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Top-seat angle connection is known as one of the usual uncomplicated beam-to-column joints used in steel structures. This article investigates the fire performance of welded top-seat angle connections.

A finite element (FE) model, including nonlinear contact interactions, high-temperature properties of steel, and material and geometric nonlinearities was created for accomplishing the fire performance analysis. The FE model was verified by comparing its simulation results with test data. Using the verified model, 24 steel-framed top-seat angle connection assemblies are modeled. Parametric studies were performed employing the verified FE model to study the influence of critical factors on the performance of steel beams and their welded angle joints.

The results obtained from the parametric studies illustrate that decreasing the gap size and the top angle size and increasing the top angles thickness affect fire behavior of top-seat angle joints and decrease the beam deflection by about 16% at temperatures beyond 570 °C. Also, the fire-resistance rating of the beam with seat angle stiffener increases about 15%, compared to those with and without the web stiffener. The failure of the beam happens when the deflections become more than span/30 at temperatures beyond 576 °C. Results also show that load type, load ratio and axial stiffness levels significantly control the fire performance of the beam with top-seat angle connections in semi-rigid steel frames.

Development of design methodologies for these joints and connected beam in fire conditions is delayed by current building codes due to the lack of adequate understanding of fire behavior of steel beams with welded top-seat angle connections.

The purpose of this study is to solve NP-Hard drone routing problem for the last-mile distribution. This is suitable for the multi-drones parcel delivery for the various items from a warehouse to many locations.

This study conducts as a mission assignment of the single location per flight with the constraint satisfactions such as various payloads in weight, drone speeds, flight times and coverage distances. A genetic algorithm is modified as the concurrent heuristics approach (GCH), which has the knapsack problem dealing initialization, gene elitism (crossover) and gene replacement (mutation). Those proposed operators can reduce the execution time consuming and enhance the routing assignment of multiple drones. The evaluation value of the routing assignment can be calculated from the chromosome/individual representation by applying the proposed concurrent fitness.

This study optimizes the total traveling time to accomplish the distribution. GCH is flexible and can provide a result according to the first-come-first-served, demanded weight or distance priority.

GCH is an alternative option, which differs from conventional vehicle routing researches. Such researches (traveling time optimization) attempt to minimize the total traveling time, distance or the number of vehicles by assuming all vehicles have the same traveling speed; therefore, a specific vehicle assignment to a location is neglected. Moreover, the main drawback is those concepts can lead the repeated selection of best quality vehicles concerning the speed without considering the vehicle fleet size and coverage distance while this study defines the various speeds for the vehicles. Unlike those, the concurrent concept ensures a faster delivery accomplishment by sharing the work load with all participant vehicles concerning to their different capabilities. If the concurrent assignment is applied to the drone delivery effectively, the entire delivery can be accomplished relatively faster than the traveling time optimization.

In recent years, fire accidents in engineering structures have often been reported worldwide, leading to a severe risk to life and property safety. The present study is carried out to evaluate the performance of Ground Granulated Blast Furnace Slag (GGBS) and fly ash–blended laterized mortars at elevated temperatures.

This test program includes the replacement of natural river sand with lateritic fine aggregates (lateritic FA) in terms of 0, 50 and 100%. Also, the ordinary Portland cement (OPC) was replaced with fly ash and GGBS in terms of 10, 20, 30% and 20, 40 and 60%, respectively, for producing blended mortars.

This paper presents results related to the determination of residual compressive strengths of lateritic fine aggregates-based cement mortars with part replacement of cement by fly ash and GGBS exposed to elevated temperatures. The effect of elevated temperatures on the physical and mechanical properties was evaluated with the help of microstructure studies and the quantification of hydration products.

A sustainable cement mortar was produced by replacing natural river sand with lateritic fine aggregates. The thermal strength deterioration features were assessed by exposing the control specimens and lateritic fine aggregates-based cement mortars to elevated temperatures. Changes in the mechanical properties were evaluated through a quantitative microstructure study using scanning electron microscopy (SEM) images. The phase change of hydration products after exposure to elevated temperatures was qualitatively analyzed by greyscale thresholding of SEM images using Image J software.

The purpose of this paper is to explore the microfoundations of innovation-enabling dynamic capabilities in Latin American firms and, in particular, their processes to: sense and shape opportunities; seize opportunities; and maintain competitiveness through reconfiguring assets.

The authors carried out a confirmatory factor analysis of survey data obtained from a sample of 721 firms located in Latin America, and employed a hierarchical analysis of linear regressions with robust standard errors to test the hypotheses.

The authors found that when firms manage their innovation processes based on sensing opportunities and reconfiguring their tangible and intangible assets, they are more likely to improve on four innovation-related outcomes: development of new products and services; profitability; market share; and diversification.

The findings are limited to the specific context of Latin American countries. In particular, the authors took a random sample of firms from a business directory built by prestigious Latin American business schools, but that may not be representative. Therefore, the generalizability of the results is limited beyond the type of companies that are represented in that sampling frame.

Contributions are twofold. First, the authors test the applicability of an orchestration model of dynamic capabilities to the Latin American context. And, second, the authors relate specific microfoundations of dynamic capabilities to the ability of firms to innovate successfully.

