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1 – 10 of over 7000
Article
Publication date: 11 June 2018

Patricia Raposo, André Furtado, António Arêde, Humberto Varum and Hugo Rodrigues

The infill masonry walls in recent worldwide earthquakes have shown that it is necessary to conduct further studies to characterize the behavior of existing buildings and, in…

Abstract

Purpose

The infill masonry walls in recent worldwide earthquakes have shown that it is necessary to conduct further studies to characterize the behavior of existing buildings and, in particular, of infill masonry walls under seismic activity. The lack of characterization studies of infill walls made by concrete blocks justifies the investigation reported herein, which includes experimental tests on sample sets to evaluate the mechanical properties of masonry components (units and mortar) and assemblages (wallets) made with masonry units from Faial. For the later, normal compressive, diagonal tensile/shear and out-of-plane flexural strengths were obtained according to standard procedures, the results of which are presented in the manuscript. The paper aims to discuss these issues.

Design/methodology/approach

One experimental campaign was conducted with the aim to mechanically characterize concrete blocks masonry samples. Several experimental tests were carried out in full-scale masonry concrete wallets according to the constructive methodology used.

Findings

Based on the data obtained from the mechanical characterization tests of the concrete masonry blocks, it can be seen that under simple compression, the masonry specimens’ average resistance is about 6 times superior than the average resistance to diagonal shear/tension, while the stiffness is almost doubled. In simple compression tests, it was observed that the masonry specimens cracked in areas of higher drilling of the blocks. In the tensile tests by diagonal compression, it was found that the test specimens were mainly fissured by the block/mortar joint interfaces, following the delineation of settlement and top joints.

Originality/value

There are no experimental results available in the literature for this type of bricks that can contribute to the development of numerical studies.

Details

International Journal of Structural Integrity, vol. 9 no. 3
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 14 June 2021

Juliana Villasante, Johanan Espinosa-Ramírez, Esther Pérez-Carrillo, Erick Heredia-Olea and MariaPilar Almajano

Solid-state fermentation (SSF) has been highlighted as an alternative to obtain valuable compounds using agro-industrial wastes as a substrate. The present study evaluated the…

Abstract

Purpose

Solid-state fermentation (SSF) has been highlighted as an alternative to obtain valuable compounds using agro-industrial wastes as a substrate. The present study evaluated the impact of extrusion combined with SSF on the production of phenolic compounds and their antioxidant activity using pecan nut shell (PWS) as a substrate.

Design/methodology/approach

PWS and extruded pecan nut shell (PWSE) were fermented for 120 h at 30°C using Aspergillus oryzae (A. oryzae). Samples were withdrawn from incubator at 6 h, 12 h and then every 12 h until 120 h fermentation. PWS and PWSE samples were extracted. The total phenolic content (TPC) and radical scavenging activity (RSA) extracts were characterized from the resulting extracts.

Findings

The use of PWSE yielded higher A. oryzae biomass and at a higher rate after 120 h of fermentation (PWS 75.74% vs PWSE 87.50%). In general, the TPC and the RSA increased with fermentation time. However, the PWSE yielded significantly higher (p < 0.05) TPC and RSA values after SSF in comparison to the nonextruded PWS. Condensed tannins showed different trends depending on the fermented substrate. Overall, results showed that the extrusion pretreatment joint with the SSF represents a good alternative to raise the phenolic content and antiradical activity of lignocellulosic materials such as PWSs.

Originality/value

This study offers valuable information that may be used by the pecan walnut industry to valorize the shell coproduct as a substrate to produce functional ingredients or fungal enzymes.

Details

British Food Journal, vol. 123 no. 12
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 13 June 2016

João Dias-Oliveira, H Rodrigues and Humberto Varum

When a numerous amount of buildings was built in reinforced concrete, in a period when the regulations did not have the design philosophy for the occurrence of earthquakes, it is…

Abstract

Purpose

When a numerous amount of buildings was built in reinforced concrete, in a period when the regulations did not have the design philosophy for the occurrence of earthquakes, it is of extreme importance to carry out full and effective structural assessments, specially considering and comparing bare frame and infilled structure. The paper aims to discuss these issues.

