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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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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

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

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) κ−ε turbulent model and Semi-Implicit Method for Pressure-Linked Equations (SIMPLE) algorithm.

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.

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

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

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.

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.

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.

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.

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.

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.

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.

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.

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.

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

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.

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

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.

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.

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.

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

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.

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.

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

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.

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.

Les mutations importantes observées depuis une quinzaine d'années dans tous les domaines de la vie se reflètent dans le tourisme, ses services et ses produits. De nouvelles formes de vacances, de voyages et de loisirs émergent et prennent le pas sur les types les plus classiques. Face à cette montée de nouvelles conceptions, dont le tourisme alternatif est devenu le symbole le plus évident, se font entendre ceux qui estiment qu'il ne faut plus considérer le patrimoine de manière élitiste, qu'il existe de nouvelles formes de patrimoine à protéger, mettre en valeur et montrer aux touristes et aux populations.