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Article
Publication date: 4 March 2016

Gang Yang, Rangqi Liu, De'an Hu and Xu Han

This paper aims to study the ability of SPH method in simulating shock initiation process. The initiation and subsequent explosion processes of condensed explosive involve high…

214

Abstract

Purpose

This paper aims to study the ability of SPH method in simulating shock initiation process. The initiation and subsequent explosion processes of condensed explosive involve high pressure propagation and material large deformation, which increase the simulation difficulty in using traditional mesh-based method. The study aims to take the SPH method as an alternative method to shock initiation simulation.

Design/methodology/approach

The SPH method combined with some correct aspects is applied to simulate the shock initiation process. The condensed explosive is ignited by the impact of high speed flyer. In order to avoid the non-physical penetration between particles of high velocity flyer and condensed explosive, a particle-to-particle contact algorithm is employed. After the ignition, the detonation process of condensed explosive is represented by the ignition and growth model. A modified SPH method based on Riemann-solver is applied to smooth the numerical oscillation at shock front. Two numerical examples are implemented to illustrate the capability of SPH method in shock initiation simulation. One is the interface velocity experiment of PBX-9501. Another is the plate push experiment of PBX-9502. Both of the examples include the shock initiation process of condensed explosive.

Findings

Numerical results show that the shock initiation process of condensed explosive can be well predicted by SPH method. The characteristics of detonation are captured in the simulation. The measured data in numerical examples are also in good agreement with the experimental data.

Research limitations/implications

Because of the research purpose is to study the ability of SPH for shock initiation simulation, only one-dimension numerical examples are discussed in the paper. Therefore, researchers are encouraged to extend and test the proposed method to two or three dimension shock initiation problems simulation.

Originality/value

This paper provides an alternative method for shock initiation simulation. The implemented method can overcome the weaknesses of traditional mesh based method in simulation of shock initiation problems.

Details

Engineering Computations, vol. 33 no. 2
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 4 January 2011

Yang Gang, Han Xu and Hu De'an

The purpose of this paper is to investigate the formation process of linear‐shaped charge jet using the smoothed particle hydrodynamics (SPH). Different material yield models are…

764

Abstract

Purpose

The purpose of this paper is to investigate the formation process of linear‐shaped charge jet using the smoothed particle hydrodynamics (SPH). Different material yield models are embed to test the performance of SPH method in the simulation of explosive driven metal liner. The effects of different ignition model to the formation of metal jet have also been studied.

Design/methodology/approach

The SPH method is used with the correction of artificial viscosity and penalty force to simulate the formation process of linear‐shaped charge jet, which includes the process of explosion and interaction between explosive gas and metal liner. The numerical results which got by SPH method are compared with these obtained by mesh‐based method. Different material yield models are implemented in the numerical examples to show the effect of material model to the formation process of metal jet. The single point and two point ignition models are used to study the effect of ignition models to the process of explosion and formation of metal jet.

Findings

Compared with the original mesh‐based method, the SPH method can simulate the physical process of linear‐shaped charge jet naturally, as well as the capturing of explosive wave propagation. The implementation of different material yields models to obtain the same formation tendency of metal jet, but some numerical difference exists. In two‐point ignition model the explosive pressure is superimposed at the location that two detonation waves intersect. Compared with two ignition models, the two point ignition model can form the metal jet faster and get the higher velocity metal jet.

Originality/value

There are a few references that address the application of SPH to simulate shaped charge explosion process. The feasibility of the SPH method to simulate the formation process of linear shaped charged jet is tested and verified in this paper. From the results which compared with mesh‐based method, it is shown that the SPH method has the advantage in tracking the large deformation of material and capturing the explosive wave propagation. The SPH method can be selected as a good alternative to traditional mesh‐based numerical methods in simulating similar explosively driven metal material problems which can be referenced from this paper.

Details

Engineering Computations, vol. 28 no. 1
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 27 May 2014

Hu De’an, Liu Chunhan, Xiao YiHua and Han Xu

The purpose of this paper is to confirm that the axisymmetric finite element and smoothed particle hydrodynamics (FE-SPH) adaptive coupling method is effective to solve explosion…

467

Abstract

Purpose

The purpose of this paper is to confirm that the axisymmetric finite element and smoothed particle hydrodynamics (FE-SPH) adaptive coupling method is effective to solve explosion problem in concrete based on the experiments.

Design/methodology/approach

Axisymmetric FE-SPH adaptive coupling method is first presented to simulate dynamic deformation process of concrete under internal blast loading. Using calculation codes of FE-SPH coupling method, numerical model of explosion is approximated initially by finite element method (FEM), and distorted finite elements are automatically converted into meshless particles to simulate damage, splash of concrete by SPH method, when equivalent plastic strain of elements reaches a specified value.

