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This study aims to first identify influencing factors of outsourcing decisions in construction projects systematically and further to unravel the interactions of these influencing factors from a holistic perspective.

This study concerns the design and analysis of two-stage studies, where, at the first stage, a systematic literature review and 48 semi-structured interviews with senior practitioners in construction firms were conducted to identify influencing factors in outsourcing decisions in construction projects. At the second stage, the decision-making and trial evaluation laboratory (DEMATEL) method was employed to explore the interactions between influencing factors and pathways of outsourcing decisions.

Three focuses for outsourcing decisions are outlined, revealing that outsourcing restrictions, strategic needs and cost objectives need to be considered in outsourcing decisions. In addition, the finding contributes to the integration of transaction costs perspective and capability perspective by unravelling the mechanism of how different factors work together.

This study outlines 18 influencing factors and three sequential focuses for outsourcing decision-making, providing a clearer understanding of each factor’s contribution for decision-makers.

Most of the existing studies stressed the net effect of individual outsourcing factors from a single logic and paid little attention to their complex causal relationship. This study develops a holistic perspective of the influencing factors of outsourcing in construction projects by contending the overall knowledge of outsourcing and analyzing the causal relationship between them.

This study provided a unique opportunity to analyze five generations of a small but continually evolving family-owned media organization with multiple media outlets operating across delivery platforms. The purpose of this paper is to identify variables that contributed to entrepreneurship and sustainability, holding the family business intact for more than 100 years.

This study used organizational ecology in a qualitative case study to interview entrepreneurs from three of five generations. Additionally, current employees, family and friends, along with letters, cards, published articles and financial data were included in the analysis. Entrepreneurial themes based on organizational ecology were identified including variation, selection, retention, as well as values, innovation, service and adaptability.

The company in this study began with the purchase of newspapers and start-up of a news service in 1904. By the third generation, entrepreneurial initiatives included additional newspapers, as well as a television start-up. In the fourth and fifth generations, the company evolved into what the family termed a “media development company” with a mix of revenue platforms including electronic newspapers, websites, radio stations, live events and syndicated programs.

Limitations included sample size and focus on the perspectives of family members. More research is needed to identify the struggles within the family media firm and the more troubling aspects of a family company as indicated in the literature and their possible downside to both employees and family members who work for the short term or long haul in smaller, family-owned companies.

Sustainability of family-owned media organizations occurred through a balance of entrepreneurial activities and family values. Revenue flows resulted from adapting business models from selling advertising in local newspapers to providing funding and other support to local businesses gaining footholds. Market innovation, risk and community-minded solutions resulted in survival through stages of variation, selection and retention.

For family media companies to thrive, entrepreneurship and adaptability are key. Significant contributions to theory from this study indicated organizational ecology is a useful tool in analyzing the evolution of a media company through stages of variation, selection and retention. After almost 80 years of operation in the retention stage, the company started over in the variation stage with new products including radio, internet, live events and community business ventures. Timely diversification was key as media and community landscapes changed.

Unique findings indicated sustainability came through a family-oriented approach to business that carried on throughout generations: a long-term view with a commitment to family values, the promotion of entrepreneurial opportunities for family and non-family members and an external focus as media development companies on the success of local businesses and communities in which they operated.

This article aims to provide a brief overview of the field now known as “evolutionary developmental robotics (evo-devo-robo)”, which is based on the concept and principles of evolutionary and development principles such as evolutionary developmental psychology, evolutionary developmental biology (evo-devo) and evolutionary cognitive neuroscience.

Evo-devo-robo is a new field bringing together developmental robotics and evolutionary robotics to form a new research area. Basic concepts and the origins of the field are described, and then some basic principles of evo-devo-robo that have been developed so far are discussed.

Finally, some misunderstand concepts and the most promising future research developments in this area are discussed.

Basic concepts and the origins of the field are described, and then some basic principles of evo-devo-robo that have been developed so far are discussed. Finally, some misunderstood concepts and the most promising future research developments in this area are discussed.

Intelligent prediction of node localization in wireless sensor networks (WSNs) is a major concern for researchers. The huge amount of data generated by modern sensor array systems required computationally efficient calibration techniques. This paper aims to improve localization accuracy by identifying obstacles in the optimization process and network scenarios.