Design/methodology/approach

Among several possibilities to make the evaluation as, simplified, linear analysis and static non-linear analysis, the non-linear dynamic can provide the most accurate numerical behaviour compared to the real one. The time-history non-linear analyses are developed on the software SeismoStruct for different levels of intensity. Local verifications are then applied separately from both Eurocode and Italian Code.

Findings

The application of validated models for the analysis of real buildings allows a complete seismic assessment. The level of uncertainty increases integrating particularities regarding the infill masonry walls. The paper shows important global and local seismic safety for these complex typology of buildings.

Originality/value

A representative common concrete structure without seismic provisions is first analysed and discussed in terms of global behaviour, deformations and progression of forces. The case study structure is considered both as bare structure and with integrated infill panels. It is also discussed in a local level, about brittle and ductile mechanisms, and extra comparisons between different interpretations of different standards. The case study structure is considered both as bare structure and with integrated infill panels.

Details

Engineering Computations, vol. 33 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 18 December 2019

Muhammad Taimoor and Li Aijun

The purpose of this paper is to propose an adaptive neural-sliding mode-based observer for the estimation and reconstruction of unknown faults and disturbances for time-varying…

Abstract

Purpose

The purpose of this paper is to propose an adaptive neural-sliding mode-based observer for the estimation and reconstruction of unknown faults and disturbances for time-varying nonlinear systems such as aircraft, to ensure preciseness in the diagnosis of fault magnitude as well as the shape without enhancement of system complexity and cost. Fault-tolerant control (FTC) strategy based on adaptive neural-sliding mode is also proposed in the existence of faults for ensuring the stability of the faulty system.

Design/methodology/approach

In this paper, three strategies are presented: adaptive radial basis functions neural network (ARBFNN), conventional radial basis functions neural network (CRBFNN) and integral-chain differentiator. For the purpose of enhancement of fault diagnosis and isolation, a new sliding mode-based concept is introduced for the weight updating parameters of radial basis functions neural network (RBFNN).The main objective of updating the weight parameters adaptively is to enhance the effectiveness of fault diagnosis and isolation without increasing the computational complexities of the system. Results depict the effectiveness of the proposed ARBFNN approach in fault detection (FD) and approximation compared to CRBFNN, integral-chain differentiator and schemes existing in literature. In the second step, the FTC strategy is presented separately for each observer in the presence of unknown faults and failures for ensuring the stability of the system, which is validated on Boeing 747 100/200 aircraft.

Findings

The proposed adaptive neural-sliding mode approach is investigated, which depicts more effectiveness in numerous situations such as faults, disturbances and uncertainties compared to algorithms used in literature. In this paper, both the fault approximation and isolation and the fault tolerance approaches are studied.

Practical implications

For the enhancement of safety level as well as for avoiding any kind of damage, timely FD and fault tolerance have always had a significant role; therefore, the algorithms proposed in this research ensure the tolerance of faults and failures, which plays a vital role in practical life for avoiding any kind of damage.

Originality/value

In this study, a new neural-sliding mode concept is adopted for the adaptive faults approximation and reconstruction, and then the FTC algorithms are studied for each observer separately, whereas in previous studies, only the fault detection and isolation (FDI) or the fault tolerance problems were studied. Results demonstrate the effectiveness of the proposed strategy compared to the approaches given in the literature.

Details

Aircraft Engineering and Aerospace Technology, vol. 92 no. 2
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 23 September 2024

Nicolas Depetris Chauvin, Antoine Pinède and David Priilaid

This paper aims to examine the convergence and divergence of business and production practices in the global wine industry, particularly focusing on Pinot Noir producers in…

Abstract

Purpose

This paper aims to examine the convergence and divergence of business and production practices in the global wine industry, particularly focusing on Pinot Noir producers in Burgundy, New Zealand and South Africa (SA). This study explores the interplay between firm-specific factors and regional contexts to identify competitive advantage drivers among Pinot Noir producers.

