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Motivated by the acoustics of motor vehicles, a coupled fluid–solid system is considered. The air pressure is modeled by the Helmholtz equation, and the structure displacement is described by elastodynamic equations. The acoustic–structure interaction is modeled by coupling conditions on the common interface. First, the existence and uniqueness of solutions are investigated, and then, after recalling fundamental notions of shape optimization, the tensor form of the distributed shape derivative is obtained for the coupled problem. It is then applied to the minimization of the sound pressure by variation of the structure shape through the positioning of beads.

The existence and uniqueness of solutions up to eigenfrequencies are shown by the Fredholm–Riesz–Schauder theory using a novel decomposition into an isomorphism and a compact operator. For the design optimization, the distributed shape derivative is obtained using the averaged adjoint method. It is then used in a closed 3D optimization process of the position of a bead for noise reduction. In this process, the C++ library concepts are used to solve the differential equations on hexahedral meshes with the finite element method of higher order.

The existence and uniqueness of solutions have been shown for the case without absorption, where the given proof allows for extension to the case with absorption in the domain or via boundary conditions. The theoretical results show that the averaged adjoint can be applied to compute distributed shape derivatives in the context of acoustic–structure interaction. The numerical results show that the distributed shape derivative can be used to reduce the sound pressure at a chosen frequency via rigid motions of a nonsmooth shape.

The proof of shape differentiability and the calculation of the distributed shape derivative in tensor form allows to consider nonsmooth shapes for the optimization, which is particularly relevant for the optimal placement of beads or stampings in a structural-acoustic system.

The purpose of this paper is to reduce the number of join operations for retrieving Extensible Markup Language (XML) data from a relational database.

The paper proposes a new approach to eliminate the join operations for parent‐child traversing and/or sibling searching such that the performance of query processing could be improved. The rationale behind the design of the proposed approach is to distribute the structural information into relational databases.

The paper finds that the number of join operations which are needed for processing parent‐child traversal and sibling search can be bounded under the proposed approach. It also verifies the capability of the proposed approach by a series of experiments based on the XMark benchmark, for which it has encouraging results.

Compared with previous approaches based on the structure encoding method, the proposed approach needs more space to store additional immediate predecessor's IDs. However, the approach has similar performance to others and it is much easier to implement.

The experimental results show that the performance of the proposed approach is less than 3 per cent of the well‐known MonetDB approach for processing benchmark queries. Moreover, its bulkloading time is much less than that for the MonetDB. There is no doubt that the approach is efficient for accessing XML data with acceptable overheads.

This paper contributes to the implementations of XML database systems.

To provide a more requirements‐driven workload model for eXtensible Markup Language (XML) benchmark over the electronic data exchange and management in collaborative commerce.

A three‐component workload requirements model is formulated. They are the XML object model, the XML query operation model, and the control model. The object model extended from W3C data model gives a set of more generic data and document model. The query model enhanced from current and common benchmarks gives a more generalized set of standard and open queries against XML data and documents. The control model compiled from TPC and industry standards gives a set of more systematic experimental variables and performance metrics to set up and conduct an XML benchmark.

The long‐standing research issues of domain dependency and application irreproducibility of XML benchmarks are addressed, tackled and offered with a novel and computer‐aided alternative. Precision and cost‐effectiveness through a synthetic, standard, and scalable set of requirements‐driven workload model are presented.

XML constructs, constraints, and controls are investigated both in terms of data and documents. Workload formulation from the requirements analysis is explored. In‐depth schema, query, and control model to provide scalability and portability can be applied is developed.

Enterprise information integration over heterogeneous data sources has to be achieved through XML. Performance measurement and evaluation on XML is vital. With a more generic and generalized design, XML benchmark can become the key to the success of B2Bi interoperability and performance.

An origin of requirements‐driven benchmark modeling over collaborative commerce is presented. A novel extension on W3C XML model is created. A innovative enhancement from current XML benchmarks' query model is developed.

Nowadays there are a large number of XML documents on the web. This means that information retrieval techniques for searching XML documents are very important and necessary for internet users. Moreover, it is often said that users of search engines want to browse only relevant content in each document. Therefore, an effective XML element search aims to produce only the relevant elements or portions of an XML document. Based on the demand by users, the purpose of this paper is to propose and evaluate a method for obtaining more accurate search results in XML search.

The existing approaches generate a ranked list in descending order of each XML element's relevance to a search query; however, these approaches often extract irrelevant XML elements and overlook more relevant elements. To address these problems, the authors' approach extracts the relevant XML elements by considering the size of the elements and the relationships between the elements. Next, the authors score the XML elements to generate a refined ranked list. For scoring, the authors rank high the XML elements that are the most relevant to the user's information needs. In particular, each XML element is scored using the statistics of its descendant and ancestor XML elements.