The proposed method is used to incorporate distance estimation between nodes and packet transmission hop counts. This estimation is used in the proposed support vector machine (SVM) to find the network path using a time difference of arrival (TDoA)-based SVM. However, if the data set is noisy, SVM is prone to poor optimization, which leads to overlapping of target classes and the pathways through TDoA. The enhanced gray wolf optimization (EGWO) technique is introduced to eliminate overlapping target classes in the SVM.

The performance and efficacy of the model using existing TDoA methodologies are analyzed. The simulation results show that the proposed TDoA-EGWO achieves a higher rate of detection efficiency of 98% and control overhead of 97.8% and a better packet delivery ratio than other traditional methods.

The proposed method is successful in detecting the unknown position of the sensor node with a detection rate greater than that of other methods.

The effective transfer of knowledge within an organization is critical for its sustainable competitive advantage. Based on the norm of reciprocity, it can be concluded that individuals’ primary motivation to transfer their treasured knowledge can be summarized as “trust,” that is, the individuals trust their selfless transfer behavior can be reciprocated by the recipients in the future.

In this study, a simulation model based on knowledge transfer behavior and reciprocal trust between individuals is built through agent-based modeling and simulation to investigate the factors that influence the efficiency of knowledge transfer within an organization.

Experiments are performed to test the impact of reciprocal trust and organizational structure on the efficiency of knowledge transfer.

The results indicate a significant role of key elements of reciprocal trust and organizational structure, which provides relevant practical guidance for both individuals and organization managers in the context of knowledge transfer.

As an advanced calculation methodology, reliability-based multidisciplinary design optimization (RBMDO) has been widely acknowledged for the design problems of modern complex engineering systems, not only because of the accurate evaluation of the impact of uncertain factors but also the relatively good balance between economy and safety of performance. However, with the increasing complexity of engineering technology, the proposed RBMDO method gradually cannot effectively solve the higher nonlinear coupled multidisciplinary uncertainty design optimization problems, which limits the engineering application of RBMDO. Many valuable works have been done in the RBMDO field in recent decades to tackle the above challenges. This study is to review these studies systematically, highlight the research opportunities and challenges, and attempt to guide future research efforts.

This study presents a comprehensive review of the RBMDO theory, mainly including the reliability analysis methods of different uncertainties and the decoupling strategies of RBMDO.

First, the multidisciplinary design optimization (MDO) preliminaries are given. The basic MDO concepts and the corresponding mathematical formulas are illustrated. Then, the procedures of three RBMDO methods with different reliability analysis strategies are introduced in detail. These RBMDO methods were proposed for the design optimization problems under different uncertainty types. Furtherly, an optimization problem for a certain operating condition of a turbine runner blade is introduced to illustrate the engineering application of the above method. Finally, three aspects of future challenges for RBMDO, namely, time-varying uncertainty analysis; high-precision surrogate models, and verification, validation and accreditation (VVA) for the model, are discussed followed by the conclusion.

The scope of this study is to introduce the RBMDO theory systematically. Three commonly used RBMDO-SORA methods are reviewed comprehensively, including the methods' general procedures and mathematical models.

The purpose of this paper is to propose and demonstrate a new additive manufacturing approach that breaks the layer-based point scanning limitations to increase fabrication speed, obtain better surface finish, achieve material flexibility and reduce equipment costs.

The freeform additive manufacturing approach conceptually views a 3D article as an assembly of freeform elements distributed spatially following a flexible 3D assembly structure, which conforms to the surface of the article and physically builds the article by sequentially forming the freeform elements by a vari-directional vari-dimensional capable material deposition mechanism. Vari-directional building along tangential directions of part surface gives surface smoothness. Vari-dimensional deposition maximizes material output to increase build rate wherever allowed and minimizes deposition sizes for resolution whenever needed.

Process steps based on geometric and data processing considerations were described. Dispensing and forming of basic vari-directional and vari-dimensional freeform elements and basic operations of joining them were developed using thermoplastics. Forming of 3D articles at build rates of 2-5 times the fused deposition modeling (FDM) rate was demonstrated and improvement over ten times was shown to be feasible. FDM compatible operations using 0.7 mm wire depositions from a variable exit-dispensing unit were demonstrated. Preliminary tests of a surface finishing process showed a result of 0.8-1.9 um Ra. Initial results of dispensing wax, tin alloy and steel were also shown.

This is the first time that both vari-directional and vari-dimensional material depositions are combined in a new freeform building method, which has potential impact on the FDM and other additive manufacturing methods.