Design/methodology/approach

This research uses a comparative analysis approach, using data from a comprehensive winery level survey. This study applies methodologies akin to value chain analysis to unravel the configuration of productive and technology/knowledge creation activities within wineries across three regions.

Findings

This analysis reveals both convergence and divergence in business and production practices among Pinot Noir producers in Burgundy, New Zealand and South Africa. Although there is a degree of convergence in marketing, distribution and competition strategies, differences exist in production practices and firms’ capabilities. Burgundy emphasizes tradition and terroir expression, contrasting with the modernization and innovation focus observed in New Zealand and South Africa. However, all regions share a commitment to quality as a competitive advantage.

Research limitations/implications

This study acknowledges limitations such as the focus on a specific grape variety and regions, the absence of performance impact analysis and the need for additional variables like environmental, institutional and cultural factors and consumer preferences to provide a comprehensive understanding of industry dynamics.

Practical implications

The insights from this study offer practical implications for winemakers, industry stakeholders and policymakers. Producers can optimize production and marketing strategies based on regional contexts and market segments, whereas stakeholders can identify emerging trends and opportunities in the global wine market. Policymakers can develop targeted policies supporting innovation, sustainability and competitiveness.

Originality/value

This paper provides a unique contribution by conducting a comparative firm-level analysis across distinct wine-producing regions, shedding light on the nuanced interplay of factors shaping competitive advantage among Pinot Noir producers. This study’s comprehensive data set and methodological approach enhance understanding and offer valuable insights for industry stakeholders and policymakers.

Details

International Journal of Wine Business Research, vol. 36 no. 4
Type: Research Article
ISSN: 1751-1062

Keywords

Article
Publication date: 21 September 2021

Hemanth Kumar Chinthapalli and Anil Agarwal

Earthquake tremors not only increase the chances of fire ignition but also hinder the fire-fighting efforts due to the damage to the lifelines of a city. Most of the international…

Abstract

Purpose

Earthquake tremors not only increase the chances of fire ignition but also hinder the fire-fighting efforts due to the damage to the lifelines of a city. Most of the international codes have independent recommendations for structural safety against earthquake and fire. However, the possibility of a multi-hazard event, such as fire following an earthquake is seldom addressed.

Design/methodology/approach

This paper presents an experimental study of Reinforced Concrete (RC) columns in post-earthquake fire (PEF) conditions. An experimental approach is proposed that allows the testing of a column instead of a full structural frame. This approach allows us to control the loading and boundary conditions individually and facilitates the testing under a variety of these conditions. Also, it allows the structure to be tested until failure. The role of parameters, such as earthquake intensity, axial load ratio and the ductile detailing of the column on the earthquake damage and subsequently the fire performance of the structure, is studied in this research. Six RC column specimens are tested under a sequence of quasi-static earthquake loading, followed by combined fire and axial compression loading conditions.

Findings

The experiment results indicate that ductile detailed columns subjected to 4% or less lateral drift did not lose significant load-carrying capacity in fire conditions. A lateral drift of 6% caused significant damage to the columns and reduced the load-carrying capacity in fire conditions. The level of the axial load acting on the column at the time of earthquake loading was found to have a very significant effect on the extent of damage and reduction in column load capacity in fire conditions. The columns that were not detailed for a ductile behavior observed a more significant reduction in axial load carrying capacity in fire conditions.

Research limitations/implications

This study is limited to columns of 230 mm size due to the limitations of the test setup. The applicability of these findings to larger column sections needs to be verified by developing a numerical analysis methodology and simulating other post-earthquake-fire tests available in the literature.