Findings

In this paper, damage process and pressure curve of concrete around explosive are analyzed and buried depth of explosive in concrete influence on damage effect under internal blast loading are obtained. Numerical analyses show that FE-SPH coupling method integrates high computational efficiency of FEM and advantages of SPH method, such as natural simulation to damage, splash and other characteristics of explosion in concrete.

Originality/value

This work shows that FE-SPH coupling method has good performance to solve the explosion problem.

Details

Engineering Computations, vol. 31 no. 4
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 3 April 2024

Shiang-Wuu Perng, Horng Wen Wu and De-An Huang

The purpose of this study is to advance turbulent thermal convection inside the constant heat-flux round tube inserted by multiple perforated twisted tapes.

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Abstract

Purpose

The purpose of this study is to advance turbulent thermal convection inside the constant heat-flux round tube inserted by multiple perforated twisted tapes.

Design/methodology/approach

The novel design of this study is accomplished by inserting several twisted tapes and drilling some circular perforations near the tape edge (C1, C3, C5: solid tapes; C2, C4, C6: perforated tapes). The turbulence flow appearances and thermal convective features are examined for various Reynolds numbers (8,000–14,000) using the renormalization group (RNG) κε turbulent model and Semi-Implicit Method for Pressure-Linked Equations (SIMPLE) algorithm.

Findings

The simulated outcomes reveal that inserting more perforated-twisted tapes into the heated round tube promotes turbulent thermal convection effectively. A swirling flow caused by the twisted tapes to produce the secondary flow jets between two reverse-spin tapes can combine with the main flow passing through the perforations at the outer edge to enhance the vortex flow. The primary factors are the quantity of twisted tapes and with/without perforations, as the perforation ratio remains at 2.5 in this numerical work. Weighing friction along the tube, C6 (four reverse-spin perforated-twisted tapes) brings the uppermost thermal-hydraulic performance of 1.23 under Re = 8,000.

Research limitations/implications

The constant thermo-hydraulic attributes of liquid water and the steady Newtonian fluid are research limitations for this simulated work.

Practical implications

The simulated outcomes will avail the inner-pipe design of a heat exchanger inserted by multiple perforated twisted tapes to enhance superior heat transfer.

Originality/value

These twisted tapes form tiny circular perforations along the tape edge to introduce the fluid flow through these bores and combine with the secondary flow induced between two reverse-spin tapes. This scheme enhances the swirling flow, turbulence intensity and fluid mixing to advance thermal convection since larger perforations cannot produce large jet velocity or the position of perforations is too far from the tape edge to generate a separated flow. Consequently, this work contributes a valuable cooling mechanism toward thermal engineering.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 5
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 8 May 2017

Rui Liu, Shan Liu, Yu-Rong Zeng and Lin Wang

The purpose of this paper is to investigate a new and practical decision support model of the coordinated replenishment and delivery (CRD) problem with multi-warehouse (M-CRD) to…

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Abstract

Purpose

The purpose of this paper is to investigate a new and practical decision support model of the coordinated replenishment and delivery (CRD) problem with multi-warehouse (M-CRD) to improve the performance of a supply chain. Two algorithms, tabu search-RAND (TS-RAND) and adaptive hybrid different evolution (AHDE) algorithm, are developed and compared as to the performance of each in solving the M-CRD problem.

Design/methodology/approach

The proposed M-CRD is more complex and practical than classical CRDs, which are non-deterministic polynomial-time hard problems. According to the structure of the M-CRD, a hybrid algorithm, TS-RAND, and AHDE are designed to solve the M-CRD.

Findings

Results of M-CRDs with different scales show that TS-RAND and AHDE are good candidates for handling small-scale M-CRD. TS-RAND can also find satisfactory solutions for large-scale M-CRDs. The total cost (TC) of M-CRD is apparently lower than that of a CRD with a single warehouse. Moreover, the TC is lower for the M-CRD with a larger number of optional warehouses.

Practical implications

The proposed M-CRD is helpful for managers to select the suitable warehouse and to decide the delivery scheduling with a coordinated replenishment policy under complex operations management situations. TS-RAND can be easily used by practitioners because of its robustness, easy implementation, and quick convergence.

Originality/value

Compared with the traditional CRDs with one warehouse, a better policy with lower TC can be obtained by the new M-CRD. Moreover, the proposed TS-RAND is a good candidate for solving the M-CRD.

