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Article
Publication date: 3 May 2013

Liang Yan‐ping, Yu Hong‐hao and Bian Xu

The purpose of this paper is to introduce an analytic method to calculate the slot leakage reactance of stator bar strands in alternative current machines whose stator windings…

Abstract

Purpose

The purpose of this paper is to introduce an analytic method to calculate the slot leakage reactance of stator bar strands in alternative current machines whose stator windings have multiple bars per layer and using deficient transposition.

Design/methodology/approach

Based on the analysis of deficient transposition, the calculation model of mutual slot leakage reactance between any two strands in one bar is established. The subsection integral method is presented to calculate the slot leakage reactance and analytic function is listed. A pump motor used in nuclear power is taken as an example, and the slot self leakage reactance of any strand in its top layer winding and the slot mutual leakage reactance between one strand and other strands in the same bar are calculated depending on the method described above. The slot leakage reactance of all strands in the top layer winding is calculated when different transposition angles are applied in stator bars.

Findings

The results show that subsection integral method is effective in calculating the slot leakage reactance of stator bar strands of deficient transposition. The slot leakage reactance distribution of all strands is obtained. The transposition angle has a great impact on the slot leakage reactance distribution of stator bar strands.

Originality/value

This paper presents an available method to calculate the slot leakage reactance of any strands in alternative current machine whose stator windings have multiple bars per layer and using deficient transposition, and discusses the impact of transposition angle on the slot leakage reactance. The conclusion can lay the foundation of the effective calculation of circulating current losses in stator bars with deficient transposition.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 32 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 October 2004

Alvaro Valencia and Williams Calderón

Flow structure and convective heat transfer in a plane channel with in‐line mounted rectangular bars have been investigated for different bar sizes in the Reynolds number range…

Abstract

Flow structure and convective heat transfer in a plane channel with in‐line mounted rectangular bars have been investigated for different bar sizes in the Reynolds number range corresponding to steady laminar flow to unsteady transitional flow. Numerical results are reported for the thermal entrance region with six in‐line mounted bars and for the case with spatially periodic mounted bars. Data for heat transfer and pressure drop are presented for 100≤Re≤1,000 and bar heights 0.24≤d/H≤0.48. The unsteady Navier‐Stokes equations and the energy equation have been solved by a finite‐volume code with staggered grids combined with SIMPLEC pressure correction. Flow and heat transfer characteristics in the different rows are strongly dependent on Re and d/H. The flow structure and temperature field around the sixth row are compared qualitatively well with those calculated with periodic boundary conditions, however, the comparison of mean Nusselt number and friction factor shows differences for high Reynolds numbers.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 14 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 May 1990

Pari Boustani and Vincent‐Wayne Mitchell

A decade of growth in the health food market is typified by thecase of cereal bars. They have undoubtedly benefited from an increasedconsumer awareness about healthier ways to…

Abstract

A decade of growth in the health food market is typified by the case of cereal bars. They have undoubtedly benefited from an increased consumer awareness about healthier ways to eat, but to what extent do consumers perceive these bars to be the “healthy alternative snack”, and how healthy are they? The results of a consumer survey (n=200) are reported which suggests that cereal bars are perceived as being healthy. Chemical analysis revealed that on sugar, fat, salt and fibre content, these bars were only marginally better than favourite traditional snacks. Sensory analysis showed that consumers much preferred cereal bars which contain chocolate but that these were not the healthiest. The gap between consumers′ perception of product benefits and actual benefits is something which should be further investigated in other products within the health food market.

Details

British Food Journal, vol. 92 no. 5
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 1 January 1990

Jeffrey N. Gatten

Massive bar coding projects require a great deal of planning and preparation, and usually involve most of a library's staff. The swift and efficient execution of the project is…

Abstract

Massive bar coding projects require a great deal of planning and preparation, and usually involve most of a library's staff. The swift and efficient execution of the project is paramount. While a large‐scale bar coding project can be intimidating, detailed planning can prevent hours of anxiety and the need for crisis management. This article attempts to provide a comprehensive overview of the relevant issues for a successful bar coding project. Selecting bar codes, planning and structuring a project, calculating time estimates, and maintaining staff morale are presented in detail. A selected bibliography provides access to more information.

