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The purpose of this paper is to develop a leakage model of metallic static seals, which can be used to accurately predict the leakage rate and study the corresponding seal characteristics. The metallic static seal is effectively applied to severe rugged environments where conventional seals cannot meet the needs. More research efforts for deepening the understanding of its seal characteristics are important for its effective and safe applications, of which the study about its leak is one key component.

In the microscopic observations of the turning surface that is general in the processing of flange surfaces, it is found that the spiral morphology is dominant, which had been also obtained by other researches. There are two potential leakage paths for the flange surface of spiral morphology, one is the radial direction perpendicular to the spiral ridges and the other is the circumferential direction along the spiral groove. Based on the microgeometry characteristics of spiral morphology, the micromorphology of turning flange surface is simplified for the calculation of leakage rate, and the simplified methods of the radial and circumferential leakage paths are presented separately. The topography of flange surface studied in this paper is actually measured, and the Abbott bearing surface curve is adopted to represent the micro-profiles parameters. The radial and circumferential leakage models are further developed based on the assumption of laminar flow of the viscous compressible gas.

The experiments used to verify the leakage models were carried out, and the experimental values are well agreed with the calculated values. As the contact pressure increases, the change rules of both radial and circumferential leakage rates are obtained and the obvious transition from radial leak to circumferential leak can be found. Using the proposed leakage models, the effects of the key micro-profiles parameters on the leakage rates are studied, and some specific conclusions are given simultaneously, which are favorable for the theoretical study and practical application of the metallic static seal.

By the interpretations of the micromorphology characteristics of turning flange surface, the leakage mechanism of the metallic static seal is further made clear. The proposed leakage model reveals the relationships between the key micro-profiles parameters and some sealing performances about the leakage and can predict the leakage rates of the metallic static seal used in various working conditions.

For the metallic static seal, the simplification of the radial leakage path and the radial leakage model are put forward for the first time, so the total leakage model can be systematically reported based on the micromorphology characteristics of turning flange surface. The effects of the key micro-profiles parameters on the seal behaviors including of the leak rate, critical contact pressure and transition from radial leak to circumferential leak etc are also clarified firstly.

This paper aims to examine the recent evolution of the regulation of statutory auditing since the passage of the Sarbanes-Oxley Act of 2002 in the USA by comparing the regulatory structures for auditing in the USA, France and Canada.

Using publicly available documents, the paper seeks to understand how the regulatory structures for statutory auditing have changed in the period since the passage of the Sarbanes-Oxley Act. The USA, France and Canada were chosen for analysis because prior to Sarbanes-Oxley the regulatory structures of these three countries were relatively distinct, whereas subsequent to the Act they appear to be becoming similar.

The authors interpret the increasing apparent similarity in the regulatory structures for statutory auditing in these three countries to be the result of external pressures from global capital markets for standardized regulatory practices. However, this apparent similarity may also be a form of “decoupling”, whereby actors in the institutional field of professional regulation, under pressures from powerful external forces, seek to enhance their legitimacy while maintaining internal flexibility and a certain capacity for resistance against external pressures in the institutional field.

The paper relies on a qualitative analysis of regulatory structures based on a review and analysis of publicly available documents and legislation. As such, it has limitations similar to other qualitative studies.

The regulation of statutory auditing is important to society both to assure the proper functioning of capital markets and to provide reliable information to the general public. Gaining a better understanding of the regulatory structures for statutory auditing advances the public interest.

There have been few prior research efforts that have examined the regulation of statutory auditing through the lens of new institutional theory.

This paper aims to investigate the effects of descent time spent with flaps extended on fuel burn (FB) and specific range for five different flight path angles (FPAs) ranging between 2.0° and 4.0° for a commercial aircraft.

A large data set of actual flight data (n = 475) of the same type of a frequently used commercial aircraft were investigated by using statistical methods.

