The results demonstrate a high level of efficiency in financial intermediation, with low variation over time, associated with a low efficiency in the banking service, in which few cooperatives have remained efficient over time. In addition, the cooperatives with highest efficiency in financial intermediation were also the most efficient in providing services.

This research has some limitations about the capacity of the proxies used to capture the real effect of the variables and assumptions of economic relations resulting in restrictions to generalize the results.

Cooperatives are usually analyzed under just one dimension. By separating the analysis into financial intermediation and banking services, cooperatives that are more efficient in each dimension can be identified, in addition to analyzing the evolution over time. The authors found that efficiency tends to be lower in banking services, and few cooperatives remain at the highest level of efficiency over time in both models.

Credit unions provide an important service in the banking and credit market. Therefore, understanding its operation and the characteristics that influence its efficiency allows a better management of the cooperatives themselves and a greater understanding of this important segment of the financial market.

Visitor attractions constitute the essence of the tourism phenomenon. However, management techniques that are expressly designed for tourism and develop different uses/activities and subsequently influence visitor experiences are under-researched. Hence, the purpose of this study is to develop a conceptual framework that provides a bridge between on-site management, visitor attraction development and visitor experience by introducing a novel concept: “usability of visitor attractions.” This new concept captures how managers can develop uses for visitors to experience the attraction. Thus, this study explores this concept and serves as the foundation for further research on this topic.

The systematization of the state of the art is based on an exhaustive desk research review of both academic and grey literature to endorse the “usability of visitor attractions” concept.

The literature review reveals that visitor attraction management affects visitor experience. To succeed, managers should consider the ease of use and the design of activities. Therefore, an innovative conceptual model is built to explore how on-site management techniques based on this new concept impact on visitor’s experience.

Research on visitor experience in attractions has neglected the impact of on-site management tools hitherto. Therefore, the originality of the study lies on providing a robust framework that enlightens how visitor attraction management affects visitor experience by developing the usability. The study proposes a novel concept and an original model that will be of a critical interest to tourism academia and will serve as practical guidance for attraction managers.

旅游景点构成了旅游现象的本质。然而, 专门为其开发不同用途/活动并随后影响游客体验的管理技术仍处于起步阶段。因此, 本文的目的是通过引入一个新的概念：旅游景点的可用性来建立一个概念框架, 搭建现场管理、旅游景点开发和游客体验之间的关系桥梁。这一新概念描述了管理者如何开发游客体验景点的可用性。因此, 本文探讨了这一概念并以为未来旅游学术界对本主题感兴趣的相关研究奠定基础。

研究前沿的分类是基于详尽学朮和灰色文献的书面材料审查来背书 “旅游景点的可用性” 这一概念。

文献综述表明, 旅游景点管理影响游客体验。为达成这一目的, 管理者应该考虑景点使用的便利性和活动的设计。因此, 我们建立了一个创新的概念模型来探讨基于这一新概念的现场管理技术对游客体验的影响。

本文的创新之处在于提供了一个稳健的框架, 揭示旅游景点可用性通过景点管理进而影响游客体验。本文建议一个新的概念和原本的模型将为旅游景点管理者提供实际指导。

Los atractivos turísticos constituyen la esencia del fenómeno turístico. No obstante, las técnicas de gestión y planificación diseñadas expresamente para desarrollar diferentes usos/actividades en los atractivos, que posteriormente influyen en la experiencia de los visitantes, han sido escasamente investigadas. Por ello, el propósito de esta investigación radica en elaborar un marco conceptual que integre la gestión del atractivo, el progreso del mismo y la experiencia del visitante mediante la introducción de un concepto novedoso: “la usabilidad de los atractivos turísticos”. Este nuevo concepto enfatiza la manera en que los gestores pueden implementar diferentes usos en los atractivos, proporcionando a los visitantes diversas experiencias. Por tanto, esta investigación explora el concepto y sirve como fundamento para futuras investigaciones.