Details

Library Hi Tech, vol. 8 no. 1
Type: Research Article
ISSN: 0737-8831

Article
Publication date: 24 May 2013

Ch. Alk. Apostolopoulos and Vassilios Kappatos

The corrosion of reinforcing steel bars reduces significantly the life and durability of concrete structures. This critical concern causes great losses to the economy and…

Abstract

Purpose

The corrosion of reinforcing steel bars reduces significantly the life and durability of concrete structures. This critical concern causes great losses to the economy and industry. The purpose of this paper is to estimate the effects of corrosion on the tensile mechanical properties of embedded steel bars B500c in concrete.

Design/methodology/approach

The concept is based on the curve fitting modelling, as well the mathematical correlation of the tensile mechanical properties between corroded bare and corroded embedded steel bars. In order to achieve this, extensive experiments were carried out on both bare (Ø8, 10, 12, 16 and 18 mm) and embedded (Ø8 mm) steel bars B500c, which were subjected to artificially accelerated corrosive conditions in a chloride‐rich atmosphere for several exposure times.

Findings

The research results show that the estimation method is available and effective in simulating the tensile mechanical behaviour of corroded reinforcing steel bars B500c.

Originality/value

As far as is known, this is the first time that an advanced data processing technique has been employed to try to find the mathematical correlation of the existing corrosion damage on the residual tensile properties between bare and embedded steel bars. It is argued that these models can be developed in order to reduce the need for expensive experimental investigation in materials.

Details

International Journal of Structural Integrity, vol. 4 no. 2
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 8 February 2024

Andreia C.B. Ferreira, Ricardo Gouveia Rodrigues, Ana R. Gouveia, Oliva M.D. Martins, Hugo Ferreira, João Alfredo Pereira and Paulo Duarte

The use of insects as food is a proposed solution for the increased demand for food worldwide, but it lacks acceptance because of restrictive emotional factors. This article aims…

Abstract

Purpose

The use of insects as food is a proposed solution for the increased demand for food worldwide, but it lacks acceptance because of restrictive emotional factors. This article aims to understand better customers' emotions’ role in considering and consuming insect-based food.

Design/methodology/approach

To assess their acceptance, an experiment was developed with 38 participants living in Portugal to identify how people feel when consuming processed insect bars compared to cereal bars (of equal flavour). A video was recorded “before”, “during” and “after” the consumption of such foods, and the triggered emotions and affective states were identified using the Facial Action Coding System (FACS) and the circumplex model of affect, respectively. After consumption, the Self-Assessment Manikin (SAM) was asked to be completed.

Findings

It was observed that the valence and arousal of the emotions and affective states triggered during consumption were higher in the insect bar than in the cereal bar. Its consumption resulted in surprise and a positive evaluation. Processed insect-based foods may result in a potentially increased acceptance of this new food alternative in the market.

Originality/value

Prior studies briefly identified disgust as a primary emotion activated by insect-based food. The current research deeply studied emotional responses to insect-based processed foods in the Western world using the dimensional emotional models. This study offers arguments for the insect-based food industry to invest in processed food justified by its potential for acceptance. In addition, it motivates further research focused on other insect-based products (e.g. non-processed ones).

Article
Publication date: 9 February 2024

Ayad Alameeri, Gholamreza Abdollahzadeh and Seyedkomeil Hashemiheidari

This study aims to determine the effect of replacing a portion of the cement in the concrete mixture with silica fume (SF) on the corrosion resistance of reinforcing bars, the…

Abstract

Purpose

This study aims to determine the effect of replacing a portion of the cement in the concrete mixture with silica fume (SF) on the corrosion resistance of reinforcing bars, the compressive strength of concrete and the tensile strength of hook bars in both corroded and non-corroded external joints of structures. The external beam-column connection was studied because of its critical role in maintaining structural continuity in all three directions and providing resistance to rotation.

Design/methodology/approach

In external concrete joints, the bars at the end of the beams are often bent at 90° to form hooks that embed in columns. Owing to the importance of embedding distance and the need to understand its susceptibility to corrosion damage from chloride attack, a series of experiments were conducted on 12 specimens that accurately simulate real-site conditions in terms of dimensions, reinforcement and hook bars. SF was replaced with 10% and 15% of the weight of cement in the concrete mixture. To simulate corrosion, the specimens were subjected to accelerated corrosion in the laboratory by applying a low continuous current of 0.35 mA for 58 days.

