Redouane Zellagui, Ahmed Bellaouar and Lachi Mohammed
The present paper aims to present a numerical modeling of a train bogie following a railway accident in the Algerian railway which clearly showed the presence of cracks at the…
Abstract
Purpose
The present paper aims to present a numerical modeling of a train bogie following a railway accident in the Algerian railway which clearly showed the presence of cracks at the level of the bogie axles.
Design/methodology/approach
Our approach consists of making a numerical modeling in dynamic under variable load taking into account the reality of several parameters.
Findings
The aim is to present a predictive model allowing the identification of the probable causes that are the cause of this premature deterioration. We have determined the lifetime and the influence of frequency on railway axle. Also, the influence of overload on railway axle. The numerical model will be directed by Ansys software.
Originality/value
Our study allowed us to understand the mechanical behavior of a railway axle under several loadings, and to determine the critical value of the final failure to avoid damage.
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This chapter assesses public administration in Paraguay. It argues that the country's public administration and public personnel structures have been shaped by a predominance of…
Abstract
This chapter assesses public administration in Paraguay. It argues that the country's public administration and public personnel structures have been shaped by a predominance of informal decision-making norms, patron–client relations, exceptional legislative interference in what elsewhere tend to be executive prerogatives, and weak accountability mechanisms of a state largely captured by a small oligarchy. In this context, administrative reform has been mostly instigated by external actors—donors and international financial institutions—and only achieved incremental progress in, in particular, the modernization of public finance institutions during periods of economic crises or political change when external demand coincided with domestic pressure. Except for some “pockets of efficiency,” Paraguay thus remains a benchmark case of a neopatrimonial state in a formally democratic Presidential system, in which informal patron–client relations trump formal bureaucratic structures—albeit one in which the legislature has exceptional influence over administrative matters and public sector jobs are exceptionally dominant in clientelist exchanges of state resources.
S. Beleulmi, A. Bellaouar and M. Lachi
The lack of reliability testing in a project finds its reason in financial considerations and deadlines. In this context, Bayesian techniques find their applications as they…
Abstract
The lack of reliability testing in a project finds its reason in financial considerations and deadlines. In this context, Bayesian techniques find their applications as they contribute to a significant reduction in the amount of reliability testing based on the classical approach, with the knowledge of the reliability data on a priori relevant components. This paper is devoted to a Bayesian approach to the optimization reliability costs of tests conducted on the electronic components installed in a lift. The Bayesian estimation provides a failure rate of 1,795·10-6 failure/hr to 60% confidence instead of 2,771·10-6 failure / hr after testing. A gain of 64, 77% in terms of time and therefore the cost of testing will be reduced considerably. When the number of failures increases (K0 = 2; 3 and 5), the real tests are not added to virtual testing and a decrease in time to be won has been recorded.
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Ali Mostafaeipour, Hossein Goudarzi, Ahmad Sedaghat, Mehdi Jahangiri, Hengameh Hadian, Mostafa Rezaei, Amir-Mohammad Golmohammadi and Parniyan Karimi
In hot and dry climates, air conditioning accounts for a large portion of total energy consumption; therefore, this paper aims to investigate the impact of sol-air temperature and…
Abstract
Purpose
In hot and dry climates, air conditioning accounts for a large portion of total energy consumption; therefore, this paper aims to investigate the impact of sol-air temperature and ground temperature on the loss of cooling energy in hot and dry regions of Iran.
Design/methodology/approach
In line with this objective, the values of sol-air temperature along different directions and ground temperature at different depths were assessed with respect to climatic data of Yazd City. The impact of sol-air temperature and ground temperature on the rate of heat loss was investigated. So, energy loss of the walls aligned to four primary directions was calculated. This process was repeated for a 36 m2 building with three different shape factors. All analyses were conducted for the period from May to September, during which buildings need to be cooled by air conditioners.
Findings
Numerical analyses conducted for hot and dry climate show that sol-air temperature leads to a 41-17 per cent increase in the wall’s energy loss compared with ambient temperature. Meanwhile, building the wall below the surface leads to a significant reduction in energy loss. For example, building the wall 400 cm below the surface leads to about 74.8-79.2 per cent energy saving compared with above ground design. The results also show that increasing the direct contact between soil and building envelope decreases the energy loss, so energy loss of a building that is built 400 cm below the surface is 53.7-55.3 per cent lower than that of a building built above the surface.
Originality/value
The impact of sol-air temperature and ground temperature on the cooling energy loss of a building in hot and dry climate was investigated. Numerical analysis shows that solar radiation increases heat loss from building envelope. Soil temperature fluctuations decrease with depth. Heat loss from building envelope in an underground building is lower than that from building envelope in a building built above the ground. Three different shape factors showed that sol-air temperature has the maximum impact on square-shaped plan and minimal impact on buildings with east-west orientation.