Originality/value

The experimental procedure proposed in this paper offers an alternative to the testing of a complete structural frame system for PEF behavior. In addition to the ease of conducting the tests, the procedure also allows much better control over the heating, structural loading and boundary conditions.

Details

Journal of Structural Fire Engineering, vol. 13 no. 1
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 29 March 2023

Jianbo Yuan, Yerui Fan and Yaxiong Wu

This study aims to propose a novel lightweight tendon-driven musculoskeletal arm (LTDM-arm) robot with a flexible series–parallel mixed skeletal joint structure and modularized…

Abstract

Purpose

This study aims to propose a novel lightweight tendon-driven musculoskeletal arm (LTDM-arm) robot with a flexible series–parallel mixed skeletal joint structure and modularized artificial muscle system (MAMS). The proposed LTDM-arm exhibits human-like flexibility, safety and operational accuracy. In addition, to improve the safety and stability of the LTDM-arm, a control method is proposed to solve local artificial muscle overload accidents.

Design/methodology/approach

The proposed LTDM-arm comprises seven degrees of freedom skeletons, 15 MAMSs and various sensor systems (joint sensing, muscle tension sensing, visual sensing, etc.). It retains the morphology of a human skeleton (humerus, ulna and radius) and a simplified muscle configuration. This study proposes an input saturation control with full-state constraints to reduce local artificial muscle overload accidents caused by redundant muscle tension calculations.

Findings

3D circular trajectory experiments were conducted to verify the stability of the control method and the flexibility of the LTDM-arm. The results showed that the average error of the muscle length was approximately 0.35 mm (0.38%), which indicates that the proposed control scheme can make the output follow the target trajectory while ensuring constraint satisfaction.

Originality/value

The human arm is capable of performing compliant operations rapidly, flexibly and robustly in unstructured environments. Existing musculoskeletal arm robots lack simulations of the full morphology of the human arm and are insufficient in dexterity. However, the flexibility and safety features of the proposed LTDM-arm were consistent with that of the human arm. Therefore, this study offers a new approach for investigating the advantages of the musculoskeletal system and the concepts of muscle control.

Details

Robotic Intelligence and Automation, vol. 43 no. 2
Type: Research Article
ISSN: 2754-6969

Keywords

Open Access
Article
Publication date: 1 October 2024

Giuditta Farina, Mirta Casati and Paolo Sckokai

The main objective of this study is to analyze consumers’ willingness to pay (WTP) for country-of-origin (COO) labels of two processed food products, disentangling the value of…

Abstract

Purpose

The main objective of this study is to analyze consumers’ willingness to pay (WTP) for country-of-origin (COO) labels of two processed food products, disentangling the value of information (VOI) that consumers place on COO information from the value they place on specific countries of origin.

Design/methodology/approach

A convenience sample of 96 university students completed a face-to-face experiment that included a multiple price list and a discrete choice experiment. Data are analyzed employing interval censored regressions, and random parameter logit models.

Findings

Our results indicate that, on average, consumers place a higher value on origin information when a country name is explicitly mentioned. Furthermore, COO information is, on average, more relevant to consumers for products with low involvement than for products with high involvement. Finally, the effect of ethnocentrism is heterogeneous across product categories.

Research limitations/implications

Mandatory COO labeling may or may not reinforce domestic bias, depending on the rationale behind consumer support. If consumers are driven by blind ethnocentrism, it may lead to market inefficiencies. However, if they use COO as a cue to align their stated preferences with their choices, it will not. For this alignment to occur, consumers must be fully informed about product attributes, which requires new and smart methods of communicating product attributes.

Originality/value

The present study contributes to the literature on COO food labels, being the first in Italy to disentangle the VOI consumers place on origin information itself from the value they place on specific countries of origin. In addition, it is the first study that applies this methodology across different product categories, each of which has a different level of cultural sensitivity to consumers.