The result of the comparison of the highest and the lowest FBs of flight profiles for each FPAs present that the fuel saving was achieved by keeping at as a high airspeed as possible and deploying flaps as late as possible, which is in line with the objective of delayed deceleration approaches. From analyzing the flight profiles, it was proven that delaying deceleration and also descending without flaps or with flap over a shorter time resulted in less FB of 101.1, 70.9 and 94.9 kg for FPA 2.5°, FPA 3.0° and FPA 3.5°, respectively.

This study differs from prior studies because it focused on the effects of the different vertical profiles on FB. Also, the use of real flight data recorder data in the analysis presents the originality of this study.

The purpose of this paper is to analyze the tourist landscape as represented in Turisme de Barcelona’s YouTube tourism promotional videos, looking at the landscape’s tangible locations, symbolic and tourist assets and the protagonists in an effort to interpret its storytelling in an overtourism context.

The mixed methodology is based on a visual content analysis of promotional videos posted on the official Barcelona tourism YouTube channel. Quantitative data analysis about the assets and their localization was completed with a qualitative assessment of the way these assets are displayed to unveil the narrative they convey.

The results highlight that Barcelona’s projected image is mainly based on tangible heritage (especially monuments), its recognizable cityscape and its eno-gastronomic assets. This rather conventional image is geographically concentrated on the neighborhoods perceived as tourist neighborhoods.

This analysis provides a critical reflection of the actual strategy of destination management organizations and the storytelling they transmit. The findings can help to orientate their future actions and provide a method of analysis that can be repeated for other destinations.

This paper sheds new light on the use of urban landscapes in nonstatic images both as a narrative subject and as a tangible tourist space in promotional discourse.

Le tourisme peut revêtir des formes très diverses et on peut le subdiviser en de multiples catégories en prenant comme critère le motif du voyage, la durée du séjour, la provenance du voyageur, etc. Estil utile pour l'analyse du tourisme de faire des subdivisions en partant du mode de transport utilisé par le voyageur et de parler de tourisme ferroviaire, aérien, maritime ou routier? On peut répondre affirmativement à cette question pour autant que le moyen de transport employé ait une influence considérable sur l'extension du tourisme ou sur la manière de voyager ou d'organiser son séjour.

This paper reviews literature on the application of intelligent systems in the libraries with a special issue on the ES/AI and Robot. Also, it introduces the potential of libraries to use intelligent systems, especially ES/AI and robots.

Descriptive and content review methods are applied, and the researchers critically reviewed the articles related to library ESs and robots from Web of Science as a general database and Emerald as a specific database in library and information science from 2007–2017. Four scopes considered to classify the articles as technology, service, user and resource. It is found that published researches on the intelligent systems have contributed to many librarian purposes like library technical services like the organization of information resources, storage and retrieval of information resources, library public services as reference services, information desk and other purposes.

A review of the previous studies shows that ESs are a useable intelligent system in library and information science that mimic librarian expert’s behaviors to support decision making and management. Also, it is shown that the current information systems have a high potential to be improved by integration with AI technologies. In this researches, librarian robots mostly designed for detection and replacing books on the shelf. Improving the technology of gripping, localizing and human-robot interaction are the main concern in recent librarian robot research. Our conclusion is that we need to develop research in the area of smart resources.

This study has a new approach to the literature review in this area. We compared the published papers in the field of ES/AI and robot and library from two databases, general and specific.

The price of a painting is determined by multiple variables, including color-related variables. Colors are important in an economic analysis. This study aims to analyze the paintings executed by Jean-Michel Basquiat (the famous street artist from the 1980s' New York City) and sold at auction to study the potential effect of color intensity, luminosity and color contrast on the prices of his paintings. The authors also study the case of the op art master, Carlos Cruz-Diez, as a robustness analysis to the main results. The analysis that the authors present may be of interest to academicians and to participants in the art market.

