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Fused deposit modeling (FDM) additive manufacturing technology is widely applied in recent years. However, there are many defects that may affect the surface quality, accuracy, or even cause the collapse of the parts. This paper presents a solution to the problem of detecting defects on the outer surface in the additive process of FDM.

A multi-view and all-round vision detection method is introduced where the detection field of view is changing with the vector of the outer surface during the printing process on the six degrees of freedom robot FDM printer.

After the image is preprocessed, this paper can identify the defects effectively according to its laminate structure, and introduces a mathematical matrix to represent the defects which will be classified into three typical types according to the geometry shape and area distribution.

This research only focuses on the feasibility of the defects detection method. To create the object of high quality, more research is needed to account for the process parameters which significantly cause the defects.

This work will help to detect the defects online, monitor the printing quality of the outer surface, reduce the waste of printed filaments, etc.

This study is among the first to present a multi-view and all-round vision detection method to detect defects on the outer surface in the additive process of FDM; proposes a means of identifying defects according to its laminate structure; and introduces a mathematical matrix to represent the defects which may be used in quality assessment.

The purpose of this paper is to examine the effects of perceived benefits, i.e. utilitarian value, hedonic value and social value, as well as perceived risk, on purchase intention in social commerce context.

To cast light on the factors motivating users’ intention to purchase in the context of social commerce, data of 277 users of social commerce in China were collected via an online survey.

Results show that satisfaction significantly and positively affects users’ purchase intention in social commerce context. In addition, utilitarian, hedonic and social values have significant and positive impacts on satisfaction and purchase intention; and utilitarian value is found to be the most salient factor influencing purchase intention, while hedonic value has the greatest effect on satisfaction. Moreover, perceived risk significantly and negatively affects satisfaction.

Extant research on social commerce has mainly focused on investigating how the general perceived value affects user behavior, but has less considered different dimensions of perceived value. Moreover, prior studies have explored the roles of utilitarian and hedonic values on user behavior; however, there is a lack of research on the effect of social value. The current study attempts to fill these research gaps.

The representation of Heterogeneous Object (HO) is divided into two categories: Data model (DM) and material evaluation paradigm (MEP). A hybrid methodology with geometry model and volumetric dataset to represent heterogeneous properties is proposed in this paper. Geometry model of an object can guarantee the accuracy of the final HO slices; and volumetric dataset lends the flexible manipulability and other advantages to HO representation. Two MEPs, namely distance field (DF) based and Fixed Reference Features & Active Grading Source(s) (FRF&AGS) are presented to facilitate the process of HO representation according to the designer)s input parameters. The DM can be modified interactively with users until the final satisfactory result is obtained. In this paper, a scheme of HO slicing is described. In this method, we utilize the slices contour of geometrical model as constraint to reconstruct the HO slices, which can theoretically achieve the same accuracy with the geometrical shape. Some examples of Heterogeneous object represented with our scheme are provided.

The purpose of this study is to explore the general and specific gratifications obtained from using microblog and WeChat.

To shed light on the difference of gratifications to use microblog and WeChat, 18 interviews with social media users in China were conducted.

Results reveal that three types of gratifications were obtained from using both microblog and WeChat: content gratification, social gratification and hedonic gratification. Also, the strength and components of each gratification for microblog and WeChat were different. Content gratification plays the most salient role in using microblog, while social gratification is the most important for WeChat usage. In addition, content gratification of microblog usage is related to information seeking and information sharing, while social gratification of WeChat usage is constituted by private social networking and convenient communication. Furthermore, content gratification of WeChat usage refers to high-quality information provided and information sharing, and entertainment and passing time develop hedonic gratification of microblog usage, while that of WeChat usage refers to entertainment.

Extant research has mainly focused on the gratifications of one social media and lacks studies comparing the motivations in using different social media. Also, only little research has identified the components of different gratifications and how they affect the adoption of different social media. The current study attempts to fill these research gaps.

The purpose of this paper is to present a novel method to design and fabricate aeroelastic wing models for wind tunnel tests based on stereolithography (SL). This method can ensure the structural similarity of both external and internal structures between models and prototypes.

An aluminum wing‐box was selected as the prototype, and its natural modes were studied by FEA and scaled down to obtain the desired dynamic behavior data. According to similarity laws, the structurally similar model was designed through a sequential design procedure of dimensional scaling, stiffness optimization and mass optimization. An SL model was then fabricated, and its actual natural modes was tested and compared with the desired data of the prototype.

The first two natural frequencies of the model presented strong correlation with the desired data of the prototype. Both the external and internal structures of the model matched the prototype closely. The SL‐based method can significantly reduce the total mass and simplify the locating operations of balance‐weights. The cost and time for the fabrication were reduced significantly.

Further investigation into the material properties of SL resins including stiffness and damping behaviors due to layered process is recommended toward higher prediction accuracy. Wind tunnel tests are needed to study the in situ performance and durability of SL models.

Although the paper takes a wing‐box as the study object, structurally similar SL models of entire wings can be obtained conveniently, benefiting from the low‐stiffness material properties of SL resins and the fabrication capacity to build complex structures of SL process. This paper enhances the versatility of using SL and other rapid prototyping processes to fabricate models to predict aeroelastic characteristics of aircraft.