The experimental evaluations show that the proposed method outperforms BM25E, a conventional approach, which neither reconstructs XML elements nor uses descendant and ancestor statistics. As a result, the authors found that the accuracy of an XML element search can be improved by reconstructing the XML elements and emphasizing the informative ones by applying the statistics of the descendant XML elements.

This work focused on the effectiveness of XML element search and the authors did not consider the search efficiency in this paper. One of the authors' next challenges is to reduce search time.

The paper proposes a method for improving the effectiveness of XML element search.

This paper aims to review the literature on the relationship between the implementation and performance of 4.0 industrial revolution (IR) technologies and explores the extent to which the effects of several internal and external contingency factors on these relationships have been considered by the existing empirical studies.

To achieve its purposes, this study follows a systematic review of the literature and explores the published empirical research on implementation and performance links of 4.0 IR technologies and the effects of contingency factors on these links in mainly three main databases.

The findings of this study reveal that in general several contingency factors tend to have significant effects on the implementation and performance links of 4.0 IR in several contexts. This study also shows that the effects of these contingencies the effects of contingency factors on the implementation and performance links of 4.0 IR technologies are receiving growing attention from researchers and have been studied in different approaches but the moderation approach was the highest.

The review of the literature conducted in this study refers to those studies published mostly by three main databases (i.e. Scopus, Web of Sciences, and Science Direct), and only those papers published in English, and thus does not contain publications out of these restrictions.

This is one of the early literature review studies to explore and discuss the current state of research on the effects of contingency factors on the relationships between the implementation and performance of 4.0 IR technologies in the contexts of logistics and supply chain management.

The rapid advancement of digital technologies has fundamentally changed the competitive dynamics of the logistics service industry and forced incumbent logistics service providers (LSPs) to digitalize. As many LSPs still struggle in advancing their digital transformation (DT), the purpose of this study is to discover barriers and identify organizational elements and associated leading practices for DT success at LSPs.

This study utilizes a two-stage approach. Stage 1 is devoted to a literature review. Stage 2, based on multiple case studies, analyzes information collected across nine international and global LSPs.

This research derives a practice-based definition of DT in the logistics service industry, and it has identified five barriers, eight success factors and associated leading practices for DT. The main obstacles LSPs struggle with, are the complexity of the logistics network and lack of resources, while the main success factor is a leader having and executing a DT vision, and creating a supportive organizational culture.

The results contribute to the emerging field of DT within the logistics and supply chain management literature and provide insights for practitioners regarding how to effectively implement it in a complex industry.

The authors analyze DT from the perspective of LSPs, traditionally not viewed as innovative companies. This study compares their DT with that of other companies.

Multichip module packaging enables a significant increase of interconnect densities and performance of electronic systems. Multichip module technology based on laminate materials (MCM‐L) is attractive due to low cost and use of the standard equipment used by PCB manufacturers. The most limiting factor for higher wiring densities in PCB technology is the mechanical drilling of plated‐through holes. Using 0.3 mm drill diameters, 0.5 mm land diameters are required, which limit the area for routing of tracks. Therefore, alternative dielectric materials, which can be structured photolithograpically, by plasma etching or laser drilling, are very attractive for MCM‐L technology. In this paper an epoxy resin layer, commercially available as a solder mask, is investigated as an interdielectric layer. Via hole drilling is investigated using an excimer laser. To show process feasibility, a two‐layer wiring system is fabricated using the excimer laser structured epoxy resin as an interdielectric layer on conventional epoxy board (FR‐4).

In recent years, sustainable supply chain practices (SSCPs), including corporate social responsibility (CSR), have been recognised as important means of developing firms’ sustainability performance (SP). However, empirical findings on the SSCP–SP interaction are inconsistent and even contradictory. This research presents a quantitative meta-analysis that aims to uncover SSCP–SP interactions based on the correlations found in previously published empirical studies.

Based on the main and moderating variables and selection criteria, 64 sample studies were selected after a systematic literature review and meta-analysis.

The findings confirm a positive correlation (0.438) between SSCP and SP. The results also reveal various critical moderators identified through meta-regression.

This study provides insights for operations managers and policymakers regarding the significance of control variables (e.g. ISO certification, type of economy, innovation approach, data collection method) on the relationship between SSCP and SP for business operations. This research uncovers the impacts of ISO regulations and proposed hypotheses through the lens of the natural resource-based view (NRBV) and institutional-based view (IBV).

This research is unique in that it provides a systematic view of the SSCP–SP interaction, validates the results through a theoretical lens (NRBV and IBV) and generalises the results by evaluating the moderation effects via checking prior literature.