Findings

The results revealed the effect of SF in improving the compressive strength of concrete, the pullout resistance of the hook bars and the corrosion resistance. In addition, it showed an apparent effect of the corrosion of reinforcing bars in reducing the bonding strength of hook bars with concrete and the effect of SF in improving this strength.

Originality/value

It was noted that the improvement of the results, achieved by replacing 10% of the weight of cement with SF, was significantly close to the results obtained by replacing 15% of the SF. It is recommended that an SF ratio of 10% be adopted to achieve the greatest economic savings.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

Keywords

Book part
Publication date: 26 November 2021

Francisco J. Conejo, Enrique A. Gamboa and Andrea Insch

This study provides insights into the most salient elements of the Costa Rican bar servicescape/barscape (atmosphere). This is done qualitatively via six focus groups, six expert…

Abstract

This study provides insights into the most salient elements of the Costa Rican bar servicescape/barscape (atmosphere). This is done qualitatively via six focus groups, six expert interviews, and six on-site observations. Results indicate that servicescape elements traditionally covered by the literature are of secondary importance. Participants instead emphasized social elements (other patrons, staff), supplemented by ambience elements (music, lighting, colors, noise, air, odors, scents). Moreover, the underlying socialization interest steered ambience preferences. Results support the increasingly important social servicescape notion. Generalizing traditionally studied servicescape elements across cultures and hospitality settings, as conventionally done, may result suboptimal. Commonalities might exist. However, research should be specifically contextualized to gain more nuanced servicescape understandings. Relating servicescape preferences to macro, meso, and micro considerations further enhances how servicescapes are understood. This study is the first to explore Latin-American barscapes. Notably, it expressly links servicescape preferences to patronage motives. It thereby uncovers why certain servicescape elements become important.

Details

Advances in Hospitality and Leisure
Type: Book
ISBN: 978-1-80071-272-0

Keywords

Book part
Publication date: 21 December 2006

Jumpei Ichinosawa

Economic anthropology of bazaar-type markets for material goods has developed a model of markets under uncertain conditions through microscopic analyses of seller–buyer…

Abstract

Economic anthropology of bazaar-type markets for material goods has developed a model of markets under uncertain conditions through microscopic analyses of seller–buyer relationships. The model implies that serious lack of information makes the individuals highly risk-averse and leads to long-term, balanced clientelization. Presented in this chapter is another model of uncertain market conditions. In a bazaar-type market of interpersonal service the individuals are likely to be both chance-seekers as well as risk-averters. Such an attitude derives from a combination of unique service characteristics and uncertain market conditions. Transactions of commodified sexual services (termed here “interpersonally embedded services”) among chance-seekers in bangkok go-go bars often result in disequilibration, rather than equilibration, of the seller–buyer relationship.

Details

Choice in Economic Contexts
Type: Book
ISBN: 978-0-76231-375-4

Book part
Publication date: 17 February 2022

Theodore Greene

This chapter draws on 10 years of ethnographic fieldwork collected in gay bars from three American cities to explore the strategies LGBTQ subcultures deploy to recreate meaningful…

Abstract

This chapter draws on 10 years of ethnographic fieldwork collected in gay bars from three American cities to explore the strategies LGBTQ subcultures deploy to recreate meaningful places within the vestiges of local queer nightlife. As gentrification and social acceptance accelerate the closures of LGBTQ-specific bars and nightclubs worldwide, venues that once served a specific LGBTQ subculture (i.e., leather bars) expand their offerings to incorporate displaced LGBTQ subcultures. Attending to how LGBTQ subcultures might appropriate designated spaces within a gay venue to support community (nightlife complexes), how management and LGBT subcultures temporally circumscribe subcultural practices and traditions to create fleeting, but recurring places (episodic places), and how patrons might disrupt an existing production of place by imposing practices associated with a discrepant LGBTQ subculture(place ruptures), this chapter challenges the notion of “the gay bar” as a singular place catering to a specific subculture. Instead, gay bars increasingly constitute a collection of places within the same space, which may shift depending on its use by patrons occupying the space at any given moment. Beyond the investigation of gay bars, this chapter contributes to the growing sociological literature exploring the multifaceted, unstable, and ephemeral nature of place and place-making in the postmodern city.

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