La metodología se basa en una exhaustiva revisión de la producción científica y de informes de organismos públicos para respaldar el concepto de “usabilidad de los atractivos turísticos”.

La literatura examinada revela que la gestión de los atractivos afecta en la experiencia de los visitantes. Así pues, los gestores deben considerar en concreto la facilidad de uso y el diseño de actividades. De este modo, un modelo conceptual innovador ha sido construido para explorar cómo las técnicas de gestión basadas en este nuevo concepto tienen un impacto en la experiencia del visitante.

La investigación sobre la experiencia del visitante en los atractivos ha descuidado el impacto de las herramientas de gestión y planificación hasta ahora. Consecuentemente, la originalidad de esta investigación radica en proporcionar un marco robusto que señala cómo la gestión de los atractivos afecta en la experiencia del visitante mediante el desarrollo de la usabilidad. El estudio propone un concepto novedoso y un modelo original que se considera de gran interés para el ámbito científico, y al mismo tiempo, puede servir de guía práctica para los gestores de los atractivos turísticos.

Firms are the primary producers of innovations, and understanding how these agents acquire, update and manage the knowledge of their employees is central to understanding economic growth. However, in developing economies, technology adaptation plays a critical role in innovation compared to knowledge creation. Thus, this research investigates the role of human capital in innovation at the firm level in the case of a small developing economy, which ranks highly on several human capital dimensions but shows declining levels of investment in advanced human capital development in its manufacturing sector.

This research examines the relationship between innovation and human capital at the firm level in a small peripheral economy. The human capital theory is applied to a firm context to understand variations in innovative behavior depending on the size of manufacturing companies. The effect of several human capital dimensions on product innovation is estimated by applying binomial logistic regression models with firm and time-fixed effects.

This article contributes to innovation economics and public policy by highlighting that not all dimensions of human capital operate similarly for all companies in the context of developing economies. In such settings, technology adaptation plays a critical role in innovation. While employees' human capital endowments significantly impact small firms in that context, firm-level practices such as internal training are crucial for large companies. Consequently, policymakers should consider that firms' human capital endowments impact their innovative behavior differently to avoid one-size-fits-all policy design approaches in this regard.

Prior research on the relationship between human capital and innovation in developing economies was based on a cross-sectional approach. This research's unique panel dataset covering 11-year triennial innovation surveys enabled a modeling strategy that controls for time-invariant unobservable firm characteristics. Three aspects of firms' human capital have been analyzed human capital endowments, internal training and human resource management (HRM) practices for the first time longitudinally in a developing economy, enabling to contrast of empirical findings with policy design.

Okara, which is the residue of hydrosoluble extract from soybean obtained after soymilk and tofu production, has high nutritional value and can be used for ingredient in specific food products. This study aims to evaluate the production and properties (physicochemical, microscopical and functional ones) of okara flour (OF) obtained from okara as a by-product of soymilk and tofu production.

Wet okara resulted from the soymilk process underwent convective drying up to reach mass stability (60°C for 12 h). OF properties were analyzed by official methods by AOAC, i.e. mineral composition was evaluated by atomic absorption equipment; color; water absorption index (WAI); milk absorption index (MAI); oil absorption capacity (OAC); and foam capacity (FC) required mixtures with water, milk and oil, separation and gravimetry, respectively; and microstructure was determined by a scanning electron microscope.

Results showed the potential OF has as a source of protein (24.74 g/100 g) and dietary fiber (58.27 g/100 g). Regarding its color after the drying process, OF was markedly yellow (b* parameter 20.16). Its WAI was 3.62 g/g, MAI was 4.33 g/g, OAC was 3.68 g/g and FC was 1.32 per cent. The microscopic analysis of OF showed that both loose and agglomerated particles had irregular structures and indefinite forms.

Production of flour from wet okara can be an alternative use of this by-product. This study showed important characteristics of OF and its possible application to the food industry. Thus, OF was shown as a potential ingredient with high nutritional value.