Color is the dominant element of visual communication design. For cities, color is one of their characteristics. Improving the overall style of a city through the control and planning of architectural color has been a hot issue in urban control and planning in recent years. Considering color pollution in urban planning, we analyze the important role of color in visual communication design from the perspective of the visual communication concept of media art. The current situation of residential building colors in Shanghai City is investigated. We determine the residents’ preferences and requirements related to architectural exterior color on the basis of a data analysis of color and material selection, color matching, composition, and others. This study changes the traditional architectural color design concept that centers on individuals and lacks overall control. Specifically, we construct a set of multi-scale color controlling and planning systems at the macro-, meso-, and micro-scales. We also guide and control the urban architectural color such that it is in accordance with the systematic color planning strategy. This method enables the systematic and holistic external color planning of urban residential buildings.

The purpose of this paper is to use artificial intelligence to evaluate the risks of urban power network planning.

A fuzzy Bayesian least squares support vector machine (LS_SVM) model is established in this paper, which can learn the risk information of urban power network planning through artificial intelligence and acquire expert knowledge for its risk evaluation. With the advantage of possessing learning analog simulation precision and speed, the proposed model can be effectively applied in conducting a risk evaluation of an urban network planning system. First, fuzzy theory is applied to quantify qualitative risk factors of the planning to determine the fuzzy comprehensive evaluation value of the risk factors. Then, Bayesian evidence framework is utilized in LS_SVM model parameter optimization to automatically adjust the LS_SVM regularization parameters and nuclear parameters to obtain the best parameter values. Based on this, a risk comprehensive evaluation of urban network planning based on artificial intelligence is established.

The fuzzy Bayesian LS_SVM model established in this paper is an effective artificial intelligence method for risk comprehensive evaluation in urban network planning through empirical study.

The paper breaks new ground in using artificial intelligence to evaluate urban power network planning risks.

The evolution from emerging technologies to smart libraries is thoroughly analyzed thematically and bibliometrically in this research study, spanning 2013 through 2022. Finding and analyzing the significant changes, patterns and trends in the subject as they are represented in academic papers is the goal of this research.

Using bibliometric methodologies, this study gathered and examined a large corpus of research papers, conference papers and related material from several academic databases.

Starting with Artificial Intelligence (AI), the Internet of Things (IoT), Big Data (BD), Augmentation Reality/Virtual Reality and Blockchain Technology (BT), the study discusses the advent of new technologies and their effects on libraries. Using bibliometric analysis, this study looks at the evolution of publications over time, the geographic distribution of research and the most active institutions and writers in the area. A thematic analysis is also carried out to pinpoint the critical areas of study and trends in emerging technologies and smart libraries. Some emerging themes are information retrieval, personalized recommendations, intelligent data analytics, connected library spaces, real-time information access, augmented reality/virtual reality applications in libraries and strategies, digital literacy and inclusivity.

This study offers a thorough overview of the research environment by combining bibliometric and thematic analysis, illustrating the development of theories and concepts during the last ten years. The results of this study helps in understanding the trends and future research directions in emerging technologies and smart libraries. This study is an excellent source of information for academics, practitioners and policymakers involved in developing and applying cutting-edge technology in library environments.

This paper aims to draw upon motivated information processing theory to examine the sequential mediating roles of perspective taking and boundary spanning between transformational leadership and the creative performance of knowledge workers.

The study was carried out on a sample, including a dyad of 398 knowledge workers and their immediate supervisors in four research institutes in southwest China. The authors tested the theoretical model using structural equation modeling (SEM) and Mplus 7.0 software.

The results support the mediation model in which perspective taking was found to significantly and positively mediate the relationship between transformational leadership and boundary spanning. Boundary spanning was found to significantly and positively mediate the relationship between perspective taking and creative performance. Moreover, both perspective taking and boundary spanning were found to mediate the relationship between transformational leadership and creative performance.

The study findings imply that the transformational leadership behaviors of managers or supervisors nurture knowledge workers' perspective taking and their boundary spanning activities leading to creative performance.

The findings contribute new knowledge to the relationship between transformational leadership and creative performance by uncovering the causal chain of a cognitive mechanism (perspective taking) with a behavioral mechanism (boundary spanning).

The purpose of this paper is to solve the asynchrony problem between the logistics stream and the information stream in the complex product assembly executive process.

States of assembly and logistics are described by transitions, and implemented via logistics agents and assembly agents. Events in the assembly executive process are described by places, and mapped to radio frequency identification (RFID) tags' states. An agent‐based complex product assembly framework is proposed. Mobile agents are used to encapsulate task and data, and RFID tags' states are able to trigger dispatching of assembly agents and executing of assembly tasks. Assisted by mobile agents' retraction mechanism, on‐site data are carried back when assembly tasks are finished.

An assembly executive process Petri net and a mobile agent‐based complex product assembly framework are proposed.

Dynamic matching mechanism between assembly tasks and materials is achieved, and controlling and monitoring methods of complex product assembly executive process are enhanced.