The authors run a hedonic regression model considering 306 paintings (executed by Basquiat alone), and 41 works painted collaboratively between Basquiat and Warhol and sold at auction (2003–2017). The data and the images corresponding to each painting were hand-collected from the websites of several auction houses and complemented with information obtained from the Artprice and Blouin websites.

Increases in color intensity, luminosity and color contrast have a positive effect on art prices. The authors also find that color intensity is even more recognized (as reflected by higher prices) for paintings belonging to Basquiat's most appreciated (understood as most expensive) artistic period (1980–1983) and during the second part of the sample period (2011–2017). The authors find similar results for Cruz-Diez. The authors also estimate that Basquiat's artworks made collaboratively with Andy Warhol are worth 55% less than those made only by Basquiat. An investment in Basquiat's paintings generated an average annual compounded return of 16.81% (2003–2017), clearly overperforming the S&P 500.

The main limitation of the hedonic regression method lies in the need to have a significant and varied sample to identify the true effect of each variable on the price of the good. Another limitation is that we are only able to use art prices from auctions, as this is the only comprehensive source of data that is publicly available. These two limitations are common to all studies that use the hedonic pricing model. This paper has implications not only for the art pricing (and more generally, asset pricing) literature, but also for the fields of psychology and marketing.

This is the first paper that highlights the importance of analyzing the price impact of color intensity throughout the artistic periods of a painter, finding that color intensity is even more appreciated (as reflected by higher prices) for paintings belonging to an artist's most recognized period. In the case of color contrast, the authors present a novel way to estimate this variable.

El precio de una pintura está determinado por múltiples variables, incluidas las relacionadas con el color. Los colores son importantes en el análisis económico. En este trabajo, se analizan las obras realizadas por Jean-Michel Basquiat (el famoso artista callejero latino de la escena artística neoyorquina de los años 80) y vendidas en subasta, para estudiar el efecto potential que la intensidad del color, la luminosidad y el contraste de sus pinturas pueden tener sobre sus precios También estudiamos el caso del maestro de op-art, Carlos Cruz-Diez, como análisis de robustez a nuestros principales resultados. El análisis que presentamos puede ser de interés tanto para académicos como para participantes del mercado del arte.

Realizamos un modelo de regresión hedónica considerando 306 obras (pintadas solo por Basquiat), y 41 obras realizadas de manera colaborativa entre Basquiat y Warhol y vendidas en subasta (2003–2017). Los datos y las imágenes correspondientes a cada obra fueron recolectados a mano de los sitios web de varias casas de subastas y complementados con información de los sitios web de Artprice y Blouin.

Incrementos en la intensidad, luminosidad y contraste del color (variable para la que proponemos una nueva medida), inciden positivamente en los precios del arte. También encontramos que la intensidad del color es aún más reconocida (como se refleja en los precios más altos en las subastas) para pinturas pertenecientes al período artístico más apreciado de Basquiat (1980–1983), entendido como el más caro, y durante la segunda parte del período muestral (2011–2017). Además, hallamos resultados similares para Cruz-Diez. De igual forma, estimamos que las obras de arte de Basquiat realizadas en colaboración con Andy Warhol valen un 55% menos que las realizadas solo por Basquiat. Una inversión en las pinturas de Basquiat generó un rendimiento compuesto anual promedio del 16,81% (2003–2017), claramente superando el rendimiento total del índice S&P 500.

La principal limitación del método de regresión hedónica radica en la necesidad de contar con una muestra significativa y variada para identificar el verdadero efecto de cada variable sobre el precio del bien en estudio. Otra limitación consiste en que solo es posible utilizar los precios de las obras de arte que son vendidas en subastas, ya que esta es la única fuente completa de datos que está disponible públicamente. Estas dos limitaciones son comunes a todos los estudios que utilizan el modelo de precios hedónicos. El artículo tiene implicaciones no solo para la literatura sobre precios de arte (y, más en general, sobre los precios de los activos), sino también para la literatura sobre psicología y mercadeo, en donde el estudio del impacto de los colores en las emociones y en el atractivo de un producto son de suma importancia.