Details

The International Journal of Logistics Management, vol. 28 no. 2
Type: Research Article
ISSN: 0957-4093

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Article
Publication date: 5 September 2018

Linhao Ouyang, Zijian Zhang, Xiaoling Huang and Shi Xie

The purpose of this study is to restore the spatial distribution of overseas remittance businesses in Shantou during the 1940s. It explores various socioeconomic factors that…

142

Abstract

Purpose

The purpose of this study is to restore the spatial distribution of overseas remittance businesses in Shantou during the 1940s. It explores various socioeconomic factors that influenced the concentration of local remittance business investment in real estate. By reconstructing the spatial distribution of remittance business activities in Shantou, this study hopes to lay a foundation for further analysis of the business strategies of Chaoshan merchants.

Design/methodology/approach

This research draws on information from the published Swatow Guide, archival sources and cadastral maps to identify the location of remittance enterprises and the native place and overseas networks of property owners.

Finding

This study reveals that the spatial distribution of the remittance enterprises was determined by the native place origins of local property owners, and that the inflow of overseas Chinese capital contributed to real estate development in Shantou.

Research limitations/implications

Despite the limited access to Chinese official archives, this paper manages to identify several building blocks and neighbors in Shantou for spatial analysis.

Practical implications

This study is the first attempt to use the geographical information system (GIS) method in Chinese urban history research and hopes to establish a larger historical database of Shantou as a sample for comparison.

Originality/value

This investigation advances the spatial study of urban history and overseas Chinese remittances in the maritime society of South China.

Details

Social Transformations in Chinese Societies, vol. 14 no. 2
Type: Research Article
ISSN: 1871-2673

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Article
Publication date: 3 July 2017

Arman Shojaei, Mirco Zaccariotto and Ugo Galvanetto

The paper aims to use a switching technique which allows to couple a nonlocal bond-based Peridynamic approach to the Meshless Local Exponential Basis Functions (MLEBF) method…

656

Abstract

Purpose

The paper aims to use a switching technique which allows to couple a nonlocal bond-based Peridynamic approach to the Meshless Local Exponential Basis Functions (MLEBF) method, based on classical continuum mechanics, to solve planar problems.

Design/methodology/approach

The coupling has been achieved in a completely meshless scheme. The domain is divided in three zones: one in which only Peridynamics is applied, one in which only the meshless method is applied and a transition zone where a gradual transition between the two approaches takes place.

Findings

The new coupling technique generates overall grids that are not affected by ghost forces. Moreover, the use of the meshless approach can be limited to a narrow boundary region of the domain, and in this way, it can be used to remove the “surface effect” from the Peridynamic solution applied to all internal points.

Originality/value

The current study paves the road for future studies on dynamic and static crack propagation problems.

Details

Engineering Computations, vol. 34 no. 5
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 1 March 1994

Virginia Ortiz‐Repiso and Yolanda Ríos

Library automation in Spain has undergone considerable growth during the 1990s, with the university library sector in particular making efforts to keep up with automation trends…

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Abstract

Library automation in Spain has undergone considerable growth during the 1990s, with the university library sector in particular making efforts to keep up with automation trends. Due to the installation of automated management systems in nearly all universities, the creation of university library networks, and the growing accessibility of automated bibliographic information as well as online information such as CDROM, it can be said that university library automation (as opposed to other library sectors) is becoming well established and is developing in a standardised fashion. It is clear that this standardisation aids interlibrary communication, although there is a considerable amount of ground still to be covered. The exchange of bibliographical information required by the Spanish Library System Law (Reglamento del Sistema Español de Bibliotecas) falls well short of what is really needed. The business of cataloguing and classifying library stock continues to take up a lot of time. If shared cataloguing existed, this time could and should be spent on improving user services. The National Library is still not the figurehead of the Spanish system. In conclusion, there is still an appreciable lack of organisation and, on many occasions, projects are started without the necessary planning.

Details

Online and CD-Rom Review, vol. 18 no. 3
Type: Research Article
ISSN: 1353-2642

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Article
Publication date: 26 April 2022

Nicola Bilstein, Peeter W.J. Verlegh, Jan Klostermann and Ezgi Akpinar

Consumers play a central role in the creation of transformative value, enhancing the well-being of people and the planet. With this article, the authors synthesize service and…

702

Abstract

Purpose

Consumers play a central role in the creation of transformative value, enhancing the well-being of people and the planet. With this article, the authors synthesize service and communication scholars' views to conceptually discuss opportunities and challenges on how to involve consumers in the ideation, creation and dissemination of transformative value. In doing so, the authors identify avenues for future research.

Design/methodology/approach

This research relies on a review of service and communication literature, connecting their insights to real world examples.

Findings

Consumers are involved in the ideation, creation and dissemination of transformative value by engaging in customer innovation, customer participation and customer dissemination behaviors. In relation to these types of customer involvement, four overarching research themes emerge in the context of transformative services: (1) the voice of the non-customer, (2) protecting vulnerable customers, (3) consumer literacy and (4) WOM as a double-edged sword.