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Aissa Boucedra and Madani Bederina
This paper aims to characterize and develop a new ecological lightweight concrete reinforced by addition of palm plant fibers (from vegetal waste) to be used in the thermal and…
Abstract
Purpose
This paper aims to characterize and develop a new ecological lightweight concrete reinforced by addition of palm plant fibers (from vegetal waste) to be used in the thermal and acoustical insulation of local constructions. The date palm plant fibers are characterized by their low sensitivity to chemical reactions, low cost and large availability in local regions. Therefore, the newly obtained lightweight concrete may suggest a great interest, as it seems to be able to achieve good solutions for local construction problems, technically, economically and ecologically.
Design/methodology/approach
The experimental program focused on developing the composition of palm-fiber-reinforced concrete, by studying the effect of the length of the fibers (10, 20, 30 and 40 mm) and their mass percentage (0.5%, 1%, 1.5% and 2%), on the mechanical and acoustical properties of the composite. The main measured parameters were the compressive strength and flexural strength, sound absorption coefficient, noise reduction coefficient (NRC), etc. These tests were also borne out by the measure of density and water absorption, as well as microstructure analyses. To fully appreciate the behavior of the material, visualizations under optical microscope and scanning electron microscope analyses were carried out.
Findings
The addition of plant fibers to concrete made it possible to formulate a new lightweight concrete having interesting properties. The addition of date palm fibers significantly decreased the density of the concrete and consequently reduced its mechanical strength, particularly in compression. Acceptable compressive strength values were possible, according to the fibers content, while better values have been obtained in flexion. On the other hand, good acoustical performances were obtained: a considerable increase in the sound absorption coefficient and the NRC was recorded, according to the content and length of fibers. Even the rheological behavior has been improved with the addition of fibers, but with short fibers only.
Originality/value
Over the recent decades, many studies have attempted to search for more sustainable and environmentally friendly building materials. Therefore, this work aims to study the possibility of using waste from date palm trees as fibers in concrete instead of the conventionally used fibers. Although many researches have already been conducted on the effect of palm plant fibers on the mechanical/physical properties of concrete, no information is available neither on the formulation of this type of concrete nor on its acoustical properties. Indeed, due to the scarcity of raw materials and the excessive consumption of energy, the trend of plant fibers as resources, which are natural and renewable, is very attractive. It is therefore a major recycling project of waste and recovery of local materials.
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Roseane L. Silva, João N.N. Quaresma, Carlos A.C. Santos and Renato M. Cotta
The purpose of this paper is to provide an analysis of two‐dimensional laminar flow in the entrance region of wavy wall ducts as obtained from the solution of the steady…
Abstract
Purpose
The purpose of this paper is to provide an analysis of two‐dimensional laminar flow in the entrance region of wavy wall ducts as obtained from the solution of the steady Navier‐Stokes equations for incompressible flow.
Design/methodology/approach
The study is undertaken by application of the generalized integral transform technique in the solution of the steady Navier‐Stokes equations for incompressible flow. The streamfunction‐only formulation is adopted, and a general filtering solution that adapts to the irregular contour is proposed to enhance the convergence behavior of the eigenfunction expansion.
Findings
A few representative cases are considered more closely in order to report some numerical results illustrating the eigenfunction expansions convergence behavior. The product friction factor‐Reynolds number is also computed and compared against results from discrete methods available in the literature for different Reynolds numbers and amplitudes of the wavy channel.
Research limitations/implications
The proposed methodology is fairly general in the analysis of different channel profiles, though the reported results are limited to the wavy channel configuration. Future work should also extend the analysis to geometries represented in the cylindrical coordinates with longitudinally variable radius.
Practical implications
The error‐controlled converged results provide reliable benchmark results for the validation of numerical results from computational codes that address the solution of the Navier‐Stokes equations in irregular geometries.
Originality/value
Although the hybrid methodology is already known in the literature, the results here presented are original and further challenges application of the integral transform method in the solution of the Navier‐Stokes equations.