Este es el primer estudio que destaca la importancia de analizar el impacto en precios de la intensidad del color a lo largo de los períodos artísticos de un pintor, debido a que se determinó que la intensidad de color es aún más apreciada (como se refleja en los precios más altos en las subastas), para las pinturas pertenecientes al período artístico más reconocido de un artista. En el caso del contraste de color, se propuso y utilizó una forma novedosa de estimar esta variable.

Barbados is at a very advanced stage of population aging. Health care services are designed to ensure universal access for all Barbadians but the contributing factors for older adults’ health care utilization are not well explored. This chapter examines gender differences in the correlates of seeking medical care among older adults in Barbados.

Logistic regression models were applied to data drawn from the 2000 Survey of Health, Well-Being and Aging of Older Adults in Latin America and the Caribbean (SABE), Bridgetown sample (n = 1,068).

Health needs, based on chronic conditions, were positively associated with seeking medical care for men and women. Different forms and directions of intergenerational support were associated with men and women seeking care. Among men, receiving financial support was positively associated with seeking care. Among women, providing financial support was associated with lower odds of seeking care while receiving instrumental support was associated with higher odds of seeking care.

Medical care is only one form of health care use and there is no specification of the nature of care or consultation. The sample is cross-sectional and limited to older adults in urban areas. The relative importance of enabling factors and health needs, especially, may differ across time and space within Barbados.

The study contributes to the literature on health care utilization among older adults within developing countries and highlights the pertinence of family relations influencing gender differences in health care utilization.

Family holiday decision-making (FHDM) is a process composed of several stages. This paper aims to describe two objectives: to identify at each stage the roles in couples, the main decision-maker in the case of family holidays; and to determine the most influential variables.

To identify the roles played by the partners, a frequency analysis has been conducted, which provides a graphic representation of the so-called feasibility triangles. The technique selected to identify the variables that explained the decision structure was binary logistic regression. In total, 375 useful dyads of questionnaires were received.

Holidays follow a joint decision-making process in the initiation phase and in the final decision, while the search for information is carried out equally by either partner. The woman’s work situation, the type of destination travelled to and the difference in education levels between them are the variables that best explain how couples decide on their family holidays.

A better understanding of the FHDM process will help tourism companies to improve their marketing campaigns.

The characteristics of the sample composed of 375 couples whose members completed a questionnaire separately have allowed not have to rely on one response per household, which adds reliability to the results. This sample is higher than the one of many reference publications on the subject. Furthermore, this paper revealed differences between male and female perception.

This study aims to examine how the organizational structure of arts groups and their administrative personnel’s socio-demographic attributes affect the working conditions of and create tensions for their staff. Recent discussion about the cultural industries and labor has pursued two strands – macro-level research expounds on the organization of cultural industries and labor market; and micro-level studies focus on the work and employment of cultural practitioners. Very few of them, however, articulate the relationships between the two levels. This study contributes to the literature with a multilevel framework that examines the interplay between the structural conditions and personal factors in which labor–capital relationships evolve.

This study applies a qualitative approach to collect and analyze data. It conducted 39 in-depth interviews with arts managers and administrators from a sample of 18 performing arts organizations across four performing arts sectors in Hong Kong, namely, drama, music, dance and opera. The stratified sample covers arts organizations of different funding models – the public “nationalized” form, the mixed-economy form, and the privatized form.

This study shows that the funding and organization model of arts organizations resulted in various forms of job structure, and that the practitioners’ socio-demographic background shapes their career expectations. The job structure and career expectations together affect the labor turnover and influence organization strategies.

This study’s methodological contribution lies on its application of a multilevel framework to analyze the relationships between the macro- and the micro-level factors underpinning the working conditions of labor in the cultural industries. Besides, it contributes to the discussion about “labor precariousness” with empirical evidence from a comparative study of arts managers and administrators from organizations across four performing arts sectors.