Molecular dynamics is an emerging simulation technique in the field of machining in recent years. Many researchers have tried to simulate different processing methods of various materials with the theory of molecular dynamics (MD), and some preliminary conclusions have been obtained. However, the application of MD simulation is more limited compared with traditional finite element model (FEM) simulation technique due to the complex modeling approach and long computation time. Therefore, more studies on the MD simulations are required to provide a reliable theoretical basis for the nanoscale interpretation of grinding process. This study investigates the crystal structures, dislocations, force, temperature and subsurface damage (SSD) in the grinding of iron-nickel alloy using MD analysis.

In this study the simulation model is established on the basis of the workpiece and single cubic boron nitride (CBN) grit with embedded atom method and Morse potentials describing the forces and energies between different atoms. The effects of grinding parameters on the material microstructure are studied based on the simulation results.

When CBN grit goes through one of the grains, the arrangement of atoms within the grain will be disordered, but other grains will not be easily deformed due to the protection of the grain boundaries. Higher grinding speed and larger cutting depth can cause greater impact of grit on the atoms, and more body-centered cubic (BCC) structures will be destroyed. The dislocations will appear in grain boundaries due to the rearrangement of atoms in grinding. The increase of grinding speed results in the more transformation from BCC to amorphous structures.

This study is aimed to study the grinding of Fe-Ni alloy (maraging steel) with single grit through MD simulation method, and to reveal the microstructure evolution within the affected range of SSD layer in the workpiece. The simulation model of polycrystalline structure of Fe-Ni maraging steel and grinding process of single CBN grit is constructed based on the Voronoi algorithm. The atomic accumulation, transformation of crystal structures, evolution of dislocations as well as the generation of SSD are discussed according to the simulation results.

The purpose of this article is to understand the current research status and future development trends in the field of numerical simulation on rock mass grouting.

This article first searched the literature database (EI, Web of Science, CNKI, etc.) for keywords related to the numerical simulation of rock mass grouting to obtain the initial literature database. Then, from the initial database, several documents with strong relevance to the numerical simulation theme of rock mass grouting and high citation rate were selected; some documents from the references were selected as supplements, forming the sample database of this review study (a total of 90 articles). Finally, through sorting out the relationship among the literature, this literature review was carried out.

The numerical simulation of rock mass grouting is mainly based on the porous media model and the fractured media model. It has experienced the development process from Newtonian fluid to non-Newtonian fluid, from time-invariant viscosity to time-varying viscosity, and from generalized theoretical model to engineering application model. Based on this, this article summarizes four scientific problems that need to be solved in the future in this research field: the law of grout distribution at the cross fissures, the grout diffusion mechanism under multi-field coupling, more accurate grouting theoretical model and simulation technology with strong engineering applicability.

This research systematically analyzes the current research status and shortcomings of numerical simulation on rock mass grouting, summarizes four key issues in the future development of this research field and provides new ideas for the future research on numerical simulation on rock mass grouting.

This paper aims to investigate an efficient approach to model the electromagnetic behaviors and predict stray-field loss inside the magnetic steel plate under 3D harmonic magnetization conditions so as to effectively prevent the structural components from local overheating and insulation damage in electromagnetic devices.

An experimental setup is applied to measure all the magnetic properties of magnetic steel plate under harmonic excitations with different frequencies and phase angles. The measurement and numerical simulation are carried out based on the updated TEAM Problem 21 Model B+ (P210-B+), under the 3D harmonic magnetization conditions. An improved method to evaluate the stray-field loss is proposed, and harmonic flux distribution in the structural components is analyzed.

The influence of the harmonic order and phase angle on the stray-field loss in magnetic steel components are noteworthy. Based on the engineering-oriented benchmark models, the variations of stray-field losses and magnetic field distribution inside the magnetic components under harmonic magnetization conditions are presented and analyzed in detail.

The capacity of the multi-function harmonic source, used in this work, was not large enough, which limits the magnetization level. Up to now, further improvements to increase the harmonic source capacity and investigations of the electromagnetic behaviors of magnetic steel components under multi-harmonic and DC-AC hybrid excitations are in progress.

To accurately predict the stray-field loss in magnetic steel plate, the improved method based on the combination of magnetic measurement and numerical simulation is proposed. The effects of the frequency and phase angle on the stray-field loss are analyzed.