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Nawal Chemma, Mohammed El Amine Abdelli, Anjali Awasthi and Emmanuel Mogaji
Management of information technology (IT) will continue to be an essential endeavour for organisations as we experience the increasing advancement of technology across different…
Abstract
Management of information technology (IT) will continue to be an essential endeavour for organisations as we experience the increasing advancement of technology across different spectres of life. Managers will need to understand how technology is changing their business operations and the emergence of digital consumers who demand more innovative and technologically driven experiences. This book was conceptualised to provide theoretical insight for managers and researchers to understand where we are and where technology is taking us. This book has presented different chapters, highlighting management and practical implications across other technology, sector and countries. These selected chapters provide a wide variety of stimulating insights into the varying challenges and perspectives of management and IT in the digital era. Significantly, we recognise the growing prospects of Artificial intelligence (AI) and how it is revolutionising different sectors, further presenting critical challenges for managers on how to harness the opportunities of this technology for their business prospects.
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Bechir Sabiha and Lachi Oualid
This study aims to study the reality and prospects of the digital economy in Algeria through annual reports and statistics that present the usefulness of digitalisation in…
Abstract
This study aims to study the reality and prospects of the digital economy in Algeria through annual reports and statistics that present the usefulness of digitalisation in Algerian economic sectors. Using an analytical study, we conclude that the economic sector had not experienced remarkable development in terms of digitalisation, except for a few activities in a few sectors such as health, industry and services that have experienced a gradual evolution to new information and communication technologies, which have brought added value in Algeria.
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Cosmas Gatot Haryono and Cindy Wijaya
The goal of this study is to learn about of the strategic framework used by event organizers in Indonesia to survive the COVID-19 pandemic. This effort is also used to see how…
Abstract
Purpose
The goal of this study is to learn about of the strategic framework used by event organizers in Indonesia to survive the COVID-19 pandemic. This effort is also used to see how crisis management is implemented in the organization, particularly in relation to the company's efforts to maximize technology in this COVID-19 crisis situation.
Design/methodology/approach
This is a qualitative study that employs the case study method with a single intrinsic case. Researchers chose six sources based on the range of responsibilities and authorities they have.
Findings
To remain viable faced with COVID-19 pandemic, event organizers must adopt an open communication strategy, be ready to adapt to changing conditions and take bold steps in crisis management. In general, Garuda Organizer's crisis management strategy consists of five stages: crisis research, forming a crisis team, planning crisis management steps, implementing a new work system and adapting to the new system's culture.
Research limitations/implications
The focus of this research is on how to deal with crisis strategies in the world of event organizer from the standpoint of innovation diffusion. This study cannot be generalized because it is limited to efforts to formulate a strategic framework carried out by event organizer companies in dealing with the COVID-19 pandemic, not seeing the effectiveness of the strategy.
Practical implications
This research, in addition to its theoretical implications, provides practical contributions to the event organizer industry. The pandemic encourages every event organizer company to always be prepared to adapt to changing conditions. There is no such thing as a static condition; rather, it can change abruptly at any time. As a result, the most important requirement is a quick and precise response. Responsive leadership will ensure that the adaptation process goes smoothly. With uncertain conditions, businesses must be prepared to respond to any changes that occur at any time. Sometimes desperate action is required because it must be done quickly. Aside from that, do not overlook openness management. It will be easier to manage a crisis if all available communication channels are opened. Opening all communication channels allows all components of the company to participate in overcoming the crisis. The participation of all parties will make it easier to deal with any crisis that arises. This transparency is carried out not only within the company, but also with parties outside the company, such as the government as a regulator, company partners and community members who use our services. Aside from that, a willingness to change and step outside of one's comfort zone is required both within the company and for each individual employee. The company's willingness to try new things and learn quickly becomes critical for businesses in the midst of a crisis. As in the case of Garuda Organizer, a willingness to constantly learn and develop a new culture that is more in line with current conditions will make the company more adaptable in dealing with crises. Thus, effective crisis-response strategies can be developed quickly. When we are at ease in certain circumstances, as employees, we are often hesitant to change, even if the times or circumstances have changed dramatically. It is necessary to avoid the comfort of the status quo. It takes self-will to change in a crisis like this. What does not change will be forgotten by time. To maintain the continuity of the company's activities, all employees must be willing to give up their comfort and possibly make a small sacrifice (including time and effort). If companies can unite the interests of companies and individuals who work as employees (As the management and employees of Garuda Organizer have done by devoting more time to the company's future and delving deeper into one's own potential), they will undoubtedly survive the current crisis.
Social implications
This study discovered that even in the midst of the COVID-19 pandemic, which is fraught with restrictions, there still are event organizer companies striving to provide the best service. The Garuda Organizer company strives to provide good service to its customers by disseminating innovations. Despite the limited circumstances, the public continues to enjoy events in a novel format, namely through virtual spaces.
Originality/value
This study identifies the use of technology as a means to overcome the problem of organizing events in the midst of the COVID-19 pandemic and maps the complexity of the innovation adoption process in Indonesian event organizer firms.