Details

British Food Journal, vol. 126 no. 13
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 9 April 2021

Mona Zaryoun, Mahmood Hosseini and Kaveh Soleymani

The main purpose of this study is revival of vernacular architecture of Zegalli houses, which can be beneficial in several aspects of sustainable architecture, and therefore, its…

Abstract

Purpose

The main purpose of this study is revival of vernacular architecture of Zegalli houses, which can be beneficial in several aspects of sustainable architecture, and therefore, its reuse in contemporary architecture can be strongly recommended. Zegalli houses, in northern Iran, are almost-entirely wooden vernacular houses, which beside to having several aspects of sustainable architecture, have shown good resistance against past earthquakes. Their relatively good seismic performance is mainly because of their specific timber foundation, which creates a kind of rocking/rolling isolation, as well as their light weight and diagonally braced stiff walls.

Design/methodology/approach

In this paper, first the architectural features of Zegalli houses, particularly energy efficiency, sustainability and eco-friendliness are described. Then, their structural system, focusing more on their foundation, is discussed. Finally, a simplified model of the house, developed in a powerful finite element analysis program, is introduced, and sample results of a series of time history analyses (THA), employing three-component accelerograms of three selected earthquakes, are presented.

Findings

Results of THA show that the rocking/rolling behavior of foundation timbers in various levels significantly reduces seismic response of the house, leading to its stability against earthquakes with peak ground acceleration up to 0.25 g.

Practical implications

Regarding the architectural and structural merits of Zegalli houses, they can be considered as sustainable vernacular architecture, and therefore, architects and civil and structural engineers are encouraged to reconsider the use of these houses, with some modifications, in future developments.

Originality/value

3D dynamics analysis of Shikilli foundations of Zegalli houses is done for the first time in this study.

Details

Engineering, Construction and Architectural Management, vol. 29 no. 2
Type: Research Article
ISSN: 0969-9988

Keywords

Book part
Publication date: 23 August 2021

Mohammad Nurunnabi

The study aims at reviewing a synthesis of disclosure, transparency, and International Financial Reporting Standards (IFRS) implementation in an attempt to provide directions for…

Abstract

The study aims at reviewing a synthesis of disclosure, transparency, and International Financial Reporting Standards (IFRS) implementation in an attempt to provide directions for future research. Prior research overwhelmingly supports that the IFRS adoption or effective implementation of IFRS will enhance high-quality financial reporting, transparency, enhance the country’s investment environment, and foreign direct investment (FDI) (Dayanandan, Donker, Ivanof, & Karahan, 2016; Gláserová, 2013; Muniandy & Ali, 2012). However, some researchers provide conflicting evidence that developing countries implementing IFRS are probably not going to encounter higher FDI inflows (Gheorghe, 2009; Lasmin, 2012). It has also been argued that the IFRS adoption decreases the management earnings in countries with high levels of financial disclosure. In general, the study indicates that the adoption of IFRS has improved the financial reporting quality. The common law countries have strong rules to protect investors, strict legal enforcement, and high levels of transparency of financial information. From the extensive structured review of literature using the Scopus database tool, the study reviewed 105 articles, and in particular, the topic-related 94 articles were analysed. All 94 articles were retrieved from a range of 59 journals. Most of the articles (77 of 94) were published 2010–2018. The top five journals based on the citations are Journal of Accounting Research (187 citations), Abacus (125 citations), European Accounting Review (107 citations), Journal of Accounting and Economics (78 citations), and Accounting and Business Research (66 citations). The most-cited authors are Daske, Hail, Leuz, and Verdi (2013); Daske and Gebhardt (2006); and Brüggemann, Hitz, and Sellhorn (2013). Surprisingly, 65 of 94 articles did not utilise the theory. In particular, four theories have been used frequently: agency theory (15), economic theory (5), signalling theory (2), and accounting theory (2). The study calls for future research on the theoretical implications and policy-related research on disclosure and transparency which may inform the local and international standard setters.

Details

International Financial Reporting Standards Implementation: A Global Experience
Type: Book
ISBN: 978-1-80117-440-4

Keywords

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