El objetivo de este documento es explorar las micro-fundaciones de las capacidades dinámicas que hacen posible la innovación en las empresas latinoamericanas. En particular, sus procesos para: (1) detectar y dar forma a las oportunidades, (2) aprovechar las oportunidades y (3) mantenerse competitivas a través de la reconfiguración de sus activos.

Realizamos un análisis factorial confirmatorio con datos de una encuesta que hicimos a una muestra de 721 empresas en Latinoamérica, y empleamos un análisis jerárquico de regresiones lineales con error estándar robusto para probar nuestras hipótesis.

Encontramos que cuando las empresas administran sus procesos de innovación basándose en (1) la detección de oportunidades y (2) la reconfiguración de sus activos tangibles e intangibles, es más probable que mejoren en cuatro objetivos relacionados a innovación: (1) desarrollo de nuevos productos y servicios, (2) sus retornos, (3) participación de mercado y (4) diversificación.

Nuestros hallazgos están limitados al contexto específico de los países de América Latina. Específicamente, tomamos una muestra aleatoria de empresas de un directorio de negocios creado por prestigiosas escuelas de negocios latinoamericanas, pero que puede no ser representativo. Entonces, la generalizabilidad de nuestros resultados es limitada más allá del tipo de empresas que están representadas en este marco muestral.

Las contribuciones son dobles. Primero, probamos la aplicabilidad de un modelo de orquestación de capacidades dinámicas en el contexto latinoamericano. Y, segundo, relacionamos micro-fundaciones específicas de capacidades dinámicas con la habilidad de las empresas para innovar exitosamente.

This study aims to investigate the production and abrasive wear rate of functionally graded TiB₂/Al composites. TiB₂ particles have been spontaneously formed in liquid matrix using in situ technique. The properties of composites such as hardness, abrasive wear rate and microstructure have been examined.

In situ TiB₂ reinforcement phase was synthesized by using a liquid Al–Ti–B system. A semi-solid composite (Al_(l)-TiB_2(s)) prepared at 900°C was solidified under a centrifugal force to both grade functionally and give the final shape to materials. Abrasive wear test of materials was conducted using the pin-on-disk method at room temperature. The wear tests were carried out with two different loads of 1 Newton (N) and 2 N, a sliding velocity of 3.5 m s⁻¹ and a sliding distance of 75 m.

This research provided the following findings; TiB₂ particles can be successfully synthesized with in situ reaction technique in molten aluminum. It was determined that abrasive wear rate increases with increasing load and decreases with increasing TiB₂ reinforcement content within matrix.

In previous studies, there have been many trials on the in situ production of TiB₂-reinforced aluminum matrix composites. However, there are few studies on production of in situ TiB₂-reinforced aluminum matrix functionally graded materials. At the same time, there is no study that the properties of composite, such as hardness and abrasive wear rate, are examined together according to centrifugal force.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2019-0538/

Sixty‐year‐old engineer and businessman, former minister of state and air force officer Ozires Silva has been inaugurated as Embraer's new chief executive officer in a ceremony presided over by the Minister for Air, brigadier Sócrates da Costa Monteiro, and attended by approximately 500 authorities and invited guests. Ozires replaces former CEO João Rodrigues da Cunha Neto, who resigned last June 26th.

The purpose of this paper is to identify the views of Swedish pig producers concerning animal welfare, the schemes practised for animal welfare in Sweden, and the ramifications of animal welfare for Swedish retailers and consumers.

The Swedish study for animal welfare covers a pig‐production sector of 2,794 producers (2005). The pig production study was one of three such studies conducted as part of the EU's Welfare Quality project with semi‐structured interviews (the other two studies were on cattle and poultry production). The stratified sample included 60 pig producers, both conventional and organic, selected from all areas of Sweden.

The main results show a high level of animal care exercised in the Swedish pig production sector. Although there are no specific animal welfare schemes implemented, there is a high level of animal care provided by farmer participation in quality assurance schemes that include animal welfare stipulations, among other criteria.

The results from this pig production study will serve as input for a subsequent study of the on‐farm practice of animal welfare for the Welfare Quality project and as information material for policy to argue for more compatible criteria of welfare schemes at national level as well as for more homogeneous practice and standards of animal welfare within the EU.

This is the first in‐depth study on animal welfare in Swedish agriculture that takes into account a wide array of views and experiences of both conventional and organic producers. Prior to this animal welfare study only studies with a narrow focus on animal welfare, for example about organic production, and the State Audit Institution's report, which focuses on the effectiveness in animal welfare monitoring, have been produced.

A large amount of legislation in the field of EC banking and financial services has been produced in preparation for the 1993 deadline for a single market. In some areas the legislative programme has been more successful than in others. This paper examines one field, that of regulation of undertakings for collective investment in transferable securities — more commonly known in this country as unit trusts — and shows how far the aims of the single market legislators have been, and can realistically be, achieved in this context.

THERE are few places where standards play such an essential role as in the aircraft industry, for an aircraft such as the Vickers VC10 long‐range airliner is made up of many thousands of large and small components, and since the development of a new aircraft already takes many years, it can be appreciated that without standardization of many of the basic parts, the task would be well‐nigh impossible.