Originality/value

This research contributes to transformative service research by assessing the opportunities and challenges related to customers' involvement in the ideation, creation and dissemination of transformative value. Additionally, it identifies avenues for the future at the intersection of communication and service research.

Details

Journal of Service Management, vol. 33 no. 4/5
Type: Research Article
ISSN: 1757-5818

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Article
Publication date: 13 August 2024

Ricardo Pereira, Ingrid Weingärtner Reis, Vânia Ulbricht and Neri dos Santos

The purpose of this study is to analyze the relationship between academic writing and generative artificial intelligence (AI).

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Abstract

Purpose

The purpose of this study is to analyze the relationship between academic writing and generative artificial intelligence (AI).

Design/methodology/approach

This paper is characterized as exploratory and descriptive, with a qualitative approach. Two approaches were used: the first, a narrative review of the literature with a systematic search from which a data collection stage was carried out using asynchronous interviews by means of an online questionnaire.

Findings

The results indicate that generative AI should be seen as a complementary tool for creative and critical academic writing. The data collected also highlighted issues related to academic dishonesty and the new type of plagiarism – plagiarism made possible by technologies – as well as issues of authorship and legitimacy of work carried out with AI and the loss of reflective and critical thinking and creativity.

Research limitations/implications

The considerable increase in resources using AI in all dimensions of human life.

Practical implications

The impact that the use of generative AIs can have on the creation of knowledge and the dissemination of scientific research.

Social implications

The impact that the use of generative AIs can have on the creation of knowledge and on the dissemination of scientific research.

Originality/value

The need for academia to anticipate the use of AI in academic writing and to incorporate its benefits into this process, especially considering researchers in training.

Objetivo

El objetivo de este artículo es analizar la relación entre la escritura académica y la inteligencia artificial generativa.

Proyecto/metodología/enfoque

Este artículo se caracteriza por ser exploratorio y descriptivo, con un enfoque cualitativo. Se utilizaron dos enfoques: el primero, una revisión narrativa de la literatura con una búsqueda sistemática, a partir de la cual se llevó a cabo una etapa de recogida de datos mediante entrevistas asincrónicas a través de un cuestionario online.

Resultados

Los resultados indican que la IA generativa debe considerarse una herramienta complementaria para la escritura académica creativa y crítica. Los datos recogidos también pusieron de manifiesto cuestiones relacionadas con la deshonestidad académica y el nuevo tipo de plagio, el plagio posibilitado por las tecnologías, así como cuestiones de autoría y legitimidad del trabajo realizado con Inteligencia Artificial, la pérdida de pensamiento reflexivo y crítico y la creatividad.

Originalidade

La necesidad de que el mundo académico se anticipe al uso de la IA en la escritura académica e incorpore sus ventajas a este proceso, considerando principalmente a los investigadores en formación.

Limitaciones/implicaciones de la investigación

El considerable aumento de los recursos que utilizan la IA en todas las dimensiones de la vida humana.

Implicaciones prácticas

El impacto que puede tener el uso de las IA generativas en la creación de conocimiento y la difusión de la investigación científica.

Implicaciones sociales

El impacto que puede tener el uso de las IA generativas en la creación de conocimiento y la difusión de la investigación científica.

Objetivo

O objetivo deste artigo é analisar a relação entre a redação acadêmica e a inteligência artificial generativa.

Projeto/metodologia/abordagem

Este artigo é caracterizado como exploratório e descritivo, com uma abordagem qualitativa. Foram usadas duas abordagens: a primeira, uma revisão narrativa da literatura com uma busca sistemática, a partir da qual foi realizada uma etapa de coleta de dados usando entrevistas assíncronas por meio de um questionário on-line.

Resultados

Os resultados indicam que a IA generativa deve ser vista como uma ferramenta complementar para a redação acadêmica criativa e crítica. Os dados coletados também destacaram questões relacionadas à desonestidade acadêmica e ao novo tipo de plágio - o plágio possibilitado pelas tecnologias, bem como questões de autoria e legitimidade do trabalho realizado com a Inteligência Artificial, a perda do pensamento reflexivo e crítico e da criatividade.

Originalidade

A necessidade de a academia antecipar o uso da IA na redação acadêmica e incorporar seus benefícios nesse processo, considerando principalmente pesquisadores em formação.

Limitações/implicações da pesquisa

O aumento considerável de recursos usando IA em todas as dimensões da vida humana.

Implicações práticas

O impacto que o uso de IAs generativas pode ter sobre a criação de conhecimento e a disseminação de pesquisas científicas.

Implicações sociais

O impacto que o uso de IAs geradoras pode ter na criação de conhecimento e na disseminação de pesquisas científicas.

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